Limit Scope of Default Uniforms

How would this new feature help increase access to p5.js?

Makes writing custom shaders more transparent.
Currently there are a couple of uniform names that are used by the default shaders. If a user uses these names in their program, the uniform values they set will get overwritten with the default values (and their program won't behave as they expect it to).

Most appropriate sub-area of p5.js?

• WebGL

Feature enhancement details:

The default shaders declare and use some uniforms. These reserved names are not known to a user. Rather than telling the user not to use this seemingly arbitrary list of reserved names, a better solution is to just not set these default uniforms when a user-defined shader is used (via shader()).

More discussion on this can be found on the related issue on the p5.js-website repo.

Start by reviewing the default shaders in src/webgl/shaders and the shader() reference to understand how default uniforms are applied. Check the related p5.js-website issue for discussion context. Done means user-defined shader uniforms with matching names are no longer overwritten, while default shaders retain their required uniform values.