[sharingmakesmesleepy]time warp


    Sep 18 2007 | 12:08 am
    Hi Guys, In the spirit of sharing wacky shader ephemera that has been circulating of late, here is a little sketch I've made of doing time-warping using a 3D texture and shader. Unfortunately, there is no feature currently exposed in Jitter to update a single slice of a 3D texture, so loading the texture to GPU is gonna be suuuuuuuper sloooooww, but once it's there should be ready to do the goo dance in fast motion.
    Happy patching.
    Andrew B.

    • Sep 18 2007 | 2:09 am
      web forum love?
    • Sep 18 2007 | 4:45 am
      Sorry again... For some reason I keep forgetting about the attachment limitations. Here is the ZIP again, this time attached using the web-forum. I'll try to remember next time, I promise.
      AB
    • Sep 18 2007 | 5:46 am
      ha ha! i knew you loved us. great example of use of 3d textures. i iz learning slowly.
      quick question. in gridshape you specify two values for the texture attribute, the two gl.texture names. how do you distinguish between the two in the shader? i know in this case, one is 2drect and one is 3d, but what if you had two textures of the same dimension. how does the shader know which is which?
      thanks again. -rob
    • Sep 18 2007 | 5:55 am
      Determining which texture gets where in a shader isn't discriminated by type. You can bind one type to a different sampler and things will just go blank. It's done my the uniform's name and which texture unit it's assigned to. In Jitter, this is handled by giving it a default int value :
      if you have jit.gl.gridshape foo @texture zebra monkey, zebra will be texo and monkey will be texa.
      wes
    • Sep 18 2007 | 6:01 am
      > how do you distinguish between the two in the shader? > i know in this case, one is 2drect and one is 3d, but what if you had two textures of the same dimension. how does the shader know which is which? > > Hi Rob, The @texture can have multiple arguments, which allows one to do multi-texturing. Within the shader .jxs file, you may notice that the 2 textures are bound as "int" params, with the values 0 and 1 respectively. The first argument to the @texture is texture 0, and the second is texture 1. These are then referred to within the shader as sampler__ types with the name given in the param binding XML code.
      Andrew B.
    • Sep 18 2007 | 6:02 am
      so based on the left to right order of the attribute values, which corresponds to the default value you set in the jxf?
      [gridshape foo @texture texone textwo texthree]
      in this case texone is texo, textwo is texa and texthree is texb.
      works for me. thanks for the clarification.
    • Sep 18 2007 | 2:14 pm
      I'm getting a bogus object: jit.gl.slab.gauss6x foo What is the intention there? not quite sure what I should substitute!
    • Sep 18 2007 | 3:08 pm
      Hi Peter, This is an abstraction that lives in the /examples/jitter-examples/render/slab folder. You probably removed the examples folder from your search path. The purpose of this abstraction is to perform a smooth gaussian blur on the map texture so that the time warp is smooth and interpolated.
      Andrew
    • Apr 15 2008 | 1:31 am
      Time warp has always worked on computer just fine, but now I'm trying to use it on another computer and I'm getting:
      jit.gl.render: building GL on window "zzzz"... jit.gl.texture: error submitting texture data: GL Error: Invalid value
      Then if I resend the 3d matrix to the slop texture I get:
      jit.gl.texture: setting teximage during submission.: GL Error: Invalid value
      This computer is a 2GHz Macbook with 2GB of RAM. GMA X3100 with 144MB of VRAM. 10.5.1 Max 4.6.3 Jitter 1.6.3
      Any help with this would be really great.
      Thanks, Keith On Mon, Sep 17, 2007 at 7:08 PM, andrew benson wrote:
      > Hi Guys, > In the spirit of sharing wacky shader ephemera that has been circulating > of late, here is a little sketch I've made of doing time-warping using a 3D > texture and shader. Unfortunately, there is no feature currently exposed in > Jitter to update a single slice of a 3D texture, so loading the texture to > GPU is gonna be suuuuuuuper sloooooww, but once it's there should be ready > to do the goo dance in fast motion. > > Happy patching. > > Andrew B. > > > >
    • Aug 22 2011 | 6:11 pm
      Is it possible to know where i can find the patch? thanks in advance :)
    • Aug 26 2011 | 6:57 am
      wouldn't it be this ?
    • Oct 19 2011 | 10:19 pm
      thanks! :)