koobas.hobune.stream
Math behind transform.TransformDirection?
I know TransformDirection can convert local to world coordinates. Can can tell me how the math behind the process works?
The transform of a gameobject has a matrix storing information like position, rotation and scale. TransformDirection multiplies the input vector with the transform's matrix and returns the result. InverseTransformDirection multiplies the input vector with the transpose of the transform's matrix. In 3d it is a 4 by 4 matrix, in 2d 2 by 2 matrices are used.
thank you . may be i should google a method by c or c++ about the process. also to find the same process with mono game project, because it have open source code.
This is wrong. What you are describing is TransformPoint, not TransformDirection.
You have to decompose the rotation component of the matrix.
There is a Matrix4x4.rotation property. It returns a Quaternion. Simply rotate your direction vector with that Quaternion.
