在Node.js环境下使用glTF-js-utils设置纹理是否可行？

Great question! Since glTF-js-utils is built with browser environments in mind (relying on HTMLImageElement or HTMLCanvasElement), we need a workaround to handle textures in Node.js where those DOM types don't exist. Here are two reliable approaches:

Use Node-Canvas to Mimic Browser Canvas/Image Elements #

The canvas npm package (commonly referred to as node-canvas) provides API-compatible replacements for HTMLCanvasElement and HTMLImageElement that work natively in Node.js. This is the most straightforward solution because glTF-js-utils will recognize these objects as valid TextureImageType inputs.

Step-by-Step Implementation: #

1. Install the package:

   npm install canvas
   

2. Load your texture image and create a valid Texture instance:

   const { loadImage, createCanvas } = require('canvas');
   const { Texture } = require('gltf-js-utils');
   
   // Load an image file directly
   loadImage('./assets/your-texture.png')
     .then((image) => {
       // Create a Texture using the node-canvas Image object
       const texture = new Texture(image);
       // Use the texture as needed (e.g., assign to a material)
     })
     .catch((err) => console.error('Failed to load image:', err));
   
   // If you need to modify the texture first, use a Canvas
   loadImage('./assets/your-texture.png')
     .then((image) => {
       const canvas = createCanvas(image.width, image.height);
       const ctx = canvas.getContext('2d');
       // Draw and modify the image (e.g., resize, apply filters)
       ctx.drawImage(image, 0, 0, canvas.width, canvas.height);
       
       const modifiedTexture = new Texture(canvas);
       // Proceed with your glTF operations
     });
   

Node-canvas's Image and Canvas objects mirror the structure and key properties (like width, height, and for Canvas, the getContext method) that glTF-js-utils expects, so they work seamlessly with the library's Texture class.

Alternative: Manually Supply Pixel Data (Advanced) #

If you prefer not to use node-canvas, you could use an image processing library like sharp to extract raw pixel data, then create a minimal object that matches the shape of TextureImageType. However, this requires more work since you'd need to replicate the properties glTF-js-utils uses to process the texture.

For example, with sharp:

const sharp = require('sharp');
const { Texture } = require('gltf-js-utils');

sharp('./assets/your-texture.png')
  .raw()
  .toBuffer({ resolveWithObject: true })
  .then(({ data, info }) => {
    // Create a mock object with required properties
    const mockImage = {
      width: info.width,
      height: info.height,
      // You may need to add more properties depending on glTF-js-utils's internal usage
      // This approach is less reliable than node-canvas, as it depends on the library's unpublicized logic
    };
    // Note: This might not work out of the box, since glTF-js-utils may expect a way to access pixel data
    // Node-canvas is still the better choice here
  });

This advanced approach is not recommended unless you have specific constraints, as it relies on reverse-engineering how glTF-js-utils interacts with the image/canvas objects.

内容的提问来源于stack exchange，提问作者SiarheiK