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kovacm · 23 February 2015, 10:12

Hi,

I read from time to time (or to much time

) two type of arguments:

1) Atari ST has 10% faster CPU so 3D polygone games are faster
2) 3D games are ports from ST to Amiga so they do not use blitter otherwise they would be much faster on Amiga

I personally find "10% faster" argument irrelevant (unnoticeably).
but I am curios if there is any game on Amiga game that use blitter for 3D polygon fill?

or, even better: does somebody, with knowledge, can make explanation how much theoretical gain could be in game (not in demos!) using blitter for poly-fill?

I have no knowledge about blitter: e.g. how much time would you spent on setting it up for fill vs filling with CPU alone? How much time is left for CPU while blitter doing fills (in case that there is no fast ram, and case with fast ram)...
Amiga 1200 case: if there is FastRAM, CPU could calculate 3D vertices while blitter filling polygons so filling could be almost "free"? Can copper somehow help with setting up blitter...?

I would really appreciate if someone could made technical analyse.

---
btw all 512KB expansion for Amiga 500 back in 80s and 90s were chipram? right? FastRAM was not common expansion in Amiga world until Amiga 1200?

23 February 2015, 10:12	#1
kovacm Banned Join Date: Jan 2012 Location: Serbia Posts: 275	Using blitter for filling 3D polygons Hi, I read from time to time (or to much time ) two type of arguments: 1) Atari ST has 10% faster CPU so 3D polygone games are faster 2) 3D games are ports from ST to Amiga so they do not use blitter otherwise they would be much faster on Amiga I personally find "10% faster" argument irrelevant (unnoticeably). but I am curios if there is any game on Amiga game that use blitter for 3D polygon fill? or, even better: does somebody, with knowledge, can make explanation how much theoretical gain could be in game (not in demos!) using blitter for poly-fill? I have no knowledge about blitter: e.g. how much time would you spent on setting it up for fill vs filling with CPU alone? How much time is left for CPU while blitter doing fills (in case that there is no fast ram, and case with fast ram)... Amiga 1200 case: if there is FastRAM, CPU could calculate 3D vertices while blitter filling polygons so filling could be almost "free"? Can copper somehow help with setting up blitter...? I would really appreciate if someone could made technical analyse. --- btw all 512KB expansion for Amiga 500 back in 80s and 90s were chipram? right? FastRAM was not common expansion in Amiga world until Amiga 1200?