Can I bind a float GL_TEXTURE_RECTANGLE_NV texture to a fragment program using
cgGLSetTextureParameter( paraFpTexture, fptexture ) ?

I used following code to test it, but the result it all black. Any idea?

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cgGLBindProgram(vProgram);
cgGLEnableProfile(vProfile);

cgGLBindProgram(fProgram);
cgGLEnableProfile(fProfile);

cgGLSetStateMatrixParameter( paraVpModelViewProj,
CG_GL_MODELVIEW_PROJECTION_MATRIX, CG_GL_MATRIX_IDENTITY ) ;

cgGLSetTextureParameter( paraFpTexture, fptexture ) ;
cgGLEnableTextureParameter( paraFpTexture ) ;

glTranslatef(-0.5, -0.5,-0.9);
glBegin(GL_QUADS);
glTexCoord2f(0.0, 0.0); glVertex2f(0.0, 0.0);
glTexCoord2f(width, 0.0); glVertex2f(1.0, 0.0);
glTexCoord2f(width, height); glVertex2f(1.0, 1.0);
glTexCoord2f(0.0, height); glVertex2f(0.0, 1.0);
glEnd();

cgGLDisableTextureParameter( paraFpTexture ) ;
cgGLDisableProfile(vProfile);
cgGLDisableProfile(fProfile);
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