caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1 | /* |
caryclark@google.com | 1304bb2 | 2013-03-13 20:29:41 +0000 | [diff] [blame] | 2 | * Copyright 2011 Google Inc. |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 3 | * |
caryclark@google.com | 1304bb2 | 2013-03-13 20:29:41 +0000 | [diff] [blame] | 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 6 | */ |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 7 | #include "SkAntiEdge.h" |
| 8 | #include "SkPoint.h" |
| 9 | |
reed@google.com | 1915fd0 | 2013-12-19 14:22:03 +0000 | [diff] [blame^] | 10 | /** Returns the signed fraction of a SkFixed |
| 11 | */ |
| 12 | static inline SkFixed SkFixedFraction(SkFixed x) |
| 13 | { |
| 14 | SkFixed mask = x >> 31 << 16; |
| 15 | return (x & 0xFFFF) | mask; |
| 16 | } |
| 17 | |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 18 | void SkAntiEdge::pointOnLine(SkFixed x, SkFixed y) { |
| 19 | float x0 = SkFixedToFloat(x); |
| 20 | float y0 = SkFixedToFloat(y); |
| 21 | float x1 = SkFixedToFloat(fFirstX); |
| 22 | float y1 = SkFixedToFloat(fFirstY); |
| 23 | float x2 = SkFixedToFloat(fLastX); |
| 24 | float y2 = SkFixedToFloat(fLastY); |
| 25 | float numer = (x2 - x1) * (y1 - y0) - (x1 - x0) * (y2 - y1); |
| 26 | float denom = (x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1); |
| 27 | double dist = fabs(numer) / sqrt(denom); |
| 28 | SkAssertResult(dist < 0.01); |
| 29 | } |
| 30 | |
| 31 | void SkAntiEdge::pointInLine(SkFixed x, SkFixed y) { |
| 32 | if (y == SK_MaxS32) { |
| 33 | return; |
| 34 | } |
| 35 | pointOnLine(x, y); |
| 36 | SkAssertResult(y >= fFirstY && y <= fLastY); |
| 37 | } |
| 38 | |
| 39 | void SkAntiEdge::validate() { |
| 40 | pointOnLine(fWalkX, fY); |
| 41 | pointOnLine(fX, fWalkY); |
| 42 | } |
| 43 | |
| 44 | bool SkAntiEdge::setLine(const SkPoint& p0, const SkPoint& p1) { |
| 45 | fFirstY = SkScalarToFixed(p0.fY); |
| 46 | fLastY = SkScalarToFixed(p1.fY); |
| 47 | if (fFirstY == fLastY) { |
| 48 | return false; |
rmistry@google.com | d6176b0 | 2012-08-23 18:14:13 +0000 | [diff] [blame] | 49 | } |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 50 | fFirstX = SkScalarToFixed(p0.fX); |
| 51 | fLastX = SkScalarToFixed(p1.fX); |
| 52 | if (fFirstY > fLastY) { |
| 53 | SkTSwap(fFirstX, fLastX); |
| 54 | SkTSwap(fFirstY, fLastY); |
| 55 | fWinding = -1; |
| 56 | } else { |
| 57 | fWinding = 1; |
| 58 | } |
| 59 | SkFixed dx = fLastX - fFirstX; |
| 60 | fDXFlipped = dx < 0; |
| 61 | SkFixed dy = fLastY - fFirstY; |
| 62 | fDX = SkFixedDiv(dx, dy); |
| 63 | fDY = dx == 0 ? SK_MaxS32 : SkFixedDiv(dy, SkFixedAbs(dx)); |
| 64 | fLink = NULL; |
| 65 | fLinkSet = false; |
| 66 | return true; |
| 67 | } |
| 68 | |
| 69 | void SkAntiEdge::calcLine() { |
| 70 | SkFixed yStartFrac = SkFixedFraction(fFirstY); |
| 71 | if (fDXFlipped) { |
| 72 | SkFixed vert = SK_Fixed1 - yStartFrac; // distance from y start to x-axis |
| 73 | fX0 = fFirstX + SkFixedMul(fDX, vert); |
| 74 | SkFixed backupX = fFirstX + SkFixedMul(vert, fDX); // x cell to back up to |
| 75 | SkFixed cellX = SkIntToFixed(SkFixedFloor(backupX)); |
| 76 | SkFixed endX = SkIntToFixed(SkFixedFloor(fLastX)); |
| 77 | if (cellX < endX) { |
| 78 | cellX = endX; |
| 79 | } |
| 80 | SkFixed distX = fFirstX - cellX; // to y-axis |
| 81 | fY0 = fFirstY + SkFixedMul(fDY, distX); |
| 82 | SkFixed rowBottom = SkIntToFixed(SkFixedCeil(fFirstY + 1)); |
| 83 | if (fLastY > rowBottom) { |
| 84 | fPartialY = 0; |
| 85 | fX = fX0; |
| 86 | fY = rowBottom; |
| 87 | } else { |
| 88 | fPartialY = SkFixedFraction(fLastY); |
| 89 | fX = fLastX; |
| 90 | fY = fLastY; |
| 91 | } |
| 92 | } else { |
| 93 | fPartialY = yStartFrac; |
| 94 | fX0 = fFirstX - SkFixedMul(fDX, yStartFrac); |
| 95 | fY0 = fFirstY; |
| 96 | if (fDY != SK_MaxS32) { |
| 97 | SkFixed xStartFrac = SkFixedFraction(fFirstX); |
| 98 | fY0 -= SkFixedMul(fDY, xStartFrac); |
| 99 | } |
| 100 | fX = fFirstX; |
| 101 | fY = fFirstY; |
| 102 | } |
| 103 | fWalkX = fX; |
| 104 | fWalkY = fY; |
| 105 | fFinished = false; |
| 106 | } |
| 107 | |
| 108 | static SkFixed SkFixedAddPin(SkFixed a, SkFixed b) { |
| 109 | SkFixed result = a + b; |
| 110 | if (((a ^ ~b) & (a ^ result)) >= 0) { // one positive, one negative |
| 111 | return result; // or all three same sign |
| 112 | } |
| 113 | return a < 0 ? -SK_FixedMax : SK_FixedMax; |
| 114 | } |
| 115 | |
| 116 | // edge is increasing in x and y |
| 117 | uint16_t SkAntiEdge::advanceX(SkFixed left) { |
| 118 | validate(); |
| 119 | SkFixed x = SkFixedAddPin(fX0, fDX); |
| 120 | SkFixed wy = SkIntToFixed(SkFixedFloor(fWalkY + SK_Fixed1)); |
| 121 | pointOnLine(x, wy); |
| 122 | SkFixed partial = SK_Fixed1 - fPartialY; |
| 123 | SkFixed bottomPartial = wy - fLastY; |
| 124 | if (bottomPartial > 0) { |
| 125 | partial -= bottomPartial; |
| 126 | } |
| 127 | if (x > fLastX) { |
| 128 | x = fLastX; |
| 129 | wy = fLastY; |
| 130 | } |
| 131 | uint16_t coverage; |
| 132 | if (left >= x) { |
| 133 | fFinished = true; |
| 134 | coverage = partial - 1; // walker is to the right of edge |
| 135 | } else { |
| 136 | SkFixed y = SkFixedAddPin(fY0, fDY); |
| 137 | SkFixed wx = SkIntToFixed(SkFixedFloor(fWalkX + SK_Fixed1)); |
| 138 | if (fDY != SK_MaxS32) { |
| 139 | pointOnLine(wx, y); |
| 140 | } |
| 141 | if (y > fLastY) { |
| 142 | y = fLastY; |
| 143 | wx = fLastX; |
| 144 | } |
| 145 | bool topCorner = fWalkX <= fX; |
| 146 | bool bottomCorner = x <= wx; |
| 147 | bool halfPlane = !(topCorner ^ bottomCorner); |
| 148 | if (halfPlane) { |
| 149 | if (x - SkIntToFixed(SkFixedFloor(fX)) <= SK_Fixed1) { |
| 150 | coverage = ~((fX + x) >> 1); // avg of fx, fx+dx |
| 151 | fFinished = true; |
| 152 | if (x >= left + SK_Fixed1) { |
| 153 | fWalkX = wx; |
| 154 | fY = fY0 = y; |
| 155 | } |
| 156 | } else { |
| 157 | SkAssertResult(y - SkIntToFixed(SkFixedFloor(fY)) <= SK_Fixed1); |
| 158 | coverage = ((fY + y) >> 1); |
| 159 | fFinished = y == fLastY; |
| 160 | fWalkX = wx; |
| 161 | fY = fY0 = y; |
| 162 | } |
| 163 | coverage = coverage * partial >> 16; |
| 164 | } else if (topCorner) { |
| 165 | SkFixed xDiff = wx - fX; |
| 166 | SkAssertResult(xDiff >= 0); |
| 167 | SkAssertResult(xDiff <= SK_Fixed1); |
| 168 | SkFixed yDiff = y - fWalkY; |
| 169 | // This may be a very small negative number if error accumulates |
| 170 | // FIXME: for now, try setting it to zero in that case. |
| 171 | if (yDiff < 0) { |
| 172 | fX = fX0 = SkIntToFixed(SkFixedCeil(fX)); |
| 173 | yDiff = 0; |
| 174 | } |
| 175 | SkAssertResult(yDiff >= 0); |
| 176 | SkAssertResult(yDiff <= SK_Fixed1); |
| 177 | int xCoverage = xDiff >> 1; // throw away 1 bit so multiply |
| 178 | int yCoverage = yDiff >> 1; // stays in range |
| 179 | int triangle = xCoverage * yCoverage; // 30 bits |
| 180 | SkFixed bottomPartial = y - fLastY; |
| 181 | fFinished = bottomPartial >= 0; |
| 182 | if (fFinished) { |
| 183 | yCoverage = bottomPartial >> 1; |
| 184 | xCoverage = (wx - fLastX) >> 1; |
| 185 | triangle -= xCoverage * yCoverage; |
| 186 | } |
| 187 | coverage = triangle >> 15; |
| 188 | fWalkX = wx; |
| 189 | fY = fY0 = y; |
| 190 | } else { |
| 191 | SkAssertResult(bottomCorner); |
| 192 | SkFixed xDiff = x - fWalkX; |
| 193 | SkAssertResult(xDiff >= 0); |
| 194 | SkAssertResult(xDiff <= SK_Fixed1); |
| 195 | SkFixed yDiff = wy - fY; |
| 196 | SkAssertResult(yDiff >= 0); |
| 197 | SkAssertResult(yDiff <= SK_Fixed1); |
rmistry@google.com | d6176b0 | 2012-08-23 18:14:13 +0000 | [diff] [blame] | 198 | int xCoverage = xDiff >> 1; // throw away 1 bit so multiply |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 199 | int yCoverage = yDiff >> 1; // stays in range |
| 200 | int triangle = xCoverage * yCoverage >> 15; |
| 201 | coverage = partial - 1 - triangle; |
| 202 | fFinished = true; |
| 203 | } |
| 204 | } |
| 205 | validate(); |
| 206 | return coverage; |
| 207 | } |
| 208 | |
| 209 | // edge is increasing in x, but decreasing in y |
| 210 | uint16_t SkAntiEdge::advanceFlippedX(SkFixed left) { |
| 211 | validate(); |
| 212 | SkFixed x = SkFixedAddPin(fX0, -fDX); |
| 213 | SkFixed wy = SkIntToFixed(SkFixedFloor(fWalkY - 1)); |
| 214 | pointOnLine(x, wy); |
| 215 | SkFixed partial = fPartialY ? fPartialY : SK_Fixed1; |
| 216 | SkFixed topPartial = fFirstY - wy; |
| 217 | if (topPartial > 0) { |
| 218 | partial -= topPartial; |
| 219 | } |
| 220 | if (x > fFirstX) { |
| 221 | x = fFirstX; |
| 222 | wy = fFirstY; |
| 223 | } |
| 224 | uint16_t coverage; |
| 225 | if (left >= x) { |
| 226 | fFinished = true; |
| 227 | coverage = partial - 1; // walker is to the right of edge |
| 228 | } else { |
| 229 | SkFixed y = SkFixedAddPin(fY0, -fDY); |
| 230 | SkFixed wx = SkIntToFixed(SkFixedFloor(fWalkX + SK_Fixed1)); |
| 231 | pointOnLine(wx, y); |
| 232 | if (y < fFirstY) { |
| 233 | y = fFirstY; |
| 234 | wx = fFirstX; |
| 235 | } |
| 236 | bool bottomCorner = fWalkX <= fX; |
| 237 | bool topCorner = x <= wx; |
| 238 | bool halfPlane = !(topCorner ^ bottomCorner); |
| 239 | if (halfPlane) { |
| 240 | if (x - SkIntToFixed(SkFixedFloor(fX)) <= SK_Fixed1) { |
| 241 | coverage = ~((fX + x) >> 1); // avg of fx, fx+dx |
| 242 | fFinished = true; |
| 243 | } else { |
| 244 | SkAssertResult(y - SkIntToFixed(SkFixedFloor(fY)) <= SK_Fixed1); |
| 245 | coverage = ~((fY + y) >> 1); |
| 246 | fFinished = y == fY; |
| 247 | fWalkX = wx; |
| 248 | fY = fY0 = y; |
| 249 | } |
| 250 | coverage = coverage * partial >> 16; |
| 251 | } else if (bottomCorner) { |
| 252 | SkFixed xDiff = wx - fX; |
| 253 | SkAssertResult(xDiff >= 0); |
| 254 | SkAssertResult(xDiff <= SK_Fixed1); |
| 255 | SkFixed yDiff = fWalkY - y; |
| 256 | SkAssertResult(yDiff >= 0); |
| 257 | SkAssertResult(yDiff <= SK_Fixed1); |
| 258 | int xCoverage = xDiff >> 1; // throw away 1 bit so multiply |
| 259 | int yCoverage = yDiff >> 1; // stays in range |
| 260 | int triangle = xCoverage * yCoverage; // 30 bits |
| 261 | SkFixed bottomPartial = fFirstY - y; |
| 262 | fFinished = bottomPartial >= 0; |
| 263 | if (fFinished) { |
| 264 | yCoverage = bottomPartial >> 1; |
| 265 | xCoverage = (wx - fFirstX) >> 1; |
| 266 | triangle -= xCoverage * yCoverage; |
| 267 | } |
| 268 | coverage = triangle >> 15; |
| 269 | fWalkX = wx; |
| 270 | fY = fY0 = y; |
| 271 | } else { |
| 272 | SkAssertResult(topCorner); |
| 273 | SkFixed xDiff = x - fWalkX; |
| 274 | SkAssertResult(xDiff >= 0); |
| 275 | SkAssertResult(xDiff <= SK_Fixed1); |
| 276 | SkFixed yDiff = fY - wy; |
| 277 | SkAssertResult(yDiff >= 0); |
| 278 | SkAssertResult(yDiff <= SK_Fixed1); |
rmistry@google.com | d6176b0 | 2012-08-23 18:14:13 +0000 | [diff] [blame] | 279 | int xCoverage = xDiff >> 1; // throw away 1 bit so multiply |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 280 | int yCoverage = yDiff >> 1; // stays in range |
| 281 | int triangle = xCoverage * yCoverage >> 15; |
| 282 | coverage = partial - 1 - triangle; |
| 283 | fFinished = true; |
| 284 | } |
| 285 | } |
| 286 | validate(); |
| 287 | return coverage; |
| 288 | } |
| 289 | |
| 290 | void SkAntiEdge::advanceY(SkFixed top) { |
| 291 | validate(); |
| 292 | fX0 = SkFixedAddPin(fX0, fDX); |
| 293 | fPartialY = 0; |
| 294 | if (fDXFlipped) { |
| 295 | if (fX0 < fLastX) { |
| 296 | fWalkX = fX = fLastX; |
| 297 | } else { |
| 298 | fWalkX = fX = fX0; |
| 299 | } |
| 300 | SkFixed bottom = top + SK_Fixed1; |
| 301 | if (bottom > fLastY) { |
| 302 | bottom = fLastY; |
| 303 | } |
| 304 | SkFixed vert = bottom - fFirstY; // distance from y start to x-axis |
| 305 | SkFixed backupX = fFirstX + SkFixedMul(vert, fDX); // x cell to back up to |
| 306 | SkFixed distX = fFirstX - SkIntToFixed(SkFixedFloor(backupX)); // to y-axis |
| 307 | fY0 = fFirstY + SkFixedMul(fDY, distX); |
| 308 | |
| 309 | fY = top + SK_Fixed1; |
| 310 | if (fY > fLastY) { |
| 311 | fY = fLastY; |
| 312 | } |
| 313 | if (fLastY < top + SK_Fixed1) { |
| 314 | fPartialY = SkFixedFraction(fLastY); |
| 315 | } |
| 316 | } else { |
| 317 | if (fX0 > fLastX) { |
| 318 | fX0 = fLastX; |
| 319 | } |
| 320 | fX = fX0; |
| 321 | } |
| 322 | fWalkY = SkIntToFixed(SkFixedFloor(fWalkY + SK_Fixed1)); |
| 323 | if (fWalkY > fLastY) { |
| 324 | fWalkY = fLastY; |
| 325 | } |
| 326 | validate(); |
| 327 | fFinished = false; |
| 328 | } |
| 329 | |
| 330 | int SkAntiEdgeBuilder::build(const SkPoint pts[], int count) { |
| 331 | SkAntiEdge* edge = fEdges.append(); |
| 332 | for (int index = 0; index < count; ++index) { |
| 333 | if (edge->setLine(pts[index], pts[(index + 1) % count])) { |
| 334 | edge = fEdges.append(); |
| 335 | } |
| 336 | } |
| 337 | int result = fEdges.count(); |
| 338 | fEdges.setCount(--result); |
| 339 | if (result > 0) { |
| 340 | sk_bzero(&fHeadEdge, sizeof(fHeadEdge)); |
| 341 | sk_bzero(&fTailEdge, sizeof(fTailEdge)); |
| 342 | for (int index = 0; index < result; ++index) { |
| 343 | *fList.append() = &fEdges[index]; |
| 344 | } |
| 345 | } |
| 346 | return result; |
| 347 | } |
| 348 | |
| 349 | void SkAntiEdgeBuilder::calc() { |
| 350 | for (SkAntiEdge* active = fEdges.begin(); active != fEdges.end(); ++active) { |
| 351 | active->calcLine(); |
| 352 | } |
| 353 | // compute winding sum for edges |
| 354 | SkAntiEdge* first = fHeadEdge.fNext; |
| 355 | SkAntiEdge* active; |
| 356 | SkAntiEdge* listTop = first; |
| 357 | for (active = first; active != &fTailEdge; active = active->fNext) { |
| 358 | active->fWindingSum = active->fWinding; |
| 359 | while (listTop->fLastY < active->fFirstY) { |
| 360 | listTop = listTop->fNext; |
| 361 | } |
| 362 | for (SkAntiEdge* check = listTop; check->fFirstY <= active->fFirstY; check = check->fNext) { |
| 363 | if (check == active) { |
| 364 | continue; |
| 365 | } |
| 366 | if (check->fLastY <= active->fFirstY) { |
| 367 | continue; |
| 368 | } |
| 369 | if (check->fFirstX > active->fFirstX) { |
| 370 | continue; |
| 371 | } |
| 372 | if (check->fFirstX == active->fFirstX && check->fDX > active->fDX) { |
| 373 | continue; |
| 374 | } |
| 375 | active->fWindingSum += check->fWinding; |
| 376 | } |
| 377 | } |
| 378 | } |
| 379 | |
| 380 | extern "C" { |
| 381 | static int edge_compare(const void* a, const void* b) { |
| 382 | const SkAntiEdge* edgea = *(const SkAntiEdge**)a; |
| 383 | const SkAntiEdge* edgeb = *(const SkAntiEdge**)b; |
| 384 | |
| 385 | int valuea = edgea->fFirstY; |
| 386 | int valueb = edgeb->fFirstY; |
| 387 | |
| 388 | if (valuea == valueb) { |
| 389 | valuea = edgea->fFirstX; |
| 390 | valueb = edgeb->fFirstX; |
| 391 | } |
rmistry@google.com | d6176b0 | 2012-08-23 18:14:13 +0000 | [diff] [blame] | 392 | |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 393 | if (valuea == valueb) { |
| 394 | valuea = edgea->fDX; |
| 395 | valueb = edgeb->fDX; |
| 396 | } |
| 397 | |
| 398 | return valuea - valueb; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | void SkAntiEdgeBuilder::sort(SkTDArray<SkAntiEdge*>& listOfEdges) { |
| 403 | SkAntiEdge** list = listOfEdges.begin(); |
| 404 | int count = listOfEdges.count(); |
| 405 | qsort(list, count, sizeof(SkAntiEdge*), edge_compare); |
| 406 | |
| 407 | // link the edges in sorted order |
| 408 | for (int i = 1; i < count; i++) { |
| 409 | list[i - 1]->fNext = list[i]; |
| 410 | list[i]->fPrev = list[i - 1]; |
| 411 | } |
| 412 | } |
| 413 | |
| 414 | #define kEDGE_HEAD_XY SK_MinS32 |
| 415 | #define kEDGE_TAIL_XY SK_MaxS32 |
| 416 | |
| 417 | void SkAntiEdgeBuilder::sort() { |
| 418 | sort(fList); |
| 419 | SkAntiEdge* last = fList.end()[-1]; |
| 420 | fHeadEdge.fNext = fList[0]; |
| 421 | fHeadEdge.fFirstX = fHeadEdge.fFirstY = fHeadEdge.fWalkY = fHeadEdge.fLastY = kEDGE_HEAD_XY; |
| 422 | fList[0]->fPrev = &fHeadEdge; |
| 423 | |
| 424 | fTailEdge.fPrev = last; |
| 425 | fTailEdge.fFirstX = fTailEdge.fFirstY = fTailEdge.fWalkY = fTailEdge.fLastY = kEDGE_TAIL_XY; |
| 426 | last->fNext = &fTailEdge; |
| 427 | } |
| 428 | |
| 429 | static inline void remove_edge(SkAntiEdge* edge) { |
| 430 | edge->fPrev->fNext = edge->fNext; |
| 431 | edge->fNext->fPrev = edge->fPrev; |
| 432 | } |
| 433 | |
| 434 | static inline void swap_edges(SkAntiEdge* prev, SkAntiEdge* next) { |
| 435 | SkASSERT(prev->fNext == next && next->fPrev == prev); |
| 436 | |
| 437 | // remove prev from the list |
| 438 | prev->fPrev->fNext = next; |
| 439 | next->fPrev = prev->fPrev; |
| 440 | |
| 441 | // insert prev after next |
| 442 | prev->fNext = next->fNext; |
| 443 | next->fNext->fPrev = prev; |
| 444 | next->fNext = prev; |
| 445 | prev->fPrev = next; |
| 446 | } |
| 447 | |
| 448 | static void backward_insert_edge_based_on_x(SkAntiEdge* edge SkDECLAREPARAM(int, y)) { |
| 449 | SkFixed x = edge->fFirstX; |
| 450 | |
| 451 | for (;;) { |
| 452 | SkAntiEdge* prev = edge->fPrev; |
| 453 | |
| 454 | // add 1 to curr_y since we may have added new edges (built from curves) |
| 455 | // that start on the next scanline |
| 456 | SkASSERT(prev && SkFixedFloor(prev->fWalkY - prev->fDXFlipped) <= y + 1); |
| 457 | |
| 458 | if (prev->fFirstX <= x) { |
| 459 | break; |
| 460 | } |
| 461 | swap_edges(prev, edge); |
| 462 | } |
| 463 | } |
| 464 | |
| 465 | static void insert_new_edges(SkAntiEdge* newEdge, SkFixed curr_y) { |
| 466 | int y = SkFixedFloor(curr_y); |
| 467 | if (SkFixedFloor(newEdge->fWalkY - newEdge->fDXFlipped) < y) { |
| 468 | return; |
| 469 | } |
| 470 | while (SkFixedFloor(newEdge->fWalkY - newEdge->fDXFlipped) == y) { |
| 471 | SkAntiEdge* next = newEdge->fNext; |
| 472 | backward_insert_edge_based_on_x(newEdge SkPARAM(y)); |
| 473 | newEdge = next; |
| 474 | } |
| 475 | } |
| 476 | |
| 477 | static int find_active_edges(int y, SkAntiEdge** activeLeft, |
| 478 | SkAntiEdge** activeLast) { |
| 479 | SkAntiEdge* first = *activeLeft; |
| 480 | SkFixed bottom = first->fLastY; |
| 481 | SkAntiEdge* active = first->fNext; |
| 482 | first->fLinkSet = false; |
| 483 | SkFixed yLimit = SkIntToFixed(y + 1); // limiting pixel edge |
| 484 | for ( ; active->fWalkY != kEDGE_TAIL_XY; active = active->fNext) { |
| 485 | active->fLinkSet = false; |
| 486 | if (yLimit <= active->fWalkY - active->fDXFlipped) { |
| 487 | break; |
| 488 | } |
| 489 | if ((*activeLeft)->fWalkX > active->fWalkX) { |
| 490 | *activeLeft = active; |
| 491 | } |
| 492 | if (bottom > active->fLastY) { |
| 493 | bottom = active->fLastY; |
| 494 | } |
| 495 | } |
| 496 | *activeLast = active; |
| 497 | return SkFixedCeil(bottom); |
| 498 | } |
| 499 | |
| 500 | // All edges are oriented to increase in y. Link edges with common tops and |
| 501 | // bottoms so the links can share their winding sum. |
| 502 | void SkAntiEdgeBuilder::link() { |
| 503 | SkAntiEdge* tail = fEdges.end(); |
| 504 | // look for links forwards and backwards |
| 505 | SkAntiEdge* prev = fEdges.begin(); |
| 506 | SkAntiEdge* active; |
| 507 | for (active = prev + 1; active != tail; ++active) { |
| 508 | if (prev->fWinding == active->fWinding) { |
| 509 | if (prev->fLastX == active->fFirstX && prev->fLastY == active->fFirstY) { |
| 510 | prev->fLink = active; |
| 511 | active->fLinkSet = true; |
| 512 | } else if (active->fLastX == prev->fFirstX && active->fLastY == prev->fFirstY) { |
| 513 | active->fLink = prev; |
| 514 | prev->fLinkSet = true; |
| 515 | } |
| 516 | } |
| 517 | prev = active; |
| 518 | } |
| 519 | // look for stragglers |
| 520 | prev = fEdges.begin() - 1; |
| 521 | do { |
| 522 | do { |
| 523 | if (++prev == tail) { |
| 524 | return; |
| 525 | } |
| 526 | } while (prev->fLinkSet || NULL != prev->fLink); |
| 527 | for (active = prev + 1; active != tail; ++active) { |
| 528 | if (active->fLinkSet || NULL != active->fLink) { |
| 529 | continue; |
| 530 | } |
| 531 | if (prev->fWinding != active->fWinding) { |
| 532 | continue; |
| 533 | } |
| 534 | if (prev->fLastX == active->fFirstX && prev->fLastY == active->fFirstY) { |
| 535 | prev->fLink = active; |
| 536 | active->fLinkSet = true; |
| 537 | break; |
| 538 | } |
| 539 | if (active->fLastX == prev->fFirstX && active->fLastY == prev->fFirstY) { |
| 540 | active->fLink = prev; |
| 541 | prev->fLinkSet = true; |
| 542 | break; |
| 543 | } |
| 544 | } |
| 545 | } while (true); |
| 546 | } |
| 547 | |
| 548 | void SkAntiEdgeBuilder::split(SkAntiEdge* edge, SkFixed y) { |
| 549 | SkPoint upperPoint = {edge->fFirstX, edge->fFirstY}; |
| 550 | SkPoint midPoint = {edge->fFirstX + SkMulDiv(y - edge->fFirstY, |
| 551 | edge->fLastX - edge->fFirstX, edge->fLastY - edge->fFirstY), y}; |
| 552 | SkPoint lowerPoint = {edge->fLastX, edge->fLastY}; |
| 553 | int8_t winding = edge->fWinding; |
| 554 | edge->setLine(upperPoint, midPoint); |
| 555 | edge->fWinding = winding; |
| 556 | SkAntiEdge* lower = fEdges.append(); |
| 557 | lower->setLine(midPoint, lowerPoint); |
| 558 | lower->fWinding = winding; |
| 559 | insert_new_edges(lower, y); |
| 560 | } |
| 561 | |
| 562 | // An edge computes pixel coverage by considering the integral winding value |
| 563 | // to its left. If an edge is enclosed by fractional winding, split it. |
| 564 | // FIXME: This is also a good time to find crossing edges and split them, too. |
| 565 | void SkAntiEdgeBuilder::split() { |
| 566 | // create a new set of edges that describe the whole link |
| 567 | SkTDArray<SkAntiEdge> links; |
| 568 | SkAntiEdge* first = fHeadEdge.fNext; |
| 569 | SkAntiEdge* active; |
| 570 | for (active = first; active != &fTailEdge; active = active->fNext) { |
| 571 | if (active->fLinkSet || NULL == active->fLink) { |
| 572 | continue; |
| 573 | } |
| 574 | SkAntiEdge* link = links.append(); |
| 575 | link->fFirstX = active->fFirstX; |
| 576 | link->fFirstY = active->fFirstY; |
| 577 | SkAntiEdge* linkEnd; |
| 578 | SkAntiEdge* next = active; |
| 579 | do { |
| 580 | linkEnd = next; |
| 581 | next = next->fLink; |
| 582 | } while (NULL != next); |
| 583 | link->fLastX = linkEnd->fLastX; |
| 584 | link->fLastY = linkEnd->fLastY; |
| 585 | } |
| 586 | // create a list of all edges, links and singletons |
| 587 | SkTDArray<SkAntiEdge*> list; |
| 588 | for (active = links.begin(); active != links.end(); ++active) { |
| 589 | *list.append() = active; |
| 590 | } |
| 591 | for (active = first; active != &fTailEdge; active = active->fNext) { |
| 592 | if (!active->fLinkSet && NULL == active->fLink) { |
| 593 | SkAntiEdge* link = links.append(); |
| 594 | link->fFirstX = active->fFirstX; |
| 595 | link->fFirstY = active->fFirstY; |
| 596 | link->fLastX = active->fLastX; |
| 597 | link->fLastY = active->fLastY; |
| 598 | *list.append() = link; |
| 599 | } |
| 600 | } |
| 601 | SkAntiEdge tail; |
| 602 | tail.fFirstY = tail.fLastY = kEDGE_TAIL_XY; |
| 603 | *list.append() = &tail; |
| 604 | sort(list); |
| 605 | // walk the list, splitting edges partially occluded on the left |
| 606 | SkAntiEdge* listTop = list[0]; |
| 607 | for (active = first; active != &fTailEdge; active = active->fNext) { |
| 608 | while (listTop->fLastY < active->fFirstY) { |
| 609 | listTop = listTop->fNext; |
| 610 | } |
| 611 | for (SkAntiEdge* check = listTop; check->fFirstY < active->fLastY; check = check->fNext) { |
| 612 | if (check->fFirstX > active->fFirstX) { |
| 613 | continue; |
| 614 | } |
| 615 | if (check->fFirstX == active->fFirstX && check->fDX > active->fDX) { |
| 616 | continue; |
| 617 | } |
| 618 | if (check->fFirstY > active->fFirstY) { |
| 619 | split(active, check->fFirstY); |
| 620 | } |
| 621 | if (check->fLastY < active->fLastY) { |
| 622 | split(active, check->fLastY); |
| 623 | } |
| 624 | } |
| 625 | } |
| 626 | } |
| 627 | |
| 628 | static inline uint8_t coverage_to_8(int coverage) { |
| 629 | uint16_t x = coverage < 0 ? 0 : coverage > 0xFFFF ? 0xFFFF : coverage; |
| 630 | // for values 0x7FFF and smaller, add (0x7F - high byte) and trunc |
| 631 | // for values 0x8000 and larger, subtract (high byte - 0x80) and trunc |
| 632 | return (x + 0x7f + (x >> 15) - (x >> 8)) >> 8; |
| 633 | } |
| 634 | |
| 635 | void SkAntiEdgeBuilder::walk(uint8_t* result, int rowBytes, int height) { |
| 636 | SkAntiEdge* first = fHeadEdge.fNext; |
| 637 | SkFixed top = first->fWalkY - first->fDXFlipped; |
| 638 | int y = SkFixedFloor(top); |
| 639 | do { |
| 640 | SkAntiEdge* activeLeft = first; |
| 641 | SkAntiEdge* activeLast, * active; |
| 642 | int yLast = find_active_edges(y, &activeLeft, &activeLast); |
| 643 | while (y < yLast) { |
| 644 | SkAssertResult(y >= 0); |
| 645 | SkAssertResult(y < height); |
| 646 | SkFixed left = activeLeft->fWalkX; |
| 647 | int x = SkFixedFloor(left); |
| 648 | uint8_t* resultPtr = &result[y * rowBytes + x]; |
| 649 | bool finished; |
| 650 | do { |
| 651 | left = SkIntToFixed(x); |
| 652 | SkAssertResult(x >= 0); |
| 653 | // SkAssertResult(x < pixelCol); |
| 654 | if (x >= rowBytes) { // FIXME: cumulative error in fX += fDX |
| 655 | break; // fails to set fFinished early enough |
| 656 | } // see test 6 (dy<dx) |
| 657 | finished = true; |
| 658 | int coverage = 0; |
| 659 | for (active = first; active != activeLast; active = active->fNext) { |
| 660 | if (left + SK_Fixed1 <= active->fX) { |
| 661 | finished = false; |
| 662 | continue; // walker is to the left of edge |
| 663 | } |
| 664 | int cover = active->fDXFlipped ? |
| 665 | active->advanceFlippedX(left) : active->advanceX(left); |
| 666 | if (0 == active->fWindingSum) { |
| 667 | cover = -cover; |
| 668 | } |
| 669 | coverage += cover; |
| 670 | finished &= active->fFinished; |
| 671 | } |
| 672 | uint8_t old = *resultPtr; |
| 673 | uint8_t pix = coverage_to_8(coverage); |
rmistry@google.com | d6176b0 | 2012-08-23 18:14:13 +0000 | [diff] [blame] | 674 | uint8_t blend = old > pix ? old : pix; |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 675 | *resultPtr++ = blend; |
| 676 | ++x; |
| 677 | } while (!finished); |
| 678 | ++y; |
| 679 | top = SkIntToFixed(y); |
| 680 | SkFixed topLimit = top + SK_Fixed1; |
| 681 | SkFixed xSort = -SK_FixedMax; |
| 682 | for (active = first; active != activeLast; active = active->fNext) { |
| 683 | if (xSort > active->fX || topLimit > active->fLastY) { |
| 684 | yLast = y; // recompute bottom after all Ys are advanced |
| 685 | } |
| 686 | xSort = active->fX; |
| 687 | if (active->fWalkY < active->fLastY) { |
| 688 | active->advanceY(top); |
| 689 | } |
| 690 | } |
| 691 | for (active = first; active != activeLast; ) { |
| 692 | SkAntiEdge* next = active->fNext; |
| 693 | if (top >= active->fLastY) { |
| 694 | remove_edge(active); |
| 695 | } |
| 696 | active = next; |
| 697 | } |
| 698 | first = fHeadEdge.fNext; |
| 699 | } |
| 700 | SkAntiEdge* prev = activeLast->fPrev; |
| 701 | if (prev != &fHeadEdge) { |
| 702 | insert_new_edges(prev, top); |
| 703 | first = fHeadEdge.fNext; |
| 704 | } |
| 705 | } while (first->fWalkY < kEDGE_TAIL_XY); |
| 706 | } |
| 707 | |
| 708 | void SkAntiEdgeBuilder::process(const SkPoint* points, int ptCount, |
| 709 | uint8_t* result, int pixelCol, int pixelRow) { |
| 710 | if (ptCount < 3) { |
| 711 | return; |
| 712 | } |
| 713 | int count = build(points, ptCount); |
| 714 | if (count == 0) { |
| 715 | return; |
| 716 | } |
| 717 | SkAssertResult(count > 1); |
| 718 | link(); |
| 719 | sort(); |
| 720 | split(); |
| 721 | calc(); |
| 722 | walk(result, pixelCol, pixelRow); |
| 723 | } |
| 724 | |
| 725 | //////////////////////////////////////////////////////////////////////////////// |
| 726 | |
| 727 | int test3by3_test; |
| 728 | |
| 729 | // input is a rectangle |
| 730 | static void test_3_by_3() { |
| 731 | const int pixelRow = 3; |
| 732 | const int pixelCol = 3; |
| 733 | const int ptCount = 4; |
| 734 | const int pixelCount = pixelRow * pixelCol; |
| 735 | const SkPoint tests[][ptCount] = { |
| 736 | {{2.0f, 1.0f}, {1.0f, 1.0f}, {1.0f, 2.0f}, {2.0f, 2.0f}}, // 0: full rect |
| 737 | {{2.5f, 1.0f}, {1.5f, 1.0f}, {1.5f, 2.0f}, {2.5f, 2.0f}}, // 1: y edge |
| 738 | {{2.0f, 1.5f}, {1.0f, 1.5f}, {1.0f, 2.5f}, {2.0f, 2.5f}}, // 2: x edge |
| 739 | {{2.5f, 1.5f}, {1.5f, 1.5f}, {1.5f, 2.5f}, {2.5f, 2.5f}}, // 3: x/y edge |
| 740 | {{2.8f, 0.2f}, {0.2f, 0.2f}, {0.2f, 2.8f}, {2.8f, 2.8f}}, // 4: large |
| 741 | {{1.8f, 1.2f}, {1.2f, 1.2f}, {1.2f, 1.8f}, {1.8f, 1.8f}}, // 5: small |
| 742 | {{0.0f, 0.0f}, {0.0f, 1.0f}, {3.0f, 2.0f}, {3.0f, 1.0f}}, // 6: dy<dx |
| 743 | {{3.0f, 0.0f}, {0.0f, 1.0f}, {0.0f, 2.0f}, {3.0f, 1.0f}}, // 7: dy<-dx |
| 744 | {{1.0f, 0.0f}, {0.0f, 0.0f}, {1.0f, 3.0f}, {2.0f, 3.0f}}, // 8: dy>dx |
| 745 | {{2.0f, 0.0f}, {1.0f, 0.0f}, {0.0f, 3.0f}, {1.0f, 3.0f}}, // 9: dy>-dx |
| 746 | {{0.5f, 0.5f}, {0.5f, 1.5f}, {2.5f, 2.5f}, {2.5f, 1.5f}}, // 10: dy<dx 2 |
| 747 | {{2.5f, 0.5f}, {0.5f, 1.5f}, {0.5f, 2.5f}, {2.5f, 1.5f}}, // 11: dy<-dx 2 |
| 748 | {{0.0f, 0.0f}, {2.0f, 0.0f}, {2.0f, 2.0f}, {0.0f, 2.0f}}, // 12: 2x2 |
| 749 | {{0.0f, 0.0f}, {3.0f, 0.0f}, {3.0f, 3.0f}, {0.0f, 3.0f}}, // 13: 3x3 |
| 750 | {{1.75f, 0.25f}, {2.75f, 1.25f}, {1.25f, 2.75f}, {0.25f, 1.75f}}, // 14 |
| 751 | {{2.25f, 0.25f}, {2.75f, 0.75f}, {0.75f, 2.75f}, {0.25f, 2.25f}}, // 15 |
| 752 | {{0.25f, 0.75f}, {0.75f, 0.25f}, {2.75f, 2.25f}, {2.25f, 2.75f}}, // 16 |
| 753 | {{1.25f, 0.50f}, {1.75f, 0.25f}, {2.75f, 2.25f}, {2.25f, 2.50f}}, // 17 |
| 754 | {{1.00f, 0.75f}, {2.00f, 0.50f}, {2.00f, 1.50f}, {1.00f, 1.75f}}, // 18 |
| 755 | {{1.00f, 0.50f}, {2.00f, 0.75f}, {2.00f, 1.75f}, {1.00f, 1.50f}}, // 19 |
| 756 | {{1.00f, 0.75f}, {1.00f, 1.75f}, {2.00f, 1.50f}, {2.00f, 0.50f}}, // 20 |
| 757 | {{1.00f, 0.50f}, {1.00f, 1.50f}, {2.00f, 1.75f}, {2.00f, 0.75f}}, // 21 |
| 758 | }; |
| 759 | const uint8_t results[][pixelCount] = { |
| 760 | {0x00, 0x00, 0x00, // 0: 1 pixel rect |
| 761 | 0x00, 0xFF, 0x00, |
| 762 | 0x00, 0x00, 0x00}, |
| 763 | {0x00, 0x00, 0x00, // 1: y edge |
| 764 | 0x00, 0x7F, 0x80, |
| 765 | 0x00, 0x00, 0x00}, |
| 766 | {0x00, 0x00, 0x00, // 2: x edge |
| 767 | 0x00, 0x7F, 0x00, |
| 768 | 0x00, 0x7F, 0x00}, |
| 769 | {0x00, 0x00, 0x00, // 3: x/y edge |
| 770 | 0x00, 0x40, 0x40, |
| 771 | 0x00, 0x40, 0x40}, |
| 772 | {0xA3, 0xCC, 0xA3, // 4: large |
| 773 | 0xCC, 0xFF, 0xCC, |
| 774 | 0xA3, 0xCC, 0xA3}, |
| 775 | {0x00, 0x00, 0x00, // 5: small |
| 776 | 0x00, 0x5C, 0x00, |
| 777 | 0x00, 0x00, 0x00}, |
| 778 | {0xD5, 0x80, 0x2B, // 6: dy<dx |
| 779 | 0x2A, 0x7F, 0xD4, |
| 780 | 0x00, 0x00, 0x00}, |
| 781 | {0x2B, 0x80, 0xD5, // 7: dy<-dx |
| 782 | 0xD4, 0x7F, 0x2A, |
| 783 | 0x00, 0x00, 0x00}, |
| 784 | {0xD5, 0x2A, 0x00, // 8: dy>dx |
| 785 | 0x80, 0x7F, 0x00, |
| 786 | 0x2B, 0xD4, 0x00}, |
| 787 | {0x2A, 0xD5, 0x00, // 9: dy>-dx |
| 788 | 0x7F, 0x80, 0x00, |
| 789 | 0xD4, 0x2B, 0x00}, |
| 790 | {0x30, 0x10, 0x00, // 10: dy<dx 2 |
| 791 | 0x50, 0xDF, 0x50, |
| 792 | 0x00, 0x10, 0x30}, |
| 793 | {0x00, 0x10, 0x30, // 11: dy<-dx 2 |
| 794 | 0x50, 0xDF, 0x50, |
| 795 | 0x30, 0x10, 0x00}, |
| 796 | {0xFF, 0xFF, 0x00, // 12: 2x2 |
| 797 | 0xFF, 0xFF, 0x00, |
| 798 | 0x00, 0x00, 0x00}, |
| 799 | {0xFF, 0xFF, 0xFF, // 13: 3x3 |
| 800 | 0xFF, 0xFF, 0xFF, |
| 801 | 0xFF, 0xFF, 0xFF}, |
| 802 | {0x00, 0x70, 0x20, // 14 |
| 803 | 0x70, 0xFF, 0x70, |
| 804 | 0x20, 0x70, 0x00}, |
| 805 | {0x00, 0x20, 0x60, // 15 |
| 806 | 0x20, 0xBF, 0x20, |
| 807 | 0x60, 0x20, 0x00}, |
| 808 | {0x60, 0x20, 0x00, // 16 |
| 809 | 0x20, 0xBF, 0x20, |
| 810 | 0x00, 0x20, 0x60}, |
| 811 | {0x00, 0x60, 0x04, // 17 |
| 812 | 0x00, 0x40, 0x60, |
| 813 | 0x00, 0x00, 0x3C}, |
| 814 | {0x00, 0x60, 0x00, // 18 |
| 815 | 0x00, 0x9F, 0x00, |
| 816 | 0x00, 0x00, 0x00}, |
| 817 | {0x00, 0x60, 0x00, // 19 |
| 818 | 0x00, 0x9F, 0x00, |
| 819 | 0x00, 0x00, 0x00}, |
| 820 | {0x00, 0x60, 0x00, // 20 |
| 821 | 0x00, 0x9F, 0x00, |
| 822 | 0x00, 0x00, 0x00}, |
| 823 | {0x00, 0x60, 0x00, // 21 |
| 824 | 0x00, 0x9F, 0x00, |
| 825 | 0x00, 0x00, 0x00}, |
| 826 | }; |
| 827 | const int testCount = sizeof(tests) / sizeof(tests[0]); |
| 828 | SkAssertResult(testCount == sizeof(results) / sizeof(results[0])); |
| 829 | int testFirst = test3by3_test < 0 ? 0 : test3by3_test; |
| 830 | int testLast = test3by3_test < 0 ? testCount : test3by3_test + 1; |
| 831 | for (int testIndex = testFirst; testIndex < testLast; ++testIndex) { |
| 832 | uint8_t result[pixelRow][pixelCol]; |
| 833 | sk_bzero(result, sizeof(result)); |
| 834 | const SkPoint* rect = tests[testIndex]; |
| 835 | SkAntiEdgeBuilder builder; |
| 836 | builder.process(rect, ptCount, result[0], pixelCol, pixelRow); |
| 837 | SkAssertResult(memcmp(results[testIndex], result[0], pixelCount) == 0); |
| 838 | } |
| 839 | } |
| 840 | |
| 841 | // input has arbitrary number of points |
| 842 | static void test_arbitrary_3_by_3() { |
| 843 | const int pixelRow = 3; |
| 844 | const int pixelCol = 3; |
| 845 | const int pixelCount = pixelRow * pixelCol; |
| 846 | const SkPoint t1[] = { {1,1}, {2,1}, {2,1.5f}, {1,1.5f}, {1,2}, {2,2}, |
| 847 | {2,1.5f}, {1,1.5f}, {1,1} }; |
| 848 | const SkPoint* tests[] = { t1 }; |
| 849 | size_t testPts[] = { sizeof(t1) / sizeof(t1[0]) }; |
| 850 | const uint8_t results[][pixelCount] = { |
| 851 | {0x00, 0x00, 0x00, // 0: 1 pixel rect |
| 852 | 0x00, 0xFF, 0x00, |
| 853 | 0x00, 0x00, 0x00}, |
| 854 | }; |
| 855 | const int testCount = sizeof(tests) / sizeof(tests[0]); |
| 856 | SkAssertResult(testCount == sizeof(results) / sizeof(results[0])); |
| 857 | int testFirst = test3by3_test < 0 ? 0 : test3by3_test; |
| 858 | int testLast = test3by3_test < 0 ? testCount : test3by3_test + 1; |
| 859 | for (int testIndex = testFirst; testIndex < testLast; ++testIndex) { |
| 860 | uint8_t result[pixelRow][pixelCol]; |
| 861 | sk_bzero(result, sizeof(result)); |
| 862 | const SkPoint* pts = tests[testIndex]; |
| 863 | size_t ptCount = testPts[testIndex]; |
| 864 | SkAntiEdgeBuilder builder; |
| 865 | builder.process(pts, ptCount, result[0], pixelCol, pixelRow); |
| 866 | SkAssertResult(memcmp(results[testIndex], result[0], pixelCount) == 0); |
| 867 | } |
| 868 | } |
| 869 | |
| 870 | #include "SkRect.h" |
| 871 | #include "SkPath.h" |
| 872 | |
| 873 | int testsweep_test; |
| 874 | |
| 875 | static void create_sweep(uint8_t* result, int pixelRow, int pixelCol, SkScalar rectWidth) { |
| 876 | const int ptCount = 4; |
| 877 | SkRect refRect = {pixelCol / 2 - rectWidth / 2, 5, |
| 878 | pixelCol / 2 + rectWidth / 2, pixelRow / 2 - 5}; |
| 879 | SkPath refPath; |
| 880 | refPath.addRect(refRect); |
| 881 | SkScalar angleFirst = testsweep_test < 0 ? 0 : testsweep_test; |
| 882 | SkScalar angleLast = testsweep_test < 0 ? 360 : testsweep_test + 1; |
| 883 | for (SkScalar angle = angleFirst; angle < angleLast; angle += 12) { |
| 884 | SkPath rotPath; |
| 885 | SkMatrix matrix; |
| 886 | matrix.setRotate(angle, SkIntToScalar(pixelCol) / 2, |
| 887 | SkIntToScalar(pixelRow) / 2); |
| 888 | refPath.transform(matrix, &rotPath); |
| 889 | SkPoint rect[ptCount], temp[2]; |
| 890 | SkPath::Iter iter(rotPath, false); |
| 891 | int index = 0; |
| 892 | for (;;) { |
| 893 | SkPath::Verb verb = iter.next(temp); |
| 894 | if (verb == SkPath::kMove_Verb) { |
| 895 | continue; |
| 896 | } |
| 897 | if (verb == SkPath::kClose_Verb) { |
| 898 | break; |
| 899 | } |
| 900 | SkAssertResult(SkPath::kLine_Verb == verb); |
| 901 | rect[index++] = temp[0]; |
| 902 | } |
| 903 | SkAntiEdgeBuilder builder; |
| 904 | builder.process(rect, ptCount, result, pixelCol, pixelRow); |
| 905 | } |
| 906 | } |
| 907 | |
| 908 | static void create_horz(uint8_t* result, int pixelRow, int pixelCol) { |
| 909 | const int ptCount = 4; |
| 910 | for (SkScalar x = 0; x < 100; x += 5) { |
| 911 | SkPoint rect[ptCount]; |
| 912 | rect[0].fX = 0; rect[0].fY = x; |
| 913 | rect[1].fX = 100; rect[1].fY = x; |
| 914 | rect[2].fX = 100; rect[2].fY = x + x / 50; |
| 915 | rect[3].fX = 0; rect[3].fY = x + x / 50; |
| 916 | SkAntiEdgeBuilder builder; |
| 917 | builder.process(rect, ptCount, result, pixelCol, pixelRow); |
| 918 | } |
| 919 | } |
| 920 | |
| 921 | static void create_vert(uint8_t* result, int pixelRow, int pixelCol) { |
| 922 | const int ptCount = 4; |
| 923 | for (SkScalar x = 0; x < 100; x += 5) { |
| 924 | SkPoint rect[ptCount]; |
| 925 | rect[0].fY = 0; rect[0].fX = x; |
| 926 | rect[1].fY = 100; rect[1].fX = x; |
| 927 | rect[2].fY = 100; rect[2].fX = x + x / 50; |
| 928 | rect[3].fY = 0; rect[3].fX = x + x / 50; |
| 929 | SkAntiEdgeBuilder builder; |
| 930 | builder.process(rect, ptCount, result, pixelCol, pixelRow); |
| 931 | } |
| 932 | } |
| 933 | |
| 934 | static void create_angle(uint8_t* result, int pixelRow, int pixelCol, SkScalar angle) { |
| 935 | const int ptCount = 4; |
| 936 | SkRect refRect = {25, 25, 125, 125}; |
| 937 | SkPath refPath; |
| 938 | for (SkScalar x = 30; x < 125; x += 5) { |
| 939 | refRect.fTop = x; |
| 940 | refRect.fBottom = x + (x - 25) / 50; |
| 941 | refPath.addRect(refRect); |
| 942 | } |
| 943 | SkPath rotPath; |
| 944 | SkMatrix matrix; |
| 945 | matrix.setRotate(angle, 75, 75); |
| 946 | refPath.transform(matrix, &rotPath); |
| 947 | SkPath::Iter iter(rotPath, false); |
| 948 | for (SkScalar x = 30; x < 125; x += 5) { |
| 949 | SkPoint rect[ptCount], temp[2]; |
| 950 | int index = 0; |
| 951 | for (;;) { |
| 952 | SkPath::Verb verb = iter.next(temp); |
| 953 | if (verb == SkPath::kMove_Verb) { |
| 954 | continue; |
| 955 | } |
| 956 | if (verb == SkPath::kClose_Verb) { |
| 957 | break; |
| 958 | } |
| 959 | SkAssertResult(SkPath::kLine_Verb == verb); |
| 960 | rect[index++] = temp[0]; |
| 961 | } |
| 962 | // if ((x == 30 || x == 75) && angle == 12) continue; |
| 963 | SkAntiEdgeBuilder builder; |
| 964 | builder.process(rect, ptCount, result, pixelCol, pixelRow); |
| 965 | } |
| 966 | } |
| 967 | |
| 968 | static void test_sweep() { |
| 969 | const int pixelRow = 100; |
| 970 | const int pixelCol = 100; |
| 971 | uint8_t result[pixelRow][pixelCol]; |
| 972 | sk_bzero(result, sizeof(result)); |
| 973 | create_sweep(result[0], pixelRow, pixelCol, 1); |
| 974 | } |
| 975 | |
| 976 | static void test_horz() { |
| 977 | const int pixelRow = 100; |
| 978 | const int pixelCol = 100; |
| 979 | uint8_t result[pixelRow][pixelCol]; |
| 980 | sk_bzero(result, sizeof(result)); |
| 981 | create_horz(result[0], pixelRow, pixelCol); |
| 982 | } |
| 983 | |
| 984 | static void test_vert() { |
| 985 | const int pixelRow = 100; |
| 986 | const int pixelCol = 100; |
| 987 | uint8_t result[pixelRow][pixelCol]; |
| 988 | sk_bzero(result, sizeof(result)); |
| 989 | create_vert(result[0], pixelRow, pixelCol); |
| 990 | } |
| 991 | |
| 992 | static void test_angle(SkScalar angle) { |
| 993 | const int pixelRow = 150; |
| 994 | const int pixelCol = 150; |
| 995 | uint8_t result[pixelRow][pixelCol]; |
| 996 | sk_bzero(result, sizeof(result)); |
| 997 | create_angle(result[0], pixelRow, pixelCol, angle); |
| 998 | } |
| 999 | |
| 1000 | #include "SkBitmap.h" |
| 1001 | |
| 1002 | void CreateSweep(SkBitmap* sweep, SkScalar rectWidth) { |
| 1003 | const int pixelRow = 100; |
| 1004 | const int pixelCol = 100; |
| 1005 | sweep->setConfig(SkBitmap::kA8_Config, pixelCol, pixelRow); |
| 1006 | sweep->allocPixels(); |
junov@google.com | dbfac8a | 2012-12-06 21:47:40 +0000 | [diff] [blame] | 1007 | sweep->eraseColor(SK_ColorTRANSPARENT); |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1008 | sweep->lockPixels(); |
| 1009 | void* pixels = sweep->getPixels(); |
| 1010 | create_sweep((uint8_t*) pixels, pixelRow, pixelCol, rectWidth); |
| 1011 | sweep->unlockPixels(); |
| 1012 | } |
| 1013 | |
| 1014 | void CreateHorz(SkBitmap* sweep) { |
| 1015 | const int pixelRow = 100; |
| 1016 | const int pixelCol = 100; |
| 1017 | sweep->setConfig(SkBitmap::kA8_Config, pixelCol, pixelRow); |
| 1018 | sweep->allocPixels(); |
junov@google.com | dbfac8a | 2012-12-06 21:47:40 +0000 | [diff] [blame] | 1019 | sweep->eraseColor(SK_ColorTRANSPARENT); |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1020 | sweep->lockPixels(); |
| 1021 | void* pixels = sweep->getPixels(); |
| 1022 | create_horz((uint8_t*) pixels, pixelRow, pixelCol); |
| 1023 | sweep->unlockPixels(); |
| 1024 | } |
| 1025 | |
| 1026 | void CreateVert(SkBitmap* sweep) { |
| 1027 | const int pixelRow = 100; |
| 1028 | const int pixelCol = 100; |
| 1029 | sweep->setConfig(SkBitmap::kA8_Config, pixelCol, pixelRow); |
| 1030 | sweep->allocPixels(); |
junov@google.com | dbfac8a | 2012-12-06 21:47:40 +0000 | [diff] [blame] | 1031 | sweep->eraseColor(SK_ColorTRANSPARENT); |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1032 | sweep->lockPixels(); |
| 1033 | void* pixels = sweep->getPixels(); |
| 1034 | create_vert((uint8_t*) pixels, pixelRow, pixelCol); |
| 1035 | sweep->unlockPixels(); |
| 1036 | } |
| 1037 | |
| 1038 | void CreateAngle(SkBitmap* sweep, SkScalar angle) { |
| 1039 | const int pixelRow = 150; |
| 1040 | const int pixelCol = 150; |
| 1041 | sweep->setConfig(SkBitmap::kA8_Config, pixelCol, pixelRow); |
| 1042 | sweep->allocPixels(); |
junov@google.com | dbfac8a | 2012-12-06 21:47:40 +0000 | [diff] [blame] | 1043 | sweep->eraseColor(SK_ColorTRANSPARENT); |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1044 | sweep->lockPixels(); |
| 1045 | void* pixels = sweep->getPixels(); |
| 1046 | create_angle((uint8_t*) pixels, pixelRow, pixelCol, angle); |
| 1047 | sweep->unlockPixels(); |
| 1048 | } |
| 1049 | |
| 1050 | #include "SkCanvas.h" |
| 1051 | |
| 1052 | static void testPng() { |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1053 | SkBitmap device; |
| 1054 | device.setConfig(SkBitmap::kARGB_8888_Config, 4, 4); |
| 1055 | device.allocPixels(); |
| 1056 | device.eraseColor(0xFFFFFFFF); |
reed@google.com | 82ba677 | 2012-09-28 19:09:23 +0000 | [diff] [blame] | 1057 | |
| 1058 | SkCanvas canvas(device); |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1059 | canvas.drawARGB(167, 0, 0, 0); |
reed@google.com | 82ba677 | 2012-09-28 19:09:23 +0000 | [diff] [blame] | 1060 | |
caryclark@google.com | 639df89 | 2012-01-10 21:46:10 +0000 | [diff] [blame] | 1061 | device.lockPixels(); |
| 1062 | unsigned char* pixels = (unsigned char*) device.getPixels(); |
| 1063 | SkDebugf("%02x%02x%02x%02x", pixels[3], pixels[2], pixels[1], pixels[0]); |
| 1064 | } |
| 1065 | |
| 1066 | void SkAntiEdge_Test() { |
| 1067 | testPng(); |
| 1068 | test_arbitrary_3_by_3(); |
| 1069 | test_angle(12); |
| 1070 | #if 0 |
| 1071 | test3by3_test = 18; |
| 1072 | #else |
| 1073 | test3by3_test = -1; |
| 1074 | #endif |
| 1075 | #if 0 |
| 1076 | testsweep_test = 7 * 12; |
| 1077 | #else |
| 1078 | testsweep_test = -1; |
| 1079 | #endif |
| 1080 | if (testsweep_test == -1) { |
| 1081 | test_3_by_3(); |
| 1082 | } |
| 1083 | test_sweep(); |
| 1084 | test_horz(); |
| 1085 | test_vert(); |
| 1086 | } |