Add Gradients for Fill and Strokes

Increasing access

This would make many more things possible in p5.js without incurring the heavy performance cost of writing to a texture manually from the CPU or drawing a gradient using strokes, and without requiring the burden of shifting to WebGL and using shaders to achieve the gradient effect.

Most appropriate sub-area of p5.js?

• Accessibility
• Color
• Core/Environment/Rendering
• Data
• DOM
• Events
• Image
• IO
• Math
• Typography
• Utilities
• WebGL
• Build process
• Unit testing
• Internationalization
• Friendly errors
• Other (specify if possible)

Feature request details

Add the ability to use gradients instead of pure colors as a default option using canvas gradients for P2D/HTMLCanvas and WebGL vertex color interpolation for WebGL mode.

Start by examining the P2D/HTMLCanvas and WebGL rendering paths described in the request, along with how fill and stroke colors are currently handled. Define the API and behavior for gradients in both modes, then verify that gradients work for fills and strokes without requiring manual textures or custom shaders.