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Recluse
11-04-2013, 12:17 AM
Hello I have been learning the basics of GLSL and have come across a problem.

I have tried a few different variations of code and the only time I have got it to work is if I disable the tessellation.


When I run this code nothing renders....


//SOURCE CODE FOR VERTEX SHADER

static const GLchar* vertShaderSource[] =
{
"#version 430 core \n"
"layout (location = 0) in vec4 offset; \n"
"layout (location = 1) in vec4 color; \n"
"out vec4 vs_color; \n"
"void main(void) \n"
"{ \n"
"const vec4 vertices[3] = vec4[3](vec4(0.25,-0.25,0.5,1.0),vec4(-0.25,-0.25,0.5,1.0),vec4(0.25,0.25,0.5,1.0)); \n"
"gl_Position = vertices[gl_VertexID] + offset; \n"
"vs_color=color; \n"
"} \n"
};

//SOURCE FOR TESSALATION CONTROL SHADER
static const GLchar* TCSsource[] =
{
"#version 430 core \n"
"layout (vertices = 3) out; \n"
"void main(void) \n"
"{ \n"
"if(gl_InvocationID == 0) \n"
"{ \n"
"gl_TessLevelInner[0] = 5.0; \n"
"gl_TessLevelOuter[0] = 5.0; \n"
"gl_TessLevelOuter[1] = 5.0; \n"
"gl_TessLevelOuter[2] = 5.0; \n"
"} \n"
"gl_out[gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position; \n"
"} \n"
};


//SOURCE FOR THE TEESALATION CONTROL SHADER
static const GLchar* TEShaderSource[] =
{
"#version 430 core \n"
"layout (triangles,equal_spacing,cw) in; \n"
"in vec4 vs_color; /n"
"out vec4 tes_color; \n"
"gl_Position = (gl_TessCoord.x * gl_in[0].gl_Position + gl_TessCoord.y * gl_in[1].gl_Position + gl_TessCoord.z * gl_in[2].gl_Position); \n"
"tes_color = vs_color; \n"
"} \n"
};


//SOURCE CODE FOR FRAGMENT SHADER
static const GLchar* fragShaderSource[] =
{
"#version 430 core \n"
" \n"
"in vec4 tes_color;"
"out vec4 color; \n"
" \n"
"void main(void) \n"
"{ \n"
"color = tes_color; \n"
"} \n"
};

Recluse
11-05-2013, 03:42 AM
Here is my updated code... but it still doesn't work.


static const GLchar* vertShaderSource[] =
{
"#version 430 core \n"
"layout (location = 0) in vec4 offset; \n"
"layout (location = 1) in vec4 color; \n"
"out vec4 vs_color; \n"
"void main(void) \n"
"{ \n"
"const vec4 vertices[3] = vec4[3](vec4(0.25,-0.25,0.5,1.0),vec4(-0.25,-0.25,0.5,1.0),vec4(0.25,0.25,0.5,1.0)); \n"
"gl_Position = vertices[gl_VertexID] + offset; \n"
"vs_color[gl_VertexID]=color; \n"
"} \n"
};

//SOURCE FOR TESSALATION CONTROL SHADER
static const GLchar* TCSsource[] =
{
"#version 430 core \n"
"layout (vertices = 3) out; \n"
"in vec4 vs_color[]; \n"
"out Tess{ \n"
"vec4 tcs_color; \n"
"} Out[]; \n"
"void main(void) \n"
"{ \n"
"if(gl_InvocationID == 0) \n"
"{ \n"
"gl_TessLevelInner[0] = 5.0; \n"
"gl_TessLevelOuter[0] = 5.0; \n"
"gl_TessLevelOuter[1] = 5.0; \n"
"gl_TessLevelOuter[2] = 5.0; \n"
"} \n"
"gl_out[gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position; \n"
"Out[gl_InvocationID].tcs_color = vs_color[gl_InvocationID]; \n"
"} \n"
};


//SOURCE FOR THE TEESALATION CONTROL SHADER
static const GLchar* TEShaderSource[] =
{
"#version 430 core \n"
"layout (triangles,equal_spacing,cw) in; \n"
"in Tess{ \n"
"vec4 tcs_color; \n"
"} In[];"
"out vec4 tes_color; \n"
"void main(void) \n"
"{ \n"
"gl_Position = (gl_TessCoord.x * gl_in[0].gl_Position + gl_TessCoord.y * gl_in[1].gl_Position + gl_TessCoord.z * gl_in[2].gl_Position); \n"
"tes_color = In[0].tcs_color; \n"
"} \n"
};


//SOURCE CODE FOR FRAGMENT SHADER
static const GLchar* fragShaderSource[] =
{
"#version 430 core \n"
" \n"
"in vec4 tes_color; \n"
"out vec4 color; \n"
" \n"
"void main(void) \n"
"{ \n"
"color = tes_color; \n"
"} \n"
};