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question about cg shader

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Hi, i have a very simple lighting shader that works just fine. I decided to do a simple texture lookup but when i compile the shader i get a 'tex2D is not supported by current profile' message. I tried to compile the shader using all of the possible profiles (even if arbfp1 should support tex2D), so i don't understand what's wrong. If you like you can try to compile yourself, here is the shader:
struct vertex
    float4 position : POSITION;
    float4 normal   : NORMAL;
    float4 color0   : COLOR0;
    float2 texcoord0 : TEXCOORD0;

struct fragment
    float4 position : POSITION;
    float4 color0   : COLOR0;
    float2 texcoord0 : TEXCOORD0;

fragment main( vertex IN, 
               uniform float4x4 modelViewProjection,
               uniform float4x4 modelViewInverse,
		uniform float4 eyePosition,
               uniform float4 lightVector,
	       uniform sampler2D testTexture: TEXUNIT0
    fragment OUT;

    OUT.position = mul( modelViewProjection, IN.position );

    // Transform normal from model-space to view-space
    float4 normal = normalize( mul( modelViewInverse, IN.normal ).xyzz );

    // Store normalized light vector
    float4 light = normalize( lightVector );

    // Calculate half angle vector
    float4 eye = eyePosition;
    float4 half = normalize( light + eye );
    // Calculate diffuse component
    float diffuse = dot( normal, light );

    // Calculate specular component
    float specular = dot( normal, half );
    specular = pow( specular, 32 );

    // A little ambient color
    float4 ambientColor = float4(0,0,0, 1.0 );

    // White specular
    float4 specularMaterial = float4( .9,.9,.9, 1.0 );

    // Combine diffuse and specular contributions and output final vertex color
    OUT.color0 = tex2D(testTexture, IN.texcoord0 );
    //OUT.color0 = diffuse * IN.color0 + specular * specularMaterial + ambientColor ;

    return OUT;

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Sure, this is the shader initialization code:

void initShader_cg(void)
if( cgGLIsProfileSupported(CG_PROFILE_ARBFP1) )
g_CGprofile_pixel = CG_PROFILE_ARBFP1;
else if( cgGLIsProfileSupported(CG_PROFILE_FP30) )
g_CGprofile_pixel = CG_PROFILE_FP30;
else if( cgGLIsProfileSupported(CG_PROFILE_FP20) )
g_CGprofile_pixel = CG_PROFILE_FP20;
MessageBox( NULL,"Failed to initialize pixel shader! Hardware doesn't "
"support any of the pixel shading extensions!",

if( cgGLIsProfileSupported(CG_PROFILE_ARBVP1) )
g_CGprofile2 = CG_PROFILE_ARBVP1;
else if( cgGLIsProfileSupported(CG_PROFILE_VP30) )
g_CGprofile2 = CG_PROFILE_VP30;
else if( cgGLIsProfileSupported(CG_PROFILE_VP20) )
g_CGprofile2 = CG_PROFILE_VP20;
MessageBox( NULL,"Failed to initialize vertex shader! Hardware doesn't "
"support any of the vertex shading extensions!",

// Create the context...
g_CGcontext2 = cgCreateContext();

// Create the vertex shader...

g_CGprogram2 = cgCreateProgramFromFile( g_CGcontext2,

// Load the program using Cg's expanded interface...

cgGLLoadProgram( g_CGprogram2 );

// Bind some parameters by name so we can set them later...

g_CGparam_modelViewProj2 = cgGetNamedParameter( g_CGprogram2, "modelViewProjection" );
g_CGparam_modelViewInverse2 = cgGetNamedParameter( g_CGprogram2, "modelViewInverse" );
g_CGparam_eyePosition2 = cgGetNamedParameter( g_CGprogram2, "eyePosition" );
g_CGparam_lightVector2 = cgGetNamedParameter( g_CGprogram2, "lightVector");

In the display function, i have the following code:

// This matrix will be used to tansform the vertices from model-space to clip-space
cgGLSetStateMatrixParameter( g_CGparam_modelViewProj2,

// This matrix will be used to transform the normals from model-space to view-space
cgGLSetStateMatrixParameter( g_CGparam_modelViewInverse2,

fLightVector[0] = 0;
fLightVector[1] = 1270*cos(camerax_pov*M_PI/180.0f);
fLightVector[2] = 560;

// Normalize light vector
float fLength = sqrtf( fLightVector[0]*fLightVector[0] +
fLightVector[1]*fLightVector[1] +
fLightVector[2]*fLightVector[2] );
fLightVector[0] /= fLength;
fLightVector[1] /= fLength;
fLightVector[2] /= fLength;

cgGLSetParameter4fv( g_CGparam_eyePosition2, fEyePosition );
cgGLSetParameter4fv( g_CGparam_lightVector2, fLightVector );
cgGLBindProgram( g_CGprogram2 );
cgGLEnableProfile( g_CGprofile2 );


cgGLDisableProfile( g_CGprofile2 );

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I think i'm doing something wrong specifying texture coordinates.
I think the error should be at the following line:

OUT.color0 = tex2D(testTexture, IN.texcoord0 );

I'm not certain if texcoord0 is properly initialized and contains texture coordinates ...

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I think the problem is that you are inserting fragment operations in a vertex program.

From you input (struct vertex) i can say this is a vp because you are using the NORMAL semantic. And your code snippet confirms that. g_CGprofile2 is a vp profile.

Doing a tex2D inside a vp is only possible in VP40 profile. If your card support vertex texture fetch (VTF) trying compiling your shader with VP40 profile. But i don't think that this is a good solution. Textures in vertex programs have no filtering applied. So i suggest you move the tex2D to a fragment program and use that with the vp you have.


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