[p5.js 2.0 Beta Bug Report]: vertexProperty() breaks if drawing with strokes
Open
@ImRAJAS-SAMSE is already working on this.
Since Mar 2, 2025.
Area:WebGL
p5.js 2.0+
- Dominant language
- JavaScript
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Description
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
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