Pekka Paalanen | 668ca37 | 2012-01-12 14:30:47 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright © 2011 Intel Corporation |
| 3 | * |
| 4 | * Permission to use, copy, modify, distribute, and sell this software and |
| 5 | * its documentation for any purpose is hereby granted without fee, provided |
| 6 | * that the above copyright notice appear in all copies and that both that |
| 7 | * copyright notice and this permission notice appear in supporting |
| 8 | * documentation, and that the name of the copyright holders not be used in |
| 9 | * advertising or publicity pertaining to distribution of the software |
| 10 | * without specific, written prior permission. The copyright holders make |
| 11 | * no representations about the suitability of this software for any |
| 12 | * purpose. It is provided "as is" without express or implied warranty. |
| 13 | * |
| 14 | * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS |
| 15 | * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| 16 | * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY |
| 17 | * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER |
| 18 | * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF |
| 19 | * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| 20 | * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 21 | */ |
| 22 | |
| 23 | #include <string.h> |
| 24 | #include <stdlib.h> |
| 25 | #include <GLES2/gl2.h> |
| 26 | #include <wayland-server.h> |
| 27 | |
| 28 | #include "matrix.h" |
| 29 | |
| 30 | /* |
| 31 | * Matrices are stored in column-major order, that is the array indices are: |
| 32 | * 0 4 8 12 |
| 33 | * 1 5 9 13 |
| 34 | * 2 6 10 14 |
| 35 | * 3 7 11 15 |
| 36 | */ |
| 37 | |
| 38 | WL_EXPORT void |
| 39 | weston_matrix_init(struct weston_matrix *matrix) |
| 40 | { |
| 41 | static const struct weston_matrix identity = { |
| 42 | { 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1 } |
| 43 | }; |
| 44 | |
| 45 | memcpy(matrix, &identity, sizeof identity); |
| 46 | } |
| 47 | |
| 48 | /* m <- n * m, that is, m is multiplied on the LEFT. */ |
| 49 | WL_EXPORT void |
| 50 | weston_matrix_multiply(struct weston_matrix *m, const struct weston_matrix *n) |
| 51 | { |
| 52 | struct weston_matrix tmp; |
| 53 | const GLfloat *row, *column; |
| 54 | div_t d; |
| 55 | int i, j; |
| 56 | |
| 57 | for (i = 0; i < 16; i++) { |
| 58 | tmp.d[i] = 0; |
| 59 | d = div(i, 4); |
| 60 | row = m->d + d.quot * 4; |
| 61 | column = n->d + d.rem; |
| 62 | for (j = 0; j < 4; j++) |
| 63 | tmp.d[i] += row[j] * column[j * 4]; |
| 64 | } |
| 65 | memcpy(m, &tmp, sizeof tmp); |
| 66 | } |
| 67 | |
| 68 | WL_EXPORT void |
| 69 | weston_matrix_translate(struct weston_matrix *matrix, GLfloat x, GLfloat y, GLfloat z) |
| 70 | { |
| 71 | struct weston_matrix translate = { |
| 72 | { 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, x, y, z, 1 } |
| 73 | }; |
| 74 | |
| 75 | weston_matrix_multiply(matrix, &translate); |
| 76 | } |
| 77 | |
| 78 | WL_EXPORT void |
| 79 | weston_matrix_scale(struct weston_matrix *matrix, GLfloat x, GLfloat y, GLfloat z) |
| 80 | { |
| 81 | struct weston_matrix scale = { |
| 82 | { x, 0, 0, 0, 0, y, 0, 0, 0, 0, z, 0, 0, 0, 0, 1 } |
| 83 | }; |
| 84 | |
| 85 | weston_matrix_multiply(matrix, &scale); |
| 86 | } |
| 87 | |
| 88 | /* v <- m * v */ |
| 89 | WL_EXPORT void |
| 90 | weston_matrix_transform(struct weston_matrix *matrix, struct weston_vector *v) |
| 91 | { |
| 92 | int i, j; |
| 93 | struct weston_vector t; |
| 94 | |
| 95 | for (i = 0; i < 4; i++) { |
| 96 | t.f[i] = 0; |
| 97 | for (j = 0; j < 4; j++) |
| 98 | t.f[i] += v->f[j] * matrix->d[i + j * 4]; |
| 99 | } |
| 100 | |
| 101 | *v = t; |
| 102 | } |