different behavior of focus mask True between GL/DX

[jack_norton]

I found this bug, is quite simple:
- if you use OpenGL the focus mask works correctly
- if you use DirectX/Angle, the focus mask is ignored and even the transparent part of the image get focus

the code I'm using is just standard imagebutton:
    if isinparty(rei):
        $img=im.FactorScale("gfx/camp/rei.png",0.86)
        imagebutton idle im.MatrixColor(img,im.matrix.brightness(-0.2)) hover (img) action Jump("talk_rei") yanchor 1.0 ypos 1.00 xcenter 0.73 focus_mask True
    if isinparty(karen):
        $img=im.FactorScale("gfx/camp/karen.png",0.86)
        imagebutton idle im.MatrixColor(img,im.matrix.brightness(-0.2)) hover (img) action Jump("talk_karen") yanchor 1.0 ypos 1.0 xcenter 0.58 focus_mask True
    if isinparty(amukiki):
        $img=im.Flip(im.FactorScale("gfx/camp/amukiki.png",0.94), horizontal=True)
        imagebutton idle im.MatrixColor(img,im.matrix.brightness(-0.2)) hover (img) action Jump("talk_amukiki") yanchor 1.0 ypos 1.05 xcenter 0.34 focus_mask True

[Tom Rothamel (renpytom)]

This will be fixed in 6.13.9.