1 /* #include "HEADERS.h" */
2 /* Copyright 1988, Brown Computer Graphics Group. All Rights Reserved. */
4 /* --------------------------------------------------------------------------
5 * This file contains routines that operate solely on matrices.
6 * -------------------------------------------------------------------------*/
14 # ifndef HAVE_STL_SGI_PORT
15 # include <memory.h> /* required for memset() and memcpy() */
20 #include <Math/mat3defs.h>
24 /* #include "macros.h" */
26 /* -------------------------- Static Routines ---------------------------- */
28 /* ------------------------- Internal Routines --------------------------- */
30 /* -------------------------- Public Routines ---------------------------- */
33 #if !defined( USE_XTRA_MAT3_INLINES )
36 * Sets a matrix to identity.
40 MAT3identity (register MAT3mat mat)
44 #ifdef USE_MEM /* WIN32 */
45 memset(mat, 0x00, sizeof(MAT3mat));
47 bzero (mat, sizeof(MAT3mat));
50 for (i = 0; i < 4; i++)
55 * Sets a matrix to zero.
59 MAT3zero (MAT3mat mat)
61 #ifdef USE_MEM /* WIN32 */
62 memset(mat,0x00, sizeof(MAT3mat));
64 bzero (mat, sizeof(MAT3mat));
70 * Copies one matrix to another.
74 MAT3copy(MAT3mat to, MAT3mat from)
76 #ifdef USE_MEM /* WIN32 */
77 memcpy(to, from, sizeof(MAT3mat));
79 bcopy(from, to, sizeof(MAT3mat));
84 * This multiplies two matrices, producing a third, which may the same as
85 * either of the first two.
89 MAT3mult (double (*result_mat)[4], register double (*mat1)[4], register double (*mat2)[4])
94 for (i = 0; i < 4; i++)
95 for (j = 0; j < 4; j++)
96 tmp_mat[i][j] = (mat1[i][0] * mat2[0][j] +
97 mat1[i][1] * mat2[1][j] +
98 mat1[i][2] * mat2[2][j] +
99 mat1[i][3] * mat2[3][j]);
100 MAT3copy (result_mat, tmp_mat);
102 #endif // !defined( USE_XTRA_MAT3_INLINES )
105 * This returns the transpose of a matrix. The result matrix may be
106 * the same as the one to transpose.
110 MAT3transpose (double (*result_mat)[4], register double (*mat)[4])
115 for (i = 0; i < 4; i++)
116 for (j = 0; j < 4; j++)
117 tmp_mat[i][j] = mat[j][i];
119 MAT3copy (result_mat, tmp_mat);
124 * This prints the given matrix to the given file pointer.
128 MAT3print(double (*mat)[4], FILE *fp)
130 MAT3print_formatted(mat, fp, CNULL, CNULL, CNULL, CNULL);
134 * This prints the given matrix to the given file pointer.
135 * use the format string to pass to fprintf. head and tail
136 * are printed at the beginning and end of each line.
140 MAT3print_formatted(double (*mat)[4], FILE *fp, char *title, char *head, char *format, char *tail)
144 /* This is to allow this to be called easily from a debugger */
145 if (fp == NULL) fp = stderr;
147 if (title == NULL) title = "MAT3 matrix:\n";
148 if (head == NULL) head = " ";
149 if (format == NULL) format = "%#8.4lf ";
150 if (tail == NULL) tail = "\n";
152 (void) fprintf(fp, title);
154 for (i = 0; i < 4; i++) {
155 (void) fprintf(fp, head);
156 for (j = 0; j < 4; j++) (void) fprintf(fp, format, mat[i][j]);
157 (void) fprintf(fp, tail);