Compileable version of Alien Breed 3D II - The Killing Grounds

[Karlos]

Originally Posted by Dunny

I think you're probably right tbh. Hey, would a true-colour RTG version be on the cards at some point? That might be a fun thing for PiStorm owners to experience.

Yes, it's on my hitlist since RTG was introduced. Some if it should be quite easy. For example, the game relies on taking a palette colour and looking up the brightness variation of that colour in a big shade table that currently maps the brightness variation of the colour to the nearest palette entry. That can just be replaced with a true colour lookup table containing the actual true colour variation of the brightness and written straight to the buffer.

That works for walls, floors and basic bitmap sprites. The only real challenge is transparency. Basic glare and shadow transparency works really well in 8-bit because all you have to do is to read the current frame pixel (which is a palette value) and look up the required shade variation again in the same big table. That isn't going to work in RGB mode. You have to do it properly. Read the RGB value from the framebuffer and adjust it accordingly. The other form of transparency is additive (plasma bolts and explosions). That may or may not be easier - it's not totally obvious how it works currently but as it only seems to work if you stick to the original asset palettes I think there's another table hidden away somewhere.

[Karlos]

I've updated the branch to incorporate Kalm's 030 optimised 1x1 C2P routines.

When using the generic builds (68020+), the runtime CPU detection determines if the 040 or 030 routines are appropriate.

For the 040 and 060 targeted builds, the 040 routines are always used and the 030 ones are not included in the executable.