Sure, I’m setting ofEnableAlphaBlending(); in the Draw-routine.
And everything is fine if I load a PNG-image.
But a JPEG (exported from Phostoshop) shows no transparency.
If I check img.bpp (after setting the image type to OF_IMAGE_COLOR_ALPHA) it says 32, so there should be an alpha-channel.
jpeg doesn’t support alpha channel i think, so when you set the type to COLOR_ALPHA, it converts the image to 32 bits and adds an alpha channel but there’s no information to generate the alpha so all of it is set to 255.
You are right, it looks like setImageType(OF_IMAGE_COLOR_ALPHA) should work, maybe it’s a bug. On a side note, this isn’t the same obviously, but if you want to draw the jpg transparently you can just do: