adding new uniforms for custom shaders

[kklibo]

@asny One of my next in-project tasks is rendering photos with lens warp compensation: to do this, I need to pass some uniforms to the fragment shader to set the distortion parameters. Right now, I'm using MeshPrograms: is there a way to feed my own uniform inputs to the shaders?

[asny]

That is a big yes. I have made sure that you can always combine the high and low level features so you are not constrained in any way. In your case it is as simple as calling the methods starting with use_uniform on MeshProgram, so if you want to send a float, use the use_uniform_float. This functionality is really part of Program but MeshProgram derefs to Program so you have the same functionality.
Note I renamed the use_uniform functionality in a recent commit to make it consistent, otherwise it is called add_uniform.

[kklibo]

Very convenient, I had it working in about 60 seconds.

[asny]

Really glad to hear 🥳