Avoid division in JD calc, when possible #17945
Merged
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Description
There's no need for a division, if the axis is not limiting. This solution typically requires three to four multiplications instead of three to four divisions. In the worst case (all axis limiting in descending order), four divisions + four multiplications can be necessary, but that should be exceedingly rare.
Technically, the
if (unit_vec[idx]) {
check is not required anymore, since a divide by zero is avoided bylimit_value * ABS(unit_vec[idx]) > settings.max_acceleration_mm_per_s2[idx]
. I kept the check nonetheless, to avoid another multiplication when possible.Benefits
Typically saves three to four divides per block planned and only requires three to four multiplications in return.
Related Issues
None.