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Elite on the BBC Micro and NES

Maths (Geometry): SCALEX

[BBC Master version]

Name: SCALEX [Show more] Type: Subroutine Category: Maths (Geometry) Summary: Scale the x-coordinate in A
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * TT103 calls SCALEX * TT14 calls SCALEX * TT22 calls SCALEX

This routine (and the related SCALEY and SCALEY2 routines) are called from various places in the code to scale the value in A. This scaling can be changed by changing these routines (for example, by changing an RTS to an LSR A). This code is left over from the conversion to other platforms, where the scale factor might need to be different.
.SCALEX RTS \ Return from the subroutine