Introduce Depth Access for Filters Functionality

Increasing access

The feature request entails an enhancement to the current functionality of the filters() function. It proposes the addition of a third parameter, allowing for depth access when applying filters.

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

This parameter would be utilized in the following format: filter(BLUR, BLUR-VALUE, DEPTH). Previously, our implementation relied on p5.Graphics, which facilitated filter access through a hidden WEBGL canvas. Now, with the transition to framebuffers, which serve a similar purpose, we have the opportunity to incorporate depth into filter shaders. Initially, this update will focus on integrating depth into filters applied through framebuffers. Subsequently, we plan to extend this capability to encompass 2D filters as well, ensuring a comprehensive enhancement to our filtering system. Maybe giving depth access to 2D filters can be a follow-up update.

Following the implementation of depth buffers for filters, we can expand the range of available filters that utilize depth, such as adding a Fog filter. The addition of depth is crucial for the Fog filter, as it enables objects closer to the viewer to be less obscured by fog, while objects farther away appear more obscured.

An image I found from photoshop:- Maybe a depth blur filter will look something like-

Maybe a depth fog filter will look something like:-(maybe fog can be a followup update after adding depth access to filters)

Start by tracing the WebGL filters() function and the framebuffer path mentioned in the request, then inspect how filter(BLUR, BLUR-VALUE) currently handles its inputs. Define the framebuffer depth-access behavior first; the initial work is done when filters applied through framebuffers can use depth, with 2D filter support and depth-based filters treated as follow-ups.