   texture blend after dependent texture?
  hi,i'm wondering if it's possible to do a texture blend on the results of a dependent texture lookup? (ie: TEXTURE0 and TEXTURE1 are dependent textures; i want to blend that result with TEXTURE2). i've got the dependent texture lookup working but the blend doesn't do anything (not sure if i setup the blending for TEXTURE2 correctly but at least no GL errors reported):    glEnable( GL_TEXTURE_SHADER_NV );    // texture 0 - 3D texture lookup    glActiveTexture( GL_TEXTURE0 );    glBindTexture( GL_TEXTURE_3D, m_nLabelTextureID );    glTexEnvi( GL_TEXTURE_SHADER_NV, GL_SHADER_OPERATION_NV, GL_TEXTURE_3D );    // texture 1 - dependent texture    glActiveTexture( GL_TEXTURE1 );    glBindTexture( GL_TEXTURE_2D, m_nMaskTextureID );    // alpha/red = tex coords into texture 1    glTexEnvi( GL_TEXTURE_SHADER_NV, GL_SHADER_OPERATION_NV, GL_DEPENDENT_AR_TEXTURE_2D_NV );    glTexEnvi( GL_TEXTURE_SHADER_NV, GL_PREVIOUS_TEXTURE_INPUT_NV, GL_TEXTURE0_ARB );    glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE );    // blend with luminance texture    glActiveTexture( GL_TEXTURE2 );    glTexEnvi( GL_TEXTURE_SHADER_NV, GL_SHADER_OPERATION_NV, GL_NONE );    glEnable( GL_TEXTURE_3D );    glDisable( GL_TEXTURE_2D );    glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE );    glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB, GL_MODULATE );    glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_ALPHA, GL_MODULATE );    glTexEnvi( GL_TEXTURE_ENV,GL_SOURCE0_RGB,GL_PREVIOUS );glTexEnvi( GL_TEXTURE_ENV,GL_SOURCE1_RGB,GL_TEXTURE2 );    glTexEnvi( GL_TEXTURE_ENV,GL_SOURCE0_ALPHA,GL_PREVIOUS ); // tell GL the data for Arg0 comes from the previous texture    glTexEnvi( GL_TEXTURE_ENV,GL_SOURCE1_ALPHA,GL_TEXTURE2 );    glTexEnvi( GL_TEXTURE_ENV,GL_OPERAND0_RGB,GL_SRC_COLOR );    glTexEnvi( GL_TEXTURE_ENV,GL_OPERAND1_RGB,GL_SRC_COLOR );glTexEnvi( GL_TEXTURE_ENV,GL_OPERAND0_ALPHA,GL_SRC_ALPHA );    glTexEnvi( GL_TEXTURE_ENV,GL_OPERAND1_ALPHA,GL_SRC_ALPHA ); Render function looks something like:glMultiTexCoord3f( GL_TEXTURE0, (*iter).vTextureCoords.x, (*iter).vTextureCoords.y, (*iter).vTextureCoords.z );glMultiTexCoord3f( GL_TEXTURE2, (*iter).vTextureCoords.x, (*iter).vTextureCoords.y, (*iter).vTextureCoords.z );   glVertex3f( (*iter).vPos.x, (*iter).vPos.y, (*iter).vPos.z );Thanks for any tips.   