Enabling and Disabling Effects

Since the EffectPass bakes effects into a single shader, enabling or disabling one effect at runtime would require a slow recompilation of the shader program. The EffectPass actually provides a recompile method that allows you to do that, but it blocks the render thread and causes a noticeable hiccup when performed at runtime. This method is not intended for toggling effects and should only be used in a situation where a user changes special effect parameters that require a shader recompilation.

Instead, you should prepare multiple EffectPass instances with the desired Effect combinations ahead of time and enable or disable these passes as needed using the Pass.enabled flag. This requires some planning ahead and uses a little bit more memory but is the most efficient solution. Note that Effect instances can be reused in other EffectPass instances so you won't have to worry about redundant frame buffers.