SetImageBlendMode( slot, blend_mode )
Set the blend_mode of an image
BLEND MODES
BLENDMODE_NONE - No Blending
BLENDMODE_BLEND - Alpha Blending
BLENDMODE_ADD - Additive Blending
BLENDMODE_MOD - Color Modulate
Example:
LoadImage(0, "tst.png")
SetImageBlendMode(0, BLENDMODE_BLEND)