Instead of moving the object to the origin in order to rotate, can we move the center of rotation to where we need instead?
tplatina
I guess it is just as several transform matrix working together which gives you a single transform that realizes this function. But the essence is still moving to center and then move back. Though I am wondering too if there is this "magic matrix" formula that we can simply use instead of calculating the product matrix step by step?
miyehn
@hii When specifying rotation in the form of this commonly used matrix format, the center of rotation is always the origin. Any matrix that does rotation not around the origin is essentially doing this- move the object to the origin -> rotate it -> move it back. (equivalent to the product of 3 matrices)
It does save some computation to store this multiplied matrix though, if the entire rotation around some point is going to be applied many times.
Instead of moving the object to the origin in order to rotate, can we move the center of rotation to where we need instead?
I guess it is just as several transform matrix working together which gives you a single transform that realizes this function. But the essence is still moving to center and then move back. Though I am wondering too if there is this "magic matrix" formula that we can simply use instead of calculating the product matrix step by step?
@hii When specifying rotation in the form of this commonly used matrix format, the center of rotation is always the origin. Any matrix that does rotation not around the origin is essentially doing this- move the object to the origin -> rotate it -> move it back. (equivalent to the product of 3 matrices)
It does save some computation to store this multiplied matrix though, if the entire rotation around some point is going to be applied many times.