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/*
* Copyright © 2011 Intel Corporation
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of the copyright holders not be used in
* advertising or publicity pertaining to distribution of the software
* without specific, written prior permission. The copyright holders make
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
* CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <string.h>
#include <stdlib.h>
#include <GLES2/gl2.h>
#include <wayland-server.h>
#include "matrix.h"
/*
* Matrices are stored in column-major order, that is the array indices are:
* 0 4 8 12
* 1 5 9 13
* 2 6 10 14
* 3 7 11 15
*/
WL_EXPORT void
weston_matrix_init(struct weston_matrix *matrix)
{
static const struct weston_matrix identity = {
{ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1 }
};
memcpy(matrix, &identity, sizeof identity);
}
/* m <- n * m, that is, m is multiplied on the LEFT. */
WL_EXPORT void
weston_matrix_multiply(struct weston_matrix *m, const struct weston_matrix *n)
{
struct weston_matrix tmp;
const GLfloat *row, *column;
div_t d;
int i, j;
for (i = 0; i < 16; i++) {
tmp.d[i] = 0;
d = div(i, 4);
row = m->d + d.quot * 4;
column = n->d + d.rem;
for (j = 0; j < 4; j++)
tmp.d[i] += row[j] * column[j * 4];
}
memcpy(m, &tmp, sizeof tmp);
}
WL_EXPORT void
weston_matrix_translate(struct weston_matrix *matrix, GLfloat x, GLfloat y, GLfloat z)
{
struct weston_matrix translate = {
{ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, x, y, z, 1 }
};
weston_matrix_multiply(matrix, &translate);
}
WL_EXPORT void
weston_matrix_scale(struct weston_matrix *matrix, GLfloat x, GLfloat y, GLfloat z)
{
struct weston_matrix scale = {
{ x, 0, 0, 0, 0, y, 0, 0, 0, 0, z, 0, 0, 0, 0, 1 }
};
weston_matrix_multiply(matrix, &scale);
}
/* v <- m * v */
WL_EXPORT void
weston_matrix_transform(struct weston_matrix *matrix, struct weston_vector *v)
{
int i, j;
struct weston_vector t;
for (i = 0; i < 4; i++) {
t.f[i] = 0;
for (j = 0; j < 4; j++)
t.f[i] += v->f[j] * matrix->d[i + j * 4];
}
*v = t;
}
WL_EXPORT int
weston_matrix_invert(struct weston_matrix *inverse,
const struct weston_matrix *matrix)
{
return -1; /* fail */
}
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