Using Texture Maps in WebGL

Using textures in WebGL is also the same as in OpenGL, but handling the loading and setup is much simpler, since HTML lends a helping hand. In fact, loading a texture from a file is a one-line operation. In our demo, we use a single texture named OpenGL-logo.png.

var image = new Image();image.src = "OpenGL-logo.png";

Yes; that’s all there is to loading the pixels from the image into a variable. However, HTML pages load asynchronously, so knowing when the image file has been received and loaded needs to be handled in a callback. Fortunately, JavaScript has a ready-made method in the Image class for handling that situation: onload(). We can specify the onload() method as follows:

image.onload = function () {    configureTexture(image); ...

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