Fall back to canvas when WebGL is not supported about deprecated-glsl.js HOT 2 CLOSED

Are you referring to games like the snake example? When you have one canvas 2d for drawing and a canvas webgl for post-processing?

If so, it is not fixable in the library itself, glsl.js is a tiny toolkit on top of GLSL, using a canvas2d with it is already a specific use-case.

But you can easily solve that in different ways, here is one:
put the 2 canvas one on top of the other :)

canvas#2d {
  position: absolute;
  top: 0;
  bottom: 0;
  z-index: 1;
}
canvas#webgl {
  position: absolute;
  top: 0;
  bottom: 0;
  z-index: 2;
}

Then check for support:

// ... do your canvas #2d work
if (Glsl.supported()) {
  // Do your Glsl({ .. }) with the canvas #webgl
}

A canvas is transparent by default, so it should make the 2d canvas visible if you don't use it.

from deprecated-glsl.js.

I did indeed base this issue on the snakes example :)

I just figured that the library always took a canvas as input for the shaders but your response makes perfect sense when the input can be from any source(s).

Thanks for your reply and (another) great library :)

from deprecated-glsl.js.