Skip to content

[p5.js 2.0 Beta Bug Report]: vertexProperty() breaks if drawing with strokes #7519

@davepagurek

Description

@davepagurek
Contributor

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)

p5.js version

2.0 beta 1

Web browser and version

Firefox

Operating system

MacOS

Steps to reproduce this

When drawing strokes, we don't duplicate custom vertex properties to the different parts of strokes. When you try to draw strokes with per-vertex properties and use a shader that reads it, you get this warning in the browser console (not the p5 editor console though! open the browser one):

WebGL warning: drawArraysInstanced: Vertex fetch requires 51780, but attribs only supply 11526.
let snake
let snakeShader

function setup() {
  createCanvas(400, 400, WEBGL);
  
  snakeShader = baseMaterialShader().modify({
    vertexDeclarations: 'in float len;'
  })
  
  const pts = []
  for (let i = 0; i < 50; i++) {
      pts.push(createVector(random(width), random(height)))
  }
  
 snake = buildGeometry(() => {
    noFill()
    beginShape()
    for (const [i, { x, y }] of pts.entries()) {
        vertexProperty('len', [i/(pts.length-1)])
        splineVertex(x, y)
    }
    endShape()
  })
}

function draw() {
  clear()
  strokeShader(snakeShader)
  model(snake)
}

Live: https://editor.p5js.org/davepagurek/sketches/KwUdPojKW

Activity

ImRAJAS-SAMSE

ImRAJAS-SAMSE commented on Feb 28, 2025

@ImRAJAS-SAMSE
Contributor

Hi @davepagurek,

I'd like to work on this issue. Based on your feedback, I plan to duplicate user-defined vertex properties similarly to how per-vertex stroke colours are handled in p5.Geometry.js.

Would you be open to me working on this?

Thanks!

davepagurek

davepagurek commented on Mar 2, 2025

@davepagurek
ContributorAuthor

Thanks @ImRAJAS-SAMSE! I'll assign this to you.

linked a pull request that will close this issue on Mar 29, 2025
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Metadata

Metadata

Assignees

Type

No type

Projects

No projects

Milestone

No milestone

Relationships

None yet

    Participants

    @davepagurek@ImRAJAS-SAMSE

    Issue actions

      [p5.js 2.0 Beta Bug Report]: vertexProperty() breaks if drawing with strokes · Issue #7519 · processing/p5.js