matrix-test.c revision 1176bdada62cabc6ec4b0308a930e83b679d5d36 
1/*
2 * Copyright © 2012 Siarhei Siamashka <siarhei.siamashka@gmail.com>
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 */
23
24#include "utils.h"
25#include <assert.h>
26#include <stdlib.h>
27#include <stdio.h>
28#include <math.h>
29
30#ifdef HAVE_FLOAT128
31
32#define pixman_fixed_to_float128(x) (((__float128)(x)) / 65536.0Q)
33
34typedef struct { __float128 v[3]; } pixman_vector_f128_t;
35typedef struct { __float128 m[3][3]; } pixman_transform_f128_t;
36
37pixman_bool_t
38pixman_transform_point_f128 (const pixman_transform_f128_t *t,
39                             const pixman_vector_f128_t    *v,
40                             pixman_vector_f128_t          *result)
41{
42    int i;
43    for (i = 0; i < 3; i++)
44    {
45        result->v[i] = t->m[i][0] * v->v[0] +
46                       t->m[i][1] * v->v[1] +
47                       t->m[i][2] * v->v[2];
48    }
49    if (result->v[2] != 0)
50    {
51        result->v[0] /= result->v[2];
52        result->v[1] /= result->v[2];
53        result->v[2] = 1;
54        return TRUE;
55    }
56    else
57    {
58        return FALSE;
59    }
60}
61
62pixman_bool_t does_it_fit_fixed_48_16 (__float128 x)
63{
64    if (x >= 65536.0Q * 65536.0Q * 32768.0Q)
65        return FALSE;
66    if (x <= -65536.0Q * 65536.0Q * 32768.0Q)
67        return FALSE;
68    return TRUE;
69}
70
71#endif
72
73uint32_t
74test_matrix (int testnum, int verbose)
75{
76    uint32_t crc32 = 0;
77    int i, j, k;
78    pixman_bool_t is_affine;
79
80    prng_srand (testnum);
81
82    for (i = 0; i < 100; i++)
83    {
84        pixman_bool_t           transform_ok;
85        pixman_transform_t      ti;
86        pixman_vector_48_16_t   vi, result_i;
87#ifdef HAVE_FLOAT128
88        pixman_transform_f128_t tf;
89        pixman_vector_f128_t    vf, result_f;
90#endif
91        prng_randmemset (&ti, sizeof(ti), 0);
92        prng_randmemset (&vi, sizeof(vi), 0);
93
94        for (j = 0; j < 3; j++)
95        {
96            /* make sure that "vi" contains 31.16 fixed point data */
97            vi.v[j] >>= 17;
98            /* and apply random shift */
99            if (prng_rand_n (3) == 0)
100                vi.v[j] >>= prng_rand_n (46);
101        }
102
103        if (prng_rand_n (2))
104        {
105            /* random shift for the matrix */
106            for (j = 0; j < 3; j++)
107                for (k = 0; k < 3; k++)
108                    ti.matrix[j][k] >>= prng_rand_n (30);
109        }
110
111        if (prng_rand_n (2))
112        {
113            /* affine matrix */
114            ti.matrix[2][0] = 0;
115            ti.matrix[2][1] = 0;
116            ti.matrix[2][2] = pixman_fixed_1;
117        }
118
119        if (prng_rand_n (2))
120        {
121            /* cartesian coordinates */
122            vi.v[2] = pixman_fixed_1;
123        }
124
125        is_affine = (ti.matrix[2][0] == 0 && ti.matrix[2][1] == 0 &&
126                     ti.matrix[2][2] == pixman_fixed_1 &&
127                     vi.v[2] == pixman_fixed_1);
128
129        transform_ok = TRUE;
130        if (is_affine && prng_rand_n (2))
131            pixman_transform_point_31_16_affine (&ti, &vi, &result_i);
132        else
133            transform_ok = pixman_transform_point_31_16 (&ti, &vi, &result_i);
134
135        crc32 = compute_crc32 (crc32, &result_i, sizeof(result_i));
136
137#ifdef HAVE_FLOAT128
138        /* compare with a reference 128-bit floating point implementation */
139        for (j = 0; j < 3; j++)
140        {
141            vf.v[j] = pixman_fixed_to_float128 (vi.v[j]);
142            for (k = 0; k < 3; k++)
143            {
144                tf.m[j][k] = pixman_fixed_to_float128 (ti.matrix[j][k]);
145            }
146        }
147
148        if (pixman_transform_point_f128 (&tf, &vf, &result_f))
149        {
150            if (transform_ok ||
151                (does_it_fit_fixed_48_16 (result_f.v[0]) &&
152                 does_it_fit_fixed_48_16 (result_f.v[1]) &&
153                 does_it_fit_fixed_48_16 (result_f.v[2])))
154            {
155                for (j = 0; j < 3; j++)
156                {
157                    double diff = fabs (result_f.v[j] -
158                                        pixman_fixed_to_float128 (result_i.v[j]));
159
160                    if (is_affine && diff > (0.51 / 65536.0))
161                    {
162                        printf ("%d:%d: bad precision for affine (%.12f)\n",
163                               testnum, i, diff);
164                        abort ();
165                    }
166                    else if (diff > (0.71 / 65536.0))
167                    {
168                        printf ("%d:%d: bad precision for projective (%.12f)\n",
169                               testnum, i, diff);
170                        abort ();
171                    }
172                }
173            }
174        }
175#endif
176    }
177    return crc32;
178}
179
180int
181main (int argc, const char *argv[])
182{
183    return fuzzer_test_main ("matrix", 20000,
184			     0xBEBF98C3,
185			     test_matrix, argc, argv);
186}
187