KhronosGroup/glTF — pull request #319 by tfili (2014-08-07 15:17:36+00:00)
Title: Fixes issue that a 4 channel png automatically causes a transparent mesh

This was causing problems because opaque meshes were getting rendered transparent just because their png was 4 channels. We now check the alpha channels till we find a non-opaque pixel before we mark it as transparent.