Graphics: xLookupHi

       Name: xLookupHi                                               [Show more]
       Type: Variable
   Category: Graphics
    Summary: Lookup table for converting pixel x-coordinate to high byte of
             screen address
    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * DrawCanopyLine (Part 1 of 9) uses xLookupHi
             * DrawVectorLine (Part 3 of 3) uses xLookupHi


 Each character block contains 8 bytes, so this lookup table lets us convert a
 pixel x-coordinate to a 16-bit address offset from the beginning of the
 character row. We could achieve the same effect by simply multiplying the
 pixel x-coordinate by 8, but using a lookup table is quicker than doing the
 multiplication.


.xLookupHi

 FOR I%, 0, 39

  EQUB HI(I% * 8)

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