Blender Git Loki

Fix #29743: Video sequencer wipe effect bug

Blur width used to be calculated quite strange depending on current angle.
Also, it used to be using wrong formula to calculate distance between
current point and boundary line which made blur width almost useless.

Now actual blur width is doesn't depend on angle and use corrected formula
for distance calculation which makes blur width slider behaves more
predictable.

This commit might make old files using wipe+blur be rendered a bit differently,
but don't think it's indeed issue because old behavior was crappy to setup
something useful so don't think this setup was used a lot.