Fix rendering of 'AN3' trick on Apple IIe#32
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dbalsom wants to merge 1 commit intoThorstenBr:masterfrom
Open
Fix rendering of 'AN3' trick on Apple IIe#32dbalsom wants to merge 1 commit intoThorstenBr:masterfrom
dbalsom wants to merge 1 commit intoThorstenBr:masterfrom
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This PR aims to fix rendering of the 'AN3 trick' used by Prince of Persia and some demos.
By using AN3 without 80 column mode, a one-pixel shift in the graphics output is produced that causes a 90 degree phase shift relative to the color carrier which changes the artifact colors produced on a composite display.
This was used as a quick palette switch effect.
A2DVI was rendering DHGR mode after only checking AN3; we add a check for 80 column mode as well. Then additional logic is used to shift the serializer output by 1 bit in normal hires mode to create the 90 degree phase change.