Vector matrix multiplication

We have now implemented translation, scaling, and rotation in terms of matrices. These matrices become useful when we can apply their transformations to vectors. How do we apply a matrix transformation to a vector? The same way we do to a matrix: using matrix multiplication!

To multiply a vector and a matrix, we need to think of a vector as a matrix that has only one row or column. This leaves us with an important question, is a vec3 a matrix with one column and three rows, or three columns and one row?

Row Vector

Column Vector

Pre Multiplication

Post Multiplication

Vector matrix multiplication

If the vector is on the left side of the ...

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