画布渐变

Question

I'm trying to create a color selector shaped like a triangle. I'm looking at things like color wheel( http://jweir.github.com/colorwheel/ ) but I don't know how to modify it so that I can change the shape of the square to a triangle

Answer 1

the simplest method would be to have an image with all your colors pre-drawn. cope the image to a canvas and use canvasPixelArray to get the color and alpha if desired.