Method drawScene

samples/_opengl/StencilReflection/src/StencilReflectionApp.cpp:75–122

}

void StencilReflectionApp::drawScene()
{
	gl::clear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
	gl::ScopedMatrices scopeMatrices;
	{
		gl::setMatrices( mCam );
		gl::multModelMatrix( translate( vec3( 0, -2, -1.5 ) ) );
		gl::multModelMatrix( rotate( -mRotation, vec3( 0, 0, 1 ) ) );
		{
			// enable stencil test to be able to give the stencil buffers values.
			gl::ScopedState scopeStencil( GL_STENCIL_TEST, true );
			gl::stencilFunc( GL_ALWAYS, 1, 0xFF );
			gl::stencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
			gl::stencilMask( 0xFF );
			gl::depthMask( GL_FALSE );
			gl::clear( GL_STENCIL_BUFFER_BIT );
			// draw the seperation plane into the stencil buffer.
			{
				gl::ScopedModelMatrix	scopeModel;
				gl::multModelMatrix( translate( vec3( 0, 0, 1.5 ) ) );
				gl::color( ColorA( 0, 0, 0, 1 ) );
				gl::drawSolidRect( Rectf( -1.25, -1.25, 1.25, 1.25 ) );
			}
			// now tell the stencil what type of stenciling it has.
			gl::stencilFunc( GL_EQUAL, 1, 0xFF );
			gl::stencilMask( 0x00 );
			gl::depthMask( GL_TRUE );
			// draw into that stenciled area
			{
				gl::ScopedModelMatrix	scopeModel;
				gl::ScopedBlendAlpha	scopeAlphaBlend;
				gl::ScopedState			scopeCull( GL_CULL_FACE, true );
				gl::multModelMatrix( translate( vec3( 0, 0, 1 ) ) );
				gl::color( ColorA( 1.0f, 1.0f, 1.0f, .09f ) );
				
				glCullFace( GL_FRONT );
				gl::drawCube( vec3( 0, 0, 1), vec3( 1, 1, 1 ) );
				
				glCullFace( GL_BACK );
				gl::drawCube( vec3( 0, 0, 1), vec3( 1, 1, 1 ) );
			}
		}
		// This scope closes so Stencil test will no longer be performed
		// The below colorCube's rendering will be unaffected.
		gl::color( ColorA( 1, 1, 1, 1 ) );
		gl::drawColorCube( vec3( 0, 0, 1), vec3( 1, 1, 1 ) );
	}
}

// Enabling stencil on the system framebuffer
auto options = RendererGl::Options().msaa( 16 ).stencil();