Sprite Transparency

I'm making my own WAD, and I want to reskin the cyberdemon to a certain image. I don't need different animations for the sprite, just the static image. I have no problem replacing the sprites, but there is an issue. A black box appears around the sprite, even though it shoudn't. Is there any way to fix this?

Use "Renderstyle Add" in the actor's DECORATE properties.

No, fix the sprite. RenderStyle Add will render your cyberdemon with additive translucency, so yes the black will disappear, but the sprite itself will seem to be glowing.

Hm, good point. I'm more interested in the reason why the sprite is filled with black instead of being transparent in the 1st place. I've seen many effect sprites do that and I never got why. Will there be a difference if both sprites have Renderstyle Add but one is transparent and the other has a solid black background?

Lud said:

Hm, good point. I'm more interested in the reason why the sprite is filled with black instead of being transparent in the 1st place. I've seen many effect sprites do that and I never got why. Will there be a difference if both sprites have Renderstyle Add but one is transparent and the other has a solid black background?

There'll be a difference in the automap if you use the automap cheat to see things (iddt twice) and the option to see things as sprites instead of little triangles. Automap sprites ignore their render style.

Otherwise, nope, no visual difference. True black is zero on all color channels, so adding zero to the background color will not change it.

Now, if it's not really black but just a very dark gray (e.g. #020202) then there will be a slight difference.

Gez said:

Otherwise, nope, no visual difference. True black is zero on all color channels, so adding zero to the background color will not change it.

That is not correct. While with normal colors, black is nothing when rendered additively, this is not true if the invulnerability effect is on, making lots off effect mods that were too lazy to set proper translucency look really bad.

LegendaryLegate said:

I'm making my own WAD, and I want to reskin the cyberdemon to a certain image. I don't need different animations for the sprite, just the static image. I have no problem replacing the sprites, but there is an issue. A black box appears around the sprite, even though it shoudn't. Is there any way to fix this?

You should post the PNG sprite(s) you're talking about. Maybe put them in a zip file.

If you're using Slade, when converting the image, set black as the transparent color.

Graf Zahl said:

That is not correct. While with normal colors, black is nothing when rendered additively, this is not true if the invulnerability effect is on, making lots off effect mods that were too lazy to set proper translucency look really bad.

Forgot about invuln. Yeah, there's that too; and possibly other color-affecting effects like potentially some translations.