protected override void Draw()
{
// Render 3D targets.
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glDepthFunc(GL_LEQUAL);
activeLoop.DrawTargets();
mainTarget.Apply();
activeLoop.Draw();
// Render 2D targets.
glDisable(GL_DEPTH_TEST);
glDisable(GL_CULL_FACE);
glDepthFunc(GL_NEVER);
canvas.DrawTargets(sb);
// Draw to the main screen.
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glViewport(0, 0, (uint)Resolution.WindowWidth, (uint)Resolution.WindowHeight);
sb.ApplyTarget(null);
mainSprite.Draw(sb);
canvas.Draw(sb);
sb.Flush();
}