Strafing and vector cross products

Troubleshooting General Help
1

Hey everyone,



I’m currently working on strafing by taking the cross-product of the look direction vector and (0, 1, 0), but I’m unsure which direction (left or right) the cross-product will yield. Is there a solid way to figure this out without trial and errors?



thanks!

jW

2

Where do you get your look direction? (Camera already provides a left vector is why I ask…)

3

The look direction is a property of the data type I’m strafing. The camera is separate. (thanks for the speedy response!)

4

…but to answer your question anyway… it depends on which order you are doing the cross product, up.cross(look) or look.cross(up). I think look.cross(up) points right but it’s easy to test… if new Vector3f( 0, 0, -1 ).cross( new Vector3f( 0, 1, 0 ) ).x == 1 then the vector points right.

5

Thanks a bunch, that was incredibly helpful! Happy coding!