I'm trying to troubleshoot some issues between nVidia and ATI.  nVidia is currently working fine, but my test ATI card (x1300) is having issues with point sprites.  I've updated to the latest driver and made many changes... perhaps someone could help and take a look.

Windows / ATI card is rendering the colors wrong and the texture is upside down.  Again, works fine on my MacBook (nVidia).

Vertex Shader

1. uniform float pointSize;
2. uniform float gui;
3. varying vec4 vFragColor;
4. void main(void) {
5.     gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
6.     vec4 modv = vec4( gl_ModelViewMatrix * gl_Vertex );
7.     if(gui == 0.0) {
8.         gl_PointSize = 200.0 * pointSize/ -modv.z ;
9.     } else {
10.         gl_PointSize = pointSize;
11.     }
12.     float fog = 8000.0/ -modv.z;
13.     if (fog < 8.0 && gui == 0.0) {
14.          vFragColor = smoothstep(0.0, 8.0, fog) * gl_Color;
15.     } else {
16.         vFragColor = gl_Color;
17.     }
18.     gl_FrontColor = gl_Color;
19.     gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
20. }

Fragment Shader

1. uniform sampler2D tex;
2. varying vec4 vFragColor;
3. void main() {
4.     vec4 color = texture2D(tex, gl_TexCoord[0].st);
5.     gl_FragColor = color * vFragColor;
6. }

Processing Code

1.  try {
       ringImg = TextureIO.newTexture(new File(dataPath("images" + File.separator + "ring2.png")), true);
     }
     catch (IOException e) {   
       showMessage(e);
     }
   
2. ...
3.       pshader.startShader();
4.         gl.glUniform1f(pshader.getUniformLocation("gui"), 0.0);
5.         gl.glDisable(GL.GL_POINT_SMOOTH);
6.         gl.glEnable(GL.GL_POINT_SPRITE_ARB);
7.         gl.glEnableClientState(GL.GL_VERTEX_ARRAY);
8.         gl.glEnableClientState(GL.GL_COLOR_ARRAY);
9.         gl.glEnable(GL.GL_VERTEX_PROGRAM_POINT_SIZE_ARB);
10.         gl.glPointParameterfARB( GL.GL_POINT_SIZE_MIN_ARB, 0.0 );
11.         gl.glTexEnvi(GL.GL_POINT_SPRITE_ARB, GL.GL_COORD_REPLACE_ARB, GL.GL_TRUE);
12.           gl.glBlendFunc(GL.GL_ONE,GL.GL_ONE_MINUS_SRC_ALPHA);
13.           ringImg.enable();
14.           ringImg.bind();
15.           gl.glUniform1f(pshader.getUniformLocation("pointSize"), 114.0);
16.           gl.glBindBuffer( GL.GL_ARRAY_BUFFER,  nodes_vbo[0]);
17.           gl.glVertexPointer(3,GL.GL_FLOAT,0,0);
18.           gl.glBindBuffer( GL.GL_ARRAY_BUFFER, nodes_vbo[1] );
19.           gl.glColorPointer(3,GL.GL_FLOAT,0,0);
20.           gl.glBindBuffer( GL.GL_ELEMENT_ARRAY_BUFFER, nelements_vbo[0] );
21.           gl.glDrawElements( GL.GL_POINTS, vnodelength, GL.GL_UNSIGNED_INT, 0 );
22.           gl.glDisableClientState(GL.GL_COLOR_ARRAY);
23.           ringImg.disable();
24.         gl.glDisable(GL.GL_POINT_SPRITE_ARB);
25.         gl.glUniform1f(pshader.getUniformLocation("gui"), 1.0);
26.         pshader.endShader();
27. ...