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Revs on the BBC Micro

Dashboard: stepAxis

Name: stepAxis [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 stepAxis

When drawing a line, we step along the longer axis of the line's vector by one pixel for loop around the line-drawing routine. See the DrawDashboardLine routine for details.
.stepAxis DEY \ V = 0, INX and DEY = Steep slope, right and up INX \ V = 1, DEY and INX = Shallow slope, right and up INX \ V = 2, INY and INX = Shallow slope, right and down INY \ V = 3, INX and INY = Steep slope, right and down INY \ V = 4, DEX and INY = Steep slope, left and down DEX \ V = 5, INY and DEX DEX \ V = 6, DEY and DEX DEY \ V = 7, DEX and DEY EQUB &18, &EA EQUB &EA, &18 EQUB &18, &EA EQUB &EA, &18