[GEM-dev] glsl question

[jack at rybn.org]

Hello Erich,

No problem here on MacOSX.5.8 with pd-ext 0.41.4 and GEM 0.91.3 'tigital'.
My graphic card here : ATI Radeon HD 2600 Pro
What is your graphic card ?
Do you have errors in Pd console ?

[glsl_program]: uvar#0: "MyTex": [glsl_program]: unknown (0x8B5E)
[glsl_program]: uvar#1: "cr": [glsl_program]: GL_FLOAT
[glsl_program]: uvar#2: "cg": [glsl_program]: GL_FLOAT
[glsl_program]: uvar#3: "cb": [glsl_program]: GL_FLOAT
[glsl_program]: uvar#4: "gl_ModelViewProjectionMatrix": [glsl_program]:
GL_FLOAT_MAT4_ARB

Here my patch where you need to change the messages cr, cg, cb.
I use your vertex shader and the fragment shader with 'gl_FragColor =  C;'
++

Jack



> hello,
>
> i changed the fetching.vert shader so that i would be able to
> access rgb individually for shifting the vertices,
> but the result does not suggest that.
>
> is
>   vec4 color = texture2D(MyTex, gl_MultiTexCoord0.st)
> not a vector with RGBA of a single vertex ?
>
> best
>
> erich
>
>
> here the shader:
>
> uniform float cr, cg, cb;
> uniform sampler2D MyTex;
> varying vec4 C;
> void main()
> {
> 	vec4 v = vec4(gl_Vertex);
> 	vec4 color = texture2D(MyTex, gl_MultiTexCoord0.st);
> 	v.z = color.r*cr + color.g*cg +color.b*cb;
> //	v.x += (color.b-0.5)/2.;
> //	v.y += (color.g-0.5)/2.;
>
> 	C=color;
> 	gl_Position = gl_ModelViewProjectionMatrix * v;
>
> }
>
>
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>
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