/*****************************************************************************
 Compute a general 4x4 rotation matrix for 3-D rotation about a center point
                      For CS480 Programming Assignment 3
******************************************************************************
    Author: 
******************************************************************************/

#include <math.h> 

/* 
Write a routine that constructs the 4x4 homogeneous transform for
rotation about a center point.  

The rotations should be applied in order: x rotation first, y rotation
second, and z rotation third.  

Note that a 4x4 matrix multiplication has been provided if you wish 
to use it for the assignment.
*/

compute_rotation(angles,center,M)
float *angles;                /* 3 angles of rotation: angles[0] is x rotation, angles[1] is y, etc. */
float *center;                /* the center for the rotation */
float M[4][4];                /* the resulting rotation matrix */
{
}  

/* 4x4 matrix multiplication routine */
matrix_multiply_4x4(R,A,B)
float R[4][4];               /* result */
float A[4][4],B[4][4];       /* two matrices to be multiplied */
{
  int i,j,k;
  float a;

  for(i=0;i<4;++i)
    for(j=0;j<4;++j)
      {
	for(k=0,a=0.0;k<4;++k)
	  a += A[i][k]*B[k][j];
	R[i][j] = a;
      }
}