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A comment on Ray tracing Voxels made out of Glass. Parent comment

Re:Ray tracing Voxels made out of Glass by bugfix-66 on Sunday October 23, 2022 @09:05PM (#33311903)
The fix for the noncontiguous addition puzzle is to change

  filled = to & mask
to

  filled = to | ^mask
In other words, to OR in 1-bits so the carry can travel across the irrelevant part of the register.

Subtraction is similar:

https://bugfix-66.com/adbc40fa7c8c838d8d34bcd35525313dc91dea...

But for subtraction you want to AND in 0-bits so the borrow can travel.

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