void Scene::CreateShadowMap( FrameBuffer *shadMapBuf, float *shadMapMatrixTranspose, int lightNum, float shadowMapBias )
{
// Go ahead and render the shadow map
glPushAttrib( GL_COLOR_BUFFER_BIT );
glColorMask( GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE );
shadMapBuf->BindBuffer();
shadMapBuf->ClearBuffers();
glMatrixMode( GL_PROJECTION );
glPushMatrix();
glLoadIdentity();
LightPerspectiveMatrix( lightNum, shadMapBuf->GetAspectRatio() );
glMatrixMode( GL_MODELVIEW );
glPushMatrix();
glLoadIdentity();
LightLookAtMatrix( lightNum );
//this->Draw( MATL_FLAGS_NONE, OBJECT_OPTION_NONE, true );
this->Draw( MATL_FLAGS_NONE, OBJECT_OPTION_USE_LOWRES, true );
glPopMatrix();
glMatrixMode( GL_PROJECTION );
glPopMatrix();
glMatrixMode( GL_MODELVIEW );
shadMapBuf->UnbindBuffer();
glPopAttrib();
// Now compute the shadow map matrix for use by the current eye/camera view
glPushMatrix();
glLoadIdentity();
glTranslatef( 0.5f, 0.5f, 0.5f + shadowMapBias );
glScalef( 0.5f, 0.5f, 0.5f );
LightPerspectiveMatrix( lightNum, shadMapBuf->GetAspectRatio() );
LightLookAtMatrix( lightNum );
camera->InverseLookAtMatrix();
glGetFloatv(GL_TRANSPOSE_MODELVIEW_MATRIX, shadMapMatrixTranspose);
glGetFloatv(GL_TRANSPOSE_MODELVIEW_MATRIX, shadMapTransMatrix[lightNum]); // The scene's internal storage
glGetFloatv(GL_MODELVIEW_MATRIX, shadMapMatrix[lightNum]); // The scene's internal storage
glPopMatrix();
shadowMapTexID[lightNum] = shadMapBuf->GetDepthTextureID();
}
// This creates a shadow map. The rendering pass is already done for you, but you need to
// fill in the matrix creation code (though all the subparts are available in the framework)
void Scene::CreateShadowMap( FrameBuffer *shadMapBuf, float *shadMapMatrixTranspose, int lightNum, float shadowMapBias )
{
// Go ahead and render the shadow map
glPushAttrib( GL_COLOR_BUFFER_BIT );
glColorMask( GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE );
shadMapBuf->BindBuffer();
shadMapBuf->ClearBuffers();
// Set up the projection matrix for the shadow map
glMatrixMode( GL_PROJECTION );
glPushMatrix();
glLoadIdentity();
LightPerspectiveMatrix( lightNum, shadMapBuf->GetAspectRatio() );
// Set up the modelview ( i.e., light gluLookAt() )
glMatrixMode( GL_MODELVIEW );
glPushMatrix();
glLoadIdentity();
LightLookAtMatrix( lightNum );
this->Draw( MATL_FLAGS_NONE, OBJECT_OPTION_NONE, true );
glPopMatrix();
// Go ahead and pop off the new projection and modelview matrices
glMatrixMode( GL_PROJECTION );
glPopMatrix();
glMatrixMode( GL_MODELVIEW );
shadMapBuf->UnbindBuffer();
glPopAttrib();
// Now compute the shadow map matrix for use by the current eye/camera view
glPushMatrix();
glLoadIdentity();
// Put here the commands to create the shadow map matrix. Note: The
// Scene and Camera classes give you access to functions that multiply
// bits of the shadow map matrix onto the current matrix stack. You
// simply need to discover what they are and apply them in the right
// order here. The scale and bias matrix needs to be done yourself,
// however (and you should try to use the shadowMapBias) parameter.
glGetFloatv(GL_TRANSPOSE_MODELVIEW_MATRIX, shadMapMatrixTranspose); // Copy the transpose matrix
glGetFloatv(GL_TRANSPOSE_MODELVIEW_MATRIX, shadMapTransMatrix); // Also copy to the scene's internal storage
glPopMatrix();
// Make sure the Scene class knows where the shadow map is stored.
shadowMapTexID = shadMapBuf->GetDepthTextureID();
}
