anima-libera / ipsys Goto Github PK

The use of

glEnable(GL_BLEND);
glBlendEquation(GL_FUNC_REVERSE_SUBTRACT);
glBlendFunc(GL_ONE, GL_ONE);
glUseProgram(g_shprog_draw_fade);
glDrawArrays(GL_POINTS, 0, 1);

doesn't seem to produce the expected result on systems using mesa drivers. Instead the framebuffer is not affected and not fading is applied.

It could be the fact that OpenGL features are misused here (but somehow still produce the expected fading with non-mesa drivers) or something else..