understand this roughly
understand this roughly
Right handed or left handed coord system
Lay hand flat along x axis curl fingers to y then which ever thumb points in the direction of z is the handedness
Vectors only consist of what?
Direction and magnitude where magnitude is length
How to generate a vector between two points?
Remember it as destination minus source, if we held a rubber band at a destination and pulled it to the source it would snap to destination and that's the direction of the vector.
How to do dot product of two vectors u and v, and what does it do?
u dot v = xu*xv + yu*yv + zu*zv, notice! this produces a scaler value not another vector
The equation is equal to ||u|| ||v|| cos(θ) when the angle is 0 meaning the vectors are overlapping cos(0) is 1, think unit vector, if the angle is 90 the cos(90) produces 0. the closer to 1 the more they overlap.
If the magnitudes are 1 and the angle is small we can get an equivalent dot product to two vectors with almost 90 degrees if the magnitudes are large.
what happens when you dot a vector with itself
you get the distance squared, so if you need its length/magnitude dot it with itself then square root it