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Aviator on the BBC Micro

Graphics: VduMove

Name: VduMove [Show more] Type: Subroutine Category: Graphics Summary: Move the graphics cursor using the standard VDU routines
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * DrawCanopy calls VduMove

Arguments: X The x-coordinate to move the graphics cursor to (0-159) Y The y-coordinate to move the graphics cursor to (0-255)
.VduMove LDA #4 \ Set A = 4 so the following VDU 25 command moves the \ graphics cursor an absolute position on-screen BNE VduPlot \ Jump to VduPlot to do the move (this BNE is \ effectively a JMP as A is never zero