src/cpml/tests/test-pair.c

   1 /* ADG - Automatic Drawing Generation
   2  * Copyright (C) 2011,2012  Nicola Fontana <ntd at entidi.it>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301, USA.
  18  */
  19
  20
  21 #include "test-internal.h"
  22 #include <math.h>
  23
  24
  25 static CpmlPair org = { .x = 0, .y = 0 };
  26 static CpmlPair nord = { .x = 0, .y = 1 };
  27 static CpmlPair diag = { .x = -3, .y = -4 };
  28 static CpmlPair diag3 = { .x = -9, .y = -12 };
  29 static CpmlPair junk = { .x = -12345.54321, .y = 9876543210.123456789 };
  30
  31
  32 static void
  33 _cpml_test_pair_basic(void)
  34 {
  35     cairo_bool_t equals;
  36     cairo_path_data_t cairo_pair;
  37     CpmlPair pair;
  38
  39     g_test_message("Careful: manipulation APIs are not guarded against NULLs");
  40
  41     equals = cpml_pair_equal(&org, &junk);
  42     g_assert(! equals);
  43
  44     equals = cpml_pair_equal(&org, NULL);
  45     g_assert(! equals);
  46
  47     equals = cpml_pair_equal(NULL, NULL);
  48     g_assert(equals);
  49
  50     cpml_pair_copy(&pair, &org);
  51     equals = cpml_pair_equal(&pair, &nord);
  52     g_assert(! equals);
  53
  54     cpml_pair_to_cairo(&nord, &cairo_pair);
  55     cpml_pair_from_cairo(&pair, &cairo_pair);
  56     equals = cpml_pair_equal(&pair, &nord);
  57     g_assert(equals);
  58
  59     cpml_pair_copy(&pair, &diag);
  60     equals = cpml_pair_equal(&pair, &nord);
  61     g_assert(! equals);
  62
  63     cpml_pair_to_cairo(&org, &cairo_pair);
  64     cpml_pair_from_cairo(&pair, &cairo_pair);
  65     equals = cpml_pair_equal(&pair, &org);
  66     g_assert(equals);
  67 }
  68
  69 static void
  70 _cpml_test_pair_transform(void)
  71 {
  72     CpmlPair pair;
  73     cairo_matrix_t matrix;
  74
  75     g_test_message("Checking for translation transformations...");
  76     cairo_matrix_init_translate(&matrix, junk.x, junk.y);
  77     cpml_pair_copy(&pair, &org);
  78     cpml_pair_transform(&pair, &matrix);
  79     g_assert_cmpfloat(pair.x, ==, junk.x);
  80     g_assert_cmpfloat(pair.y, ==, junk.y);
  81
  82     g_test_message("Checking for scaling transformations...");
  83     cairo_matrix_init_scale(&matrix, 3, 3);
  84     cpml_pair_copy(&pair, &diag);
  85     cpml_pair_transform(&pair, &matrix);
  86     g_assert_cmpfloat(pair.x, ==, diag3.x);
  87     g_assert_cmpfloat(pair.y, ==, diag3.y);
  88
  89     g_test_message("Checking for assorted transformations...");
  90     cairo_matrix_init_scale(&matrix, 3, 3);
  91     cairo_matrix_translate(&matrix, diag.x, diag.y);
  92     cairo_matrix_translate(&matrix, -junk.x, -junk.y);
  93     cpml_pair_copy(&pair, &junk);
  94     cpml_pair_transform(&pair, &matrix);
  95     g_assert_cmpfloat(pair.x, ==, diag3.x);
  96     g_assert_cmpfloat(pair.y, ==, diag3.y);
  97 }
  98
  99 static void
 100 _cpml_test_pair_distance(void)
 101 {
 102     double distance, squared_distance;
 103
 104     distance = cpml_pair_distance(NULL, NULL);
 105     g_assert_cmpfloat(distance, ==, 0);
 106
 107     distance = cpml_pair_distance(&org, NULL);
 108     g_assert_cmpfloat(distance, ==, 0);
 109
 110     distance = cpml_pair_distance(NULL, &org);
 111     g_assert_cmpfloat(distance, ==, 0);
 112
 113     distance = cpml_pair_distance(&nord, &org);
 114     g_assert_cmpfloat(distance, ==, 1);
 115
 116     squared_distance = cpml_pair_squared_distance(NULL, NULL);
 117     g_assert_cmpfloat(squared_distance, ==, 0);
 118
 119     squared_distance = cpml_pair_squared_distance(&org, NULL);
 120     g_assert_cmpfloat(squared_distance, ==, 0);
 121
 122     squared_distance = cpml_pair_squared_distance(NULL, &org);
 123     g_assert_cmpfloat(squared_distance, ==, 0);
 124
 125     squared_distance = cpml_pair_squared_distance(&nord, &org);
 126     g_assert_cmpfloat(squared_distance, ==, 1);
 127 }
 128
 129 static void
 130 _cpml_test_vector_angle(void)
 131 {
 132     double angle, angle2;
 133     CpmlVector vector;
 134
 135     angle = cpml_vector_angle(&nord);
 136     g_assert_cmpfloat(angle, ==, M_PI_2);
 137
 138     angle = M_PI_2;
 139     cpml_vector_from_angle(&vector, angle);
 140     g_assert_cmpfloat(vector.x, ==, nord.x);
 141     g_assert_cmpfloat(vector.y, ==, nord.y);
 142
 143     angle = cpml_vector_angle(&diag);
 144     angle2 = cpml_vector_angle(&diag3);
 145     g_assert_cmpfloat(angle, ==, angle2);
 146
 147     angle = 1.234567;
 148     cpml_vector_from_angle(&vector, angle);
 149     angle2 = cpml_vector_angle(&vector);
 150     g_assert_cmpfloat(angle, ==, angle2);
 151
 152     g_test_message("By convention, the vector (0,0) is considered a 0° angle");
 153     angle = cpml_vector_angle(&org);
 154     g_assert_cmpfloat(angle, ==, 0);
 155
 156     cpml_pair_copy(&vector, &org);
 157     cpml_vector_normal(&vector);
 158     g_assert_cmpfloat(vector.x, ==, org.x);
 159     g_assert_cmpfloat(vector.y, ==, org.y);
 160
 161     g_test_message("Checking cpml_vector_normal() API...");
 162     vector.x = 1;
 163     vector.y = 1;
 164     cpml_vector_normal(&vector);
 165     g_assert_cmpfloat(vector.x, ==, -1);
 166     g_assert_cmpfloat(vector.y, ==, 1);
 167
 168     cpml_vector_normal(&vector);
 169     g_assert_cmpfloat(vector.x, ==, -1);
 170     g_assert_cmpfloat(vector.y, ==, -1);
 171
 172     cpml_vector_normal(&vector);
 173     g_assert_cmpfloat(vector.x, ==, 1);
 174     g_assert_cmpfloat(vector.y, ==, -1);
 175
 176     cpml_vector_normal(&vector);
 177     g_assert_cmpfloat(vector.x, ==, 1);
 178     g_assert_cmpfloat(vector.y, ==, 1);
 179 }
 180
 181 static void
 182 _cpml_test_vector_length(void)
 183 {
 184     CpmlVector vector;
 185     double length;
 186
 187     cpml_pair_copy(&vector, &junk);
 188     cpml_vector_set_length(&vector, 0);
 189     g_assert_cmpfloat(vector.x, ==, org.x);
 190     g_assert_cmpfloat(vector.y, ==, org.y);
 191
 192     cpml_vector_set_length(&vector, 1234);
 193     g_assert_cmpfloat(vector.x, ==, org.x);
 194     g_assert_cmpfloat(vector.y, ==, org.y);
 195
 196     cpml_pair_copy(&vector, &diag3);
 197     cpml_vector_set_length(&vector, 5);
 198     g_assert_cmpfloat(vector.x, ==, diag.x);
 199     g_assert_cmpfloat(vector.y, ==, diag.y);
 200
 201     g_test_message("Using integer comparison to overcome rounding errors");
 202
 203     cpml_vector_set_length(&vector, 10);
 204     length = cpml_pair_distance(&vector, NULL);
 205     g_assert_cmpint(round(length), ==, 10);
 206
 207     cpml_vector_set_length(&vector, 5);
 208     g_assert_cmpint(round(vector.x), ==, diag.x);
 209     g_assert_cmpint(round(vector.y), ==, diag.y);
 210 }
 211
 212 static void
 213 _cpml_test_vector_transform(void)
 214 {
 215     CpmlVector vector;
 216     cairo_matrix_t matrix;
 217
 218     g_test_message("Vectors are not affected by translations");
 219     cairo_matrix_init_translate(&matrix, junk.x, junk.y);
 220     cpml_pair_copy(&vector, &org);
 221     cpml_vector_transform(&vector, &matrix);
 222     g_assert_cmpfloat(vector.x, ==, org.x);
 223     g_assert_cmpfloat(vector.y, ==, org.y);
 224
 225     g_test_message("Checking scaling transformations...");
 226     cairo_matrix_init_scale(&matrix, 3, 3);
 227     cpml_pair_copy(&vector, &diag);
 228     cpml_vector_transform(&vector, &matrix);
 229     g_assert_cmpfloat(vector.x, ==, diag3.x);
 230     g_assert_cmpfloat(vector.y, ==, diag3.y);
 231
 232     g_test_message("Checking assorted transformations...");
 233     cairo_matrix_init_scale(&matrix, 3, 3);
 234     cairo_matrix_translate(&matrix, diag.x, diag.y);
 235     cairo_matrix_translate(&matrix, -junk.x, -junk.y);
 236     cpml_pair_copy(&vector, &diag);
 237     cpml_vector_transform(&vector, &matrix);
 238     g_assert_cmpfloat(vector.x, ==, diag3.x);
 239     g_assert_cmpfloat(vector.y, ==, diag3.y);
 240 }
 241
 242
 243 int
 244 main(int argc, char *argv[])
 245 {
 246     cpml_test_init(&argc, &argv);
 247
 248     cpml_test_add_func("/cpml/pair/basic", _cpml_test_pair_basic);
 249     cpml_test_add_func("/cpml/pair/transform", _cpml_test_pair_transform);
 250     cpml_test_add_func("/cpml/pair/distance", _cpml_test_pair_distance);
 251     cpml_test_add_func("/cpml/vector/angle", _cpml_test_vector_angle);
 252     cpml_test_add_func("/cpml/vector/length", _cpml_test_vector_length);
 253     cpml_test_add_func("/cpml/vector/transform", _cpml_test_vector_transform);
 254
 255     return g_test_run();
 256 }