Quote:
Originally Posted by dlfrsilver
The CPU speed clock is mostly is a "myth" (remember what Mcoder said on Atari Forum, that it was totally irrelevant).
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I'm not talking about the clock speed. I'm talking about the cycle count per masked word on screen. 8 cycles is best case on the Amiga using the $CA cookie cut method. That's during horizontal and vertical blank when there's no competing DMA activity. What do you think the CPU cycle count is when say 4 low res bitplanes are used on the Amiga during a blit? Hint: It's way more than 8.
Anima's method on the STe doesn't mask at all. It's a line by line copy taking advantage of the intelligent end masks. It's 8 cycles best case and 12 cycles worst case per word. That's the same speed as the best case on the Amiga and it's considerably faster than the worst case when there's competing DMA activity. That's before you take into account the 11% faster clock speed.
There's blitter restart overhead on the Ste but it still probably runs about 50% faster than the brute force method I used in my ST blitter intro.