Horrible Canvas GetImageData() / PutImageData() performance on mobile?

Phrogz has the right idea. You really just want to paint a half-transparent (or ratio-transparent) black over the whole thing with 'source-atop' globalCompositeOperation.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.