PixiPlugin: Error with animating fillColor with PixiJS v8

[matt-bp]

Problem

In PixiJS V8, I get an error when trying to animate the fill color of a PIXI.Graphics using the PixiPlugin.

Example

https://codepen.io/matt-bp/pen/XWQYgVK

Uncomment the second gsap.to to see the error.

My workaround (also for anyone else experiencing this issue)

I'm currently working around this error by creating a color object with three properties (r, g, b), using gsap to animate each color channel individually. I'm then using the onUpdate property in the gsap.to options to update the graphic's fill color and call graphics.fill() to update the color.

// ... Other pixijs setup

const color = {r: 0, g: 0, b: 255};
const target = {r: 100, g: 10, b: 255};

const graphics = new PIXI.Graphics();
graphics.rect(0, 0, 100, 100);
graphics.fillStyle.color = rgbToHex(color.r, color.g, color.b);
graphics.fill();
app.stage.addChild(graphics);

const updateFill = () => {
  color.r = Math.floor(color.r);
  color.g = Math.floor(color.g);
  color.b = Math.floor(color.b);

  graphics.fillStyle.color = rgbToHex(color.r, color.g, color.b);
  graphics.fill();
};

gsap.to(color, {r: target.r, g: target.g, b: target.b, duration: 2, onUpdate: updateFill, yoyo: true, repeat: -1});