[p5.js 2.0 Bug Report]: Issue with Directional Lighting relative to the camera

[Gabrz]

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

2.0.0 and above (currently 2.0.5)

Web browser and version

Google Chrome 139.0.7258.155 (Official Build) (64-bit)

Operating system

Windows

Steps to reproduce this

Steps:

1. Run Example https://editor.p5js.org/Gabrz/sketches/8-h61uoAE and watch the lighted side of the cube (it moves).
2. Switch to version 1.11.0 and run the sketch again. (light source stays fixed from right side)

Snippet:

let cam;
function setup() {
  createCanvas(600, 400, WEBGL);
  cam = createCamera()
}

function draw() {
  background(30);

  // Enable orbit control
  orbitControl(2,2,2);

  // Get camera position and target
  let eye = createVector(cam.eyeX, cam.eyeY, cam.eyeZ);
  let center = createVector(cam.centerX, cam.centerY, cam.centerZ);
  let up = createVector(cam.upX, cam.upY, cam.upZ);

  // Compute camera direction
  let camDir = p5.Vector.sub(center, eye).normalize();

  // Compute left vector (cross product of up and direction)
  let camLeft = up.cross(camDir).normalize();

  // Set directional light from the left of the camera
  directionalLight(255, 255, 255, camLeft.x, camLeft.y, camLeft.z);
  ambientLight(50);

  // Draw a box
  push();
  //specularMaterial(250);
  box(100);
  pop();
}

[davepagurek]

Hi! The problem here is that in 2.0, you have to explicitly call setCamera(cam). In 1.x, creating a camera would also automatically apply it, but this lead to confusion when working with multiple cameras, especially when some are on framebuffers. In 2.0, if you add setCamera(cam) after creating the camera, it should behave the same as 1.x without that line.

[Gabrz]

Thank you! Adding setCamera solved the issue.