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Revs on the BBC Micro

Extra tracks: Hook80Percent

Name: Hook80Percent [Show more] Type: Subroutine Category: Extra tracks Summary: Set the horizonTrackWidth to 80% of the width of the track on the horizon Deep dive: Secrets of the extra tracks Code hooks in the extra tracks
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * newContentHi calls Hook80Percent * newContentLo calls Hook80Percent
.Hook80Percent JSR Absolute8Bit \ Set A = |A|, so A contains the arc of the track at \ the horizon (i.e. the track width on the section or \ segment at the horizon) in terms of the high bytes \ (this is the same as the original code that we \ overwrote JMP Multiply80Percent \ Set the following: \ \ (A T) = 0.80 * A \ \ and return from the subroutine using a tail call EQUB &4C, &EF \ These bytes appear to be unused EQUB &53