reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 1 | /* libs/corecg/SkMatrix.cpp |
| 2 | ** |
| 3 | ** Copyright 2006, The Android Open Source Project |
| 4 | ** |
| 5 | ** Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | ** you may not use this file except in compliance with the License. |
| 7 | ** You may obtain a copy of the License at |
| 8 | ** |
| 9 | ** http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | ** |
| 11 | ** Unless required by applicable law or agreed to in writing, software |
| 12 | ** distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | ** See the License for the specific language governing permissions and |
| 15 | ** limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | #include "SkMatrix.h" |
| 19 | #include "Sk64.h" |
| 20 | #include "SkFloatBits.h" |
reed@android.com | 3174558 | 2009-07-08 14:46:11 +0000 | [diff] [blame] | 21 | #include "SkScalarCompare.h" |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 22 | #include "SkString.h" |
| 23 | |
| 24 | #ifdef SK_SCALAR_IS_FLOAT |
| 25 | #define kMatrix22Elem SK_Scalar1 |
reed@android.com | ab7ac02 | 2009-09-18 13:38:43 +0000 | [diff] [blame] | 26 | |
| 27 | static inline float SkDoubleToFloat(double x) { |
| 28 | return static_cast<float>(x); |
| 29 | } |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 30 | #else |
| 31 | #define kMatrix22Elem SK_Fract1 |
| 32 | #endif |
| 33 | |
| 34 | /* [scale-x skew-x trans-x] [X] [X'] |
| 35 | [skew-y scale-y trans-y] * [Y] = [Y'] |
| 36 | [persp-0 persp-1 persp-2] [1] [1 ] |
| 37 | */ |
| 38 | |
| 39 | void SkMatrix::reset() { |
| 40 | fMat[kMScaleX] = fMat[kMScaleY] = SK_Scalar1; |
| 41 | fMat[kMSkewX] = fMat[kMSkewY] = |
| 42 | fMat[kMTransX] = fMat[kMTransY] = |
| 43 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 44 | fMat[kMPersp2] = kMatrix22Elem; |
| 45 | |
| 46 | this->setTypeMask(kIdentity_Mask | kRectStaysRect_Mask); |
| 47 | } |
| 48 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 49 | // this guy aligns with the masks, so we can compute a mask from a varaible 0/1 |
| 50 | enum { |
| 51 | kTranslate_Shift, |
| 52 | kScale_Shift, |
| 53 | kAffine_Shift, |
| 54 | kPerspective_Shift, |
| 55 | kRectStaysRect_Shift |
| 56 | }; |
| 57 | |
| 58 | #ifdef SK_SCALAR_IS_FLOAT |
| 59 | static const int32_t kScalar1Int = 0x3f800000; |
| 60 | static const int32_t kPersp1Int = 0x3f800000; |
| 61 | #else |
| 62 | #define scalarAsInt(x) (x) |
| 63 | static const int32_t kScalar1Int = (1 << 16); |
| 64 | static const int32_t kPersp1Int = (1 << 30); |
| 65 | #endif |
| 66 | |
| 67 | uint8_t SkMatrix::computeTypeMask() const { |
| 68 | unsigned mask = 0; |
| 69 | |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 70 | #ifdef SK_SCALAR_SLOW_COMPARES |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 71 | if (SkScalarAs2sCompliment(fMat[kMPersp0]) | |
| 72 | SkScalarAs2sCompliment(fMat[kMPersp1]) | |
| 73 | (SkScalarAs2sCompliment(fMat[kMPersp2]) - kPersp1Int)) { |
| 74 | mask |= kPerspective_Mask; |
| 75 | } |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 76 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 77 | if (SkScalarAs2sCompliment(fMat[kMTransX]) | |
| 78 | SkScalarAs2sCompliment(fMat[kMTransY])) { |
| 79 | mask |= kTranslate_Mask; |
| 80 | } |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 81 | #else |
| 82 | // Benchmarking suggests that replacing this set of SkScalarAs2sCompliment |
| 83 | // is a win, but replacing those below is not. We don't yet understand |
| 84 | // that result. |
| 85 | if (fMat[kMPersp0] != 0 || fMat[kMPersp1] != 0 || |
tomhudson@google.com | 521ed7c | 2011-06-06 17:21:44 +0000 | [diff] [blame] | 86 | fMat[kMPersp2] != kMatrix22Elem) { |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 87 | mask |= kPerspective_Mask; |
| 88 | } |
| 89 | |
| 90 | if (fMat[kMTransX] != 0 || fMat[kMTransY] != 0) { |
| 91 | mask |= kTranslate_Mask; |
| 92 | } |
| 93 | #endif |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 94 | |
| 95 | int m00 = SkScalarAs2sCompliment(fMat[SkMatrix::kMScaleX]); |
| 96 | int m01 = SkScalarAs2sCompliment(fMat[SkMatrix::kMSkewX]); |
| 97 | int m10 = SkScalarAs2sCompliment(fMat[SkMatrix::kMSkewY]); |
| 98 | int m11 = SkScalarAs2sCompliment(fMat[SkMatrix::kMScaleY]); |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 99 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 100 | if (m01 | m10) { |
| 101 | mask |= kAffine_Mask; |
| 102 | } |
| 103 | |
| 104 | if ((m00 - kScalar1Int) | (m11 - kScalar1Int)) { |
| 105 | mask |= kScale_Mask; |
| 106 | } |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 107 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 108 | if ((mask & kPerspective_Mask) == 0) { |
| 109 | // map non-zero to 1 |
| 110 | m00 = m00 != 0; |
| 111 | m01 = m01 != 0; |
| 112 | m10 = m10 != 0; |
| 113 | m11 = m11 != 0; |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 114 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 115 | // record if the (p)rimary and (s)econdary diagonals are all 0 or |
| 116 | // all non-zero (answer is 0 or 1) |
| 117 | int dp0 = (m00 | m11) ^ 1; // true if both are 0 |
| 118 | int dp1 = m00 & m11; // true if both are 1 |
| 119 | int ds0 = (m01 | m10) ^ 1; // true if both are 0 |
| 120 | int ds1 = m01 & m10; // true if both are 1 |
tomhudson@google.com | ac38525 | 2011-06-06 15:18:28 +0000 | [diff] [blame] | 121 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 122 | // return 1 if primary is 1 and secondary is 0 or |
| 123 | // primary is 0 and secondary is 1 |
| 124 | mask |= ((dp0 & ds1) | (dp1 & ds0)) << kRectStaysRect_Shift; |
| 125 | } |
| 126 | |
| 127 | return SkToU8(mask); |
| 128 | } |
| 129 | |
| 130 | /////////////////////////////////////////////////////////////////////////////// |
| 131 | |
reed@google.com | 3fb5187 | 2011-06-01 15:11:22 +0000 | [diff] [blame] | 132 | #ifdef SK_SCALAR_IS_FLOAT |
| 133 | |
| 134 | bool operator==(const SkMatrix& a, const SkMatrix& b) { |
| 135 | const SkScalar* SK_RESTRICT ma = a.fMat; |
| 136 | const SkScalar* SK_RESTRICT mb = b.fMat; |
| 137 | |
| 138 | return ma[0] == mb[0] && ma[1] == mb[1] && ma[2] == mb[2] && |
| 139 | ma[3] == mb[3] && ma[4] == mb[4] && ma[5] == mb[5] && |
| 140 | ma[6] == mb[6] && ma[7] == mb[7] && ma[8] == mb[8]; |
| 141 | } |
| 142 | |
| 143 | #endif |
| 144 | |
| 145 | /////////////////////////////////////////////////////////////////////////////// |
| 146 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 147 | void SkMatrix::setTranslate(SkScalar dx, SkScalar dy) { |
reed@android.com | 3174558 | 2009-07-08 14:46:11 +0000 | [diff] [blame] | 148 | if (SkScalarToCompareType(dx) || SkScalarToCompareType(dy)) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 149 | fMat[kMTransX] = dx; |
| 150 | fMat[kMTransY] = dy; |
| 151 | |
| 152 | fMat[kMScaleX] = fMat[kMScaleY] = SK_Scalar1; |
| 153 | fMat[kMSkewX] = fMat[kMSkewY] = |
| 154 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 155 | fMat[kMPersp2] = kMatrix22Elem; |
| 156 | |
| 157 | this->setTypeMask(kTranslate_Mask | kRectStaysRect_Mask); |
| 158 | } else { |
| 159 | this->reset(); |
| 160 | } |
| 161 | } |
| 162 | |
| 163 | bool SkMatrix::preTranslate(SkScalar dx, SkScalar dy) { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 164 | if (this->hasPerspective()) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 165 | SkMatrix m; |
| 166 | m.setTranslate(dx, dy); |
| 167 | return this->preConcat(m); |
| 168 | } |
| 169 | |
reed@android.com | 3174558 | 2009-07-08 14:46:11 +0000 | [diff] [blame] | 170 | if (SkScalarToCompareType(dx) || SkScalarToCompareType(dy)) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 171 | fMat[kMTransX] += SkScalarMul(fMat[kMScaleX], dx) + |
| 172 | SkScalarMul(fMat[kMSkewX], dy); |
| 173 | fMat[kMTransY] += SkScalarMul(fMat[kMSkewY], dx) + |
| 174 | SkScalarMul(fMat[kMScaleY], dy); |
| 175 | |
| 176 | this->setTypeMask(kUnknown_Mask); |
| 177 | } |
| 178 | return true; |
| 179 | } |
| 180 | |
| 181 | bool SkMatrix::postTranslate(SkScalar dx, SkScalar dy) { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 182 | if (this->hasPerspective()) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 183 | SkMatrix m; |
| 184 | m.setTranslate(dx, dy); |
| 185 | return this->postConcat(m); |
| 186 | } |
| 187 | |
reed@android.com | 3174558 | 2009-07-08 14:46:11 +0000 | [diff] [blame] | 188 | if (SkScalarToCompareType(dx) || SkScalarToCompareType(dy)) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 189 | fMat[kMTransX] += dx; |
| 190 | fMat[kMTransY] += dy; |
| 191 | this->setTypeMask(kUnknown_Mask); |
| 192 | } |
| 193 | return true; |
| 194 | } |
| 195 | |
| 196 | /////////////////////////////////////////////////////////////////////////////// |
| 197 | |
| 198 | void SkMatrix::setScale(SkScalar sx, SkScalar sy, SkScalar px, SkScalar py) { |
| 199 | fMat[kMScaleX] = sx; |
| 200 | fMat[kMScaleY] = sy; |
| 201 | fMat[kMTransX] = px - SkScalarMul(sx, px); |
| 202 | fMat[kMTransY] = py - SkScalarMul(sy, py); |
| 203 | fMat[kMPersp2] = kMatrix22Elem; |
| 204 | |
| 205 | fMat[kMSkewX] = fMat[kMSkewY] = |
| 206 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 207 | |
| 208 | this->setTypeMask(kScale_Mask | kTranslate_Mask | kRectStaysRect_Mask); |
| 209 | } |
| 210 | |
| 211 | void SkMatrix::setScale(SkScalar sx, SkScalar sy) { |
| 212 | fMat[kMScaleX] = sx; |
| 213 | fMat[kMScaleY] = sy; |
| 214 | fMat[kMPersp2] = kMatrix22Elem; |
| 215 | |
| 216 | fMat[kMTransX] = fMat[kMTransY] = |
| 217 | fMat[kMSkewX] = fMat[kMSkewY] = |
| 218 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 219 | |
| 220 | this->setTypeMask(kScale_Mask | kRectStaysRect_Mask); |
| 221 | } |
| 222 | |
| 223 | bool SkMatrix::preScale(SkScalar sx, SkScalar sy, SkScalar px, SkScalar py) { |
| 224 | SkMatrix m; |
| 225 | m.setScale(sx, sy, px, py); |
| 226 | return this->preConcat(m); |
| 227 | } |
| 228 | |
| 229 | bool SkMatrix::preScale(SkScalar sx, SkScalar sy) { |
reed@google.com | 3fb5187 | 2011-06-01 15:11:22 +0000 | [diff] [blame] | 230 | #ifdef SK_SCALAR_IS_FIXED |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 231 | SkMatrix m; |
| 232 | m.setScale(sx, sy); |
| 233 | return this->preConcat(m); |
reed@google.com | 3fb5187 | 2011-06-01 15:11:22 +0000 | [diff] [blame] | 234 | #else |
| 235 | // the assumption is that these multiplies are very cheap, and that |
| 236 | // a full concat and/or just computing the matrix type is more expensive. |
| 237 | // Also, the fixed-point case checks for overflow, but the float doesn't, |
| 238 | // so we can get away with these blind multiplies. |
| 239 | |
| 240 | fMat[kMScaleX] = SkScalarMul(fMat[kMScaleX], sx); |
| 241 | fMat[kMSkewY] = SkScalarMul(fMat[kMSkewY], sx); |
| 242 | fMat[kMPersp0] = SkScalarMul(fMat[kMPersp0], sx); |
| 243 | |
| 244 | fMat[kMSkewX] = SkScalarMul(fMat[kMSkewX], sy); |
| 245 | fMat[kMScaleY] = SkScalarMul(fMat[kMScaleY], sy); |
| 246 | fMat[kMPersp1] = SkScalarMul(fMat[kMPersp1], sy); |
| 247 | |
| 248 | this->orTypeMask(kScale_Mask); |
| 249 | return true; |
| 250 | #endif |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 251 | } |
| 252 | |
| 253 | bool SkMatrix::postScale(SkScalar sx, SkScalar sy, SkScalar px, SkScalar py) { |
| 254 | SkMatrix m; |
| 255 | m.setScale(sx, sy, px, py); |
| 256 | return this->postConcat(m); |
| 257 | } |
| 258 | |
| 259 | bool SkMatrix::postScale(SkScalar sx, SkScalar sy) { |
| 260 | SkMatrix m; |
| 261 | m.setScale(sx, sy); |
| 262 | return this->postConcat(m); |
| 263 | } |
| 264 | |
| 265 | #ifdef SK_SCALAR_IS_FIXED |
| 266 | static inline SkFixed roundidiv(SkFixed numer, int denom) { |
| 267 | int ns = numer >> 31; |
| 268 | int ds = denom >> 31; |
| 269 | numer = (numer ^ ns) - ns; |
| 270 | denom = (denom ^ ds) - ds; |
| 271 | |
| 272 | SkFixed answer = (numer + (denom >> 1)) / denom; |
| 273 | int as = ns ^ ds; |
| 274 | return (answer ^ as) - as; |
| 275 | } |
| 276 | #endif |
| 277 | |
| 278 | // this guy perhaps can go away, if we have a fract/high-precision way to |
| 279 | // scale matrices |
| 280 | bool SkMatrix::postIDiv(int divx, int divy) { |
| 281 | if (divx == 0 || divy == 0) { |
| 282 | return false; |
| 283 | } |
| 284 | |
| 285 | #ifdef SK_SCALAR_IS_FIXED |
| 286 | fMat[kMScaleX] = roundidiv(fMat[kMScaleX], divx); |
| 287 | fMat[kMSkewX] = roundidiv(fMat[kMSkewX], divx); |
| 288 | fMat[kMTransX] = roundidiv(fMat[kMTransX], divx); |
| 289 | |
| 290 | fMat[kMScaleY] = roundidiv(fMat[kMScaleY], divy); |
| 291 | fMat[kMSkewY] = roundidiv(fMat[kMSkewY], divy); |
| 292 | fMat[kMTransY] = roundidiv(fMat[kMTransY], divy); |
| 293 | #else |
| 294 | const float invX = 1.f / divx; |
| 295 | const float invY = 1.f / divy; |
| 296 | |
| 297 | fMat[kMScaleX] *= invX; |
| 298 | fMat[kMSkewX] *= invX; |
| 299 | fMat[kMTransX] *= invX; |
| 300 | |
| 301 | fMat[kMScaleY] *= invY; |
| 302 | fMat[kMSkewY] *= invY; |
| 303 | fMat[kMTransY] *= invY; |
| 304 | #endif |
| 305 | |
| 306 | this->setTypeMask(kUnknown_Mask); |
| 307 | return true; |
| 308 | } |
| 309 | |
| 310 | //////////////////////////////////////////////////////////////////////////////////// |
| 311 | |
| 312 | void SkMatrix::setSinCos(SkScalar sinV, SkScalar cosV, |
| 313 | SkScalar px, SkScalar py) { |
| 314 | const SkScalar oneMinusCosV = SK_Scalar1 - cosV; |
| 315 | |
| 316 | fMat[kMScaleX] = cosV; |
| 317 | fMat[kMSkewX] = -sinV; |
| 318 | fMat[kMTransX] = SkScalarMul(sinV, py) + SkScalarMul(oneMinusCosV, px); |
| 319 | |
| 320 | fMat[kMSkewY] = sinV; |
| 321 | fMat[kMScaleY] = cosV; |
| 322 | fMat[kMTransY] = SkScalarMul(-sinV, px) + SkScalarMul(oneMinusCosV, py); |
| 323 | |
| 324 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 325 | fMat[kMPersp2] = kMatrix22Elem; |
| 326 | |
| 327 | this->setTypeMask(kUnknown_Mask); |
| 328 | } |
| 329 | |
| 330 | void SkMatrix::setSinCos(SkScalar sinV, SkScalar cosV) { |
| 331 | fMat[kMScaleX] = cosV; |
| 332 | fMat[kMSkewX] = -sinV; |
| 333 | fMat[kMTransX] = 0; |
| 334 | |
| 335 | fMat[kMSkewY] = sinV; |
| 336 | fMat[kMScaleY] = cosV; |
| 337 | fMat[kMTransY] = 0; |
| 338 | |
| 339 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 340 | fMat[kMPersp2] = kMatrix22Elem; |
| 341 | |
| 342 | this->setTypeMask(kUnknown_Mask); |
| 343 | } |
| 344 | |
| 345 | void SkMatrix::setRotate(SkScalar degrees, SkScalar px, SkScalar py) { |
| 346 | SkScalar sinV, cosV; |
| 347 | sinV = SkScalarSinCos(SkDegreesToRadians(degrees), &cosV); |
| 348 | this->setSinCos(sinV, cosV, px, py); |
| 349 | } |
| 350 | |
| 351 | void SkMatrix::setRotate(SkScalar degrees) { |
| 352 | SkScalar sinV, cosV; |
| 353 | sinV = SkScalarSinCos(SkDegreesToRadians(degrees), &cosV); |
| 354 | this->setSinCos(sinV, cosV); |
| 355 | } |
| 356 | |
| 357 | bool SkMatrix::preRotate(SkScalar degrees, SkScalar px, SkScalar py) { |
| 358 | SkMatrix m; |
| 359 | m.setRotate(degrees, px, py); |
| 360 | return this->preConcat(m); |
| 361 | } |
| 362 | |
| 363 | bool SkMatrix::preRotate(SkScalar degrees) { |
| 364 | SkMatrix m; |
| 365 | m.setRotate(degrees); |
| 366 | return this->preConcat(m); |
| 367 | } |
| 368 | |
| 369 | bool SkMatrix::postRotate(SkScalar degrees, SkScalar px, SkScalar py) { |
| 370 | SkMatrix m; |
| 371 | m.setRotate(degrees, px, py); |
| 372 | return this->postConcat(m); |
| 373 | } |
| 374 | |
| 375 | bool SkMatrix::postRotate(SkScalar degrees) { |
| 376 | SkMatrix m; |
| 377 | m.setRotate(degrees); |
| 378 | return this->postConcat(m); |
| 379 | } |
| 380 | |
| 381 | //////////////////////////////////////////////////////////////////////////////////// |
| 382 | |
| 383 | void SkMatrix::setSkew(SkScalar sx, SkScalar sy, SkScalar px, SkScalar py) { |
| 384 | fMat[kMScaleX] = SK_Scalar1; |
| 385 | fMat[kMSkewX] = sx; |
| 386 | fMat[kMTransX] = SkScalarMul(-sx, py); |
| 387 | |
| 388 | fMat[kMSkewY] = sy; |
| 389 | fMat[kMScaleY] = SK_Scalar1; |
| 390 | fMat[kMTransY] = SkScalarMul(-sy, px); |
| 391 | |
| 392 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 393 | fMat[kMPersp2] = kMatrix22Elem; |
| 394 | |
| 395 | this->setTypeMask(kUnknown_Mask); |
| 396 | } |
| 397 | |
| 398 | void SkMatrix::setSkew(SkScalar sx, SkScalar sy) { |
| 399 | fMat[kMScaleX] = SK_Scalar1; |
| 400 | fMat[kMSkewX] = sx; |
| 401 | fMat[kMTransX] = 0; |
| 402 | |
| 403 | fMat[kMSkewY] = sy; |
| 404 | fMat[kMScaleY] = SK_Scalar1; |
| 405 | fMat[kMTransY] = 0; |
| 406 | |
| 407 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 408 | fMat[kMPersp2] = kMatrix22Elem; |
| 409 | |
| 410 | this->setTypeMask(kUnknown_Mask); |
| 411 | } |
| 412 | |
| 413 | bool SkMatrix::preSkew(SkScalar sx, SkScalar sy, SkScalar px, SkScalar py) { |
| 414 | SkMatrix m; |
| 415 | m.setSkew(sx, sy, px, py); |
| 416 | return this->preConcat(m); |
| 417 | } |
| 418 | |
| 419 | bool SkMatrix::preSkew(SkScalar sx, SkScalar sy) { |
| 420 | SkMatrix m; |
| 421 | m.setSkew(sx, sy); |
| 422 | return this->preConcat(m); |
| 423 | } |
| 424 | |
| 425 | bool SkMatrix::postSkew(SkScalar sx, SkScalar sy, SkScalar px, SkScalar py) { |
| 426 | SkMatrix m; |
| 427 | m.setSkew(sx, sy, px, py); |
| 428 | return this->postConcat(m); |
| 429 | } |
| 430 | |
| 431 | bool SkMatrix::postSkew(SkScalar sx, SkScalar sy) { |
| 432 | SkMatrix m; |
| 433 | m.setSkew(sx, sy); |
| 434 | return this->postConcat(m); |
| 435 | } |
| 436 | |
| 437 | /////////////////////////////////////////////////////////////////////////////// |
| 438 | |
| 439 | bool SkMatrix::setRectToRect(const SkRect& src, const SkRect& dst, |
| 440 | ScaleToFit align) |
| 441 | { |
| 442 | if (src.isEmpty()) { |
| 443 | this->reset(); |
| 444 | return false; |
| 445 | } |
| 446 | |
| 447 | if (dst.isEmpty()) { |
reed@android.com | 4516f47 | 2009-06-29 16:25:36 +0000 | [diff] [blame] | 448 | sk_bzero(fMat, 8 * sizeof(SkScalar)); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 449 | this->setTypeMask(kScale_Mask | kRectStaysRect_Mask); |
| 450 | } else { |
| 451 | SkScalar tx, sx = SkScalarDiv(dst.width(), src.width()); |
| 452 | SkScalar ty, sy = SkScalarDiv(dst.height(), src.height()); |
| 453 | bool xLarger = false; |
| 454 | |
| 455 | if (align != kFill_ScaleToFit) { |
| 456 | if (sx > sy) { |
| 457 | xLarger = true; |
| 458 | sx = sy; |
| 459 | } else { |
| 460 | sy = sx; |
| 461 | } |
| 462 | } |
| 463 | |
| 464 | tx = dst.fLeft - SkScalarMul(src.fLeft, sx); |
| 465 | ty = dst.fTop - SkScalarMul(src.fTop, sy); |
| 466 | if (align == kCenter_ScaleToFit || align == kEnd_ScaleToFit) { |
| 467 | SkScalar diff; |
| 468 | |
| 469 | if (xLarger) { |
| 470 | diff = dst.width() - SkScalarMul(src.width(), sy); |
| 471 | } else { |
| 472 | diff = dst.height() - SkScalarMul(src.height(), sy); |
| 473 | } |
| 474 | |
| 475 | if (align == kCenter_ScaleToFit) { |
| 476 | diff = SkScalarHalf(diff); |
| 477 | } |
| 478 | |
| 479 | if (xLarger) { |
| 480 | tx += diff; |
| 481 | } else { |
| 482 | ty += diff; |
| 483 | } |
| 484 | } |
| 485 | |
| 486 | fMat[kMScaleX] = sx; |
| 487 | fMat[kMScaleY] = sy; |
| 488 | fMat[kMTransX] = tx; |
| 489 | fMat[kMTransY] = ty; |
| 490 | fMat[kMSkewX] = fMat[kMSkewY] = |
| 491 | fMat[kMPersp0] = fMat[kMPersp1] = 0; |
| 492 | |
| 493 | this->setTypeMask(kScale_Mask | kTranslate_Mask | kRectStaysRect_Mask); |
| 494 | } |
| 495 | // shared cleanup |
| 496 | fMat[kMPersp2] = kMatrix22Elem; |
| 497 | return true; |
| 498 | } |
| 499 | |
| 500 | /////////////////////////////////////////////////////////////////////////////// |
| 501 | |
| 502 | #ifdef SK_SCALAR_IS_FLOAT |
| 503 | static inline int fixmuladdmul(float a, float b, float c, float d, |
| 504 | float* result) { |
reed@android.com | ab7ac02 | 2009-09-18 13:38:43 +0000 | [diff] [blame] | 505 | *result = SkDoubleToFloat((double)a * b + (double)c * d); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 506 | return true; |
| 507 | } |
| 508 | |
| 509 | static inline bool rowcol3(const float row[], const float col[], |
| 510 | float* result) { |
| 511 | *result = row[0] * col[0] + row[1] * col[3] + row[2] * col[6]; |
| 512 | return true; |
| 513 | } |
| 514 | |
| 515 | static inline int negifaddoverflows(float& result, float a, float b) { |
| 516 | result = a + b; |
| 517 | return 0; |
| 518 | } |
| 519 | #else |
| 520 | static inline bool fixmuladdmul(SkFixed a, SkFixed b, SkFixed c, SkFixed d, |
| 521 | SkFixed* result) { |
| 522 | Sk64 tmp1, tmp2; |
| 523 | tmp1.setMul(a, b); |
| 524 | tmp2.setMul(c, d); |
| 525 | tmp1.add(tmp2); |
| 526 | if (tmp1.isFixed()) { |
| 527 | *result = tmp1.getFixed(); |
| 528 | return true; |
| 529 | } |
| 530 | return false; |
| 531 | } |
| 532 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 533 | static inline SkFixed fracmuladdmul(SkFixed a, SkFract b, SkFixed c, |
| 534 | SkFract d) { |
| 535 | Sk64 tmp1, tmp2; |
| 536 | tmp1.setMul(a, b); |
| 537 | tmp2.setMul(c, d); |
| 538 | tmp1.add(tmp2); |
| 539 | return tmp1.getFract(); |
| 540 | } |
| 541 | |
| 542 | static inline bool rowcol3(const SkFixed row[], const SkFixed col[], |
| 543 | SkFixed* result) { |
| 544 | Sk64 tmp1, tmp2; |
| 545 | |
| 546 | tmp1.setMul(row[0], col[0]); // N * fixed |
| 547 | tmp2.setMul(row[1], col[3]); // N * fixed |
| 548 | tmp1.add(tmp2); |
| 549 | |
| 550 | tmp2.setMul(row[2], col[6]); // N * fract |
| 551 | tmp2.roundRight(14); // make it fixed |
| 552 | tmp1.add(tmp2); |
| 553 | |
| 554 | if (tmp1.isFixed()) { |
| 555 | *result = tmp1.getFixed(); |
| 556 | return true; |
| 557 | } |
| 558 | return false; |
| 559 | } |
| 560 | |
| 561 | static inline int negifaddoverflows(SkFixed& result, SkFixed a, SkFixed b) { |
| 562 | SkFixed c = a + b; |
| 563 | result = c; |
| 564 | return (c ^ a) & (c ^ b); |
| 565 | } |
| 566 | #endif |
| 567 | |
| 568 | static void normalize_perspective(SkScalar mat[9]) { |
| 569 | if (SkScalarAbs(mat[SkMatrix::kMPersp2]) > kMatrix22Elem) { |
| 570 | for (int i = 0; i < 9; i++) |
| 571 | mat[i] = SkScalarHalf(mat[i]); |
| 572 | } |
| 573 | } |
| 574 | |
| 575 | bool SkMatrix::setConcat(const SkMatrix& a, const SkMatrix& b) { |
| 576 | TypeMask aType = a.getType(); |
| 577 | TypeMask bType = b.getType(); |
| 578 | |
| 579 | if (0 == aType) { |
| 580 | *this = b; |
| 581 | } else if (0 == bType) { |
| 582 | *this = a; |
| 583 | } else { |
| 584 | SkMatrix tmp; |
| 585 | |
| 586 | if ((aType | bType) & kPerspective_Mask) { |
| 587 | if (!rowcol3(&a.fMat[0], &b.fMat[0], &tmp.fMat[kMScaleX])) { |
| 588 | return false; |
| 589 | } |
| 590 | if (!rowcol3(&a.fMat[0], &b.fMat[1], &tmp.fMat[kMSkewX])) { |
| 591 | return false; |
| 592 | } |
| 593 | if (!rowcol3(&a.fMat[0], &b.fMat[2], &tmp.fMat[kMTransX])) { |
| 594 | return false; |
| 595 | } |
| 596 | |
| 597 | if (!rowcol3(&a.fMat[3], &b.fMat[0], &tmp.fMat[kMSkewY])) { |
| 598 | return false; |
| 599 | } |
| 600 | if (!rowcol3(&a.fMat[3], &b.fMat[1], &tmp.fMat[kMScaleY])) { |
| 601 | return false; |
| 602 | } |
| 603 | if (!rowcol3(&a.fMat[3], &b.fMat[2], &tmp.fMat[kMTransY])) { |
| 604 | return false; |
| 605 | } |
| 606 | |
| 607 | if (!rowcol3(&a.fMat[6], &b.fMat[0], &tmp.fMat[kMPersp0])) { |
| 608 | return false; |
| 609 | } |
| 610 | if (!rowcol3(&a.fMat[6], &b.fMat[1], &tmp.fMat[kMPersp1])) { |
| 611 | return false; |
| 612 | } |
| 613 | if (!rowcol3(&a.fMat[6], &b.fMat[2], &tmp.fMat[kMPersp2])) { |
| 614 | return false; |
| 615 | } |
| 616 | |
| 617 | normalize_perspective(tmp.fMat); |
| 618 | } else { // not perspective |
| 619 | if (!fixmuladdmul(a.fMat[kMScaleX], b.fMat[kMScaleX], |
| 620 | a.fMat[kMSkewX], b.fMat[kMSkewY], &tmp.fMat[kMScaleX])) { |
| 621 | return false; |
| 622 | } |
| 623 | if (!fixmuladdmul(a.fMat[kMScaleX], b.fMat[kMSkewX], |
| 624 | a.fMat[kMSkewX], b.fMat[kMScaleY], &tmp.fMat[kMSkewX])) { |
| 625 | return false; |
| 626 | } |
| 627 | if (!fixmuladdmul(a.fMat[kMScaleX], b.fMat[kMTransX], |
| 628 | a.fMat[kMSkewX], b.fMat[kMTransY], &tmp.fMat[kMTransX])) { |
| 629 | return false; |
| 630 | } |
| 631 | if (negifaddoverflows(tmp.fMat[kMTransX], tmp.fMat[kMTransX], |
| 632 | a.fMat[kMTransX]) < 0) { |
| 633 | return false; |
| 634 | } |
| 635 | |
| 636 | if (!fixmuladdmul(a.fMat[kMSkewY], b.fMat[kMScaleX], |
| 637 | a.fMat[kMScaleY], b.fMat[kMSkewY], &tmp.fMat[kMSkewY])) { |
| 638 | return false; |
| 639 | } |
| 640 | if (!fixmuladdmul(a.fMat[kMSkewY], b.fMat[kMSkewX], |
| 641 | a.fMat[kMScaleY], b.fMat[kMScaleY], &tmp.fMat[kMScaleY])) { |
| 642 | return false; |
| 643 | } |
| 644 | if (!fixmuladdmul(a.fMat[kMSkewY], b.fMat[kMTransX], |
| 645 | a.fMat[kMScaleY], b.fMat[kMTransY], &tmp.fMat[kMTransY])) { |
| 646 | return false; |
| 647 | } |
| 648 | if (negifaddoverflows(tmp.fMat[kMTransY], tmp.fMat[kMTransY], |
| 649 | a.fMat[kMTransY]) < 0) { |
| 650 | return false; |
| 651 | } |
| 652 | |
| 653 | tmp.fMat[kMPersp0] = tmp.fMat[kMPersp1] = 0; |
| 654 | tmp.fMat[kMPersp2] = kMatrix22Elem; |
| 655 | } |
| 656 | *this = tmp; |
| 657 | } |
| 658 | this->setTypeMask(kUnknown_Mask); |
| 659 | return true; |
| 660 | } |
| 661 | |
| 662 | bool SkMatrix::preConcat(const SkMatrix& mat) { |
| 663 | // check for identity first, so we don't do a needless copy of ourselves |
| 664 | // to ourselves inside setConcat() |
| 665 | return mat.isIdentity() || this->setConcat(*this, mat); |
| 666 | } |
| 667 | |
| 668 | bool SkMatrix::postConcat(const SkMatrix& mat) { |
| 669 | // check for identity first, so we don't do a needless copy of ourselves |
| 670 | // to ourselves inside setConcat() |
| 671 | return mat.isIdentity() || this->setConcat(mat, *this); |
| 672 | } |
| 673 | |
| 674 | /////////////////////////////////////////////////////////////////////////////// |
| 675 | |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 676 | /* Matrix inversion is very expensive, but also the place where keeping |
| 677 | precision may be most important (here and matrix concat). Hence to avoid |
| 678 | bitmap blitting artifacts when walking the inverse, we use doubles for |
| 679 | the intermediate math, even though we know that is more expensive. |
| 680 | The fixed counter part is us using Sk64 for temp calculations. |
| 681 | */ |
| 682 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 683 | #ifdef SK_SCALAR_IS_FLOAT |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 684 | typedef double SkDetScalar; |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 685 | #define SkPerspMul(a, b) SkScalarMul(a, b) |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 686 | #define SkScalarMulShift(a, b, s) SkDoubleToFloat((a) * (b)) |
| 687 | static double sk_inv_determinant(const float mat[9], int isPerspective, |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 688 | int* /* (only used in Fixed case) */) { |
| 689 | double det; |
| 690 | |
| 691 | if (isPerspective) { |
| 692 | det = mat[SkMatrix::kMScaleX] * ((double)mat[SkMatrix::kMScaleY] * mat[SkMatrix::kMPersp2] - (double)mat[SkMatrix::kMTransY] * mat[SkMatrix::kMPersp1]) + |
| 693 | mat[SkMatrix::kMSkewX] * ((double)mat[SkMatrix::kMTransY] * mat[SkMatrix::kMPersp0] - (double)mat[SkMatrix::kMSkewY] * mat[SkMatrix::kMPersp2]) + |
| 694 | mat[SkMatrix::kMTransX] * ((double)mat[SkMatrix::kMSkewY] * mat[SkMatrix::kMPersp1] - (double)mat[SkMatrix::kMScaleY] * mat[SkMatrix::kMPersp0]); |
| 695 | } else { |
| 696 | det = (double)mat[SkMatrix::kMScaleX] * mat[SkMatrix::kMScaleY] - (double)mat[SkMatrix::kMSkewX] * mat[SkMatrix::kMSkewY]; |
| 697 | } |
| 698 | |
senorblanco@chromium.org | 0e21ec0 | 2010-07-20 15:20:01 +0000 | [diff] [blame] | 699 | // Since the determinant is on the order of the cube of the matrix members, |
| 700 | // compare to the cube of the default nearly-zero constant (although an |
| 701 | // estimate of the condition number would be better if it wasn't so expensive). |
| 702 | if (SkScalarNearlyZero((float)det, SK_ScalarNearlyZero * SK_ScalarNearlyZero * SK_ScalarNearlyZero)) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 703 | return 0; |
| 704 | } |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 705 | return 1.0 / det; |
| 706 | } |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 707 | // we declar a,b,c,d to all be doubles, because we want to perform |
| 708 | // double-precision muls and subtract, even though the original values are |
| 709 | // from the matrix, which are floats. |
| 710 | static float inline mul_diff_scale(double a, double b, double c, double d, |
| 711 | double scale) { |
| 712 | return SkDoubleToFloat((a * b - c * d) * scale); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 713 | } |
| 714 | #else |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 715 | typedef SkFixed SkDetScalar; |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 716 | #define SkPerspMul(a, b) SkFractMul(a, b) |
| 717 | #define SkScalarMulShift(a, b, s) SkMulShift(a, b, s) |
| 718 | static void set_muladdmul(Sk64* dst, int32_t a, int32_t b, int32_t c, |
| 719 | int32_t d) { |
| 720 | Sk64 tmp; |
| 721 | dst->setMul(a, b); |
| 722 | tmp.setMul(c, d); |
| 723 | dst->add(tmp); |
| 724 | } |
| 725 | |
| 726 | static SkFixed sk_inv_determinant(const SkFixed mat[9], int isPerspective, |
| 727 | int* shift) { |
| 728 | Sk64 tmp1, tmp2; |
| 729 | |
| 730 | if (isPerspective) { |
| 731 | tmp1.setMul(mat[SkMatrix::kMScaleX], fracmuladdmul(mat[SkMatrix::kMScaleY], mat[SkMatrix::kMPersp2], -mat[SkMatrix::kMTransY], mat[SkMatrix::kMPersp1])); |
| 732 | tmp2.setMul(mat[SkMatrix::kMSkewX], fracmuladdmul(mat[SkMatrix::kMTransY], mat[SkMatrix::kMPersp0], -mat[SkMatrix::kMSkewY], mat[SkMatrix::kMPersp2])); |
| 733 | tmp1.add(tmp2); |
| 734 | tmp2.setMul(mat[SkMatrix::kMTransX], fracmuladdmul(mat[SkMatrix::kMSkewY], mat[SkMatrix::kMPersp1], -mat[SkMatrix::kMScaleY], mat[SkMatrix::kMPersp0])); |
| 735 | tmp1.add(tmp2); |
| 736 | } else { |
| 737 | tmp1.setMul(mat[SkMatrix::kMScaleX], mat[SkMatrix::kMScaleY]); |
| 738 | tmp2.setMul(mat[SkMatrix::kMSkewX], mat[SkMatrix::kMSkewY]); |
| 739 | tmp1.sub(tmp2); |
| 740 | } |
| 741 | |
| 742 | int s = tmp1.getClzAbs(); |
| 743 | *shift = s; |
| 744 | |
| 745 | SkFixed denom; |
| 746 | if (s <= 32) { |
| 747 | denom = tmp1.getShiftRight(33 - s); |
| 748 | } else { |
| 749 | denom = (int32_t)tmp1.fLo << (s - 33); |
| 750 | } |
| 751 | |
| 752 | if (denom == 0) { |
| 753 | return 0; |
| 754 | } |
| 755 | /** This could perhaps be a special fractdiv function, since both of its |
| 756 | arguments are known to have bit 31 clear and bit 30 set (when they |
| 757 | are made positive), thus eliminating the need for calling clz() |
| 758 | */ |
| 759 | return SkFractDiv(SK_Fract1, denom); |
| 760 | } |
| 761 | #endif |
| 762 | |
bungeman@google.com | 1ddd7c3 | 2011-07-13 19:41:55 +0000 | [diff] [blame^] | 763 | void SkMatrix::SetAffineIdentity(SkScalar affine[6]) { |
| 764 | affine[kAScaleX] = SK_Scalar1; |
| 765 | affine[kASkewY] = 0; |
| 766 | affine[kASkewX] = 0; |
| 767 | affine[kAScaleY] = SK_Scalar1; |
| 768 | affine[kATransX] = 0; |
| 769 | affine[kATransY] = 0; |
| 770 | } |
| 771 | |
| 772 | bool SkMatrix::asAffine(SkScalar affine[6]) const { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 773 | if (this->hasPerspective()) { |
bungeman@google.com | 1ddd7c3 | 2011-07-13 19:41:55 +0000 | [diff] [blame^] | 774 | return false; |
vandebo@chromium.org | ddbbd80 | 2010-10-26 19:45:06 +0000 | [diff] [blame] | 775 | } |
bungeman@google.com | 1ddd7c3 | 2011-07-13 19:41:55 +0000 | [diff] [blame^] | 776 | if (affine) { |
| 777 | affine[kAScaleX] = this->fMat[kMScaleX]; |
| 778 | affine[kASkewY] = this->fMat[kMSkewY]; |
| 779 | affine[kASkewX] = this->fMat[kMSkewX]; |
| 780 | affine[kAScaleY] = this->fMat[kMScaleY]; |
| 781 | affine[kATransX] = this->fMat[kMTransX]; |
| 782 | affine[kATransY] = this->fMat[kMTransY]; |
| 783 | } |
vandebo@chromium.org | ddbbd80 | 2010-10-26 19:45:06 +0000 | [diff] [blame] | 784 | return true; |
| 785 | } |
| 786 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 787 | bool SkMatrix::invert(SkMatrix* inv) const { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 788 | int isPersp = this->hasPerspective(); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 789 | int shift; |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 790 | SkDetScalar scale = sk_inv_determinant(fMat, isPersp, &shift); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 791 | |
| 792 | if (scale == 0) { // underflow |
| 793 | return false; |
| 794 | } |
| 795 | |
| 796 | if (inv) { |
| 797 | SkMatrix tmp; |
| 798 | if (inv == this) |
| 799 | inv = &tmp; |
| 800 | |
| 801 | if (isPersp) { |
| 802 | shift = 61 - shift; |
| 803 | inv->fMat[kMScaleX] = SkScalarMulShift(SkPerspMul(fMat[kMScaleY], fMat[kMPersp2]) - SkPerspMul(fMat[kMTransY], fMat[kMPersp1]), scale, shift); |
| 804 | inv->fMat[kMSkewX] = SkScalarMulShift(SkPerspMul(fMat[kMTransX], fMat[kMPersp1]) - SkPerspMul(fMat[kMSkewX], fMat[kMPersp2]), scale, shift); |
| 805 | inv->fMat[kMTransX] = SkScalarMulShift(SkScalarMul(fMat[kMSkewX], fMat[kMTransY]) - SkScalarMul(fMat[kMTransX], fMat[kMScaleY]), scale, shift); |
| 806 | |
| 807 | inv->fMat[kMSkewY] = SkScalarMulShift(SkPerspMul(fMat[kMTransY], fMat[kMPersp0]) - SkPerspMul(fMat[kMSkewY], fMat[kMPersp2]), scale, shift); |
| 808 | inv->fMat[kMScaleY] = SkScalarMulShift(SkPerspMul(fMat[kMScaleX], fMat[kMPersp2]) - SkPerspMul(fMat[kMTransX], fMat[kMPersp0]), scale, shift); |
| 809 | inv->fMat[kMTransY] = SkScalarMulShift(SkScalarMul(fMat[kMTransX], fMat[kMSkewY]) - SkScalarMul(fMat[kMScaleX], fMat[kMTransY]), scale, shift); |
| 810 | |
| 811 | inv->fMat[kMPersp0] = SkScalarMulShift(SkScalarMul(fMat[kMSkewY], fMat[kMPersp1]) - SkScalarMul(fMat[kMScaleY], fMat[kMPersp0]), scale, shift); |
| 812 | inv->fMat[kMPersp1] = SkScalarMulShift(SkScalarMul(fMat[kMSkewX], fMat[kMPersp0]) - SkScalarMul(fMat[kMScaleX], fMat[kMPersp1]), scale, shift); |
| 813 | inv->fMat[kMPersp2] = SkScalarMulShift(SkScalarMul(fMat[kMScaleX], fMat[kMScaleY]) - SkScalarMul(fMat[kMSkewX], fMat[kMSkewY]), scale, shift); |
| 814 | #ifdef SK_SCALAR_IS_FIXED |
| 815 | if (SkAbs32(inv->fMat[kMPersp2]) > SK_Fixed1) { |
| 816 | Sk64 tmp; |
| 817 | |
| 818 | tmp.set(SK_Fract1); |
| 819 | tmp.shiftLeft(16); |
| 820 | tmp.div(inv->fMat[kMPersp2], Sk64::kRound_DivOption); |
| 821 | |
| 822 | SkFract scale = tmp.get32(); |
| 823 | |
| 824 | for (int i = 0; i < 9; i++) { |
| 825 | inv->fMat[i] = SkFractMul(inv->fMat[i], scale); |
| 826 | } |
| 827 | } |
| 828 | inv->fMat[kMPersp2] = SkFixedToFract(inv->fMat[kMPersp2]); |
| 829 | #endif |
| 830 | } else { // not perspective |
| 831 | #ifdef SK_SCALAR_IS_FIXED |
| 832 | Sk64 tx, ty; |
| 833 | int clzNumer; |
| 834 | |
| 835 | // check the 2x2 for overflow |
| 836 | { |
| 837 | int32_t value = SkAbs32(fMat[kMScaleY]); |
| 838 | value |= SkAbs32(fMat[kMSkewX]); |
| 839 | value |= SkAbs32(fMat[kMScaleX]); |
| 840 | value |= SkAbs32(fMat[kMSkewY]); |
| 841 | clzNumer = SkCLZ(value); |
| 842 | if (shift - clzNumer > 31) |
| 843 | return false; // overflow |
| 844 | } |
| 845 | |
| 846 | set_muladdmul(&tx, fMat[kMSkewX], fMat[kMTransY], -fMat[kMScaleY], fMat[kMTransX]); |
| 847 | set_muladdmul(&ty, fMat[kMSkewY], fMat[kMTransX], -fMat[kMScaleX], fMat[kMTransY]); |
| 848 | // check tx,ty for overflow |
| 849 | clzNumer = SkCLZ(SkAbs32(tx.fHi) | SkAbs32(ty.fHi)); |
| 850 | if (shift - clzNumer > 14) { |
| 851 | return false; // overflow |
| 852 | } |
| 853 | |
| 854 | int fixedShift = 61 - shift; |
| 855 | int sk64shift = 44 - shift + clzNumer; |
| 856 | |
| 857 | inv->fMat[kMScaleX] = SkMulShift(fMat[kMScaleY], scale, fixedShift); |
| 858 | inv->fMat[kMSkewX] = SkMulShift(-fMat[kMSkewX], scale, fixedShift); |
| 859 | inv->fMat[kMTransX] = SkMulShift(tx.getShiftRight(33 - clzNumer), scale, sk64shift); |
| 860 | |
| 861 | inv->fMat[kMSkewY] = SkMulShift(-fMat[kMSkewY], scale, fixedShift); |
| 862 | inv->fMat[kMScaleY] = SkMulShift(fMat[kMScaleX], scale, fixedShift); |
| 863 | inv->fMat[kMTransY] = SkMulShift(ty.getShiftRight(33 - clzNumer), scale, sk64shift); |
| 864 | #else |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 865 | inv->fMat[kMScaleX] = SkDoubleToFloat(fMat[kMScaleY] * scale); |
| 866 | inv->fMat[kMSkewX] = SkDoubleToFloat(-fMat[kMSkewX] * scale); |
| 867 | inv->fMat[kMTransX] = mul_diff_scale(fMat[kMSkewX], fMat[kMTransY], |
| 868 | fMat[kMScaleY], fMat[kMTransX], scale); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 869 | |
reed@android.com | 0b9e2db | 2009-09-16 17:00:17 +0000 | [diff] [blame] | 870 | inv->fMat[kMSkewY] = SkDoubleToFloat(-fMat[kMSkewY] * scale); |
| 871 | inv->fMat[kMScaleY] = SkDoubleToFloat(fMat[kMScaleX] * scale); |
| 872 | inv->fMat[kMTransY] = mul_diff_scale(fMat[kMSkewY], fMat[kMTransX], |
| 873 | fMat[kMScaleX], fMat[kMTransY], scale); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 874 | #endif |
| 875 | inv->fMat[kMPersp0] = 0; |
| 876 | inv->fMat[kMPersp1] = 0; |
| 877 | inv->fMat[kMPersp2] = kMatrix22Elem; |
| 878 | } |
| 879 | |
| 880 | if (inv == &tmp) { |
| 881 | *(SkMatrix*)this = tmp; |
| 882 | } |
| 883 | inv->setTypeMask(kUnknown_Mask); |
| 884 | } |
| 885 | return true; |
| 886 | } |
| 887 | |
| 888 | /////////////////////////////////////////////////////////////////////////////// |
| 889 | |
| 890 | void SkMatrix::Identity_pts(const SkMatrix& m, SkPoint dst[], |
| 891 | const SkPoint src[], int count) { |
| 892 | SkASSERT(m.getType() == 0); |
| 893 | |
| 894 | if (dst != src && count > 0) |
| 895 | memcpy(dst, src, count * sizeof(SkPoint)); |
| 896 | } |
| 897 | |
| 898 | void SkMatrix::Trans_pts(const SkMatrix& m, SkPoint dst[], |
| 899 | const SkPoint src[], int count) { |
| 900 | SkASSERT(m.getType() == kTranslate_Mask); |
| 901 | |
| 902 | if (count > 0) { |
| 903 | SkScalar tx = m.fMat[kMTransX]; |
| 904 | SkScalar ty = m.fMat[kMTransY]; |
| 905 | do { |
| 906 | dst->fY = src->fY + ty; |
| 907 | dst->fX = src->fX + tx; |
| 908 | src += 1; |
| 909 | dst += 1; |
| 910 | } while (--count); |
| 911 | } |
| 912 | } |
| 913 | |
| 914 | void SkMatrix::Scale_pts(const SkMatrix& m, SkPoint dst[], |
| 915 | const SkPoint src[], int count) { |
| 916 | SkASSERT(m.getType() == kScale_Mask); |
| 917 | |
| 918 | if (count > 0) { |
| 919 | SkScalar mx = m.fMat[kMScaleX]; |
| 920 | SkScalar my = m.fMat[kMScaleY]; |
| 921 | do { |
| 922 | dst->fY = SkScalarMul(src->fY, my); |
| 923 | dst->fX = SkScalarMul(src->fX, mx); |
| 924 | src += 1; |
| 925 | dst += 1; |
| 926 | } while (--count); |
| 927 | } |
| 928 | } |
| 929 | |
| 930 | void SkMatrix::ScaleTrans_pts(const SkMatrix& m, SkPoint dst[], |
| 931 | const SkPoint src[], int count) { |
| 932 | SkASSERT(m.getType() == (kScale_Mask | kTranslate_Mask)); |
| 933 | |
| 934 | if (count > 0) { |
| 935 | SkScalar mx = m.fMat[kMScaleX]; |
| 936 | SkScalar my = m.fMat[kMScaleY]; |
| 937 | SkScalar tx = m.fMat[kMTransX]; |
| 938 | SkScalar ty = m.fMat[kMTransY]; |
| 939 | do { |
| 940 | dst->fY = SkScalarMulAdd(src->fY, my, ty); |
| 941 | dst->fX = SkScalarMulAdd(src->fX, mx, tx); |
| 942 | src += 1; |
| 943 | dst += 1; |
| 944 | } while (--count); |
| 945 | } |
| 946 | } |
| 947 | |
| 948 | void SkMatrix::Rot_pts(const SkMatrix& m, SkPoint dst[], |
| 949 | const SkPoint src[], int count) { |
| 950 | SkASSERT((m.getType() & (kPerspective_Mask | kTranslate_Mask)) == 0); |
| 951 | |
| 952 | if (count > 0) { |
| 953 | SkScalar mx = m.fMat[kMScaleX]; |
| 954 | SkScalar my = m.fMat[kMScaleY]; |
| 955 | SkScalar kx = m.fMat[kMSkewX]; |
| 956 | SkScalar ky = m.fMat[kMSkewY]; |
| 957 | do { |
| 958 | SkScalar sy = src->fY; |
| 959 | SkScalar sx = src->fX; |
| 960 | src += 1; |
| 961 | dst->fY = SkScalarMul(sx, ky) + SkScalarMul(sy, my); |
| 962 | dst->fX = SkScalarMul(sx, mx) + SkScalarMul(sy, kx); |
| 963 | dst += 1; |
| 964 | } while (--count); |
| 965 | } |
| 966 | } |
| 967 | |
| 968 | void SkMatrix::RotTrans_pts(const SkMatrix& m, SkPoint dst[], |
| 969 | const SkPoint src[], int count) { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 970 | SkASSERT(!m.hasPerspective()); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 971 | |
| 972 | if (count > 0) { |
| 973 | SkScalar mx = m.fMat[kMScaleX]; |
| 974 | SkScalar my = m.fMat[kMScaleY]; |
| 975 | SkScalar kx = m.fMat[kMSkewX]; |
| 976 | SkScalar ky = m.fMat[kMSkewY]; |
| 977 | SkScalar tx = m.fMat[kMTransX]; |
| 978 | SkScalar ty = m.fMat[kMTransY]; |
| 979 | do { |
| 980 | SkScalar sy = src->fY; |
| 981 | SkScalar sx = src->fX; |
| 982 | src += 1; |
| 983 | dst->fY = SkScalarMul(sx, ky) + SkScalarMulAdd(sy, my, ty); |
| 984 | dst->fX = SkScalarMul(sx, mx) + SkScalarMulAdd(sy, kx, tx); |
| 985 | dst += 1; |
| 986 | } while (--count); |
| 987 | } |
| 988 | } |
| 989 | |
| 990 | void SkMatrix::Persp_pts(const SkMatrix& m, SkPoint dst[], |
| 991 | const SkPoint src[], int count) { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 992 | SkASSERT(m.hasPerspective()); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 993 | |
| 994 | #ifdef SK_SCALAR_IS_FIXED |
| 995 | SkFixed persp2 = SkFractToFixed(m.fMat[kMPersp2]); |
| 996 | #endif |
| 997 | |
| 998 | if (count > 0) { |
| 999 | do { |
| 1000 | SkScalar sy = src->fY; |
| 1001 | SkScalar sx = src->fX; |
| 1002 | src += 1; |
| 1003 | |
| 1004 | SkScalar x = SkScalarMul(sx, m.fMat[kMScaleX]) + |
| 1005 | SkScalarMul(sy, m.fMat[kMSkewX]) + m.fMat[kMTransX]; |
| 1006 | SkScalar y = SkScalarMul(sx, m.fMat[kMSkewY]) + |
| 1007 | SkScalarMul(sy, m.fMat[kMScaleY]) + m.fMat[kMTransY]; |
| 1008 | #ifdef SK_SCALAR_IS_FIXED |
| 1009 | SkFixed z = SkFractMul(sx, m.fMat[kMPersp0]) + |
| 1010 | SkFractMul(sy, m.fMat[kMPersp1]) + persp2; |
| 1011 | #else |
| 1012 | float z = SkScalarMul(sx, m.fMat[kMPersp0]) + |
| 1013 | SkScalarMulAdd(sy, m.fMat[kMPersp1], m.fMat[kMPersp2]); |
| 1014 | #endif |
| 1015 | if (z) { |
| 1016 | z = SkScalarFastInvert(z); |
| 1017 | } |
| 1018 | |
| 1019 | dst->fY = SkScalarMul(y, z); |
| 1020 | dst->fX = SkScalarMul(x, z); |
| 1021 | dst += 1; |
| 1022 | } while (--count); |
| 1023 | } |
| 1024 | } |
| 1025 | |
| 1026 | const SkMatrix::MapPtsProc SkMatrix::gMapPtsProcs[] = { |
| 1027 | SkMatrix::Identity_pts, SkMatrix::Trans_pts, |
| 1028 | SkMatrix::Scale_pts, SkMatrix::ScaleTrans_pts, |
| 1029 | SkMatrix::Rot_pts, SkMatrix::RotTrans_pts, |
| 1030 | SkMatrix::Rot_pts, SkMatrix::RotTrans_pts, |
| 1031 | // repeat the persp proc 8 times |
| 1032 | SkMatrix::Persp_pts, SkMatrix::Persp_pts, |
| 1033 | SkMatrix::Persp_pts, SkMatrix::Persp_pts, |
| 1034 | SkMatrix::Persp_pts, SkMatrix::Persp_pts, |
| 1035 | SkMatrix::Persp_pts, SkMatrix::Persp_pts |
| 1036 | }; |
| 1037 | |
| 1038 | void SkMatrix::mapPoints(SkPoint dst[], const SkPoint src[], int count) const { |
| 1039 | SkASSERT((dst && src && count > 0) || count == 0); |
| 1040 | // no partial overlap |
| 1041 | SkASSERT(src == dst || SkAbs32((int32_t)(src - dst)) >= count); |
| 1042 | |
| 1043 | this->getMapPtsProc()(*this, dst, src, count); |
| 1044 | } |
| 1045 | |
| 1046 | /////////////////////////////////////////////////////////////////////////////// |
| 1047 | |
| 1048 | void SkMatrix::mapVectors(SkPoint dst[], const SkPoint src[], int count) const { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 1049 | if (this->hasPerspective()) { |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 1050 | SkPoint origin; |
| 1051 | |
| 1052 | MapXYProc proc = this->getMapXYProc(); |
| 1053 | proc(*this, 0, 0, &origin); |
| 1054 | |
| 1055 | for (int i = count - 1; i >= 0; --i) { |
| 1056 | SkPoint tmp; |
| 1057 | |
| 1058 | proc(*this, src[i].fX, src[i].fY, &tmp); |
| 1059 | dst[i].set(tmp.fX - origin.fX, tmp.fY - origin.fY); |
| 1060 | } |
| 1061 | } else { |
| 1062 | SkMatrix tmp = *this; |
| 1063 | |
| 1064 | tmp.fMat[kMTransX] = tmp.fMat[kMTransY] = 0; |
| 1065 | tmp.clearTypeMask(kTranslate_Mask); |
| 1066 | tmp.mapPoints(dst, src, count); |
| 1067 | } |
| 1068 | } |
| 1069 | |
| 1070 | bool SkMatrix::mapRect(SkRect* dst, const SkRect& src) const { |
| 1071 | SkASSERT(dst && &src); |
| 1072 | |
| 1073 | if (this->rectStaysRect()) { |
| 1074 | this->mapPoints((SkPoint*)dst, (const SkPoint*)&src, 2); |
| 1075 | dst->sort(); |
| 1076 | return true; |
| 1077 | } else { |
| 1078 | SkPoint quad[4]; |
| 1079 | |
| 1080 | src.toQuad(quad); |
| 1081 | this->mapPoints(quad, quad, 4); |
| 1082 | dst->set(quad, 4); |
| 1083 | return false; |
| 1084 | } |
| 1085 | } |
| 1086 | |
| 1087 | SkScalar SkMatrix::mapRadius(SkScalar radius) const { |
| 1088 | SkVector vec[2]; |
| 1089 | |
| 1090 | vec[0].set(radius, 0); |
| 1091 | vec[1].set(0, radius); |
| 1092 | this->mapVectors(vec, 2); |
| 1093 | |
| 1094 | SkScalar d0 = vec[0].length(); |
| 1095 | SkScalar d1 = vec[1].length(); |
| 1096 | |
| 1097 | return SkScalarMean(d0, d1); |
| 1098 | } |
| 1099 | |
| 1100 | /////////////////////////////////////////////////////////////////////////////// |
| 1101 | |
| 1102 | void SkMatrix::Persp_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1103 | SkPoint* pt) { |
tomhudson@google.com | 8d43018 | 2011-06-06 19:11:19 +0000 | [diff] [blame] | 1104 | SkASSERT(m.hasPerspective()); |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 1105 | |
| 1106 | SkScalar x = SkScalarMul(sx, m.fMat[kMScaleX]) + |
| 1107 | SkScalarMul(sy, m.fMat[kMSkewX]) + m.fMat[kMTransX]; |
| 1108 | SkScalar y = SkScalarMul(sx, m.fMat[kMSkewY]) + |
| 1109 | SkScalarMul(sy, m.fMat[kMScaleY]) + m.fMat[kMTransY]; |
| 1110 | #ifdef SK_SCALAR_IS_FIXED |
| 1111 | SkFixed z = SkFractMul(sx, m.fMat[kMPersp0]) + |
| 1112 | SkFractMul(sy, m.fMat[kMPersp1]) + |
| 1113 | SkFractToFixed(m.fMat[kMPersp2]); |
| 1114 | #else |
| 1115 | float z = SkScalarMul(sx, m.fMat[kMPersp0]) + |
| 1116 | SkScalarMul(sy, m.fMat[kMPersp1]) + m.fMat[kMPersp2]; |
| 1117 | #endif |
| 1118 | if (z) { |
| 1119 | z = SkScalarFastInvert(z); |
| 1120 | } |
| 1121 | pt->fX = SkScalarMul(x, z); |
| 1122 | pt->fY = SkScalarMul(y, z); |
| 1123 | } |
| 1124 | |
| 1125 | #ifdef SK_SCALAR_IS_FIXED |
| 1126 | static SkFixed fixmuladdmul(SkFixed a, SkFixed b, SkFixed c, SkFixed d) { |
| 1127 | Sk64 tmp, tmp1; |
| 1128 | |
| 1129 | tmp.setMul(a, b); |
| 1130 | tmp1.setMul(c, d); |
| 1131 | return tmp.addGetFixed(tmp1); |
| 1132 | // tmp.add(tmp1); |
| 1133 | // return tmp.getFixed(); |
| 1134 | } |
| 1135 | #endif |
| 1136 | |
| 1137 | void SkMatrix::RotTrans_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1138 | SkPoint* pt) { |
| 1139 | SkASSERT((m.getType() & (kAffine_Mask | kPerspective_Mask)) == kAffine_Mask); |
| 1140 | |
| 1141 | #ifdef SK_SCALAR_IS_FIXED |
| 1142 | pt->fX = fixmuladdmul(sx, m.fMat[kMScaleX], sy, m.fMat[kMSkewX]) + |
| 1143 | m.fMat[kMTransX]; |
| 1144 | pt->fY = fixmuladdmul(sx, m.fMat[kMSkewY], sy, m.fMat[kMScaleY]) + |
| 1145 | m.fMat[kMTransY]; |
| 1146 | #else |
| 1147 | pt->fX = SkScalarMul(sx, m.fMat[kMScaleX]) + |
| 1148 | SkScalarMulAdd(sy, m.fMat[kMSkewX], m.fMat[kMTransX]); |
| 1149 | pt->fY = SkScalarMul(sx, m.fMat[kMSkewY]) + |
| 1150 | SkScalarMulAdd(sy, m.fMat[kMScaleY], m.fMat[kMTransY]); |
| 1151 | #endif |
| 1152 | } |
| 1153 | |
| 1154 | void SkMatrix::Rot_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1155 | SkPoint* pt) { |
| 1156 | SkASSERT((m.getType() & (kAffine_Mask | kPerspective_Mask))== kAffine_Mask); |
| 1157 | SkASSERT(0 == m.fMat[kMTransX]); |
| 1158 | SkASSERT(0 == m.fMat[kMTransY]); |
| 1159 | |
| 1160 | #ifdef SK_SCALAR_IS_FIXED |
| 1161 | pt->fX = fixmuladdmul(sx, m.fMat[kMScaleX], sy, m.fMat[kMSkewX]); |
| 1162 | pt->fY = fixmuladdmul(sx, m.fMat[kMSkewY], sy, m.fMat[kMScaleY]); |
| 1163 | #else |
| 1164 | pt->fX = SkScalarMul(sx, m.fMat[kMScaleX]) + |
| 1165 | SkScalarMulAdd(sy, m.fMat[kMSkewX], m.fMat[kMTransX]); |
| 1166 | pt->fY = SkScalarMul(sx, m.fMat[kMSkewY]) + |
| 1167 | SkScalarMulAdd(sy, m.fMat[kMScaleY], m.fMat[kMTransY]); |
| 1168 | #endif |
| 1169 | } |
| 1170 | |
| 1171 | void SkMatrix::ScaleTrans_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1172 | SkPoint* pt) { |
| 1173 | SkASSERT((m.getType() & (kScale_Mask | kAffine_Mask | kPerspective_Mask)) |
| 1174 | == kScale_Mask); |
| 1175 | |
| 1176 | pt->fX = SkScalarMulAdd(sx, m.fMat[kMScaleX], m.fMat[kMTransX]); |
| 1177 | pt->fY = SkScalarMulAdd(sy, m.fMat[kMScaleY], m.fMat[kMTransY]); |
| 1178 | } |
| 1179 | |
| 1180 | void SkMatrix::Scale_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1181 | SkPoint* pt) { |
| 1182 | SkASSERT((m.getType() & (kScale_Mask | kAffine_Mask | kPerspective_Mask)) |
| 1183 | == kScale_Mask); |
| 1184 | SkASSERT(0 == m.fMat[kMTransX]); |
| 1185 | SkASSERT(0 == m.fMat[kMTransY]); |
| 1186 | |
| 1187 | pt->fX = SkScalarMul(sx, m.fMat[kMScaleX]); |
| 1188 | pt->fY = SkScalarMul(sy, m.fMat[kMScaleY]); |
| 1189 | } |
| 1190 | |
| 1191 | void SkMatrix::Trans_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1192 | SkPoint* pt) { |
| 1193 | SkASSERT(m.getType() == kTranslate_Mask); |
| 1194 | |
| 1195 | pt->fX = sx + m.fMat[kMTransX]; |
| 1196 | pt->fY = sy + m.fMat[kMTransY]; |
| 1197 | } |
| 1198 | |
| 1199 | void SkMatrix::Identity_xy(const SkMatrix& m, SkScalar sx, SkScalar sy, |
| 1200 | SkPoint* pt) { |
| 1201 | SkASSERT(0 == m.getType()); |
| 1202 | |
| 1203 | pt->fX = sx; |
| 1204 | pt->fY = sy; |
| 1205 | } |
| 1206 | |
| 1207 | const SkMatrix::MapXYProc SkMatrix::gMapXYProcs[] = { |
| 1208 | SkMatrix::Identity_xy, SkMatrix::Trans_xy, |
| 1209 | SkMatrix::Scale_xy, SkMatrix::ScaleTrans_xy, |
| 1210 | SkMatrix::Rot_xy, SkMatrix::RotTrans_xy, |
| 1211 | SkMatrix::Rot_xy, SkMatrix::RotTrans_xy, |
| 1212 | // repeat the persp proc 8 times |
| 1213 | SkMatrix::Persp_xy, SkMatrix::Persp_xy, |
| 1214 | SkMatrix::Persp_xy, SkMatrix::Persp_xy, |
| 1215 | SkMatrix::Persp_xy, SkMatrix::Persp_xy, |
| 1216 | SkMatrix::Persp_xy, SkMatrix::Persp_xy |
| 1217 | }; |
| 1218 | |
| 1219 | /////////////////////////////////////////////////////////////////////////////// |
| 1220 | |
| 1221 | // if its nearly zero (just made up 26, perhaps it should be bigger or smaller) |
| 1222 | #ifdef SK_SCALAR_IS_FIXED |
| 1223 | typedef SkFract SkPerspElemType; |
| 1224 | #define PerspNearlyZero(x) (SkAbs32(x) < (SK_Fract1 >> 26)) |
| 1225 | #else |
| 1226 | typedef float SkPerspElemType; |
| 1227 | #define PerspNearlyZero(x) SkScalarNearlyZero(x, (1.0f / (1 << 26))) |
| 1228 | #endif |
| 1229 | |
| 1230 | bool SkMatrix::fixedStepInX(SkScalar y, SkFixed* stepX, SkFixed* stepY) const { |
| 1231 | if (PerspNearlyZero(fMat[kMPersp0])) { |
| 1232 | if (stepX || stepY) { |
| 1233 | if (PerspNearlyZero(fMat[kMPersp1]) && |
| 1234 | PerspNearlyZero(fMat[kMPersp2] - kMatrix22Elem)) { |
| 1235 | if (stepX) { |
| 1236 | *stepX = SkScalarToFixed(fMat[kMScaleX]); |
| 1237 | } |
| 1238 | if (stepY) { |
| 1239 | *stepY = SkScalarToFixed(fMat[kMSkewY]); |
| 1240 | } |
| 1241 | } else { |
| 1242 | #ifdef SK_SCALAR_IS_FIXED |
| 1243 | SkFixed z = SkFractMul(y, fMat[kMPersp1]) + |
| 1244 | SkFractToFixed(fMat[kMPersp2]); |
| 1245 | #else |
| 1246 | float z = y * fMat[kMPersp1] + fMat[kMPersp2]; |
| 1247 | #endif |
| 1248 | if (stepX) { |
| 1249 | *stepX = SkScalarToFixed(SkScalarDiv(fMat[kMScaleX], z)); |
| 1250 | } |
| 1251 | if (stepY) { |
| 1252 | *stepY = SkScalarToFixed(SkScalarDiv(fMat[kMSkewY], z)); |
| 1253 | } |
| 1254 | } |
| 1255 | } |
| 1256 | return true; |
| 1257 | } |
| 1258 | return false; |
| 1259 | } |
| 1260 | |
| 1261 | /////////////////////////////////////////////////////////////////////////////// |
| 1262 | |
| 1263 | #include "SkPerspIter.h" |
| 1264 | |
| 1265 | SkPerspIter::SkPerspIter(const SkMatrix& m, SkScalar x0, SkScalar y0, int count) |
| 1266 | : fMatrix(m), fSX(x0), fSY(y0), fCount(count) { |
| 1267 | SkPoint pt; |
| 1268 | |
| 1269 | SkMatrix::Persp_xy(m, x0, y0, &pt); |
| 1270 | fX = SkScalarToFixed(pt.fX); |
| 1271 | fY = SkScalarToFixed(pt.fY); |
| 1272 | } |
| 1273 | |
| 1274 | int SkPerspIter::next() { |
| 1275 | int n = fCount; |
| 1276 | |
| 1277 | if (0 == n) { |
| 1278 | return 0; |
| 1279 | } |
| 1280 | SkPoint pt; |
| 1281 | SkFixed x = fX; |
| 1282 | SkFixed y = fY; |
| 1283 | SkFixed dx, dy; |
| 1284 | |
| 1285 | if (n >= kCount) { |
| 1286 | n = kCount; |
| 1287 | fSX += SkIntToScalar(kCount); |
| 1288 | SkMatrix::Persp_xy(fMatrix, fSX, fSY, &pt); |
| 1289 | fX = SkScalarToFixed(pt.fX); |
| 1290 | fY = SkScalarToFixed(pt.fY); |
| 1291 | dx = (fX - x) >> kShift; |
| 1292 | dy = (fY - y) >> kShift; |
| 1293 | } else { |
| 1294 | fSX += SkIntToScalar(n); |
| 1295 | SkMatrix::Persp_xy(fMatrix, fSX, fSY, &pt); |
| 1296 | fX = SkScalarToFixed(pt.fX); |
| 1297 | fY = SkScalarToFixed(pt.fY); |
| 1298 | dx = (fX - x) / n; |
| 1299 | dy = (fY - y) / n; |
| 1300 | } |
| 1301 | |
| 1302 | SkFixed* p = fStorage; |
| 1303 | for (int i = 0; i < n; i++) { |
| 1304 | *p++ = x; x += dx; |
| 1305 | *p++ = y; y += dy; |
| 1306 | } |
| 1307 | |
| 1308 | fCount -= n; |
| 1309 | return n; |
| 1310 | } |
| 1311 | |
| 1312 | /////////////////////////////////////////////////////////////////////////////// |
| 1313 | |
| 1314 | #ifdef SK_SCALAR_IS_FIXED |
| 1315 | |
| 1316 | static inline bool poly_to_point(SkPoint* pt, const SkPoint poly[], int count) { |
| 1317 | SkFixed x = SK_Fixed1, y = SK_Fixed1; |
| 1318 | SkPoint pt1, pt2; |
| 1319 | Sk64 w1, w2; |
| 1320 | |
| 1321 | if (count > 1) { |
| 1322 | pt1.fX = poly[1].fX - poly[0].fX; |
| 1323 | pt1.fY = poly[1].fY - poly[0].fY; |
| 1324 | y = SkPoint::Length(pt1.fX, pt1.fY); |
| 1325 | if (y == 0) { |
| 1326 | return false; |
| 1327 | } |
| 1328 | switch (count) { |
| 1329 | case 2: |
| 1330 | break; |
| 1331 | case 3: |
| 1332 | pt2.fX = poly[0].fY - poly[2].fY; |
| 1333 | pt2.fY = poly[2].fX - poly[0].fX; |
| 1334 | goto CALC_X; |
| 1335 | default: |
| 1336 | pt2.fX = poly[0].fY - poly[3].fY; |
| 1337 | pt2.fY = poly[3].fX - poly[0].fX; |
| 1338 | CALC_X: |
| 1339 | w1.setMul(pt1.fX, pt2.fX); |
| 1340 | w2.setMul(pt1.fY, pt2.fY); |
| 1341 | w1.add(w2); |
| 1342 | w1.div(y, Sk64::kRound_DivOption); |
| 1343 | if (!w1.is32()) { |
| 1344 | return false; |
| 1345 | } |
| 1346 | x = w1.get32(); |
| 1347 | break; |
| 1348 | } |
| 1349 | } |
| 1350 | pt->set(x, y); |
| 1351 | return true; |
| 1352 | } |
| 1353 | |
| 1354 | bool SkMatrix::Poly2Proc(const SkPoint srcPt[], SkMatrix* dst, |
| 1355 | const SkPoint& scalePt) { |
| 1356 | // need to check if SkFixedDiv overflows... |
| 1357 | |
| 1358 | const SkFixed scale = scalePt.fY; |
| 1359 | dst->fMat[kMScaleX] = SkFixedDiv(srcPt[1].fY - srcPt[0].fY, scale); |
| 1360 | dst->fMat[kMSkewY] = SkFixedDiv(srcPt[0].fX - srcPt[1].fX, scale); |
| 1361 | dst->fMat[kMPersp0] = 0; |
| 1362 | dst->fMat[kMSkewX] = SkFixedDiv(srcPt[1].fX - srcPt[0].fX, scale); |
| 1363 | dst->fMat[kMScaleY] = SkFixedDiv(srcPt[1].fY - srcPt[0].fY, scale); |
| 1364 | dst->fMat[kMPersp1] = 0; |
| 1365 | dst->fMat[kMTransX] = srcPt[0].fX; |
| 1366 | dst->fMat[kMTransY] = srcPt[0].fY; |
| 1367 | dst->fMat[kMPersp2] = SK_Fract1; |
| 1368 | dst->setTypeMask(kUnknown_Mask); |
| 1369 | return true; |
| 1370 | } |
| 1371 | |
| 1372 | bool SkMatrix::Poly3Proc(const SkPoint srcPt[], SkMatrix* dst, |
| 1373 | const SkPoint& scale) { |
| 1374 | // really, need to check if SkFixedDiv overflow'd |
| 1375 | |
| 1376 | dst->fMat[kMScaleX] = SkFixedDiv(srcPt[2].fX - srcPt[0].fX, scale.fX); |
| 1377 | dst->fMat[kMSkewY] = SkFixedDiv(srcPt[2].fY - srcPt[0].fY, scale.fX); |
| 1378 | dst->fMat[kMPersp0] = 0; |
| 1379 | dst->fMat[kMSkewX] = SkFixedDiv(srcPt[1].fX - srcPt[0].fX, scale.fY); |
| 1380 | dst->fMat[kMScaleY] = SkFixedDiv(srcPt[1].fY - srcPt[0].fY, scale.fY); |
| 1381 | dst->fMat[kMPersp1] = 0; |
| 1382 | dst->fMat[kMTransX] = srcPt[0].fX; |
| 1383 | dst->fMat[kMTransY] = srcPt[0].fY; |
| 1384 | dst->fMat[kMPersp2] = SK_Fract1; |
| 1385 | dst->setTypeMask(kUnknown_Mask); |
| 1386 | return true; |
| 1387 | } |
| 1388 | |
| 1389 | bool SkMatrix::Poly4Proc(const SkPoint srcPt[], SkMatrix* dst, |
| 1390 | const SkPoint& scale) { |
| 1391 | SkFract a1, a2; |
| 1392 | SkFixed x0, y0, x1, y1, x2, y2; |
| 1393 | |
| 1394 | x0 = srcPt[2].fX - srcPt[0].fX; |
| 1395 | y0 = srcPt[2].fY - srcPt[0].fY; |
| 1396 | x1 = srcPt[2].fX - srcPt[1].fX; |
| 1397 | y1 = srcPt[2].fY - srcPt[1].fY; |
| 1398 | x2 = srcPt[2].fX - srcPt[3].fX; |
| 1399 | y2 = srcPt[2].fY - srcPt[3].fY; |
| 1400 | |
| 1401 | /* check if abs(x2) > abs(y2) */ |
| 1402 | if ( x2 > 0 ? y2 > 0 ? x2 > y2 : x2 > -y2 : y2 > 0 ? -x2 > y2 : x2 < y2) { |
| 1403 | SkFixed denom = SkMulDiv(x1, y2, x2) - y1; |
| 1404 | if (0 == denom) { |
| 1405 | return false; |
| 1406 | } |
| 1407 | a1 = SkFractDiv(SkMulDiv(x0 - x1, y2, x2) - y0 + y1, denom); |
| 1408 | } else { |
| 1409 | SkFixed denom = x1 - SkMulDiv(y1, x2, y2); |
| 1410 | if (0 == denom) { |
| 1411 | return false; |
| 1412 | } |
| 1413 | a1 = SkFractDiv(x0 - x1 - SkMulDiv(y0 - y1, x2, y2), denom); |
| 1414 | } |
| 1415 | |
| 1416 | /* check if abs(x1) > abs(y1) */ |
| 1417 | if ( x1 > 0 ? y1 > 0 ? x1 > y1 : x1 > -y1 : y1 > 0 ? -x1 > y1 : x1 < y1) { |
| 1418 | SkFixed denom = y2 - SkMulDiv(x2, y1, x1); |
| 1419 | if (0 == denom) { |
| 1420 | return false; |
| 1421 | } |
| 1422 | a2 = SkFractDiv(y0 - y2 - SkMulDiv(x0 - x2, y1, x1), denom); |
| 1423 | } else { |
| 1424 | SkFixed denom = SkMulDiv(y2, x1, y1) - x2; |
| 1425 | if (0 == denom) { |
| 1426 | return false; |
| 1427 | } |
| 1428 | a2 = SkFractDiv(SkMulDiv(y0 - y2, x1, y1) - x0 + x2, denom); |
| 1429 | } |
| 1430 | |
| 1431 | // need to check if SkFixedDiv overflows... |
| 1432 | dst->fMat[kMScaleX] = SkFixedDiv(SkFractMul(a2, srcPt[3].fX) + |
| 1433 | srcPt[3].fX - srcPt[0].fX, scale.fX); |
| 1434 | dst->fMat[kMSkewY] = SkFixedDiv(SkFractMul(a2, srcPt[3].fY) + |
| 1435 | srcPt[3].fY - srcPt[0].fY, scale.fX); |
| 1436 | dst->fMat[kMPersp0] = SkFixedDiv(a2, scale.fX); |
| 1437 | dst->fMat[kMSkewX] = SkFixedDiv(SkFractMul(a1, srcPt[1].fX) + |
| 1438 | srcPt[1].fX - srcPt[0].fX, scale.fY); |
| 1439 | dst->fMat[kMScaleY] = SkFixedDiv(SkFractMul(a1, srcPt[1].fY) + |
| 1440 | srcPt[1].fY - srcPt[0].fY, scale.fY); |
| 1441 | dst->fMat[kMPersp1] = SkFixedDiv(a1, scale.fY); |
| 1442 | dst->fMat[kMTransX] = srcPt[0].fX; |
| 1443 | dst->fMat[kMTransY] = srcPt[0].fY; |
| 1444 | dst->fMat[kMPersp2] = SK_Fract1; |
| 1445 | dst->setTypeMask(kUnknown_Mask); |
| 1446 | return true; |
| 1447 | } |
| 1448 | |
| 1449 | #else /* Scalar is float */ |
| 1450 | |
| 1451 | static inline bool checkForZero(float x) { |
| 1452 | return x*x == 0; |
| 1453 | } |
| 1454 | |
| 1455 | static inline bool poly_to_point(SkPoint* pt, const SkPoint poly[], int count) { |
| 1456 | float x = 1, y = 1; |
| 1457 | SkPoint pt1, pt2; |
| 1458 | |
| 1459 | if (count > 1) { |
| 1460 | pt1.fX = poly[1].fX - poly[0].fX; |
| 1461 | pt1.fY = poly[1].fY - poly[0].fY; |
| 1462 | y = SkPoint::Length(pt1.fX, pt1.fY); |
| 1463 | if (checkForZero(y)) { |
| 1464 | return false; |
| 1465 | } |
| 1466 | switch (count) { |
| 1467 | case 2: |
| 1468 | break; |
| 1469 | case 3: |
| 1470 | pt2.fX = poly[0].fY - poly[2].fY; |
| 1471 | pt2.fY = poly[2].fX - poly[0].fX; |
| 1472 | goto CALC_X; |
| 1473 | default: |
| 1474 | pt2.fX = poly[0].fY - poly[3].fY; |
| 1475 | pt2.fY = poly[3].fX - poly[0].fX; |
| 1476 | CALC_X: |
| 1477 | x = SkScalarDiv(SkScalarMul(pt1.fX, pt2.fX) + |
| 1478 | SkScalarMul(pt1.fY, pt2.fY), y); |
| 1479 | break; |
| 1480 | } |
| 1481 | } |
| 1482 | pt->set(x, y); |
| 1483 | return true; |
| 1484 | } |
| 1485 | |
| 1486 | bool SkMatrix::Poly2Proc(const SkPoint srcPt[], SkMatrix* dst, |
| 1487 | const SkPoint& scale) { |
| 1488 | float invScale = 1 / scale.fY; |
| 1489 | |
| 1490 | dst->fMat[kMScaleX] = (srcPt[1].fY - srcPt[0].fY) * invScale; |
| 1491 | dst->fMat[kMSkewY] = (srcPt[0].fX - srcPt[1].fX) * invScale; |
| 1492 | dst->fMat[kMPersp0] = 0; |
| 1493 | dst->fMat[kMSkewX] = (srcPt[1].fX - srcPt[0].fX) * invScale; |
| 1494 | dst->fMat[kMScaleY] = (srcPt[1].fY - srcPt[0].fY) * invScale; |
| 1495 | dst->fMat[kMPersp1] = 0; |
| 1496 | dst->fMat[kMTransX] = srcPt[0].fX; |
| 1497 | dst->fMat[kMTransY] = srcPt[0].fY; |
| 1498 | dst->fMat[kMPersp2] = 1; |
| 1499 | dst->setTypeMask(kUnknown_Mask); |
| 1500 | return true; |
| 1501 | } |
| 1502 | |
| 1503 | bool SkMatrix::Poly3Proc(const SkPoint srcPt[], SkMatrix* dst, |
| 1504 | const SkPoint& scale) { |
| 1505 | float invScale = 1 / scale.fX; |
| 1506 | dst->fMat[kMScaleX] = (srcPt[2].fX - srcPt[0].fX) * invScale; |
| 1507 | dst->fMat[kMSkewY] = (srcPt[2].fY - srcPt[0].fY) * invScale; |
| 1508 | dst->fMat[kMPersp0] = 0; |
| 1509 | |
| 1510 | invScale = 1 / scale.fY; |
| 1511 | dst->fMat[kMSkewX] = (srcPt[1].fX - srcPt[0].fX) * invScale; |
| 1512 | dst->fMat[kMScaleY] = (srcPt[1].fY - srcPt[0].fY) * invScale; |
| 1513 | dst->fMat[kMPersp1] = 0; |
| 1514 | |
| 1515 | dst->fMat[kMTransX] = srcPt[0].fX; |
| 1516 | dst->fMat[kMTransY] = srcPt[0].fY; |
| 1517 | dst->fMat[kMPersp2] = 1; |
| 1518 | dst->setTypeMask(kUnknown_Mask); |
| 1519 | return true; |
| 1520 | } |
| 1521 | |
| 1522 | bool SkMatrix::Poly4Proc(const SkPoint srcPt[], SkMatrix* dst, |
| 1523 | const SkPoint& scale) { |
| 1524 | float a1, a2; |
| 1525 | float x0, y0, x1, y1, x2, y2; |
| 1526 | |
| 1527 | x0 = srcPt[2].fX - srcPt[0].fX; |
| 1528 | y0 = srcPt[2].fY - srcPt[0].fY; |
| 1529 | x1 = srcPt[2].fX - srcPt[1].fX; |
| 1530 | y1 = srcPt[2].fY - srcPt[1].fY; |
| 1531 | x2 = srcPt[2].fX - srcPt[3].fX; |
| 1532 | y2 = srcPt[2].fY - srcPt[3].fY; |
| 1533 | |
| 1534 | /* check if abs(x2) > abs(y2) */ |
| 1535 | if ( x2 > 0 ? y2 > 0 ? x2 > y2 : x2 > -y2 : y2 > 0 ? -x2 > y2 : x2 < y2) { |
| 1536 | float denom = SkScalarMulDiv(x1, y2, x2) - y1; |
| 1537 | if (checkForZero(denom)) { |
| 1538 | return false; |
| 1539 | } |
| 1540 | a1 = SkScalarDiv(SkScalarMulDiv(x0 - x1, y2, x2) - y0 + y1, denom); |
| 1541 | } else { |
| 1542 | float denom = x1 - SkScalarMulDiv(y1, x2, y2); |
| 1543 | if (checkForZero(denom)) { |
| 1544 | return false; |
| 1545 | } |
| 1546 | a1 = SkScalarDiv(x0 - x1 - SkScalarMulDiv(y0 - y1, x2, y2), denom); |
| 1547 | } |
| 1548 | |
| 1549 | /* check if abs(x1) > abs(y1) */ |
| 1550 | if ( x1 > 0 ? y1 > 0 ? x1 > y1 : x1 > -y1 : y1 > 0 ? -x1 > y1 : x1 < y1) { |
| 1551 | float denom = y2 - SkScalarMulDiv(x2, y1, x1); |
| 1552 | if (checkForZero(denom)) { |
| 1553 | return false; |
| 1554 | } |
| 1555 | a2 = SkScalarDiv(y0 - y2 - SkScalarMulDiv(x0 - x2, y1, x1), denom); |
| 1556 | } else { |
| 1557 | float denom = SkScalarMulDiv(y2, x1, y1) - x2; |
| 1558 | if (checkForZero(denom)) { |
| 1559 | return false; |
| 1560 | } |
| 1561 | a2 = SkScalarDiv(SkScalarMulDiv(y0 - y2, x1, y1) - x0 + x2, denom); |
| 1562 | } |
| 1563 | |
| 1564 | float invScale = 1 / scale.fX; |
| 1565 | dst->fMat[kMScaleX] = SkScalarMul(SkScalarMul(a2, srcPt[3].fX) + |
| 1566 | srcPt[3].fX - srcPt[0].fX, invScale); |
| 1567 | dst->fMat[kMSkewY] = SkScalarMul(SkScalarMul(a2, srcPt[3].fY) + |
| 1568 | srcPt[3].fY - srcPt[0].fY, invScale); |
| 1569 | dst->fMat[kMPersp0] = SkScalarMul(a2, invScale); |
| 1570 | invScale = 1 / scale.fY; |
| 1571 | dst->fMat[kMSkewX] = SkScalarMul(SkScalarMul(a1, srcPt[1].fX) + |
| 1572 | srcPt[1].fX - srcPt[0].fX, invScale); |
| 1573 | dst->fMat[kMScaleY] = SkScalarMul(SkScalarMul(a1, srcPt[1].fY) + |
| 1574 | srcPt[1].fY - srcPt[0].fY, invScale); |
| 1575 | dst->fMat[kMPersp1] = SkScalarMul(a1, invScale); |
| 1576 | dst->fMat[kMTransX] = srcPt[0].fX; |
| 1577 | dst->fMat[kMTransY] = srcPt[0].fY; |
| 1578 | dst->fMat[kMPersp2] = 1; |
| 1579 | dst->setTypeMask(kUnknown_Mask); |
| 1580 | return true; |
| 1581 | } |
| 1582 | |
| 1583 | #endif |
| 1584 | |
| 1585 | typedef bool (*PolyMapProc)(const SkPoint[], SkMatrix*, const SkPoint&); |
| 1586 | |
| 1587 | /* Taken from Rob Johnson's original sample code in QuickDraw GX |
| 1588 | */ |
| 1589 | bool SkMatrix::setPolyToPoly(const SkPoint src[], const SkPoint dst[], |
| 1590 | int count) { |
| 1591 | if ((unsigned)count > 4) { |
| 1592 | SkDebugf("--- SkMatrix::setPolyToPoly count out of range %d\n", count); |
| 1593 | return false; |
| 1594 | } |
| 1595 | |
| 1596 | if (0 == count) { |
| 1597 | this->reset(); |
| 1598 | return true; |
| 1599 | } |
| 1600 | if (1 == count) { |
| 1601 | this->setTranslate(dst[0].fX - src[0].fX, dst[0].fY - src[0].fY); |
| 1602 | return true; |
| 1603 | } |
| 1604 | |
| 1605 | SkPoint scale; |
| 1606 | if (!poly_to_point(&scale, src, count) || |
| 1607 | SkScalarNearlyZero(scale.fX) || |
| 1608 | SkScalarNearlyZero(scale.fY)) { |
| 1609 | return false; |
| 1610 | } |
| 1611 | |
| 1612 | static const PolyMapProc gPolyMapProcs[] = { |
| 1613 | SkMatrix::Poly2Proc, SkMatrix::Poly3Proc, SkMatrix::Poly4Proc |
| 1614 | }; |
| 1615 | PolyMapProc proc = gPolyMapProcs[count - 2]; |
| 1616 | |
| 1617 | SkMatrix tempMap, result; |
| 1618 | tempMap.setTypeMask(kUnknown_Mask); |
| 1619 | |
| 1620 | if (!proc(src, &tempMap, scale)) { |
| 1621 | return false; |
| 1622 | } |
| 1623 | if (!tempMap.invert(&result)) { |
| 1624 | return false; |
| 1625 | } |
| 1626 | if (!proc(dst, &tempMap, scale)) { |
| 1627 | return false; |
| 1628 | } |
| 1629 | if (!result.setConcat(tempMap, result)) { |
| 1630 | return false; |
| 1631 | } |
| 1632 | *this = result; |
| 1633 | return true; |
| 1634 | } |
| 1635 | |
| 1636 | /////////////////////////////////////////////////////////////////////////////// |
| 1637 | |
bsalomon@google.com | cc4dac3 | 2011-05-10 13:52:42 +0000 | [diff] [blame] | 1638 | SkScalar SkMatrix::getMaxStretch() const { |
| 1639 | TypeMask mask = this->getType(); |
| 1640 | |
| 1641 | if (mask & kPerspective_Mask) { |
| 1642 | return -SK_Scalar1; |
| 1643 | } |
| 1644 | |
| 1645 | SkScalar stretch; |
| 1646 | |
| 1647 | if (this->isIdentity()) { |
| 1648 | stretch = SK_Scalar1; |
| 1649 | } else if (!(mask & kAffine_Mask)) { |
| 1650 | stretch = SkMaxScalar(SkScalarAbs(fMat[kMScaleX]), SkScalarAbs(fMat[kMScaleY])); |
| 1651 | #if 0 // don't have this bit |
| 1652 | } else if (mask & kZeroScale_TypeBit) { |
| 1653 | stretch = SkMaxScalar(SkScalarAbs(fM[kSkewX]), SkScalarAbs(fM[kSkewY])); |
| 1654 | #endif |
| 1655 | } else { |
| 1656 | // ignore the translation part of the matrix, just look at 2x2 portion. |
| 1657 | // compute singular values, take largest abs value. |
| 1658 | // [a b; b c] = A^T*A |
| 1659 | SkScalar a = SkScalarMul(fMat[kMScaleX], fMat[kMScaleX]) + SkScalarMul(fMat[kMSkewY], fMat[kMSkewY]); |
| 1660 | SkScalar b = SkScalarMul(fMat[kMScaleX], fMat[kMSkewX]) + SkScalarMul(fMat[kMScaleY], fMat[kMSkewY]); |
| 1661 | SkScalar c = SkScalarMul(fMat[kMSkewX], fMat[kMSkewX]) + SkScalarMul(fMat[kMScaleY], fMat[kMScaleY]); |
| 1662 | // eigenvalues of A^T*A are the squared singular values of A. |
| 1663 | // characteristic equation is det((A^T*A) - l*I) = 0 |
| 1664 | // l^2 - (a + c)l + (ac-b^2) |
| 1665 | // solve using quadratic equation (divisor is non-zero since l^2 has 1 coeff |
| 1666 | // and roots are guaraunteed to be pos and real). |
| 1667 | SkScalar largerRoot; |
| 1668 | SkScalar bSqd = SkScalarMul(b,b); |
| 1669 | if (bSqd <= SkFloatToScalar(1e-10)) { // will be true if upper left 2x2 is orthogonal, which is common, so save some math |
| 1670 | largerRoot = SkMaxScalar(a, c); |
| 1671 | } else { |
| 1672 | SkScalar aminusc = a - c; |
| 1673 | SkScalar apluscdiv2 = (a + c) / 2; |
| 1674 | SkScalar x = SkScalarSqrt(SkScalarMul(aminusc, aminusc) + 4 * bSqd) / 2; |
| 1675 | largerRoot = apluscdiv2 + x; |
| 1676 | } |
| 1677 | |
| 1678 | stretch = SkScalarSqrt(largerRoot); |
| 1679 | } |
| 1680 | #if defined(SK_DEBUG) && 0 |
| 1681 | // test a bunch of vectors. None should be scaled by more than stretch |
| 1682 | // (modulo some error) and we should find a vector that is scaled by almost |
| 1683 | // stretch. |
| 1684 | SkPoint pt; |
| 1685 | SkScalar max = 0; |
| 1686 | for (int i = 0; i < 1000; ++i) { |
| 1687 | SkScalar x = (float)rand() / RAND_MAX; |
| 1688 | SkScalar y = sqrtf(1 - (x*x)); |
| 1689 | pt.fX = fMat[kMScaleX]*x + fMat[kMSkewX]*y; |
| 1690 | pt.fY = fMat[kMSkewY]*x + fMat[kMScaleY]*y; |
| 1691 | SkScalar d = pt.distanceToOrigin(); |
| 1692 | SkASSERT(d <= (1.0001 * stretch)); |
| 1693 | if (max < pt.distanceToOrigin()) { |
| 1694 | max = pt.distanceToOrigin(); |
| 1695 | } |
| 1696 | } |
| 1697 | SkASSERT((stretch - max) < .05*stretch); |
| 1698 | #endif |
| 1699 | return stretch; |
| 1700 | } |
| 1701 | |
| 1702 | const SkMatrix& SkMatrix::I() { |
| 1703 | static SkMatrix gIdentity; |
| 1704 | static bool gOnce; |
| 1705 | if (!gOnce) { |
| 1706 | gIdentity.reset(); |
| 1707 | gOnce = true; |
| 1708 | } |
| 1709 | return gIdentity; |
| 1710 | }; |
| 1711 | |
| 1712 | const SkMatrix& SkMatrix::InvalidMatrix() { |
| 1713 | static SkMatrix gInvalid; |
| 1714 | static bool gOnce; |
| 1715 | if (!gOnce) { |
| 1716 | gInvalid.setAll(SK_ScalarMax, SK_ScalarMax, SK_ScalarMax, |
| 1717 | SK_ScalarMax, SK_ScalarMax, SK_ScalarMax, |
| 1718 | SK_ScalarMax, SK_ScalarMax, SK_ScalarMax); |
| 1719 | gInvalid.getType(); // force the type to be computed |
| 1720 | gOnce = true; |
| 1721 | } |
| 1722 | return gInvalid; |
| 1723 | } |
| 1724 | |
| 1725 | /////////////////////////////////////////////////////////////////////////////// |
| 1726 | |
reed@android.com | 0ad336f | 2009-06-29 16:02:20 +0000 | [diff] [blame] | 1727 | uint32_t SkMatrix::flatten(void* buffer) const { |
| 1728 | // TODO write less for simple matrices |
| 1729 | if (buffer) { |
| 1730 | memcpy(buffer, fMat, 9 * sizeof(SkScalar)); |
| 1731 | } |
| 1732 | return 9 * sizeof(SkScalar); |
| 1733 | } |
| 1734 | |
| 1735 | uint32_t SkMatrix::unflatten(const void* buffer) { |
reed@android.com | f2b98d6 | 2010-12-20 18:26:13 +0000 | [diff] [blame] | 1736 | if (buffer) { |
| 1737 | memcpy(fMat, buffer, 9 * sizeof(SkScalar)); |
| 1738 | this->setTypeMask(kUnknown_Mask); |
| 1739 | } |
reed@android.com | 0ad336f | 2009-06-29 16:02:20 +0000 | [diff] [blame] | 1740 | return 9 * sizeof(SkScalar); |
| 1741 | } |
| 1742 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 1743 | void SkMatrix::dump() const { |
| 1744 | SkString str; |
| 1745 | this->toDumpString(&str); |
| 1746 | SkDebugf("%s\n", str.c_str()); |
| 1747 | } |
| 1748 | |
| 1749 | void SkMatrix::toDumpString(SkString* str) const { |
| 1750 | #ifdef SK_CAN_USE_FLOAT |
| 1751 | str->printf("[%8.4f %8.4f %8.4f][%8.4f %8.4f %8.4f][%8.4f %8.4f %8.4f]", |
| 1752 | #ifdef SK_SCALAR_IS_FLOAT |
| 1753 | fMat[0], fMat[1], fMat[2], fMat[3], fMat[4], fMat[5], |
| 1754 | fMat[6], fMat[7], fMat[8]); |
| 1755 | #else |
| 1756 | SkFixedToFloat(fMat[0]), SkFixedToFloat(fMat[1]), SkFixedToFloat(fMat[2]), |
| 1757 | SkFixedToFloat(fMat[3]), SkFixedToFloat(fMat[4]), SkFixedToFloat(fMat[5]), |
| 1758 | SkFractToFloat(fMat[6]), SkFractToFloat(fMat[7]), SkFractToFloat(fMat[8])); |
| 1759 | #endif |
| 1760 | #else // can't use float |
| 1761 | str->printf("[%x %x %x][%x %x %x][%x %x %x]", |
| 1762 | fMat[0], fMat[1], fMat[2], fMat[3], fMat[4], fMat[5], |
| 1763 | fMat[6], fMat[7], fMat[8]); |
| 1764 | #endif |
| 1765 | } |