Howdy, Would anyone know any good tutorials (or just a quick answer) about matrix interpolation? I am refering to creating a matrix based upon two key-frame matrices and a time. This will usually happen when you have two key frames for an animation, and only have a final concated matrix for each frame. The translation part is easy to pull out of the matrix, but everything else seems a little tricky. Any help or pointers to any info. would be great! Thanks!

Using D3DX, matrix interpolation is actually quite fast and easy:

// TotalTime = length between 1st and 2nd matrices
// InterpolateTime = time from 0.0 to 1.0
D3DXMATRIX Matrix1, Matrix2;
float TotalTime, InterpolateTime;
D3DXMATRIX Result;

Result = Matrix1 + ((Matrix2 - Matrix1) / TotalTime * (InterpolateTime * TotalTime));

Jim Adams

Thanks!