Similar to this old thread, http://www.html5gamedevs.com/topic/40190-phaser-3-texture-getpixels-plural/, is there an easy way to getPixels from a loaded texture?
Thanks Samme, it does indeed work fine with WEBGL.
I found my mistake. I was trying to use the texture output from a Shader, which is a WebGLTexture, and draw that to the canvas. As it turns out, it wasnt even the texture I wanted to use.