MatrixTest.cpp revision e40591d5484762067f976d979c506f126c7779e1
1 2/* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8#include "Test.h" 9#include "SkMath.h" 10#include "SkMatrix.h" 11#include "SkRandom.h" 12 13static bool nearly_equal_scalar(SkScalar a, SkScalar b) { 14 // Note that we get more compounded error for multiple operations when 15 // SK_SCALAR_IS_FIXED. 16#ifdef SK_SCALAR_IS_FLOAT 17 const SkScalar tolerance = SK_Scalar1 / 200000; 18#else 19 const SkScalar tolerance = SK_Scalar1 / 1024; 20#endif 21 22 return SkScalarAbs(a - b) <= tolerance; 23} 24 25static bool nearly_equal(const SkMatrix& a, const SkMatrix& b) { 26 for (int i = 0; i < 9; i++) { 27 if (!nearly_equal_scalar(a[i], b[i])) { 28 printf("not equal %g %g\n", (float)a[i], (float)b[i]); 29 return false; 30 } 31 } 32 return true; 33} 34 35static bool are_equal(skiatest::Reporter* reporter, 36 const SkMatrix& a, 37 const SkMatrix& b) { 38 bool equal = a == b; 39 bool cheapEqual = a.cheapEqualTo(b); 40 if (equal != cheapEqual) { 41#if SK_SCALAR_IS_FLOAT 42 if (equal) { 43 bool foundZeroSignDiff = false; 44 for (int i = 0; i < 9; ++i) { 45 float aVal = a.get(i); 46 float bVal = b.get(i); 47 int aValI = *SkTCast<int*>(&aVal); 48 int bValI = *SkTCast<int*>(&bVal); 49 if (0 == aVal && 0 == bVal && aValI != bValI) { 50 foundZeroSignDiff = true; 51 } else { 52 REPORTER_ASSERT(reporter, aVal == bVal && aValI == aValI); 53 } 54 } 55 REPORTER_ASSERT(reporter, foundZeroSignDiff); 56 } else { 57 bool foundNaN = false; 58 for (int i = 0; i < 9; ++i) { 59 float aVal = a.get(i); 60 float bVal = b.get(i); 61 int aValI = *SkTCast<int*>(&aVal); 62 int bValI = *SkTCast<int*>(&bVal); 63 if (sk_float_isnan(aVal) && aValI == bValI) { 64 foundNaN = true; 65 } else { 66 REPORTER_ASSERT(reporter, aVal == bVal && aValI == bValI); 67 } 68 } 69 REPORTER_ASSERT(reporter, foundNaN); 70 } 71#else 72 REPORTER_ASSERT(reporter, false); 73#endif 74 } 75 return equal; 76} 77 78static bool is_identity(const SkMatrix& m) { 79 SkMatrix identity; 80 identity.reset(); 81 return nearly_equal(m, identity); 82} 83 84static void test_matrix_recttorect(skiatest::Reporter* reporter) { 85 SkRect src, dst; 86 SkMatrix matrix; 87 88 src.set(0, 0, SK_Scalar1*10, SK_Scalar1*10); 89 dst = src; 90 matrix.setRectToRect(src, dst, SkMatrix::kFill_ScaleToFit); 91 REPORTER_ASSERT(reporter, SkMatrix::kIdentity_Mask == matrix.getType()); 92 REPORTER_ASSERT(reporter, matrix.rectStaysRect()); 93 94 dst.offset(SK_Scalar1, SK_Scalar1); 95 matrix.setRectToRect(src, dst, SkMatrix::kFill_ScaleToFit); 96 REPORTER_ASSERT(reporter, SkMatrix::kTranslate_Mask == matrix.getType()); 97 REPORTER_ASSERT(reporter, matrix.rectStaysRect()); 98 99 dst.fRight += SK_Scalar1; 100 matrix.setRectToRect(src, dst, SkMatrix::kFill_ScaleToFit); 101 REPORTER_ASSERT(reporter, 102 (SkMatrix::kTranslate_Mask | SkMatrix::kScale_Mask) == matrix.getType()); 103 REPORTER_ASSERT(reporter, matrix.rectStaysRect()); 104 105 dst = src; 106 dst.fRight = src.fRight * 2; 107 matrix.setRectToRect(src, dst, SkMatrix::kFill_ScaleToFit); 108 REPORTER_ASSERT(reporter, SkMatrix::kScale_Mask == matrix.getType()); 109 REPORTER_ASSERT(reporter, matrix.rectStaysRect()); 110} 111 112static void test_flatten(skiatest::Reporter* reporter, const SkMatrix& m) { 113 // add 100 in case we have a bug, I don't want to kill my stack in the test 114 char buffer[SkMatrix::kMaxFlattenSize + 100]; 115 uint32_t size1 = m.writeToMemory(NULL); 116 uint32_t size2 = m.writeToMemory(buffer); 117 REPORTER_ASSERT(reporter, size1 == size2); 118 REPORTER_ASSERT(reporter, size1 <= SkMatrix::kMaxFlattenSize); 119 120 SkMatrix m2; 121 uint32_t size3 = m2.readFromMemory(buffer); 122 REPORTER_ASSERT(reporter, size1 == size3); 123 REPORTER_ASSERT(reporter, are_equal(reporter, m, m2)); 124 125 char buffer2[SkMatrix::kMaxFlattenSize + 100]; 126 size3 = m2.writeToMemory(buffer2); 127 REPORTER_ASSERT(reporter, size1 == size3); 128 REPORTER_ASSERT(reporter, memcmp(buffer, buffer2, size1) == 0); 129} 130 131static void test_matrix_max_stretch(skiatest::Reporter* reporter) { 132 SkMatrix identity; 133 identity.reset(); 134 REPORTER_ASSERT(reporter, SK_Scalar1 == identity.getMaxStretch()); 135 136 SkMatrix scale; 137 scale.setScale(SK_Scalar1 * 2, SK_Scalar1 * 4); 138 REPORTER_ASSERT(reporter, SK_Scalar1 * 4 == scale.getMaxStretch()); 139 140 SkMatrix rot90Scale; 141 rot90Scale.setRotate(90 * SK_Scalar1); 142 rot90Scale.postScale(SK_Scalar1 / 4, SK_Scalar1 / 2); 143 REPORTER_ASSERT(reporter, SK_Scalar1 / 2 == rot90Scale.getMaxStretch()); 144 145 SkMatrix rotate; 146 rotate.setRotate(128 * SK_Scalar1); 147 REPORTER_ASSERT(reporter, SkScalarAbs(SK_Scalar1 - rotate.getMaxStretch()) <= SK_ScalarNearlyZero); 148 149 SkMatrix translate; 150 translate.setTranslate(10 * SK_Scalar1, -5 * SK_Scalar1); 151 REPORTER_ASSERT(reporter, SK_Scalar1 == translate.getMaxStretch()); 152 153 SkMatrix perspX; 154 perspX.reset(); 155 perspX.setPerspX(SkScalarToPersp(SK_Scalar1 / 1000)); 156 REPORTER_ASSERT(reporter, -SK_Scalar1 == perspX.getMaxStretch()); 157 158 SkMatrix perspY; 159 perspY.reset(); 160 perspY.setPerspX(SkScalarToPersp(-SK_Scalar1 / 500)); 161 REPORTER_ASSERT(reporter, -SK_Scalar1 == perspY.getMaxStretch()); 162 163 SkMatrix baseMats[] = {scale, rot90Scale, rotate, 164 translate, perspX, perspY}; 165 SkMatrix mats[2*SK_ARRAY_COUNT(baseMats)]; 166 for (size_t i = 0; i < SK_ARRAY_COUNT(baseMats); ++i) { 167 mats[i] = baseMats[i]; 168 bool invertable = mats[i].invert(&mats[i + SK_ARRAY_COUNT(baseMats)]); 169 REPORTER_ASSERT(reporter, invertable); 170 } 171 SkRandom rand; 172 for (int m = 0; m < 1000; ++m) { 173 SkMatrix mat; 174 mat.reset(); 175 for (int i = 0; i < 4; ++i) { 176 int x = rand.nextU() % SK_ARRAY_COUNT(mats); 177 mat.postConcat(mats[x]); 178 } 179 SkScalar stretch = mat.getMaxStretch(); 180 181 if ((stretch < 0) != mat.hasPerspective()) { 182 stretch = mat.getMaxStretch(); 183 } 184 185 REPORTER_ASSERT(reporter, (stretch < 0) == mat.hasPerspective()); 186 187 if (mat.hasPerspective()) { 188 m -= 1; // try another non-persp matrix 189 continue; 190 } 191 192 // test a bunch of vectors. None should be scaled by more than stretch 193 // (modulo some error) and we should find a vector that is scaled by 194 // almost stretch. 195 static const SkScalar gStretchTol = (105 * SK_Scalar1) / 100; 196 static const SkScalar gMaxStretchTol = (97 * SK_Scalar1) / 100; 197 SkScalar max = 0; 198 SkVector vectors[1000]; 199 for (size_t i = 0; i < SK_ARRAY_COUNT(vectors); ++i) { 200 vectors[i].fX = rand.nextSScalar1(); 201 vectors[i].fY = rand.nextSScalar1(); 202 if (!vectors[i].normalize()) { 203 i -= 1; 204 continue; 205 } 206 } 207 mat.mapVectors(vectors, SK_ARRAY_COUNT(vectors)); 208 for (size_t i = 0; i < SK_ARRAY_COUNT(vectors); ++i) { 209 SkScalar d = vectors[i].length(); 210 REPORTER_ASSERT(reporter, SkScalarDiv(d, stretch) < gStretchTol); 211 if (max < d) { 212 max = d; 213 } 214 } 215 REPORTER_ASSERT(reporter, SkScalarDiv(max, stretch) >= gMaxStretchTol); 216 } 217} 218 219static void test_matrix_is_similarity(skiatest::Reporter* reporter) { 220 SkMatrix mat; 221 222 // identity 223 mat.setIdentity(); 224 REPORTER_ASSERT(reporter, mat.isSimilarity()); 225 226 // translation only 227 mat.reset(); 228 mat.setTranslate(SkIntToScalar(100), SkIntToScalar(100)); 229 REPORTER_ASSERT(reporter, mat.isSimilarity()); 230 231 // scale with same size 232 mat.reset(); 233 mat.setScale(SkIntToScalar(15), SkIntToScalar(15)); 234 REPORTER_ASSERT(reporter, mat.isSimilarity()); 235 236 // scale with one negative 237 mat.reset(); 238 mat.setScale(SkIntToScalar(-15), SkIntToScalar(15)); 239 REPORTER_ASSERT(reporter, mat.isSimilarity()); 240 241 // scale with different size 242 mat.reset(); 243 mat.setScale(SkIntToScalar(15), SkIntToScalar(20)); 244 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 245 246 // scale with same size at a pivot point 247 mat.reset(); 248 mat.setScale(SkIntToScalar(15), SkIntToScalar(15), 249 SkIntToScalar(2), SkIntToScalar(2)); 250 REPORTER_ASSERT(reporter, mat.isSimilarity()); 251 252 // scale with different size at a pivot point 253 mat.reset(); 254 mat.setScale(SkIntToScalar(15), SkIntToScalar(20), 255 SkIntToScalar(2), SkIntToScalar(2)); 256 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 257 258 // skew with same size 259 mat.reset(); 260 mat.setSkew(SkIntToScalar(15), SkIntToScalar(15)); 261 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 262 263 // skew with different size 264 mat.reset(); 265 mat.setSkew(SkIntToScalar(15), SkIntToScalar(20)); 266 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 267 268 // skew with same size at a pivot point 269 mat.reset(); 270 mat.setSkew(SkIntToScalar(15), SkIntToScalar(15), 271 SkIntToScalar(2), SkIntToScalar(2)); 272 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 273 274 // skew with different size at a pivot point 275 mat.reset(); 276 mat.setSkew(SkIntToScalar(15), SkIntToScalar(20), 277 SkIntToScalar(2), SkIntToScalar(2)); 278 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 279 280 // perspective x 281 mat.reset(); 282 mat.setPerspX(SkScalarToPersp(SK_Scalar1 / 2)); 283 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 284 285 // perspective y 286 mat.reset(); 287 mat.setPerspY(SkScalarToPersp(SK_Scalar1 / 2)); 288 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 289 290#if SK_SCALAR_IS_FLOAT 291 /* We bypass the following tests for SK_SCALAR_IS_FIXED build. 292 * The long discussion can be found in this issue: 293 * http://codereview.appspot.com/5999050/ 294 * In short, we haven't found a perfect way to fix the precision 295 * issue, i.e. the way we use tolerance in isSimilarityTransformation 296 * is incorrect. The situation becomes worse in fixed build, so 297 * we disabled rotation related tests for fixed build. 298 */ 299 300 // rotate 301 for (int angle = 0; angle < 360; ++angle) { 302 mat.reset(); 303 mat.setRotate(SkIntToScalar(angle)); 304 REPORTER_ASSERT(reporter, mat.isSimilarity()); 305 } 306 307 // see if there are any accumulated precision issues 308 mat.reset(); 309 for (int i = 1; i < 360; i++) { 310 mat.postRotate(SkIntToScalar(1)); 311 } 312 REPORTER_ASSERT(reporter, mat.isSimilarity()); 313 314 // rotate + translate 315 mat.reset(); 316 mat.setRotate(SkIntToScalar(30)); 317 mat.postTranslate(SkIntToScalar(10), SkIntToScalar(20)); 318 REPORTER_ASSERT(reporter, mat.isSimilarity()); 319 320 // rotate + uniform scale 321 mat.reset(); 322 mat.setRotate(SkIntToScalar(30)); 323 mat.postScale(SkIntToScalar(2), SkIntToScalar(2)); 324 REPORTER_ASSERT(reporter, mat.isSimilarity()); 325 326 // rotate + non-uniform scale 327 mat.reset(); 328 mat.setRotate(SkIntToScalar(30)); 329 mat.postScale(SkIntToScalar(3), SkIntToScalar(2)); 330 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 331#endif 332 333 // all zero 334 mat.setAll(0, 0, 0, 0, 0, 0, 0, 0, 0); 335 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 336 337 // all zero except perspective 338 mat.setAll(0, 0, 0, 0, 0, 0, 0, 0, SK_Scalar1); 339 REPORTER_ASSERT(reporter, !mat.isSimilarity()); 340 341 // scales zero, only skews 342 mat.setAll(0, SK_Scalar1, 0, 343 SK_Scalar1, 0, 0, 344 0, 0, SkMatrix::I()[8]); 345 REPORTER_ASSERT(reporter, mat.isSimilarity()); 346} 347 348static void TestMatrix(skiatest::Reporter* reporter) { 349 SkMatrix mat, inverse, iden1, iden2; 350 351 mat.reset(); 352 mat.setTranslate(SK_Scalar1, SK_Scalar1); 353 REPORTER_ASSERT(reporter, mat.invert(&inverse)); 354 iden1.setConcat(mat, inverse); 355 REPORTER_ASSERT(reporter, is_identity(iden1)); 356 357 mat.setScale(SkIntToScalar(2), SkIntToScalar(4)); 358 REPORTER_ASSERT(reporter, mat.invert(&inverse)); 359 iden1.setConcat(mat, inverse); 360 REPORTER_ASSERT(reporter, is_identity(iden1)); 361 test_flatten(reporter, mat); 362 363 mat.setScale(SK_Scalar1/2, SkIntToScalar(2)); 364 REPORTER_ASSERT(reporter, mat.invert(&inverse)); 365 iden1.setConcat(mat, inverse); 366 REPORTER_ASSERT(reporter, is_identity(iden1)); 367 test_flatten(reporter, mat); 368 369 mat.setScale(SkIntToScalar(3), SkIntToScalar(5), SkIntToScalar(20), 0); 370 mat.postRotate(SkIntToScalar(25)); 371 REPORTER_ASSERT(reporter, mat.invert(NULL)); 372 REPORTER_ASSERT(reporter, mat.invert(&inverse)); 373 iden1.setConcat(mat, inverse); 374 REPORTER_ASSERT(reporter, is_identity(iden1)); 375 iden2.setConcat(inverse, mat); 376 REPORTER_ASSERT(reporter, is_identity(iden2)); 377 test_flatten(reporter, mat); 378 test_flatten(reporter, iden2); 379 380 mat.setScale(0, SK_Scalar1); 381 REPORTER_ASSERT(reporter, !mat.invert(NULL)); 382 REPORTER_ASSERT(reporter, !mat.invert(&inverse)); 383 mat.setScale(SK_Scalar1, 0); 384 REPORTER_ASSERT(reporter, !mat.invert(NULL)); 385 REPORTER_ASSERT(reporter, !mat.invert(&inverse)); 386 387 // rectStaysRect test 388 { 389 static const struct { 390 SkScalar m00, m01, m10, m11; 391 bool mStaysRect; 392 } 393 gRectStaysRectSamples[] = { 394 { 0, 0, 0, 0, false }, 395 { 0, 0, 0, SK_Scalar1, false }, 396 { 0, 0, SK_Scalar1, 0, false }, 397 { 0, 0, SK_Scalar1, SK_Scalar1, false }, 398 { 0, SK_Scalar1, 0, 0, false }, 399 { 0, SK_Scalar1, 0, SK_Scalar1, false }, 400 { 0, SK_Scalar1, SK_Scalar1, 0, true }, 401 { 0, SK_Scalar1, SK_Scalar1, SK_Scalar1, false }, 402 { SK_Scalar1, 0, 0, 0, false }, 403 { SK_Scalar1, 0, 0, SK_Scalar1, true }, 404 { SK_Scalar1, 0, SK_Scalar1, 0, false }, 405 { SK_Scalar1, 0, SK_Scalar1, SK_Scalar1, false }, 406 { SK_Scalar1, SK_Scalar1, 0, 0, false }, 407 { SK_Scalar1, SK_Scalar1, 0, SK_Scalar1, false }, 408 { SK_Scalar1, SK_Scalar1, SK_Scalar1, 0, false }, 409 { SK_Scalar1, SK_Scalar1, SK_Scalar1, SK_Scalar1, false } 410 }; 411 412 for (size_t i = 0; i < SK_ARRAY_COUNT(gRectStaysRectSamples); i++) { 413 SkMatrix m; 414 415 m.reset(); 416 m.set(SkMatrix::kMScaleX, gRectStaysRectSamples[i].m00); 417 m.set(SkMatrix::kMSkewX, gRectStaysRectSamples[i].m01); 418 m.set(SkMatrix::kMSkewY, gRectStaysRectSamples[i].m10); 419 m.set(SkMatrix::kMScaleY, gRectStaysRectSamples[i].m11); 420 REPORTER_ASSERT(reporter, 421 m.rectStaysRect() == gRectStaysRectSamples[i].mStaysRect); 422 } 423 } 424 425 mat.reset(); 426 mat.set(SkMatrix::kMScaleX, SkIntToScalar(1)); 427 mat.set(SkMatrix::kMSkewX, SkIntToScalar(2)); 428 mat.set(SkMatrix::kMTransX, SkIntToScalar(3)); 429 mat.set(SkMatrix::kMSkewY, SkIntToScalar(4)); 430 mat.set(SkMatrix::kMScaleY, SkIntToScalar(5)); 431 mat.set(SkMatrix::kMTransY, SkIntToScalar(6)); 432 SkScalar affine[6]; 433 REPORTER_ASSERT(reporter, mat.asAffine(affine)); 434 435 #define affineEqual(e) affine[SkMatrix::kA##e] == mat.get(SkMatrix::kM##e) 436 REPORTER_ASSERT(reporter, affineEqual(ScaleX)); 437 REPORTER_ASSERT(reporter, affineEqual(SkewY)); 438 REPORTER_ASSERT(reporter, affineEqual(SkewX)); 439 REPORTER_ASSERT(reporter, affineEqual(ScaleY)); 440 REPORTER_ASSERT(reporter, affineEqual(TransX)); 441 REPORTER_ASSERT(reporter, affineEqual(TransY)); 442 #undef affineEqual 443 444 mat.set(SkMatrix::kMPersp1, SkScalarToPersp(SK_Scalar1 / 2)); 445 REPORTER_ASSERT(reporter, !mat.asAffine(affine)); 446 447 SkMatrix mat2; 448 mat2.reset(); 449 mat.reset(); 450 SkScalar zero = 0; 451 mat.set(SkMatrix::kMSkewX, -zero); 452 REPORTER_ASSERT(reporter, are_equal(reporter, mat, mat2)); 453 454 mat2.reset(); 455 mat.reset(); 456 mat.set(SkMatrix::kMSkewX, SK_ScalarNaN); 457 mat2.set(SkMatrix::kMSkewX, SK_ScalarNaN); 458 // fixed pt doesn't have the property that NaN does not equal itself. 459#ifdef SK_SCALAR_IS_FIXED 460 REPORTER_ASSERT(reporter, are_equal(reporter, mat, mat2)); 461#else 462 REPORTER_ASSERT(reporter, !are_equal(reporter, mat, mat2)); 463#endif 464 465 test_matrix_max_stretch(reporter); 466 test_matrix_is_similarity(reporter); 467 test_matrix_recttorect(reporter); 468} 469 470#include "TestClassDef.h" 471DEFINE_TESTCLASS("Matrix", MatrixTestClass, TestMatrix) 472