avalanche123/Imagine — pull request #310 by romainneutron (2014-04-09 14:56:15+00:00)
Title: Fix #158: GD alpha detection + Color::isOpaque are broken

This fix #158

Alpha value equals to 100 is an opaque color, see http://en.wikipedia.org/wiki/Alpha_compositing or http://en.wikipedia.org/wiki/RGBA_color_space