I know how to add per-materal parameter. How to add the global one?
I am going to just add new cbuffer and set uniform through Graphics.
How to add new global shader parameter?
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You can’t be sure that cbuffers will be used (D3D9, OpenGL ES, or even OpenGL 3 when cbuffer use is intentionally disabled)
Currently view-global shader parameters are hardcoded to be set in the View class.
Maybe you should add a new event to the engine that is sent during View::SetGlobalShaderParameters(), which would allow code outside the engine to set shader parameters. The issue here is that you need to be able to re-assign the global parameter whenever new shaders are set into use, as (without cbuffers) the uniform/register index can change.
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Since I needed to add another new event too, there’s now an event E_VIEWGLOBALSHADERPARAMETERS in the master branch that’s sent when the global parameters are set. Additional parameters can be set at this point.