LWJGL Forum

Programming => OpenGL => Topic started by: DanDanger on March 17, 2006, 23:34:19

Title: Reaaly slow vertex + fragment shader
Post by: DanDanger on March 17, 2006, 23:34:19
Hello,

Ive written a vertex and fragment shader (the simplest you can imagine) however when i try to render anything with these activated it renders INCREDIBELY slowly. Has anyone had any problems like this? Im using an ATI x800 gfx card and the logs claim that the vertex+frag shaders are running in hardware.

This has been driving me nuts for about 3 days now so any help would be really appreciated ^_^

// vert shader
void main()
{
   gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
}

// frag shader
void main()
{
  gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
}

-------- additional info --------
Having disabled the fragment shader it now runs at full speed.
Title: Reaaly slow vertex + fragment shader
Post by: spasi on March 18, 2006, 12:43:16
There are some GL states that, if enabled, cause software rendering when using GLSL fragment shaders on ATI cards. I've found the following to be problematic in many occasions:

QuoteAA lines, AA points, wide lines, wide points, line stipple, polygon stipple and polygon offset.

Try disabling some of the above (if enabled) and see what happens.
Title: Reaaly slow vertex + fragment shader
Post by: DanDanger on March 18, 2006, 13:04:29
You sir, are a genius! I love you and want to have your children ^_^

by putting in this:

GL11.glDisable(GL11.GL_LINE_SMOOTH);

my fragment shader runs at full speed! I can get on with the rest of me game now!

Thank you so very much ^_^




Quote from: "spasi"There are some GL states that, if enabled, cause software rendering when using GLSL fragment shaders on ATI cards. I've found the following to be problematic in many occasions:

QuoteAA lines, AA points, wide lines, wide points, line stipple, polygon stipple and polygon offset.

Try disabling some of the above (if enabled) and see what happens.