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I think I have asked this question before. But does anyone have a really fast Alpha Blending routine which I can use with FL? FL's AB routine is quite slow

what does alpha blending mean.

I think it has to do with transparency in sprites,
alpha channel=trans´parency channel

Hmm...If you use WinXP then if you notice that when you select multiple files in Win Explorer by dragging a rectangular square then you will see translucent background with icons. This is an example of alpha blending.

When you want to merge two functions, and you want the result to be in the same range as these two functions, you will say:

Result = Alpha * F1 + (1-Alpha)*F2, with 0<=Alpha <=1

If Alpha = 0 then Result = F2, If Alpha = 1 then Result = F1. If Alpha is in-between, you get something in between...

You can apply that to RGB colours:

R = Alpha * R1 + (1-Alpha)*R2
G = Alpha * G1 + (1-Alpha)*G2
B = Alpha * B1 + (1-Alpha)*B2

And you are sure that R, G and B will always remain in the 0-255 range, while the blend is controled by the value of Alpha.

That's the technique used for transparencies, but also reflections (I used something of that kind in TC-Ray).

But you havent answered my underlying question. Is there any prog/add on which will allow me to get faster alpha blending and that can be used with FL?

8 bit, or true/high color?

Specifically for High Color(16bit)

I have downloaded FL a while ago, but I never took time to study it (my own TC-Lib being more adapted to what I do). The reason why I never got into it is that I have never seen the source code: there are only .OBJ files in the zip I have.

Anyway, tweaking the formulas for a fast bit-based routine, compliant with the above-mentioned formulas, must not be very difficult: R, G & B are "single-byte integers", Alpha can also be considered as an single-byte integer (Alpha*255 has a 0-255 range).

Sorry I cannot help more... Maybe you could give the input/output of what you wanna do, and someone could think about an ASM routine that would match the spec...

UGL has one but it's undocumented and therefore I think unfinished... it didn't work extremely well in mode 13h, but I haven't tested the rest =P