I noticed that if you set ALPHA_PREMULTIPLIED for a sprite, then the opacity doesn't work. With ALPHA_NON_PREMULTIPLIED it works well. But ALPHA_NON_PREMULTIPLIED doesn't suit me, because the sprite becomes black, if you reduce the value of opacity.
What BlendFunc should I use for the sprite to be without black border and for opacity to work well?
Thanks for any idea!