Notices by :ihavenomouth: (inginsub@clubcyberia.co), page 40
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@crunklord420
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@crunklord420 maybe your code finishes after the v-blank ends, and you're forced to sit through the scan period (also missing h-blanks with all the comparisons)
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@crunklord420 what exactly do you use this code for?
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@crunklord420 The short explanation: you can only write to VGA memory during blanking periods, because during scan time the bus is busy reading, any write operation stalls and the CPU does nothing; VGA memory is main memory-mapped, obviously, but data transfer is limited by the VGA transfer rate. I think v-blank is not long enough to write the entire buffer, you have to encroach on the active frame time and use h-blanks too, at least in the 640x480 16-color mode. Finding dirty pixels makes sense if you only need to update a small portion of the screen, but if the entire framebuffer is to be redrawn, you're wasting precious microseconds on branching and call MOVSQ for each of the 4800*4 qwords individually, only losing time, because you still need to write every pixel, but now you also need to initialize the pipeline for the next MOVSQ again. All of that may cause the CPU to miss the next VGA bus 'tick', under utilize the V-blank and use more H-blanks than necessary. If you consistently waste all H-blanks, you get severe framerate drops.
My guess is vmware takes some liberties with VGA hardware emulation to produce realistic performance, and virtualbox and qemu try to emulate it 'faithfully', which doesn't quite work out.
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@crunklord420 why are you updating DC and not the VGA buffer directly?
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@crunklord420 what does the third loop do? do you update the buffer dword by dword instead of line by line? try using memcpy unconditionally
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@crunklord420 Don't, just assume that you have to redraw the entire screen every frame. It's likely true anyway, except if the camera doesn't move at all.
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@crunklord420 yes, the super computers we operate will literally drop 60 frames because you replaced REP STOSQ with a bunch of other instructions. I think you're too used to the optimization modern compilers provide for free, the HolyC compiler doesn't optimize shit
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We are in the middle of a worldwide common cold pandemic
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@RustyCrab just Damus, from apple app store
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I think I said that zaps violate appstore's ToS back in February
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@sneeden kitchen or bathroom?
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@sarvo
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@harriettmb @Ponddrop what the hell is this thing
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@blaaablaaaa @coolboymew I must've missed it
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@coolboymew ok, I'm sold
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I have a friend who is a big fan of Gaspar Noe. Turns out he has only watched the rape scene from Irreversible, 20+ times.
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@cassidyclown can you revoke all my oauth tokens? I can't log out
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@cassidyclown @mint
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@cassidyclown looks like it did federate at least to cum.salon
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