Hi
I had a look last night at making Quaternion a VALJO. I've done the following * changed the constructors to private and added equivalent of methods. * added a parse method * altered equals so that (like Complex) it uses Double.equals - gets round an edge case where Quaternions with the equivalence of -0 and 0 discovered while adding tests for hashCode * added a divide by scalar method * added a norm2 (square of norm) method * added some additional unit tests so it should now have 100% coverage I've raised a pull request, and I have also emailed an ICLA. I think two convenience divide methods performing qr^{-1} and r^{-1}q for q and r would be useful, but I couldn't think of nice names for them. Steve |
Hello.
On Thu, 29 Nov 2018 08:43:22 +0000, Steve Bosman wrote: > Hi > > I had a look last night at making Quaternion a VALJO. > > I've done the following > > * changed the constructors to private and added equivalent of > methods. > * added a parse method > * altered equals so that (like Complex) it uses Double.equals - gets > round > an edge case where Quaternions with the equivalence of -0 and 0 > discovered > while adding tests for hashCode > * added a divide by scalar method > * added a norm2 (square of norm) method > * added some additional unit tests so it should now have 100% > coverage Thanks! > > I've raised a pull request, I've commented it. > and I have also emailed an ICLA. Not received/acknowledged yet. [I guess that we have to wait before committing the contribution...] > I think two convenience divide methods performing qr^{-1} and r^{-1}q > for q > and r would be useful, but I couldn't think of nice names for them. What are the use-cases? Why aren't "multiply" and "inverse" enough? Regards, Gilles > > Steve --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
> > and I have also emailed an ICLA.
> Not received/acknowledged yet. I am now listed on the "Persons with signed CLAs but who are not (yet) committers." page. > > I think two convenience divide methods performing qr^{-1} and r^{-1}q > > for q > > and r would be useful, but I couldn't think of nice names for them. > What are the use-cases? > Why aren't "multiply" and "inverse" enough? I must admit I'm new to quaternions and stumbled into the project while trying to improve my understanding so I'm not going to claim great knowledge of how common these operations are. I was primarily thinking of Quaternion Interpolation - SLERP and SQUAD. It seems to me that you end up creating inverse instances and throwing them away a lot and I thought it would be good to reduce that overhead. Steve |
On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote:
>> > and I have also emailed an ICLA. > >> Not received/acknowledged yet. > > I am now listed on the "Persons with signed CLAs but who are not > (yet) > committers." page. Welcome! >> > I think two convenience divide methods performing qr^{-1} and >> r^{-1}q >> > for q >> > and r would be useful, but I couldn't think of nice names for >> them. > >> What are the use-cases? >> Why aren't "multiply" and "inverse" enough? > > I must admit I'm new to quaternions and stumbled into the project > while > trying to improve my understanding so I'm not going to claim great > knowledge of how common these operations are. I was primarily > thinking of > Quaternion Interpolation - SLERP and SQUAD. It seems to me that you > end up > creating inverse instances and throwing them away a lot and I thought > it > would be good to reduce that overhead. Surely, the class "Quaternion" is minimal but, before adding to the API, we be careful to have use-cases for low-level operations. Those mentioned above seems more high-level, tied to a specific domain (see also "Commons Geometry", another new component not yet released) but I may be wrong... Regards, Gilles > > Steve --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
Hi guys,
FYI, I've been working on a quaternion-related class named QuaternionRotation for commons-geometry (see link below). It includes slerp as well as several other geometry-oriented methods, such as conversion to/from axis-angle representations and creation from basis rotations. It's not quite ready for a merge yet since I still need to finish the Euler angle conversions. I did not use the Quaternion class from commons-numbers since I wanted to focus solely on using quaternions to represent 3D rotations. I felt like the commons-numbers class was too general for this. Regards, Matt https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> Apache Commons Geometry. Contribute to darkma773r/commons-geometry development by creating an account on GitHub. github.com ________________________________ From: Gilles <[hidden email]> Sent: Friday, November 30, 2018 9:37 AM To: [hidden email] Subject: Re: [numbers] Making Quaternion a VALJO On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >> > and I have also emailed an ICLA. > >> Not received/acknowledged yet. > > I am now listed on the "Persons with signed CLAs but who are not > (yet) > committers." page. Welcome! >> > I think two convenience divide methods performing qr^{-1} and >> r^{-1}q >> > for q >> > and r would be useful, but I couldn't think of nice names for >> them. > >> What are the use-cases? >> Why aren't "multiply" and "inverse" enough? > > I must admit I'm new to quaternions and stumbled into the project > while > trying to improve my understanding so I'm not going to claim great > knowledge of how common these operations are. I was primarily > thinking of > Quaternion Interpolation - SLERP and SQUAD. It seems to me that you > end up > creating inverse instances and throwing them away a lot and I thought > it > would be good to reduce that overhead. Surely, the class "Quaternion" is minimal but, before adding to the API, we be careful to have use-cases for low-level operations. Those mentioned above seems more high-level, tied to a specific domain (see also "Commons Geometry", another new component not yet released) but I may be wrong... Regards, Gilles > > Steve --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
Hello.
On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: > Hi guys, > > FYI, I've been working on a quaternion-related class named > QuaternionRotation for commons-geometry (see link below). It includes > slerp as well as several other geometry-oriented methods, such as > conversion to/from axis-angle representations and creation from basis > rotations. It's not quite ready for a merge yet since I still need to > finish the Euler angle conversions. > > I did not use the Quaternion class from commons-numbers since I > wanted to focus solely on using quaternions to represent 3D > rotations. > I felt like the commons-numbers class was too general for this. We need to explore further how to avoid duplication. Some questions: * Should "QuaternionRotation" inherit from "Quaternion"? * Should "Quaternion" be defined in [Geometry] (and removed from [Numbers])? * Are some utilities defined in "QuaternionRotation" general such that they could be part of the [Numbers] "Quaternion" API. An example might be the transformation between quaternion and matrix (represented as a double[3][3])? The second consideration could apply to any computation that does not require types defined in [Geometry]. For example, interpolation is a purely quaternion-internal operation. It looks to me that it should be possible to come up with a design that defines "rotation" in [Geometry] which uses a "quaternion" defined in [Numbers]. Otherwise, one would wonder why "Complex" is also not in [Geometry] (for 2D rotations). Best regards, Gilles > > Regards, > Matt > > > > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > > [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> > > > darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> > Apache Commons Geometry. Contribute to darkma773r/commons-geometry > development by creating an account on GitHub. > github.com > > > > > ________________________________ > From: Gilles <[hidden email]> > Sent: Friday, November 30, 2018 9:37 AM > To: [hidden email] > Subject: Re: [numbers] Making Quaternion a VALJO > > On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>> > and I have also emailed an ICLA. >> >>> Not received/acknowledged yet. >> >> I am now listed on the "Persons with signed CLAs but who are not >> (yet) >> committers." page. > > Welcome! > >>> > I think two convenience divide methods performing qr^{-1} and >>> r^{-1}q >>> > for q >>> > and r would be useful, but I couldn't think of nice names for >>> them. >> >>> What are the use-cases? >>> Why aren't "multiply" and "inverse" enough? >> >> I must admit I'm new to quaternions and stumbled into the project >> while >> trying to improve my understanding so I'm not going to claim great >> knowledge of how common these operations are. I was primarily >> thinking of >> Quaternion Interpolation - SLERP and SQUAD. It seems to me that you >> end up >> creating inverse instances and throwing them away a lot and I >> thought >> it >> would be good to reduce that overhead. > > Surely, the class "Quaternion" is minimal but, before adding to > the API, we be careful to have use-cases for low-level operations. > Those mentioned above seems more high-level, tied to a specific > domain (see also "Commons Geometry", another new component not yet > released) but I may be wrong... > > Regards, > Gilles > >> >> Steve > --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote:
> Hello. > > On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >> Hi guys, >> >> FYI, I've been working on a quaternion-related class named >> QuaternionRotation for commons-geometry (see link below). It >> includes >> slerp as well as several other geometry-oriented methods, such as >> conversion to/from axis-angle representations and creation from >> basis >> rotations. It's not quite ready for a merge yet since I still need >> to >> finish the Euler angle conversions. >> >> I did not use the Quaternion class from commons-numbers since I >> wanted to focus solely on using quaternions to represent 3D >> rotations. >> I felt like the commons-numbers class was too general for this. > > We need to explore further how to avoid duplication. > > Some questions: > * Should "QuaternionRotation" inherit from "Quaternion"? > * Should "Quaternion" be defined in [Geometry] (and removed from > [Numbers])? > * Are some utilities defined in "QuaternionRotation" general > such that they could be part of the [Numbers] "Quaternion" API. > An example might be the transformation between quaternion and > matrix (represented as a double[3][3])? > > The second consideration could apply to any computation that does > not require types defined in [Geometry]. For example, interpolation > is a purely quaternion-internal operation. s/second/third/ > > It looks to me that it should be possible to come up with a design > that defines "rotation" in [Geometry] which uses a "quaternion" > defined in [Numbers]. > Otherwise, one would wonder why "Complex" is also not in [Geometry] > (for 2D rotations). > > Best regards, > Gilles > >> >> Regards, >> Matt >> >> >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >> >> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >> >> >> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >> Apache Commons Geometry. Contribute to darkma773r/commons-geometry >> development by creating an account on GitHub. >> github.com >> >> >> >> >> ________________________________ >> From: Gilles <[hidden email]> >> Sent: Friday, November 30, 2018 9:37 AM >> To: [hidden email] >> Subject: Re: [numbers] Making Quaternion a VALJO >> >> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>> > and I have also emailed an ICLA. >>> >>>> Not received/acknowledged yet. >>> >>> I am now listed on the "Persons with signed CLAs but who are not >>> (yet) >>> committers." page. >> >> Welcome! >> >>>> > I think two convenience divide methods performing qr^{-1} and >>>> r^{-1}q >>>> > for q >>>> > and r would be useful, but I couldn't think of nice names for >>>> them. >>> >>>> What are the use-cases? >>>> Why aren't "multiply" and "inverse" enough? >>> >>> I must admit I'm new to quaternions and stumbled into the project >>> while >>> trying to improve my understanding so I'm not going to claim great >>> knowledge of how common these operations are. I was primarily >>> thinking of >>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that you >>> end up >>> creating inverse instances and throwing them away a lot and I >>> thought >>> it >>> would be good to reduce that overhead. >> >> Surely, the class "Quaternion" is minimal but, before adding to >> the API, we be careful to have use-cases for low-level operations. >> Those mentioned above seems more high-level, tied to a specific >> domain (see also "Commons Geometry", another new component not yet >> released) but I may be wrong... >> >> Regards, >> Gilles >> >>> >>> Steve >> > --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
Unless anyone objects, I'm going to continue with what I'm working on with QuaternionRotation and create a merge request. That way, we'll at least have a reference implementation and baseline functionality for commons-geometry that we can modify later based on what's decided here.
-Matt ________________________________ From: Gilles <[hidden email]> Sent: Saturday, December 1, 2018 9:40 PM To: [hidden email] Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: Making Quaternion a VALJO) On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: > Hello. > > On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >> Hi guys, >> >> FYI, I've been working on a quaternion-related class named >> QuaternionRotation for commons-geometry (see link below). It >> includes >> slerp as well as several other geometry-oriented methods, such as >> conversion to/from axis-angle representations and creation from >> basis >> rotations. It's not quite ready for a merge yet since I still need >> to >> finish the Euler angle conversions. >> >> I did not use the Quaternion class from commons-numbers since I >> wanted to focus solely on using quaternions to represent 3D >> rotations. >> I felt like the commons-numbers class was too general for this. > > We need to explore further how to avoid duplication. > > Some questions: > * Should "QuaternionRotation" inherit from "Quaternion"? > * Should "Quaternion" be defined in [Geometry] (and removed from > [Numbers])? > * Are some utilities defined in "QuaternionRotation" general > such that they could be part of the [Numbers] "Quaternion" API. > An example might be the transformation between quaternion and > matrix (represented as a double[3][3])? > > The second consideration could apply to any computation that does > not require types defined in [Geometry]. For example, interpolation > is a purely quaternion-internal operation. s/second/third/ > > It looks to me that it should be possible to come up with a design > that defines "rotation" in [Geometry] which uses a "quaternion" > defined in [Numbers]. > Otherwise, one would wonder why "Complex" is also not in [Geometry] > (for 2D rotations). > > Best regards, > Gilles > >> >> Regards, >> Matt >> >> >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >> >> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >> >> >> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >> Apache Commons Geometry. Contribute to darkma773r/commons-geometry >> development by creating an account on GitHub. >> github.com >> >> >> >> >> ________________________________ >> From: Gilles <[hidden email]> >> Sent: Friday, November 30, 2018 9:37 AM >> To: [hidden email] >> Subject: Re: [numbers] Making Quaternion a VALJO >> >> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>> > and I have also emailed an ICLA. >>> >>>> Not received/acknowledged yet. >>> >>> I am now listed on the "Persons with signed CLAs but who are not >>> (yet) >>> committers." page. >> >> Welcome! >> >>>> > I think two convenience divide methods performing qr^{-1} and >>>> r^{-1}q >>>> > for q >>>> > and r would be useful, but I couldn't think of nice names for >>>> them. >>> >>>> What are the use-cases? >>>> Why aren't "multiply" and "inverse" enough? >>> >>> I must admit I'm new to quaternions and stumbled into the project >>> while >>> trying to improve my understanding so I'm not going to claim great >>> knowledge of how common these operations are. I was primarily >>> thinking of >>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that you >>> end up >>> creating inverse instances and throwing them away a lot and I >>> thought >>> it >>> would be good to reduce that overhead. >> >> Surely, the class "Quaternion" is minimal but, before adding to >> the API, we be careful to have use-cases for low-level operations. >> Those mentioned above seems more high-level, tied to a specific >> domain (see also "Commons Geometry", another new component not yet >> released) but I may be wrong... >> >> Regards, >> Gilles >> >>> >>> Steve >> > --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote:
> Unless anyone objects, I'm going to continue with what I'm working on I certainly don't object on your working to improve the geometry code, but wherever that work overlaps with code being worked on elsewhere (in this case, the "Quaternion" class), then we'd rather have a discussion happening here first. > with QuaternionRotation and create a merge request. That way, we'll > at > least have a reference implementation and baseline functionality for > commons-geometry that we can modify later based on what's decided > here. My questions below are a start; I'm waiting for answers. Code duplication is bad (TM). Regards, Gilles > > -Matt > ________________________________ > From: Gilles <[hidden email]> > Sent: Saturday, December 1, 2018 9:40 PM > To: [hidden email] > Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: > Making Quaternion a VALJO) > > On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: >> Hello. >> >> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >>> Hi guys, >>> >>> FYI, I've been working on a quaternion-related class named >>> QuaternionRotation for commons-geometry (see link below). It >>> includes >>> slerp as well as several other geometry-oriented methods, such as >>> conversion to/from axis-angle representations and creation from >>> basis >>> rotations. It's not quite ready for a merge yet since I still need >>> to >>> finish the Euler angle conversions. >>> >>> I did not use the Quaternion class from commons-numbers since I >>> wanted to focus solely on using quaternions to represent 3D >>> rotations. >>> I felt like the commons-numbers class was too general for this. >> >> We need to explore further how to avoid duplication. >> >> Some questions: >> * Should "QuaternionRotation" inherit from "Quaternion"? >> * Should "Quaternion" be defined in [Geometry] (and removed from >> [Numbers])? >> * Are some utilities defined in "QuaternionRotation" general >> such that they could be part of the [Numbers] "Quaternion" API. >> An example might be the transformation between quaternion and >> matrix (represented as a double[3][3])? >> >> The second consideration could apply to any computation that does >> not require types defined in [Geometry]. For example, interpolation >> is a purely quaternion-internal operation. > > s/second/third/ > >> >> It looks to me that it should be possible to come up with a design >> that defines "rotation" in [Geometry] which uses a "quaternion" >> defined in [Numbers]. >> Otherwise, one would wonder why "Complex" is also not in [Geometry] >> (for 2D rotations). >> >> Best regards, >> Gilles >> >>> >>> Regards, >>> Matt >>> >>> >>> >>> >>> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>> >>> >>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>> >>> >>> >>> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>> Apache Commons Geometry. Contribute to darkma773r/commons-geometry >>> development by creating an account on GitHub. >>> github.com >>> >>> >>> >>> >>> ________________________________ >>> From: Gilles <[hidden email]> >>> Sent: Friday, November 30, 2018 9:37 AM >>> To: [hidden email] >>> Subject: Re: [numbers] Making Quaternion a VALJO >>> >>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>>> > and I have also emailed an ICLA. >>>> >>>>> Not received/acknowledged yet. >>>> >>>> I am now listed on the "Persons with signed CLAs but who are not >>>> (yet) >>>> committers." page. >>> >>> Welcome! >>> >>>>> > I think two convenience divide methods performing qr^{-1} and >>>>> r^{-1}q >>>>> > for q >>>>> > and r would be useful, but I couldn't think of nice names for >>>>> them. >>>> >>>>> What are the use-cases? >>>>> Why aren't "multiply" and "inverse" enough? >>>> >>>> I must admit I'm new to quaternions and stumbled into the project >>>> while >>>> trying to improve my understanding so I'm not going to claim great >>>> knowledge of how common these operations are. I was primarily >>>> thinking of >>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that >>>> you >>>> end up >>>> creating inverse instances and throwing them away a lot and I >>>> thought >>>> it >>>> would be good to reduce that overhead. >>> >>> Surely, the class "Quaternion" is minimal but, before adding to >>> the API, we be careful to have use-cases for low-level operations. >>> Those mentioned above seems more high-level, tied to a specific >>> domain (see also "Commons Geometry", another new component not yet >>> released) but I may be wrong... >>> >>> Regards, >>> Gilles >>> >>>> >>>> Steve >>> >> --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
I was just thinking from a practical standpoint. My current QuaternionRotation class is still in my working branch for GEOMETRY-14 and so isn't really accessible to anyone. If I can finish it up in its current state (hopefully very soon) and get it merged, then someone else will be able to work with it and blend the functionality with commons-numbers.
Here are some notes on your questions from before: * Should "QuaternionRotation" inherit from "Quaternion"? That would work conceptually. The quaternions in the QuaternionRotation class are standard quaternions that meet two other criteria: 1) they are unit length, and 2) their scalar component is greater than or equal to zero (in order to standardize the angles involved). The one sticking point here is that I'm not sure how this fits with the VALJO concept. If we can get this sorted, then this very well may be the best option. * Should "Quaternion" be defined in [Geometry] (and removed from [Numbers])? Perhaps. I've certainly only used them to represent 3D rotations. Are there any other use cases from commons-numbers? * Are some utilities defined in "QuaternionRotation" general such that they could be part of the [Numbers] "Quaternion" API. An example might be the transformation between quaternion and matrix (represented as a double[3][3])? The conversion to rotation matrix and slerp are the best candidates here. The other methods rely on core classes from commons-geometry, namely Vector3D. One more note: I decided to make a separate package for 3D rotations in my working branch for GEOMETRY-14, so QuaternionRotation is now at https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java. -Matt ________________________________ From: Gilles <[hidden email]> Sent: Sunday, December 2, 2018 3:57 PM To: [hidden email] Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: Making Quaternion a VALJO) On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: > Unless anyone objects, I'm going to continue with what I'm working on I certainly don't object on your working to improve the geometry code, but wherever that work overlaps with code being worked on elsewhere (in this case, the "Quaternion" class), then we'd rather have a discussion happening here first. > with QuaternionRotation and create a merge request. That way, we'll > at > least have a reference implementation and baseline functionality for > commons-geometry that we can modify later based on what's decided > here. My questions below are a start; I'm waiting for answers. Code duplication is bad (TM). Regards, Gilles > > -Matt > ________________________________ > From: Gilles <[hidden email]> > Sent: Saturday, December 1, 2018 9:40 PM > To: [hidden email] > Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: > Making Quaternion a VALJO) > > On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: >> Hello. >> >> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >>> Hi guys, >>> >>> FYI, I've been working on a quaternion-related class named >>> QuaternionRotation for commons-geometry (see link below). It >>> includes >>> slerp as well as several other geometry-oriented methods, such as >>> conversion to/from axis-angle representations and creation from >>> basis >>> rotations. It's not quite ready for a merge yet since I still need >>> to >>> finish the Euler angle conversions. >>> >>> I did not use the Quaternion class from commons-numbers since I >>> wanted to focus solely on using quaternions to represent 3D >>> rotations. >>> I felt like the commons-numbers class was too general for this. >> >> We need to explore further how to avoid duplication. >> >> Some questions: >> * Should "QuaternionRotation" inherit from "Quaternion"? >> * Should "Quaternion" be defined in [Geometry] (and removed from >> [Numbers])? >> * Are some utilities defined in "QuaternionRotation" general >> such that they could be part of the [Numbers] "Quaternion" API. >> An example might be the transformation between quaternion and >> matrix (represented as a double[3][3])? >> >> The second consideration could apply to any computation that does >> not require types defined in [Geometry]. For example, interpolation >> is a purely quaternion-internal operation. > > s/second/third/ > >> >> It looks to me that it should be possible to come up with a design >> that defines "rotation" in [Geometry] which uses a "quaternion" >> defined in [Numbers]. >> Otherwise, one would wonder why "Complex" is also not in [Geometry] >> (for 2D rotations). >> >> Best regards, >> Gilles >> >>> >>> Regards, >>> Matt >>> >>> >>> >>> >>> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>> >>> >>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>> >>> >>> >>> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>> Apache Commons Geometry. Contribute to darkma773r/commons-geometry >>> development by creating an account on GitHub. >>> github.com >>> >>> >>> >>> >>> ________________________________ >>> From: Gilles <[hidden email]> >>> Sent: Friday, November 30, 2018 9:37 AM >>> To: [hidden email] >>> Subject: Re: [numbers] Making Quaternion a VALJO >>> >>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>>> > and I have also emailed an ICLA. >>>> >>>>> Not received/acknowledged yet. >>>> >>>> I am now listed on the "Persons with signed CLAs but who are not >>>> (yet) >>>> committers." page. >>> >>> Welcome! >>> >>>>> > I think two convenience divide methods performing qr^{-1} and >>>>> r^{-1}q >>>>> > for q >>>>> > and r would be useful, but I couldn't think of nice names for >>>>> them. >>>> >>>>> What are the use-cases? >>>>> Why aren't "multiply" and "inverse" enough? >>>> >>>> I must admit I'm new to quaternions and stumbled into the project >>>> while >>>> trying to improve my understanding so I'm not going to claim great >>>> knowledge of how common these operations are. I was primarily >>>> thinking of >>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that >>>> you >>>> end up >>>> creating inverse instances and throwing them away a lot and I >>>> thought >>>> it >>>> would be good to reduce that overhead. >>> >>> Surely, the class "Quaternion" is minimal but, before adding to >>> the API, we be careful to have use-cases for low-level operations. >>> Those mentioned above seems more high-level, tied to a specific >>> domain (see also "Commons Geometry", another new component not yet >>> released) but I may be wrong... >>> >>> Regards, >>> Gilles >>> >>>> >>>> Steve >>> >> --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
Hi.
On Mon, 3 Dec 2018 03:56:02 +0000, Matt Juntunen wrote: > I was just thinking from a practical standpoint. My current > QuaternionRotation class is still in my working branch for > GEOMETRY-14 > and so isn't really accessible to anyone. If I can finish it up in > its > current state (hopefully very soon) and get it merged, then someone > else will be able to work with it and blend the functionality with > commons-numbers. Someone else? > > Here are some notes on your questions from before: > > * Should "QuaternionRotation" inherit from "Quaternion"? > > That would work conceptually. The quaternions in the > QuaternionRotation class are standard quaternions that meet two other > criteria: 1) they are unit length, and 2) their scalar component is > greater than or equal to zero (in order to standardize the angles > involved). It seems indeed the perfect case for inheritance. > The one sticking point here is that I'm not sure how this > fits with the VALJO concept. If we can get this sorted, then this > very > well may be the best option. What do you see as a potential issue? > > * Should "Quaternion" be defined in [Geometry] (and removed from > [Numbers])? > > Perhaps. I've certainly only used them to represent 3D rotations. Are > there any other use cases from commons-numbers? Not within [Numbers], but that's the point of those very low-level components/modules: they are common utilities used by higher-level components/libraries/applications. Given that "QuaternionRotation" is a special case of "Quaternion", it is logical to keep the latter at a lower-level, namely in [Numebers], and make [Geometry] depend on it. > > * Are some utilities defined in "QuaternionRotation" general > such that they could be part of the [Numbers] "Quaternion" API. > An example might be the transformation between quaternion and > matrix (represented as a double[3][3])? > > The conversion to rotation matrix and slerp are the best candidates > here. The other methods rely on core classes from commons-geometry, > namely Vector3D. Is "slerp" applicable to a general "Quaternion", or does it assume the additional requirements of "QuaternionRotation"? [Same question applies to all utilities in order to decide where to define them.] > > One more note: I decided to make a separate package for 3D rotations > in my working branch for GEOMETRY-14, so QuaternionRotation is now at > > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java. Could you please update it so that it inherits from "Quaternion"? Thanks, Gilles > > -Matt > ________________________________ > From: Gilles <[hidden email]> > Sent: Sunday, December 2, 2018 3:57 PM > To: [hidden email] > Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: > Making Quaternion a VALJO) > > On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: >> Unless anyone objects, I'm going to continue with what I'm working >> on > > I certainly don't object on your working to improve the geometry > code, but wherever that work overlaps with code being worked on > elsewhere (in this case, the "Quaternion" class), then we'd > rather have a discussion happening here first. > >> with QuaternionRotation and create a merge request. That way, we'll >> at >> least have a reference implementation and baseline functionality for >> commons-geometry that we can modify later based on what's decided >> here. > > My questions below are a start; I'm waiting for answers. > Code duplication is bad (TM). > > Regards, > Gilles > >> >> -Matt >> ________________________________ >> From: Gilles <[hidden email]> >> Sent: Saturday, December 1, 2018 9:40 PM >> To: [hidden email] >> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: >> Making Quaternion a VALJO) >> >> On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: >>> Hello. >>> >>> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >>>> Hi guys, >>>> >>>> FYI, I've been working on a quaternion-related class named >>>> QuaternionRotation for commons-geometry (see link below). It >>>> includes >>>> slerp as well as several other geometry-oriented methods, such as >>>> conversion to/from axis-angle representations and creation from >>>> basis >>>> rotations. It's not quite ready for a merge yet since I still need >>>> to >>>> finish the Euler angle conversions. >>>> >>>> I did not use the Quaternion class from commons-numbers since I >>>> wanted to focus solely on using quaternions to represent 3D >>>> rotations. >>>> I felt like the commons-numbers class was too general for this. >>> >>> We need to explore further how to avoid duplication. >>> >>> Some questions: >>> * Should "QuaternionRotation" inherit from "Quaternion"? >>> * Should "Quaternion" be defined in [Geometry] (and removed from >>> [Numbers])? >>> * Are some utilities defined in "QuaternionRotation" general >>> such that they could be part of the [Numbers] "Quaternion" API. >>> An example might be the transformation between quaternion and >>> matrix (represented as a double[3][3])? >>> >>> The second consideration could apply to any computation that does >>> not require types defined in [Geometry]. For example, >>> interpolation >>> is a purely quaternion-internal operation. >> >> s/second/third/ >> >>> >>> It looks to me that it should be possible to come up with a design >>> that defines "rotation" in [Geometry] which uses a "quaternion" >>> defined in [Numbers]. >>> Otherwise, one would wonder why "Complex" is also not in [Geometry] >>> (for 2D rotations). >>> >>> Best regards, >>> Gilles >>> >>>> >>>> Regards, >>>> Matt >>>> >>>> >>>> >>>> >>>> >>>> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>>> >>>> >>>> >>>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>>> >>>> >>>> >>>> >>>> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>>> Apache Commons Geometry. Contribute to darkma773r/commons-geometry >>>> development by creating an account on GitHub. >>>> github.com >>>> >>>> >>>> >>>> >>>> ________________________________ >>>> From: Gilles <[hidden email]> >>>> Sent: Friday, November 30, 2018 9:37 AM >>>> To: [hidden email] >>>> Subject: Re: [numbers] Making Quaternion a VALJO >>>> >>>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>>>> > and I have also emailed an ICLA. >>>>> >>>>>> Not received/acknowledged yet. >>>>> >>>>> I am now listed on the "Persons with signed CLAs but who are not >>>>> (yet) >>>>> committers." page. >>>> >>>> Welcome! >>>> >>>>>> > I think two convenience divide methods performing qr^{-1} and >>>>>> r^{-1}q >>>>>> > for q >>>>>> > and r would be useful, but I couldn't think of nice names for >>>>>> them. >>>>> >>>>>> What are the use-cases? >>>>>> Why aren't "multiply" and "inverse" enough? >>>>> >>>>> I must admit I'm new to quaternions and stumbled into the project >>>>> while >>>>> trying to improve my understanding so I'm not going to claim >>>>> great >>>>> knowledge of how common these operations are. I was primarily >>>>> thinking of >>>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that >>>>> you >>>>> end up >>>>> creating inverse instances and throwing them away a lot and I >>>>> thought >>>>> it >>>>> would be good to reduce that overhead. >>>> >>>> Surely, the class "Quaternion" is minimal but, before adding to >>>> the API, we be careful to have use-cases for low-level operations. >>>> Those mentioned above seems more high-level, tied to a specific >>>> domain (see also "Commons Geometry", another new component not yet >>>> released) but I may be wrong... >>>> >>>> Regards, >>>> Gilles >>>> >>>>> >>>>> Steve >>>> >>> --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
Hello.
After the discussion quote below, the conclusion was to go with inheritance: https://issues.apache.org/jira/browse/NUMBERS-80 However, it would make "Quaternion" fail the "ValJO" definition[1] that mandates that all constructors be private. Would a protected constructor really be an issue? [In the case of "Quaternion", the subclass constructor would only perform additional validation (cf. below for details).] Thanks, Gilles [1] https://blog.joda.org/2014/03/valjos-value-java-objects.html On Mon, 03 Dec 2018 10:31:42 +0100, Gilles wrote: > Hi. > > On Mon, 3 Dec 2018 03:56:02 +0000, Matt Juntunen wrote: >> I was just thinking from a practical standpoint. My current >> QuaternionRotation class is still in my working branch for >> GEOMETRY-14 >> and so isn't really accessible to anyone. If I can finish it up in >> its >> current state (hopefully very soon) and get it merged, then someone >> else will be able to work with it and blend the functionality with >> commons-numbers. > > Someone else? > >> >> Here are some notes on your questions from before: >> >> * Should "QuaternionRotation" inherit from "Quaternion"? >> >> That would work conceptually. The quaternions in the >> QuaternionRotation class are standard quaternions that meet two >> other >> criteria: 1) they are unit length, and 2) their scalar component is >> greater than or equal to zero (in order to standardize the angles >> involved). > > It seems indeed the perfect case for inheritance. > >> The one sticking point here is that I'm not sure how this >> fits with the VALJO concept. If we can get this sorted, then this >> very >> well may be the best option. > > What do you see as a potential issue? > >> >> * Should "Quaternion" be defined in [Geometry] (and removed from >> [Numbers])? >> >> Perhaps. I've certainly only used them to represent 3D rotations. >> Are >> there any other use cases from commons-numbers? > > Not within [Numbers], but that's the point of those very low-level > components/modules: they are common utilities used by higher-level > components/libraries/applications. > > Given that "QuaternionRotation" is a special case of "Quaternion", > it is logical to keep the latter at a lower-level, namely in > [Numebers], and make [Geometry] depend on it. > >> >> * Are some utilities defined in "QuaternionRotation" general >> such that they could be part of the [Numbers] "Quaternion" API. >> An example might be the transformation between quaternion and >> matrix (represented as a double[3][3])? >> >> The conversion to rotation matrix and slerp are the best candidates >> here. The other methods rely on core classes from commons-geometry, >> namely Vector3D. > > Is "slerp" applicable to a general "Quaternion", or does it assume > the additional requirements of "QuaternionRotation"? > [Same question applies to all utilities in order to decide where to > define them.] > >> >> One more note: I decided to make a separate package for 3D rotations >> in my working branch for GEOMETRY-14, so QuaternionRotation is now >> at >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java. > > Could you please update it so that it inherits from "Quaternion"? > > Thanks, > Gilles > >> >> -Matt >> ________________________________ >> From: Gilles <[hidden email]> >> Sent: Sunday, December 2, 2018 3:57 PM >> To: [hidden email] >> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: >> Making Quaternion a VALJO) >> >> On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: >>> Unless anyone objects, I'm going to continue with what I'm working >>> on >> >> I certainly don't object on your working to improve the geometry >> code, but wherever that work overlaps with code being worked on >> elsewhere (in this case, the "Quaternion" class), then we'd >> rather have a discussion happening here first. >> >>> with QuaternionRotation and create a merge request. That way, we'll >>> at >>> least have a reference implementation and baseline functionality >>> for >>> commons-geometry that we can modify later based on what's decided >>> here. >> >> My questions below are a start; I'm waiting for answers. >> Code duplication is bad (TM). >> >> Regards, >> Gilles >> >>> >>> -Matt >>> ________________________________ >>> From: Gilles <[hidden email]> >>> Sent: Saturday, December 1, 2018 9:40 PM >>> To: [hidden email] >>> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: >>> Making Quaternion a VALJO) >>> >>> On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: >>>> Hello. >>>> >>>> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >>>>> Hi guys, >>>>> >>>>> FYI, I've been working on a quaternion-related class named >>>>> QuaternionRotation for commons-geometry (see link below). It >>>>> includes >>>>> slerp as well as several other geometry-oriented methods, such as >>>>> conversion to/from axis-angle representations and creation from >>>>> basis >>>>> rotations. It's not quite ready for a merge yet since I still >>>>> need >>>>> to >>>>> finish the Euler angle conversions. >>>>> >>>>> I did not use the Quaternion class from commons-numbers since I >>>>> wanted to focus solely on using quaternions to represent 3D >>>>> rotations. >>>>> I felt like the commons-numbers class was too general for this. >>>> >>>> We need to explore further how to avoid duplication. >>>> >>>> Some questions: >>>> * Should "QuaternionRotation" inherit from "Quaternion"? >>>> * Should "Quaternion" be defined in [Geometry] (and removed from >>>> [Numbers])? >>>> * Are some utilities defined in "QuaternionRotation" general >>>> such that they could be part of the [Numbers] "Quaternion" API. >>>> An example might be the transformation between quaternion and >>>> matrix (represented as a double[3][3])? >>>> >>>> The second consideration could apply to any computation that does >>>> not require types defined in [Geometry]. For example, >>>> interpolation >>>> is a purely quaternion-internal operation. >>> >>> s/second/third/ >>> >>>> >>>> It looks to me that it should be possible to come up with a design >>>> that defines "rotation" in [Geometry] which uses a "quaternion" >>>> defined in [Numbers]. >>>> Otherwise, one would wonder why "Complex" is also not in >>>> [Geometry] >>>> (for 2D rotations). >>>> >>>> Best regards, >>>> Gilles >>>> >>>>> >>>>> Regards, >>>>> Matt >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>>>> >>>>> >>>>> >>>>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>>>> >>>>> >>>>> >>>>> >>>>> darkma773r/commons-geometry<https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java> >>>>> Apache Commons Geometry. Contribute to >>>>> darkma773r/commons-geometry >>>>> development by creating an account on GitHub. >>>>> github.com >>>>> >>>>> >>>>> >>>>> >>>>> ________________________________ >>>>> From: Gilles <[hidden email]> >>>>> Sent: Friday, November 30, 2018 9:37 AM >>>>> To: [hidden email] >>>>> Subject: Re: [numbers] Making Quaternion a VALJO >>>>> >>>>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>>>>> > and I have also emailed an ICLA. >>>>>> >>>>>>> Not received/acknowledged yet. >>>>>> >>>>>> I am now listed on the "Persons with signed CLAs but who are not >>>>>> (yet) >>>>>> committers." page. >>>>> >>>>> Welcome! >>>>> >>>>>>> > I think two convenience divide methods performing qr^{-1} and >>>>>>> r^{-1}q >>>>>>> > for q >>>>>>> > and r would be useful, but I couldn't think of nice names for >>>>>>> them. >>>>>> >>>>>>> What are the use-cases? >>>>>>> Why aren't "multiply" and "inverse" enough? >>>>>> >>>>>> I must admit I'm new to quaternions and stumbled into the >>>>>> project >>>>>> while >>>>>> trying to improve my understanding so I'm not going to claim >>>>>> great >>>>>> knowledge of how common these operations are. I was primarily >>>>>> thinking of >>>>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that >>>>>> you >>>>>> end up >>>>>> creating inverse instances and throwing them away a lot and I >>>>>> thought >>>>>> it >>>>>> would be good to reduce that overhead. >>>>> >>>>> Surely, the class "Quaternion" is minimal but, before adding to >>>>> the API, we be careful to have use-cases for low-level >>>>> operations. >>>>> Those mentioned above seems more high-level, tied to a specific >>>>> domain (see also "Commons Geometry", another new component not >>>>> yet >>>>> released) but I may be wrong... >>>>> >>>>> Regards, >>>>> Gilles >>>>> >>>>>> >>>>>> Steve >>>>> >>>> --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
I think this has already been worked out, but the main reason for no
inheritance is that is probably blocks future conversion to value types. Composition instead of inheritance is usually the right solution. Stephen On Sun, 9 Dec 2018 at 10:21, Gilles <[hidden email]> wrote: > Hello. > > After the discussion quote below, the conclusion was to go with > inheritance: > https://issues.apache.org/jira/browse/NUMBERS-80 > > However, it would make "Quaternion" fail the "ValJO" definition[1] > that mandates that all constructors be private. > > Would a protected constructor really be an issue? > [In the case of "Quaternion", the subclass constructor would only > perform additional validation (cf. below for details).] > > > Thanks, > Gilles > > [1] https://blog.joda.org/2014/03/valjos-value-java-objects.html > > On Mon, 03 Dec 2018 10:31:42 +0100, Gilles wrote: > > Hi. > > > > On Mon, 3 Dec 2018 03:56:02 +0000, Matt Juntunen wrote: > >> I was just thinking from a practical standpoint. My current > >> QuaternionRotation class is still in my working branch for > >> GEOMETRY-14 > >> and so isn't really accessible to anyone. If I can finish it up in > >> its > >> current state (hopefully very soon) and get it merged, then someone > >> else will be able to work with it and blend the functionality with > >> commons-numbers. > > > > Someone else? > > > >> > >> Here are some notes on your questions from before: > >> > >> * Should "QuaternionRotation" inherit from "Quaternion"? > >> > >> That would work conceptually. The quaternions in the > >> QuaternionRotation class are standard quaternions that meet two > >> other > >> criteria: 1) they are unit length, and 2) their scalar component is > >> greater than or equal to zero (in order to standardize the angles > >> involved). > > > > It seems indeed the perfect case for inheritance. > > > >> The one sticking point here is that I'm not sure how this > >> fits with the VALJO concept. If we can get this sorted, then this > >> very > >> well may be the best option. > > > > What do you see as a potential issue? > > > >> > >> * Should "Quaternion" be defined in [Geometry] (and removed from > >> [Numbers])? > >> > >> Perhaps. I've certainly only used them to represent 3D rotations. > >> Are > >> there any other use cases from commons-numbers? > > > > Not within [Numbers], but that's the point of those very low-level > > components/modules: they are common utilities used by higher-level > > components/libraries/applications. > > > > Given that "QuaternionRotation" is a special case of "Quaternion", > > it is logical to keep the latter at a lower-level, namely in > > [Numebers], and make [Geometry] depend on it. > > > >> > >> * Are some utilities defined in "QuaternionRotation" general > >> such that they could be part of the [Numbers] "Quaternion" API. > >> An example might be the transformation between quaternion and > >> matrix (represented as a double[3][3])? > >> > >> The conversion to rotation matrix and slerp are the best candidates > >> here. The other methods rely on core classes from commons-geometry, > >> namely Vector3D. > > > > Is "slerp" applicable to a general "Quaternion", or does it assume > > the additional requirements of "QuaternionRotation"? > > [Same question applies to all utilities in order to decide where to > > define them.] > > > >> > >> One more note: I decided to make a separate package for 3D rotations > >> in my working branch for GEOMETRY-14, so QuaternionRotation is now > >> at > >> > >> > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java > . > > > > Could you please update it so that it inherits from "Quaternion"? > > > > Thanks, > > Gilles > > > >> > >> -Matt > >> ________________________________ > >> From: Gilles <[hidden email]> > >> Sent: Sunday, December 2, 2018 3:57 PM > >> To: [hidden email] > >> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: > >> Making Quaternion a VALJO) > >> > >> On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: > >>> Unless anyone objects, I'm going to continue with what I'm working > >>> on > >> > >> I certainly don't object on your working to improve the geometry > >> code, but wherever that work overlaps with code being worked on > >> elsewhere (in this case, the "Quaternion" class), then we'd > >> rather have a discussion happening here first. > >> > >>> with QuaternionRotation and create a merge request. That way, we'll > >>> at > >>> least have a reference implementation and baseline functionality > >>> for > >>> commons-geometry that we can modify later based on what's decided > >>> here. > >> > >> My questions below are a start; I'm waiting for answers. > >> Code duplication is bad (TM). > >> > >> Regards, > >> Gilles > >> > >>> > >>> -Matt > >>> ________________________________ > >>> From: Gilles <[hidden email]> > >>> Sent: Saturday, December 1, 2018 9:40 PM > >>> To: [hidden email] > >>> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: > >>> Making Quaternion a VALJO) > >>> > >>> On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: > >>>> Hello. > >>>> > >>>> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: > >>>>> Hi guys, > >>>>> > >>>>> FYI, I've been working on a quaternion-related class named > >>>>> QuaternionRotation for commons-geometry (see link below). It > >>>>> includes > >>>>> slerp as well as several other geometry-oriented methods, such as > >>>>> conversion to/from axis-angle representations and creation from > >>>>> basis > >>>>> rotations. It's not quite ready for a merge yet since I still > >>>>> need > >>>>> to > >>>>> finish the Euler angle conversions. > >>>>> > >>>>> I did not use the Quaternion class from commons-numbers since I > >>>>> wanted to focus solely on using quaternions to represent 3D > >>>>> rotations. > >>>>> I felt like the commons-numbers class was too general for this. > >>>> > >>>> We need to explore further how to avoid duplication. > >>>> > >>>> Some questions: > >>>> * Should "QuaternionRotation" inherit from "Quaternion"? > >>>> * Should "Quaternion" be defined in [Geometry] (and removed from > >>>> [Numbers])? > >>>> * Are some utilities defined in "QuaternionRotation" general > >>>> such that they could be part of the [Numbers] "Quaternion" API. > >>>> An example might be the transformation between quaternion and > >>>> matrix (represented as a double[3][3])? > >>>> > >>>> The second consideration could apply to any computation that does > >>>> not require types defined in [Geometry]. For example, > >>>> interpolation > >>>> is a purely quaternion-internal operation. > >>> > >>> s/second/third/ > >>> > >>>> > >>>> It looks to me that it should be possible to come up with a design > >>>> that defines "rotation" in [Geometry] which uses a "quaternion" > >>>> defined in [Numbers]. > >>>> Otherwise, one would wonder why "Complex" is also not in > >>>> [Geometry] > >>>> (for 2D rotations). > >>>> > >>>> Best regards, > >>>> Gilles > >>>> > >>>>> > >>>>> Regards, > >>>>> Matt > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > >>>>> > >>>>> > >>>>> > >>>>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]< > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > > > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> darkma773r/commons-geometry< > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > > > >>>>> Apache Commons Geometry. Contribute to > >>>>> darkma773r/commons-geometry > >>>>> development by creating an account on GitHub. > >>>>> github.com > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> ________________________________ > >>>>> From: Gilles <[hidden email]> > >>>>> Sent: Friday, November 30, 2018 9:37 AM > >>>>> To: [hidden email] > >>>>> Subject: Re: [numbers] Making Quaternion a VALJO > >>>>> > >>>>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: > >>>>>>> > and I have also emailed an ICLA. > >>>>>> > >>>>>>> Not received/acknowledged yet. > >>>>>> > >>>>>> I am now listed on the "Persons with signed CLAs but who are not > >>>>>> (yet) > >>>>>> committers." page. > >>>>> > >>>>> Welcome! > >>>>> > >>>>>>> > I think two convenience divide methods performing qr^{-1} and > >>>>>>> r^{-1}q > >>>>>>> > for q > >>>>>>> > and r would be useful, but I couldn't think of nice names for > >>>>>>> them. > >>>>>> > >>>>>>> What are the use-cases? > >>>>>>> Why aren't "multiply" and "inverse" enough? > >>>>>> > >>>>>> I must admit I'm new to quaternions and stumbled into the > >>>>>> project > >>>>>> while > >>>>>> trying to improve my understanding so I'm not going to claim > >>>>>> great > >>>>>> knowledge of how common these operations are. I was primarily > >>>>>> thinking of > >>>>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that > >>>>>> you > >>>>>> end up > >>>>>> creating inverse instances and throwing them away a lot and I > >>>>>> thought > >>>>>> it > >>>>>> would be good to reduce that overhead. > >>>>> > >>>>> Surely, the class "Quaternion" is minimal but, before adding to > >>>>> the API, we be careful to have use-cases for low-level > >>>>> operations. > >>>>> Those mentioned above seems more high-level, tied to a specific > >>>>> domain (see also "Commons Geometry", another new component not > >>>>> yet > >>>>> released) but I may be wrong... > >>>>> > >>>>> Regards, > >>>>> Gilles > >>>>> > >>>>>> > >>>>>> Steve > >>>>> > >>>> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [hidden email] > For additional commands, e-mail: [hidden email] > > |
> On Dec 12, 2018, at 5:48 PM, Stephen Colebourne <[hidden email]> wrote: > > I think this has already been worked out, but the main reason for no > inheritance is that is probably blocks future conversion to value types. > Composition instead of inheritance is usually the right solution. +1 to that. > > Stephen > > >> On Sun, 9 Dec 2018 at 10:21, Gilles <[hidden email]> wrote: >> >> Hello. >> >> After the discussion quote below, the conclusion was to go with >> inheritance: >> https://issues.apache.org/jira/browse/NUMBERS-80 >> >> However, it would make "Quaternion" fail the "ValJO" definition[1] >> that mandates that all constructors be private. >> >> Would a protected constructor really be an issue? >> [In the case of "Quaternion", the subclass constructor would only >> perform additional validation (cf. below for details).] >> >> >> Thanks, >> Gilles >> >> [1] https://blog.joda.org/2014/03/valjos-value-java-objects.html >> >>> On Mon, 03 Dec 2018 10:31:42 +0100, Gilles wrote: >>> Hi. >>> >>>> On Mon, 3 Dec 2018 03:56:02 +0000, Matt Juntunen wrote: >>>> I was just thinking from a practical standpoint. My current >>>> QuaternionRotation class is still in my working branch for >>>> GEOMETRY-14 >>>> and so isn't really accessible to anyone. If I can finish it up in >>>> its >>>> current state (hopefully very soon) and get it merged, then someone >>>> else will be able to work with it and blend the functionality with >>>> commons-numbers. >>> >>> Someone else? >>> >>>> >>>> Here are some notes on your questions from before: >>>> >>>> * Should "QuaternionRotation" inherit from "Quaternion"? >>>> >>>> That would work conceptually. The quaternions in the >>>> QuaternionRotation class are standard quaternions that meet two >>>> other >>>> criteria: 1) they are unit length, and 2) their scalar component is >>>> greater than or equal to zero (in order to standardize the angles >>>> involved). >>> >>> It seems indeed the perfect case for inheritance. >>> >>>> The one sticking point here is that I'm not sure how this >>>> fits with the VALJO concept. If we can get this sorted, then this >>>> very >>>> well may be the best option. >>> >>> What do you see as a potential issue? >>> >>>> >>>> * Should "Quaternion" be defined in [Geometry] (and removed from >>>> [Numbers])? >>>> >>>> Perhaps. I've certainly only used them to represent 3D rotations. >>>> Are >>>> there any other use cases from commons-numbers? >>> >>> Not within [Numbers], but that's the point of those very low-level >>> components/modules: they are common utilities used by higher-level >>> components/libraries/applications. >>> >>> Given that "QuaternionRotation" is a special case of "Quaternion", >>> it is logical to keep the latter at a lower-level, namely in >>> [Numebers], and make [Geometry] depend on it. >>> >>>> >>>> * Are some utilities defined in "QuaternionRotation" general >>>> such that they could be part of the [Numbers] "Quaternion" API. >>>> An example might be the transformation between quaternion and >>>> matrix (represented as a double[3][3])? >>>> >>>> The conversion to rotation matrix and slerp are the best candidates >>>> here. The other methods rely on core classes from commons-geometry, >>>> namely Vector3D. >>> >>> Is "slerp" applicable to a general "Quaternion", or does it assume >>> the additional requirements of "QuaternionRotation"? >>> [Same question applies to all utilities in order to decide where to >>> define them.] >>> >>>> >>>> One more note: I decided to make a separate package for 3D rotations >>>> in my working branch for GEOMETRY-14, so QuaternionRotation is now >>>> at >>>> >>>> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java >> . >>> >>> Could you please update it so that it inherits from "Quaternion"? >>> >>> Thanks, >>> Gilles >>> >>>> >>>> -Matt >>>> ________________________________ >>>> From: Gilles <[hidden email]> >>>> Sent: Sunday, December 2, 2018 3:57 PM >>>> To: [hidden email] >>>> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: >>>> Making Quaternion a VALJO) >>>> >>>>> On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: >>>>> Unless anyone objects, I'm going to continue with what I'm working >>>>> on >>>> >>>> I certainly don't object on your working to improve the geometry >>>> code, but wherever that work overlaps with code being worked on >>>> elsewhere (in this case, the "Quaternion" class), then we'd >>>> rather have a discussion happening here first. >>>> >>>>> with QuaternionRotation and create a merge request. That way, we'll >>>>> at >>>>> least have a reference implementation and baseline functionality >>>>> for >>>>> commons-geometry that we can modify later based on what's decided >>>>> here. >>>> >>>> My questions below are a start; I'm waiting for answers. >>>> Code duplication is bad (TM). >>>> >>>> Regards, >>>> Gilles >>>> >>>>> >>>>> -Matt >>>>> ________________________________ >>>>> From: Gilles <[hidden email]> >>>>> Sent: Saturday, December 1, 2018 9:40 PM >>>>> To: [hidden email] >>>>> Subject: Re: [Numbers][Geometry] Where to define "quaternion" (Was: >>>>> Making Quaternion a VALJO) >>>>> >>>>>> On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: >>>>>> Hello. >>>>>> >>>>>>> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >>>>>>> Hi guys, >>>>>>> >>>>>>> FYI, I've been working on a quaternion-related class named >>>>>>> QuaternionRotation for commons-geometry (see link below). It >>>>>>> includes >>>>>>> slerp as well as several other geometry-oriented methods, such as >>>>>>> conversion to/from axis-angle representations and creation from >>>>>>> basis >>>>>>> rotations. It's not quite ready for a merge yet since I still >>>>>>> need >>>>>>> to >>>>>>> finish the Euler angle conversions. >>>>>>> >>>>>>> I did not use the Quaternion class from commons-numbers since I >>>>>>> wanted to focus solely on using quaternions to represent 3D >>>>>>> rotations. >>>>>>> I felt like the commons-numbers class was too general for this. >>>>>> >>>>>> We need to explore further how to avoid duplication. >>>>>> >>>>>> Some questions: >>>>>> * Should "QuaternionRotation" inherit from "Quaternion"? >>>>>> * Should "Quaternion" be defined in [Geometry] (and removed from >>>>>> [Numbers])? >>>>>> * Are some utilities defined in "QuaternionRotation" general >>>>>> such that they could be part of the [Numbers] "Quaternion" API. >>>>>> An example might be the transformation between quaternion and >>>>>> matrix (represented as a double[3][3])? >>>>>> >>>>>> The second consideration could apply to any computation that does >>>>>> not require types defined in [Geometry]. For example, >>>>>> interpolation >>>>>> is a purely quaternion-internal operation. >>>>> >>>>> s/second/third/ >>>>> >>>>>> >>>>>> It looks to me that it should be possible to come up with a design >>>>>> that defines "rotation" in [Geometry] which uses a "quaternion" >>>>>> defined in [Numbers]. >>>>>> Otherwise, one would wonder why "Complex" is also not in >>>>>> [Geometry] >>>>>> (for 2D rotations). >>>>>> >>>>>> Best regards, >>>>>> Gilles >>>>>> >>>>>>> >>>>>>> Regards, >>>>>>> Matt >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>>>>>> >>>>>>> >>>>>>> >>>>>>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]< >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> darkma773r/commons-geometry< >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >>> >>>>>>> Apache Commons Geometry. Contribute to >>>>>>> darkma773r/commons-geometry >>>>>>> development by creating an account on GitHub. >>>>>>> github.com >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> ________________________________ >>>>>>> From: Gilles <[hidden email]> >>>>>>> Sent: Friday, November 30, 2018 9:37 AM >>>>>>> To: [hidden email] >>>>>>> Subject: Re: [numbers] Making Quaternion a VALJO >>>>>>> >>>>>>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >>>>>>>>>> and I have also emailed an ICLA. >>>>>>>> >>>>>>>>> Not received/acknowledged yet. >>>>>>>> >>>>>>>> I am now listed on the "Persons with signed CLAs but who are not >>>>>>>> (yet) >>>>>>>> committers." page. >>>>>>> >>>>>>> Welcome! >>>>>>> >>>>>>>>>> I think two convenience divide methods performing qr^{-1} and >>>>>>>>> r^{-1}q >>>>>>>>>> for q >>>>>>>>>> and r would be useful, but I couldn't think of nice names for >>>>>>>>> them. >>>>>>>> >>>>>>>>> What are the use-cases? >>>>>>>>> Why aren't "multiply" and "inverse" enough? >>>>>>>> >>>>>>>> I must admit I'm new to quaternions and stumbled into the >>>>>>>> project >>>>>>>> while >>>>>>>> trying to improve my understanding so I'm not going to claim >>>>>>>> great >>>>>>>> knowledge of how common these operations are. I was primarily >>>>>>>> thinking of >>>>>>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me that >>>>>>>> you >>>>>>>> end up >>>>>>>> creating inverse instances and throwing them away a lot and I >>>>>>>> thought >>>>>>>> it >>>>>>>> would be good to reduce that overhead. >>>>>>> >>>>>>> Surely, the class "Quaternion" is minimal but, before adding to >>>>>>> the API, we be careful to have use-cases for low-level >>>>>>> operations. >>>>>>> Those mentioned above seems more high-level, tied to a specific >>>>>>> domain (see also "Commons Geometry", another new component not >>>>>>> yet >>>>>>> released) but I may be wrong... >>>>>>> >>>>>>> Regards, >>>>>>> Gilles >>>>>>> >>>>>>>> >>>>>>>> Steve >>>>>>> >>>>>> >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [hidden email] >> For additional commands, e-mail: [hidden email] >> >> --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
In reply to this post by jodastephen
Hi.
On Wed, 12 Dec 2018 22:48:54 +0000, Stephen Colebourne wrote: > I think this has already been worked out, but the main reason for no > inheritance is that is probably blocks future conversion to value > types. > Composition instead of inheritance is usually the right solution. Thanks for the reply. Do you think that the implementation here: https://gitbox.apache.org/repos/asf?p=commons-numbers.git;a=blob;f=commons-numbers-quaternion/src/main/java/org/apache/commons/numbers/quaternion/Quaternion.java still counts as ValJO, despite allowing (mandating even) inheritance by inner classes (as per your paragraph that ends with "The need for this is rare however.") What I don't quite see is the consequences of the class not being final... Gilles > > Stephen > > > On Sun, 9 Dec 2018 at 10:21, Gilles <[hidden email]> > wrote: > >> Hello. >> >> After the discussion quote below, the conclusion was to go with >> inheritance: >> https://issues.apache.org/jira/browse/NUMBERS-80 >> >> However, it would make "Quaternion" fail the "ValJO" definition[1] >> that mandates that all constructors be private. >> >> Would a protected constructor really be an issue? >> [In the case of "Quaternion", the subclass constructor would only >> perform additional validation (cf. below for details).] >> >> >> Thanks, >> Gilles >> >> [1] https://blog.joda.org/2014/03/valjos-value-java-objects.html >> >> On Mon, 03 Dec 2018 10:31:42 +0100, Gilles wrote: >> > Hi. >> > >> > On Mon, 3 Dec 2018 03:56:02 +0000, Matt Juntunen wrote: >> >> I was just thinking from a practical standpoint. My current >> >> QuaternionRotation class is still in my working branch for >> >> GEOMETRY-14 >> >> and so isn't really accessible to anyone. If I can finish it up >> in >> >> its >> >> current state (hopefully very soon) and get it merged, then >> someone >> >> else will be able to work with it and blend the functionality >> with >> >> commons-numbers. >> > >> > Someone else? >> > >> >> >> >> Here are some notes on your questions from before: >> >> >> >> * Should "QuaternionRotation" inherit from "Quaternion"? >> >> >> >> That would work conceptually. The quaternions in the >> >> QuaternionRotation class are standard quaternions that meet two >> >> other >> >> criteria: 1) they are unit length, and 2) their scalar component >> is >> >> greater than or equal to zero (in order to standardize the angles >> >> involved). >> > >> > It seems indeed the perfect case for inheritance. >> > >> >> The one sticking point here is that I'm not sure how this >> >> fits with the VALJO concept. If we can get this sorted, then this >> >> very >> >> well may be the best option. >> > >> > What do you see as a potential issue? >> > >> >> >> >> * Should "Quaternion" be defined in [Geometry] (and removed >> from >> >> [Numbers])? >> >> >> >> Perhaps. I've certainly only used them to represent 3D rotations. >> >> Are >> >> there any other use cases from commons-numbers? >> > >> > Not within [Numbers], but that's the point of those very low-level >> > components/modules: they are common utilities used by higher-level >> > components/libraries/applications. >> > >> > Given that "QuaternionRotation" is a special case of "Quaternion", >> > it is logical to keep the latter at a lower-level, namely in >> > [Numebers], and make [Geometry] depend on it. >> > >> >> >> >> * Are some utilities defined in "QuaternionRotation" general >> >> such that they could be part of the [Numbers] "Quaternion" >> API. >> >> An example might be the transformation between quaternion and >> >> matrix (represented as a double[3][3])? >> >> >> >> The conversion to rotation matrix and slerp are the best >> candidates >> >> here. The other methods rely on core classes from >> commons-geometry, >> >> namely Vector3D. >> > >> > Is "slerp" applicable to a general "Quaternion", or does it assume >> > the additional requirements of "QuaternionRotation"? >> > [Same question applies to all utilities in order to decide where >> to >> > define them.] >> > >> >> >> >> One more note: I decided to make a separate package for 3D >> rotations >> >> in my working branch for GEOMETRY-14, so QuaternionRotation is >> now >> >> at >> >> >> >> >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java >> . >> > >> > Could you please update it so that it inherits from "Quaternion"? >> > >> > Thanks, >> > Gilles >> > >> >> >> >> -Matt >> >> ________________________________ >> >> From: Gilles <[hidden email]> >> >> Sent: Sunday, December 2, 2018 3:57 PM >> >> To: [hidden email] >> >> Subject: Re: [Numbers][Geometry] Where to define "quaternion" >> (Was: >> >> Making Quaternion a VALJO) >> >> >> >> On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: >> >>> Unless anyone objects, I'm going to continue with what I'm >> working >> >>> on >> >> >> >> I certainly don't object on your working to improve the geometry >> >> code, but wherever that work overlaps with code being worked on >> >> elsewhere (in this case, the "Quaternion" class), then we'd >> >> rather have a discussion happening here first. >> >> >> >>> with QuaternionRotation and create a merge request. That way, >> we'll >> >>> at >> >>> least have a reference implementation and baseline functionality >> >>> for >> >>> commons-geometry that we can modify later based on what's >> decided >> >>> here. >> >> >> >> My questions below are a start; I'm waiting for answers. >> >> Code duplication is bad (TM). >> >> >> >> Regards, >> >> Gilles >> >> >> >>> >> >>> -Matt >> >>> ________________________________ >> >>> From: Gilles <[hidden email]> >> >>> Sent: Saturday, December 1, 2018 9:40 PM >> >>> To: [hidden email] >> >>> Subject: Re: [Numbers][Geometry] Where to define "quaternion" >> (Was: >> >>> Making Quaternion a VALJO) >> >>> >> >>> On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: >> >>>> Hello. >> >>>> >> >>>> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: >> >>>>> Hi guys, >> >>>>> >> >>>>> FYI, I've been working on a quaternion-related class named >> >>>>> QuaternionRotation for commons-geometry (see link below). It >> >>>>> includes >> >>>>> slerp as well as several other geometry-oriented methods, such >> as >> >>>>> conversion to/from axis-angle representations and creation >> from >> >>>>> basis >> >>>>> rotations. It's not quite ready for a merge yet since I still >> >>>>> need >> >>>>> to >> >>>>> finish the Euler angle conversions. >> >>>>> >> >>>>> I did not use the Quaternion class from commons-numbers since >> I >> >>>>> wanted to focus solely on using quaternions to represent 3D >> >>>>> rotations. >> >>>>> I felt like the commons-numbers class was too general for >> this. >> >>>> >> >>>> We need to explore further how to avoid duplication. >> >>>> >> >>>> Some questions: >> >>>> * Should "QuaternionRotation" inherit from "Quaternion"? >> >>>> * Should "Quaternion" be defined in [Geometry] (and removed >> from >> >>>> [Numbers])? >> >>>> * Are some utilities defined in "QuaternionRotation" general >> >>>> such that they could be part of the [Numbers] "Quaternion" >> API. >> >>>> An example might be the transformation between quaternion >> and >> >>>> matrix (represented as a double[3][3])? >> >>>> >> >>>> The second consideration could apply to any computation that >> does >> >>>> not require types defined in [Geometry]. For example, >> >>>> interpolation >> >>>> is a purely quaternion-internal operation. >> >>> >> >>> s/second/third/ >> >>> >> >>>> >> >>>> It looks to me that it should be possible to come up with a >> design >> >>>> that defines "rotation" in [Geometry] which uses a "quaternion" >> >>>> defined in [Numbers]. >> >>>> Otherwise, one would wonder why "Complex" is also not in >> >>>> [Geometry] >> >>>> (for 2D rotations). >> >>>> >> >>>> Best regards, >> >>>> Gilles >> >>>> >> >>>>> >> >>>>> Regards, >> >>>>> Matt >> >>>>> >> >>>>> >> >>>>> >> >>>>> >> >>>>> >> >>>>> >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >> >>>>> >> >>>>> >> >>>>> >> >>>>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]< >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >> > >> >>>>> >> >>>>> >> >>>>> >> >>>>> >> >>>>> darkma773r/commons-geometry< >> >> https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java >> > >> >>>>> Apache Commons Geometry. Contribute to >> >>>>> darkma773r/commons-geometry >> >>>>> development by creating an account on GitHub. >> >>>>> github.com >> >>>>> >> >>>>> >> >>>>> >> >>>>> >> >>>>> ________________________________ >> >>>>> From: Gilles <[hidden email]> >> >>>>> Sent: Friday, November 30, 2018 9:37 AM >> >>>>> To: [hidden email] >> >>>>> Subject: Re: [numbers] Making Quaternion a VALJO >> >>>>> >> >>>>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: >> >>>>>>> > and I have also emailed an ICLA. >> >>>>>> >> >>>>>>> Not received/acknowledged yet. >> >>>>>> >> >>>>>> I am now listed on the "Persons with signed CLAs but who are >> not >> >>>>>> (yet) >> >>>>>> committers." page. >> >>>>> >> >>>>> Welcome! >> >>>>> >> >>>>>>> > I think two convenience divide methods performing qr^{-1} >> and >> >>>>>>> r^{-1}q >> >>>>>>> > for q >> >>>>>>> > and r would be useful, but I couldn't think of nice names >> for >> >>>>>>> them. >> >>>>>> >> >>>>>>> What are the use-cases? >> >>>>>>> Why aren't "multiply" and "inverse" enough? >> >>>>>> >> >>>>>> I must admit I'm new to quaternions and stumbled into the >> >>>>>> project >> >>>>>> while >> >>>>>> trying to improve my understanding so I'm not going to claim >> >>>>>> great >> >>>>>> knowledge of how common these operations are. I was primarily >> >>>>>> thinking of >> >>>>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me >> that >> >>>>>> you >> >>>>>> end up >> >>>>>> creating inverse instances and throwing them away a lot and I >> >>>>>> thought >> >>>>>> it >> >>>>>> would be good to reduce that overhead. >> >>>>> >> >>>>> Surely, the class "Quaternion" is minimal but, before adding >> to >> >>>>> the API, we be careful to have use-cases for low-level >> >>>>> operations. >> >>>>> Those mentioned above seems more high-level, tied to a >> specific >> >>>>> domain (see also "Commons Geometry", another new component not >> >>>>> yet >> >>>>> released) but I may be wrong... >> >>>>> >> >>>>> Regards, >> >>>>> Gilles >> >>>>> >> >>>>>> >> >>>>>> Steve >> >>>>> >> >>>> >> >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [hidden email] >> For additional commands, e-mail: [hidden email] >> >> --------------------------------------------------------------------- To unsubscribe, e-mail: [hidden email] For additional commands, e-mail: [hidden email] |
I can see the paragraph I wrote way back when, but I'd disagree with myself
now. To be a VALJO you can't be abstract nor have subclasses, even a closed set. I say this on the basis that AFAICT, future value types will also have the same restrictions. That said, VALJO rules are intended as a guide to best practice that may be beneficial when value types arrive. I don't think the code you've got is fundamentally wrong - its a reasonable way to share logic. An alternative would be an enum `QuaternianType` that has methods. final class Quaternion { private final QuaternionType type; private final double w; private final double x; private final double y; private final double z; public double norm() { return type.norm(w, x, y, z); } public double normSq() { return type.norm(w, x, y, z); } // and so on } By delegating the methods via the type enum, you get flexible behaviour without subclass. Stephen On Wed, 12 Dec 2018 at 23:20, Gilles <[hidden email]> wrote: > Hi. > > On Wed, 12 Dec 2018 22:48:54 +0000, Stephen Colebourne wrote: > > I think this has already been worked out, but the main reason for no > > inheritance is that is probably blocks future conversion to value > > types. > > Composition instead of inheritance is usually the right solution. > > Thanks for the reply. > > Do you think that the implementation here: > > > https://gitbox.apache.org/repos/asf?p=commons-numbers.git;a=blob;f=commons-numbers-quaternion/src/main/java/org/apache/commons/numbers/quaternion/Quaternion.java > still counts as ValJO, despite allowing (mandating even) inheritance > by inner classes (as per your paragraph that ends with "The need for > this is rare however.") > > What I don't quite see is the consequences of the class not being > final... > > > Gilles > > > > > Stephen > > > > > > On Sun, 9 Dec 2018 at 10:21, Gilles <[hidden email]> > > wrote: > > > >> Hello. > >> > >> After the discussion quote below, the conclusion was to go with > >> inheritance: > >> https://issues.apache.org/jira/browse/NUMBERS-80 > >> > >> However, it would make "Quaternion" fail the "ValJO" definition[1] > >> that mandates that all constructors be private. > >> > >> Would a protected constructor really be an issue? > >> [In the case of "Quaternion", the subclass constructor would only > >> perform additional validation (cf. below for details).] > >> > >> > >> Thanks, > >> Gilles > >> > >> [1] https://blog.joda.org/2014/03/valjos-value-java-objects.html > >> > >> On Mon, 03 Dec 2018 10:31:42 +0100, Gilles wrote: > >> > Hi. > >> > > >> > On Mon, 3 Dec 2018 03:56:02 +0000, Matt Juntunen wrote: > >> >> I was just thinking from a practical standpoint. My current > >> >> QuaternionRotation class is still in my working branch for > >> >> GEOMETRY-14 > >> >> and so isn't really accessible to anyone. If I can finish it up > >> in > >> >> its > >> >> current state (hopefully very soon) and get it merged, then > >> someone > >> >> else will be able to work with it and blend the functionality > >> with > >> >> commons-numbers. > >> > > >> > Someone else? > >> > > >> >> > >> >> Here are some notes on your questions from before: > >> >> > >> >> * Should "QuaternionRotation" inherit from "Quaternion"? > >> >> > >> >> That would work conceptually. The quaternions in the > >> >> QuaternionRotation class are standard quaternions that meet two > >> >> other > >> >> criteria: 1) they are unit length, and 2) their scalar component > >> is > >> >> greater than or equal to zero (in order to standardize the angles > >> >> involved). > >> > > >> > It seems indeed the perfect case for inheritance. > >> > > >> >> The one sticking point here is that I'm not sure how this > >> >> fits with the VALJO concept. If we can get this sorted, then this > >> >> very > >> >> well may be the best option. > >> > > >> > What do you see as a potential issue? > >> > > >> >> > >> >> * Should "Quaternion" be defined in [Geometry] (and removed > >> from > >> >> [Numbers])? > >> >> > >> >> Perhaps. I've certainly only used them to represent 3D rotations. > >> >> Are > >> >> there any other use cases from commons-numbers? > >> > > >> > Not within [Numbers], but that's the point of those very low-level > >> > components/modules: they are common utilities used by higher-level > >> > components/libraries/applications. > >> > > >> > Given that "QuaternionRotation" is a special case of "Quaternion", > >> > it is logical to keep the latter at a lower-level, namely in > >> > [Numebers], and make [Geometry] depend on it. > >> > > >> >> > >> >> * Are some utilities defined in "QuaternionRotation" general > >> >> such that they could be part of the [Numbers] "Quaternion" > >> API. > >> >> An example might be the transformation between quaternion and > >> >> matrix (represented as a double[3][3])? > >> >> > >> >> The conversion to rotation matrix and slerp are the best > >> candidates > >> >> here. The other methods rely on core classes from > >> commons-geometry, > >> >> namely Vector3D. > >> > > >> > Is "slerp" applicable to a general "Quaternion", or does it assume > >> > the additional requirements of "QuaternionRotation"? > >> > [Same question applies to all utilities in order to decide where > >> to > >> > define them.] > >> > > >> >> > >> >> One more note: I decided to make a separate package for 3D > >> rotations > >> >> in my working branch for GEOMETRY-14, so QuaternionRotation is > >> now > >> >> at > >> >> > >> >> > >> > >> > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/rotation/QuaternionRotation.java > >> . > >> > > >> > Could you please update it so that it inherits from "Quaternion"? > >> > > >> > Thanks, > >> > Gilles > >> > > >> >> > >> >> -Matt > >> >> ________________________________ > >> >> From: Gilles <[hidden email]> > >> >> Sent: Sunday, December 2, 2018 3:57 PM > >> >> To: [hidden email] > >> >> Subject: Re: [Numbers][Geometry] Where to define "quaternion" > >> (Was: > >> >> Making Quaternion a VALJO) > >> >> > >> >> On Sun, 2 Dec 2018 19:20:03 +0000, Matt Juntunen wrote: > >> >>> Unless anyone objects, I'm going to continue with what I'm > >> working > >> >>> on > >> >> > >> >> I certainly don't object on your working to improve the geometry > >> >> code, but wherever that work overlaps with code being worked on > >> >> elsewhere (in this case, the "Quaternion" class), then we'd > >> >> rather have a discussion happening here first. > >> >> > >> >>> with QuaternionRotation and create a merge request. That way, > >> we'll > >> >>> at > >> >>> least have a reference implementation and baseline functionality > >> >>> for > >> >>> commons-geometry that we can modify later based on what's > >> decided > >> >>> here. > >> >> > >> >> My questions below are a start; I'm waiting for answers. > >> >> Code duplication is bad (TM). > >> >> > >> >> Regards, > >> >> Gilles > >> >> > >> >>> > >> >>> -Matt > >> >>> ________________________________ > >> >>> From: Gilles <[hidden email]> > >> >>> Sent: Saturday, December 1, 2018 9:40 PM > >> >>> To: [hidden email] > >> >>> Subject: Re: [Numbers][Geometry] Where to define "quaternion" > >> (Was: > >> >>> Making Quaternion a VALJO) > >> >>> > >> >>> On Sat, 01 Dec 2018 12:56:34 +0100, Gilles wrote: > >> >>>> Hello. > >> >>>> > >> >>>> On Sat, 1 Dec 2018 06:05:31 +0000, Matt Juntunen wrote: > >> >>>>> Hi guys, > >> >>>>> > >> >>>>> FYI, I've been working on a quaternion-related class named > >> >>>>> QuaternionRotation for commons-geometry (see link below). It > >> >>>>> includes > >> >>>>> slerp as well as several other geometry-oriented methods, such > >> as > >> >>>>> conversion to/from axis-angle representations and creation > >> from > >> >>>>> basis > >> >>>>> rotations. It's not quite ready for a merge yet since I still > >> >>>>> need > >> >>>>> to > >> >>>>> finish the Euler angle conversions. > >> >>>>> > >> >>>>> I did not use the Quaternion class from commons-numbers since > >> I > >> >>>>> wanted to focus solely on using quaternions to represent 3D > >> >>>>> rotations. > >> >>>>> I felt like the commons-numbers class was too general for > >> this. > >> >>>> > >> >>>> We need to explore further how to avoid duplication. > >> >>>> > >> >>>> Some questions: > >> >>>> * Should "QuaternionRotation" inherit from "Quaternion"? > >> >>>> * Should "Quaternion" be defined in [Geometry] (and removed > >> from > >> >>>> [Numbers])? > >> >>>> * Are some utilities defined in "QuaternionRotation" general > >> >>>> such that they could be part of the [Numbers] "Quaternion" > >> API. > >> >>>> An example might be the transformation between quaternion > >> and > >> >>>> matrix (represented as a double[3][3])? > >> >>>> > >> >>>> The second consideration could apply to any computation that > >> does > >> >>>> not require types defined in [Geometry]. For example, > >> >>>> interpolation > >> >>>> is a purely quaternion-internal operation. > >> >>> > >> >>> s/second/third/ > >> >>> > >> >>>> > >> >>>> It looks to me that it should be possible to come up with a > >> design > >> >>>> that defines "rotation" in [Geometry] which uses a "quaternion" > >> >>>> defined in [Numbers]. > >> >>>> Otherwise, one would wonder why "Complex" is also not in > >> >>>> [Geometry] > >> >>>> (for 2D rotations). > >> >>>> > >> >>>> Best regards, > >> >>>> Gilles > >> >>>> > >> >>>>> > >> >>>>> Regards, > >> >>>>> Matt > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> > >> > >> > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> [https://avatars1.githubusercontent.com/u/3809623?s=400&v=4]< > >> > >> > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > >> > > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> darkma773r/commons-geometry< > >> > >> > https://github.com/darkma773r/commons-geometry/blob/transforms/commons-geometry-euclidean/src/main/java/org/apache/commons/geometry/euclidean/threed/QuaternionRotation.java > >> > > >> >>>>> Apache Commons Geometry. Contribute to > >> >>>>> darkma773r/commons-geometry > >> >>>>> development by creating an account on GitHub. > >> >>>>> github.com > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> > >> >>>>> ________________________________ > >> >>>>> From: Gilles <[hidden email]> > >> >>>>> Sent: Friday, November 30, 2018 9:37 AM > >> >>>>> To: [hidden email] > >> >>>>> Subject: Re: [numbers] Making Quaternion a VALJO > >> >>>>> > >> >>>>> On Fri, 30 Nov 2018 14:22:45 +0000, Steve Bosman wrote: > >> >>>>>>> > and I have also emailed an ICLA. > >> >>>>>> > >> >>>>>>> Not received/acknowledged yet. > >> >>>>>> > >> >>>>>> I am now listed on the "Persons with signed CLAs but who are > >> not > >> >>>>>> (yet) > >> >>>>>> committers." page. > >> >>>>> > >> >>>>> Welcome! > >> >>>>> > >> >>>>>>> > I think two convenience divide methods performing qr^{-1} > >> and > >> >>>>>>> r^{-1}q > >> >>>>>>> > for q > >> >>>>>>> > and r would be useful, but I couldn't think of nice names > >> for > >> >>>>>>> them. > >> >>>>>> > >> >>>>>>> What are the use-cases? > >> >>>>>>> Why aren't "multiply" and "inverse" enough? > >> >>>>>> > >> >>>>>> I must admit I'm new to quaternions and stumbled into the > >> >>>>>> project > >> >>>>>> while > >> >>>>>> trying to improve my understanding so I'm not going to claim > >> >>>>>> great > >> >>>>>> knowledge of how common these operations are. I was primarily > >> >>>>>> thinking of > >> >>>>>> Quaternion Interpolation - SLERP and SQUAD. It seems to me > >> that > >> >>>>>> you > >> >>>>>> end up > >> >>>>>> creating inverse instances and throwing them away a lot and I > >> >>>>>> thought > >> >>>>>> it > >> >>>>>> would be good to reduce that overhead. > >> >>>>> > >> >>>>> Surely, the class "Quaternion" is minimal but, before adding > >> to > >> >>>>> the API, we be careful to have use-cases for low-level > >> >>>>> operations. > >> >>>>> Those mentioned above seems more high-level, tied to a > >> specific > >> >>>>> domain (see also "Commons Geometry", another new component not > >> >>>>> yet > >> >>>>> released) but I may be wrong... > >> >>>>> > >> >>>>> Regards, > >> >>>>> Gilles > >> >>>>> > >> >>>>>> > >> >>>>>> Steve > >> >>>>> > >> >>>> > >> > >> > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: [hidden email] > >> For additional commands, e-mail: [hidden email] > >> > >> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [hidden email] > For additional commands, e-mail: [hidden email] > > |
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