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Aviator on the BBC Micro

Graphics: yLookupLo

Name: yLookupLo [Show more] Type: Variable Category: Graphics Summary: Lookup table for converting pixel y-coordinate to low byte of screen address Deep dive: Converting pixel coordinates to screen addresses
Context: See this variable in context in the source code References: This variable is used as follows: * DrawCanopyLine (Part 1 of 9) uses yLookupLo * DrawVectorLine (Part 3 of 3) uses yLookupLo
.yLookupLo FOR I%, 19, 0, -1 EQUB LO(&5800 + (I% * &138)) NEXT FOR I%, 31, 20, -1 EQUB LO(&5800 + (I% * &138)) NEXT