November 2008 - FieldTrip

Re: [HOpenGL] noticing freeglut vs not
by Conal Elliott 07 Dec '08

07 Dec '08

Thanks for the pointers. I'm looking for some way to program my library so that a graceful exit is made where possible and still runs, though exits less gracefully with non-free glut. I'd be happy with either a new API entry for that case or a change to the meaning of MainLoopReturns. - Conal On Thu, Nov 20, 2008 at 5:33 AM, Sven Panne <sven.panne(a)aedion.de> wrote: > On Thursday 13 November 2008 03:24:29 Conal Elliott wrote: > > I'm looking for a way to use MainLoopReturns when freeglut is present and > > not when it isn't. I could use some help. I figure that the > > implementation has some way to generate that error message, and maybe we > > could similarly just do a standard ungraceful exit if freeglut is > missing. > > > > The great thing about MainLoopReturns is that it plays nicely with ghci. > > Closing a window returns to ghci for more fun. > > > > Some more info at http://trac.haskell.org/FieldTrip/ticket/8 . > > > > Any ideas? > > Currently the GLUT binding uses dynamic lookup to get freeglut-only API > entries (see /GLUT/Graphics/UI/GLUT/Extensions.hs, cbits/HsGLUT.c, > include/HsGLUTExt.h) and uses throwIfNull to test for non-existent API > entries. Therefore, e.g. actionOnWindowClose should throw an exception when > "classic" GLUT is used. I am not sure if I understand your request: Do you > want a new API entry for the GLUT binding or a different behavior of the > current entries? > > Cheers, > S. > >

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Re: [reactive] Transforming Behaviors
by Conal Elliott 25 Nov '08

25 Nov '08

The instances would get added to the reactive-fieldtrip package. That package is currently very small, but I anticipate lots of goodies going in that relate to the combined use of Reactive and FieldTrip. On Mon, Nov 24, 2008 at 11:18 AM, Conal Elliott <conal(a)conal.net> wrote: > Hi Greg, > > I don't think anyone has implemented an instance for static transformations > of dynamic geometry. Ought to be easy, though. Also dynamic transformation > of static geometry and dynamic transformation of dynamic geometry. And the > corresponding three additional instances for 2D geometry. All six would be > very useful. > > So I don't forget, would you please submit a ticket to either > http://trac.haskell.org/reactive or http://trac.haskell.org/FieldTrip ? > > You might also enjoy adding these instances yourself. Patches are very > welcome. > > Thanks, - Conal > > > On Mon, Nov 24, 2008 at 10:27 AM, Greg Fitzgerald <garious(a)gmail.com>wrote: > >> Should it be possible to write this: >> >> spinningTorusPair :: Double -> Behavior Geometry3 >> spinningTorusPair sz = uscale3 sz *% spinningG torusPair >> >> Instead of this: >> >> spinningTorusPair :: Double -> Behavior Geometry3 >> spinningTorusPair sz = (uscale3 sz *%) <$> spinningG torusPair >> >> >> That is, should a Behavior of something transformable be an instance >> of Transform as well? Has anyone tried to implement this instance? >> >> Thanks, >> Greg >> _______________________________________________ >> Reactive mailing list >> Reactive(a)haskell.org >> http://www.haskell.org/mailman/listinfo/reactive >> > >

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Re: [reactive] Google group for the mailing list
by Conal Elliott 18 Nov '08

18 Nov '08

Thanks Eyal. I've just done the same for the FieldTrip group. On Tue, Nov 18, 2008 at 10:35 AM, eyal.lotem(a)gmail.com <eyal.lotem(a)gmail.com > wrote: > You might prefer to use the > http://groups.google.com/group/reactive-haskell/ > URL to read the reactive mailing list, or to post messages. > > It does the archiving for you, and lets you post via a web form. > _______________________________________________ > Reactive mailing list > Reactive(a)haskell.org > http://www.haskell.org/mailman/listinfo/reactive >

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Handles to GPU-Resources
by Andreas-Christoph Bernstein 13 Nov '08

13 Nov '08

Hi, Yesterday i played a bit with reactive-fieldtrip and it is a lot of fun. What are the future plans to deal with handles to gpu data, like texture, shader, and buffer objects ? Because i thought it might be a good idea to use vertex buffer objects for the geometry since with OpenGL 3.0 the glBegin/glEnd (and much more) is obsolete. So i built data types for a static vertex buffer object and a static index buffer object and made them an instance of Renderable. What the thing is, is that i can create the bufferobject only after the creation of the OpenGL context. That's why i use unsafePerformIO as i have seen in an obj file example. > vboGeom :: Geometry3 > vboGeom = renderableG geom > where > geom = unsafePerformIO $ loadVbo cubeVertexData cubeTriIndices Not very elegant. So are there any ideas on that ? Btw, i could post the functions and data types for my vertex buffer example if anyone likes to see them. kind regards, Andreas -- Andreas-C. Bernstein Virtual Reality Systems Group Faculty of Media Bauhaus-Universitaet Weimar Bauhausstraße 11 (Room 118) 99423 Weimar Germany phone: +49 3643 - 58 3734 fax : +49 3643 - 58 3709 email: andreas.bernstein(a)medien.uni-weimar.de web : www.uni-weimar.de/medien/vr

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noticing freeglut vs not
by Conal Elliott 12 Nov '08

12 Nov '08

I'm looking for a way to use MainLoopReturns when freeglut is present and not when it isn't. I could use some help. I figure that the implementation has some way to generate that error message, and maybe we could similarly just do a standard ungraceful exit if freeglut is missing. The great thing about MainLoopReturns is that it plays nicely with ghci. Closing a window returns to ghci for more fun. Some more info at http://trac.haskell.org/FieldTrip/ticket/8 . Any ideas? Thanks, - Conal

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FieldTrip trac rename
by Conal Elliott 12 Nov '08

12 Nov '08

The FieldTrip bug/feature tracker is now at http://trac.haskell.org/FieldTrip/ (minor rename). Please do report problems & suggestions as you have them. I'd love for FieldTrip to be fun & useful for all, and I could use the help. - Conal

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Re: [reactive] reactive-fieldtrip
by Conal Elliott 11 Nov '08

11 Nov '08

Hi Eyal, Thanks for the comments. I'm replying on the FieldTrip list rather than on reactive, since the issues are mostly FieldTrip issues. On Tue, Nov 11, 2008 at 7:24 AM, Eyal Lotem <eyal.lotem(a)gmail.com> wrote: > Hi > > I would also like to congratulate Conal and everyone else involved in > the Reactive framework and libraries for the new release. Amazing > work! > > I have finally managed to do more than read about it, and actually toy > with some Reactive programming :-) > It seems great fun, and the learning curve is not as steep as it might > seem at first. > > I mostly played with Test.hs inside the reactive-fieldtrip adapter, > and I have encountered a few issues: > > A. It seems that when changing spinningG to scale according to time, > it becomes extremely slow very quickly. Probably because of the current algorithm for dynamic tessellation (approximation by polygons). As you scale up, a surface will get tessellated more and more finely during rendering. The tessellations are cached in an efficient, infinite, pure data structure (a MemoTrie) as they're computed. Given your experience, I gather there's some tuning required. > B. The lplace demo itself is also extremely slow, whereas other demos > seem to be fine/quick. It might be buggy, and not extremely slow, its > taking so long to react that I am not sure what is happening. All of the demos are *very* zippy on my machine, even with 10-20 spinning torus pairs going. Could you please give me particulars about your setup? For instance: cpu(s), graphics card, OS, and versions of opengl & glut. C. Stylistic question/comment: > The (Anim a) type (UI -> Behavior a) is a Reader > Functor/Applicative/Monad. I see it used as a Functor in various > examples, but it seems that there's no use of the Applicative/Monad of > the reader, is this intentional? > I find it a bit awkward that it passes the "env" arg to all of the > stuff its combining... The example even used an undefined error value > in place of the env in some cases, suggesting that it is a burden to > pass it around. Why not encourage the implicit passing of the env > everywhere via the reader Applicative? > Fixed now. Thanks. Regards, - Conal

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oops -- obsolete examples in FieldTrip
by Conal Elliott 11 Nov '08

11 Nov '08

There was an obsolete examples/ directory in the FieldTrip release, including examples/Test.hs. I've removed that directory in the latest version and tidied up the examples a bit. You can run try out FieldTrip via the reactive-fieldtrip package, as described on http://haskell.org/haskellwiki/FieldTrip . - Conal

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oops -- obsolete examples in FieldTrip
by Conal Elliott 11 Nov '08

11 Nov '08

There was an obsolete examples/ directory in the FieldTrip release, including examples/Test.hs. I've removed that directory in the latest version and tidied up the examples a bit. You can run try out FieldTrip via the reactive-fieldtrip package, as described on http://haskell.org/haskellwiki/FieldTrip . - Conal

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Re: [Haskell-cafe] Announce: FieldTrip library (functional 3D) and mailing list
by Conal Elliott 10 Nov '08

10 Nov '08

Thanks for the prod, Andrew. (And thanks to Don S for prodding yesterday.) Now there's a picture on the FieldTrip page [1]. The shading is done using normals generated via derivatives from the vector-space package [2]. [1] http://haskell.org/haskellwiki/FieldTrip [2] http://haskell.org/haskellwiki/vector-space - Conal On Mon, Nov 10, 2008 at 10:27 AM, Andrew Coppin <andrewcoppin(a)btinternet.com > wrote: > Conal Elliott wrote: > >> FieldTrip [1] is a library for functional 3D graphics. It is intended for >> building static, animated, and interactive 3D geometry, efficient enough for >> real-time synthesis and display. Since FieldTrip is functional, one >> describes what models are, not how to render them (being rather than doing). >> >> Surfaces are described as functions from 2D space to 3D space. As such, >> they are intrinsically curved rather than faceted. Surface rendering >> tessellates adaptively, caching tessellations in an efficient, infinite data >> structure (from the MemoTrie library) for reuse. Surface normals are >> computed automatically and exactly, using the derivative tools in the >> vector-space library. >> >> For animation or interaction, FieldTrip can be used with the Reactive [2] >> library for functional reactive programming (and possibly other animation >> frameworks). By design, FieldTrip is completely orthogonal to any >> formulation or implementation of FRP. The reactive-fieldtrip [3] library >> links Reactive and FieldTrip. >> >> FieldTrip now has a mailing list [4] and a feature/bug tracker [5]. >> > > Sounds very interesting, but... what, no pictures? From a library > especially designed for generating pictures? :-) > >

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