New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Unpack premultiplied alpha? #6

Open

deathcap opened this issue Jun 14, 2014 · 0 comments

Member

deathcap commented Jun 14, 2014

Consider enabling premultiplied alpha unpacking before loading the texture atlas into WebGL:

gl.pixelStorei(gl.UNPACK_PREMULTIPLY_ALPHA_WEBGL, true)

This has many advantages:

https://home.comcast.net/~tom_forsyth/blog.wiki.html#%5B%5BPremultiplied%20alpha%5D%5D
http://blogs.msdn.com/b/shawnhar/archive/2009/11/06/premultiplied-alpha.aspx
http://kriscg.blogspot.co.uk/2009/11/premultiplied-alpha.html
http://stackoverflow.com/questions/11521035/blending-with-html-background-in-webgl

but the blending function in voxel-shader may also have to change:

gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.blendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)
gl.blendFuncSeparate(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA, gl.ONE, gl.ONE_MINUS_SRC_ALPHA)

also see:

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment