Making a shader that can be toggled on and off

pigna

I need to draw an outline around my mesh, and the way I am doing it right now is to use a shader as the next_pass of the object's material. However, the way I am controlling if the outline is visible or not is by setting ALPHA to either 0 or 1, wich I assume is quite inefficient since it's dealing with transparency. What are the other options? Can I just enable/disable next_pass on the shader?

cybereality

You can access the shader (change the shader) or change the next pass with code. The property is called "next_pass" on the material, which you can get with "get_surface_material(0)".