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Revs on the BBC Micro

Dashboard: shortAxis

Name: shortAxis [Show more] Type: Variable Category: Dashboard Summary: Code modifications for the DrawDashboardLine line-drawing routine
Context: See this variable in context in the source code References: This variable is used as follows: * DrawDashboardLine calls shortAxis

When drawing a line, the short axis is only stepped along when the slope error adds up to a whole pixel, so this steps along the shorter axis of the line's vector. See the DrawDashboardLine routine for details.
.shortAxis INX \ V = 0, INX and DEY = Steep slope, right and up DEY \ V = 1, DEY and INX = Shallow slope, right and up INY \ V = 2, INY and INX = Shallow slope, right and down INX \ V = 3, INX and INY = Steep slope, right and down DEX \ V = 4, DEX and INY = Steep slope, left and down INY \ V = 5, INY and DEX DEY \ V = 6, DEY and DEX DEX \ V = 7, DEX and DEY