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Aviator on the BBC Micro

Graphics: FillCanopy

Name: FillCanopy [Show more] Type: Subroutine Category: Graphics Summary: Fill the canopy with a specified colour, leaving the canopy edges alone
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * Crash calls FillCanopy

Arguments: X The colour to fill the canopy with
.FillCanopy TXA \ Copy the colour into X LDX #19 \ Set R = 19, so we clear 19 character rows (the whole STX R \ canopy view except for the top row containing the \ canopy edge) LDY #HI(row1_block1_0) \ Set (Y X) to the screen address for row 1, block 1 LDX #LO(row1_block1_0) \ Fall through into FillCanopyRows to fill the canopy \ view, from the top row to the bottom, avoiding the top \ and side edges