Fully load all shaders to prevent future performance hiccups.
Usually graphics drivers do not actually prepare shaders until they are first needed.
However when some object is first rendered with a previously unused shader, there
can be a hiccup because the driver is compiling/optimizing the shader. This can be quite
noticeable, especially on mobile platforms.
Calling this function will perform dummy one-invisible-triangle rendering
with all variants of all currently loaded shaders. This can take some time but helps
to avoid hiccups in the future. Generally it is better to use ShaderVariantCollection for a more granular
shader warmup control.
Please be aware that this function will only warmup shaders that are currently loaded (either explicitly, or via references to Prefabs which use custom shaders).
If you use Resources.Load to load shaders, you will need to call WarmupAllShaders again.
See Also: ShaderVariantCollection for a more granular shader warmup control.