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AChristian · 20 August 2018, 10:52

ok so lets say you:

copy tiles onto the screen

copy same tiles to the buffer

draw bobs

then the scroll register is incremented by one

so now on the screen the display has been shifted by one bit

so now copying the buffer to the screen has to be shifted by one bit

Alternatively:

copy tiles to screen

draw bobs

scroll by one pixel

draw tiles to screen shifted by one pixel (only where bobs are)

for both methods you would have to calculate the parts of the screen that have to be redrawn, so im not sure why the buffer method is faster?

20 August 2018, 10:52	#9
AChristian Registered User Join Date: Aug 2018 Location: england Posts: 24	ok so lets say you: copy tiles onto the screen copy same tiles to the buffer draw bobs then the scroll register is incremented by one so now on the screen the display has been shifted by one bit so now copying the buffer to the screen has to be shifted by one bit Alternatively: copy tiles to screen draw bobs scroll by one pixel draw tiles to screen shifted by one pixel (only where bobs are) for both methods you would have to calculate the parts of the screen that have to be redrawn, so im not sure why the buffer method is faster?