| 1 | /* |
| 2 | * Copyright 2006 The Android Open Source Project |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
| 7 | |
| 8 | #include "include/core/SkPaint.h" |
| 9 | #include "src/core/SkBlitter.h" |
| 10 | #include "src/core/SkFDot6.h" |
| 11 | #include "src/core/SkLineClipper.h" |
| 12 | #include "src/core/SkMathPriv.h" |
| 13 | #include "src/core/SkRasterClip.h" |
| 14 | #include "src/core/SkScan.h" |
| 15 | |
| 16 | #include <utility> |
| 17 | |
| 18 | static void horiline(int x, int stopx, SkFixed fy, SkFixed dy, |
| 19 | SkBlitter* blitter) { |
| 20 | SkASSERT(x < stopx); |
| 21 | |
| 22 | do { |
| 23 | blitter->blitH(x, fy >> 16, 1); |
| 24 | fy += dy; |
| 25 | } while (++x < stopx); |
| 26 | } |
| 27 | |
| 28 | static void vertline(int y, int stopy, SkFixed fx, SkFixed dx, |
| 29 | SkBlitter* blitter) { |
| 30 | SkASSERT(y < stopy); |
| 31 | |
| 32 | do { |
| 33 | blitter->blitH(fx >> 16, y, 1); |
| 34 | fx += dx; |
| 35 | } while (++y < stopy); |
| 36 | } |
| 37 | |
| 38 | #ifdef SK_DEBUG |
| 39 | static bool canConvertFDot6ToFixed(SkFDot6 x) { |
| 40 | const int maxDot6 = SK_MaxS32 >> (16 - 6); |
| 41 | return SkAbs32(x) <= maxDot6; |
| 42 | } |
| 43 | #endif |
| 44 | |
| 45 | void SkScan::HairLineRgn(const SkPoint array[], int arrayCount, const SkRegion* clip, |
| 46 | SkBlitter* origBlitter) { |
| 47 | SkBlitterClipper clipper; |
| 48 | SkIRect clipR, ptsR; |
| 49 | |
| 50 | const SkScalar max = SkIntToScalar(32767); |
| 51 | const SkRect fixedBounds = SkRect::MakeLTRB(-max, -max, max, max); |
| 52 | |
| 53 | SkRect clipBounds; |
| 54 | if (clip) { |
| 55 | clipBounds.set(clip->getBounds()); |
| 56 | } |
| 57 | |
| 58 | for (int i = 0; i < arrayCount - 1; ++i) { |
| 59 | SkBlitter* blitter = origBlitter; |
| 60 | |
| 61 | SkPoint pts[2]; |
| 62 | |
| 63 | // We have to pre-clip the line to fit in a SkFixed, so we just chop |
| 64 | // the line. TODO find a way to actually draw beyond that range. |
| 65 | if (!SkLineClipper::IntersectLine(&array[i], fixedBounds, pts)) { |
| 66 | continue; |
| 67 | } |
| 68 | |
| 69 | // Perform a clip in scalar space, so we catch huge values which might |
| 70 | // be missed after we convert to SkFDot6 (overflow) |
| 71 | if (clip && !SkLineClipper::IntersectLine(pts, clipBounds, pts)) { |
| 72 | continue; |
| 73 | } |
| 74 | |
| 75 | SkFDot6 x0 = SkScalarToFDot6(pts[0].fX); |
| 76 | SkFDot6 y0 = SkScalarToFDot6(pts[0].fY); |
| 77 | SkFDot6 x1 = SkScalarToFDot6(pts[1].fX); |
| 78 | SkFDot6 y1 = SkScalarToFDot6(pts[1].fY); |
| 79 | |
| 80 | SkASSERT(canConvertFDot6ToFixed(x0)); |
| 81 | SkASSERT(canConvertFDot6ToFixed(y0)); |
| 82 | SkASSERT(canConvertFDot6ToFixed(x1)); |
| 83 | SkASSERT(canConvertFDot6ToFixed(y1)); |
| 84 | |
| 85 | if (clip) { |
| 86 | // now perform clipping again, as the rounding to dot6 can wiggle us |
| 87 | // our rects are really dot6 rects, but since we've already used |
| 88 | // lineclipper, we know they will fit in 32bits (26.6) |
| 89 | const SkIRect& bounds = clip->getBounds(); |
| 90 | |
| 91 | clipR.setLTRB(SkIntToFDot6(bounds.fLeft), SkIntToFDot6(bounds.fTop), |
| 92 | SkIntToFDot6(bounds.fRight), SkIntToFDot6(bounds.fBottom)); |
| 93 | ptsR.setLTRB(x0, y0, x1, y1); |
| 94 | ptsR.sort(); |
| 95 | |
| 96 | // outset the right and bottom, to account for how hairlines are |
| 97 | // actually drawn, which may hit the pixel to the right or below of |
| 98 | // the coordinate |
| 99 | ptsR.fRight += SK_FDot6One; |
| 100 | ptsR.fBottom += SK_FDot6One; |
| 101 | |
| 102 | if (!SkIRect::Intersects(ptsR, clipR)) { |
| 103 | continue; |
| 104 | } |
| 105 | if (!clip->isRect() || !clipR.contains(ptsR)) { |
| 106 | blitter = clipper.apply(origBlitter, clip); |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | SkFDot6 dx = x1 - x0; |
| 111 | SkFDot6 dy = y1 - y0; |
| 112 | |
| 113 | if (SkAbs32(dx) > SkAbs32(dy)) { // mostly horizontal |
| 114 | if (x0 > x1) { // we want to go left-to-right |
| 115 | using std::swap; |
| 116 | swap(x0, x1); |
| 117 | swap(y0, y1); |
| 118 | } |
| 119 | int ix0 = SkFDot6Round(x0); |
| 120 | int ix1 = SkFDot6Round(x1); |
| 121 | if (ix0 == ix1) {// too short to draw |
| 122 | continue; |
| 123 | } |
| 124 | |
| 125 | SkFixed slope = SkFixedDiv(dy, dx); |
| 126 | SkFixed startY = SkFDot6ToFixed(y0) + (slope * ((32 - x0) & 63) >> 6); |
| 127 | |
| 128 | horiline(ix0, ix1, startY, slope, blitter); |
| 129 | } else { // mostly vertical |
| 130 | if (y0 > y1) { // we want to go top-to-bottom |
| 131 | using std::swap; |
| 132 | swap(x0, x1); |
| 133 | swap(y0, y1); |
| 134 | } |
| 135 | int iy0 = SkFDot6Round(y0); |
| 136 | int iy1 = SkFDot6Round(y1); |
| 137 | if (iy0 == iy1) { // too short to draw |
| 138 | continue; |
| 139 | } |
| 140 | |
| 141 | SkFixed slope = SkFixedDiv(dx, dy); |
| 142 | SkFixed startX = SkFDot6ToFixed(x0) + (slope * ((32 - y0) & 63) >> 6); |
| 143 | |
| 144 | vertline(iy0, iy1, startX, slope, blitter); |
| 145 | } |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | // we don't just draw 4 lines, 'cause that can leave a gap in the bottom-right |
| 150 | // and double-hit the top-left. |
| 151 | void SkScan::HairRect(const SkRect& rect, const SkRasterClip& clip, SkBlitter* blitter) { |
| 152 | SkAAClipBlitterWrapper wrapper; |
| 153 | SkBlitterClipper clipper; |
| 154 | // Create the enclosing bounds of the hairrect. i.e. we will stroke the interior of r. |
| 155 | SkIRect r = SkIRect::MakeLTRB(SkScalarFloorToInt(rect.fLeft), |
| 156 | SkScalarFloorToInt(rect.fTop), |
| 157 | SkScalarFloorToInt(rect.fRight + 1), |
| 158 | SkScalarFloorToInt(rect.fBottom + 1)); |
| 159 | |
| 160 | // Note: r might be crazy big, if rect was huge, possibly getting pinned to max/min s32. |
| 161 | // We need to trim it back to something reasonable before we can query its width etc. |
| 162 | // since r.fRight - r.fLeft might wrap around to negative even if fRight > fLeft. |
| 163 | // |
| 164 | // We outset the clip bounds by 1 before intersecting, since r is being stroked and not filled |
| 165 | // so we don't want to pin an edge of it to the clip. The intersect's job is mostly to just |
| 166 | // get the actual edge values into a reasonable range (e.g. so width() can't overflow). |
| 167 | if (!r.intersect(clip.getBounds().makeOutset(1, 1))) { |
| 168 | return; |
| 169 | } |
| 170 | |
| 171 | if (clip.quickReject(r)) { |
| 172 | return; |
| 173 | } |
| 174 | if (!clip.quickContains(r)) { |
| 175 | const SkRegion* clipRgn; |
| 176 | if (clip.isBW()) { |
| 177 | clipRgn = &clip.bwRgn(); |
| 178 | } else { |
| 179 | wrapper.init(clip, blitter); |
| 180 | clipRgn = &wrapper.getRgn(); |
| 181 | blitter = wrapper.getBlitter(); |
| 182 | } |
| 183 | blitter = clipper.apply(blitter, clipRgn); |
| 184 | } |
| 185 | |
| 186 | int width = r.width(); |
| 187 | int height = r.height(); |
| 188 | |
| 189 | if ((width | height) == 0) { |
| 190 | return; |
| 191 | } |
| 192 | if (width <= 2 || height <= 2) { |
| 193 | blitter->blitRect(r.fLeft, r.fTop, width, height); |
| 194 | return; |
| 195 | } |
| 196 | // if we get here, we know we have 4 segments to draw |
| 197 | blitter->blitH(r.fLeft, r.fTop, width); // top |
| 198 | blitter->blitRect(r.fLeft, r.fTop + 1, 1, height - 2); // left |
| 199 | blitter->blitRect(r.fRight - 1, r.fTop + 1, 1, height - 2); // right |
| 200 | blitter->blitH(r.fLeft, r.fBottom - 1, width); // bottom |
| 201 | } |
| 202 | |
| 203 | /////////////////////////////////////////////////////////////////////////////// |
| 204 | |
| 205 | #include "include/core/SkPath.h" |
| 206 | #include "include/private/SkNx.h" |
| 207 | #include "src/core/SkGeometry.h" |
| 208 | |
| 209 | #define kMaxCubicSubdivideLevel 9 |
| 210 | #define kMaxQuadSubdivideLevel 5 |
| 211 | |
| 212 | static uint32_t compute_int_quad_dist(const SkPoint pts[3]) { |
| 213 | // compute the vector between the control point ([1]) and the middle of the |
| 214 | // line connecting the start and end ([0] and [2]) |
| 215 | SkScalar dx = SkScalarHalf(pts[0].fX + pts[2].fX) - pts[1].fX; |
| 216 | SkScalar dy = SkScalarHalf(pts[0].fY + pts[2].fY) - pts[1].fY; |
| 217 | // we want everyone to be positive |
| 218 | dx = SkScalarAbs(dx); |
| 219 | dy = SkScalarAbs(dy); |
| 220 | // convert to whole pixel values (use ceiling to be conservative). |
| 221 | // assign to unsigned so we can safely add 1/2 of the smaller and still fit in |
| 222 | // uint32_t, since SkScalarCeilToInt() returns 31 bits at most. |
| 223 | uint32_t idx = SkScalarCeilToInt(dx); |
| 224 | uint32_t idy = SkScalarCeilToInt(dy); |
| 225 | // use the cheap approx for distance |
| 226 | if (idx > idy) { |
| 227 | return idx + (idy >> 1); |
| 228 | } else { |
| 229 | return idy + (idx >> 1); |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | static void hair_quad(const SkPoint pts[3], const SkRegion* clip, |
| 234 | SkBlitter* blitter, int level, SkScan::HairRgnProc lineproc) { |
| 235 | SkASSERT(level <= kMaxQuadSubdivideLevel); |
| 236 | |
| 237 | SkQuadCoeff coeff(pts); |
| 238 | |
| 239 | const int lines = 1 << level; |
| 240 | Sk2s t(0); |
| 241 | Sk2s dt(SK_Scalar1 / lines); |
| 242 | |
| 243 | SkPoint tmp[(1 << kMaxQuadSubdivideLevel) + 1]; |
| 244 | SkASSERT((unsigned)lines < SK_ARRAY_COUNT(tmp)); |
| 245 | |
| 246 | tmp[0] = pts[0]; |
| 247 | Sk2s A = coeff.fA; |
| 248 | Sk2s B = coeff.fB; |
| 249 | Sk2s C = coeff.fC; |
| 250 | for (int i = 1; i < lines; ++i) { |
| 251 | t = t + dt; |
| 252 | ((A * t + B) * t + C).store(&tmp[i]); |
| 253 | } |
| 254 | tmp[lines] = pts[2]; |
| 255 | lineproc(tmp, lines + 1, clip, blitter); |
| 256 | } |
| 257 | |
| 258 | static SkRect compute_nocheck_quad_bounds(const SkPoint pts[3]) { |
| 259 | SkASSERT(SkScalarsAreFinite(&pts[0].fX, 6)); |
| 260 | |
| 261 | Sk2s min = Sk2s::Load(pts); |
| 262 | Sk2s max = min; |
| 263 | for (int i = 1; i < 3; ++i) { |
| 264 | Sk2s pair = Sk2s::Load(pts+i); |
| 265 | min = Sk2s::Min(min, pair); |
| 266 | max = Sk2s::Max(max, pair); |
| 267 | } |
| 268 | return { min[0], min[1], max[0], max[1] }; |
| 269 | } |
| 270 | |
| 271 | static bool is_inverted(const SkRect& r) { |
| 272 | return r.fLeft > r.fRight || r.fTop > r.fBottom; |
| 273 | } |
| 274 | |
| 275 | // Can't call SkRect::intersects, since it cares about empty, and we don't (since we tracking |
| 276 | // something to be stroked, so empty can still draw something (e.g. horizontal line) |
| 277 | static bool geometric_overlap(const SkRect& a, const SkRect& b) { |
| 278 | SkASSERT(!is_inverted(a) && !is_inverted(b)); |
| 279 | return a.fLeft < b.fRight && b.fLeft < a.fRight && |
| 280 | a.fTop < b.fBottom && b.fTop < a.fBottom; |
| 281 | } |
| 282 | |
| 283 | // Can't call SkRect::contains, since it cares about empty, and we don't (since we tracking |
| 284 | // something to be stroked, so empty can still draw something (e.g. horizontal line) |
| 285 | static bool geometric_contains(const SkRect& outer, const SkRect& inner) { |
| 286 | SkASSERT(!is_inverted(outer) && !is_inverted(inner)); |
| 287 | return inner.fRight <= outer.fRight && inner.fLeft >= outer.fLeft && |
| 288 | inner.fBottom <= outer.fBottom && inner.fTop >= outer.fTop; |
| 289 | } |
| 290 | |
| 291 | static inline void hairquad(const SkPoint pts[3], const SkRegion* clip, const SkRect* insetClip, const SkRect* outsetClip, |
| 292 | SkBlitter* blitter, int level, SkScan::HairRgnProc lineproc) { |
| 293 | if (insetClip) { |
| 294 | SkASSERT(outsetClip); |
| 295 | SkRect bounds = compute_nocheck_quad_bounds(pts); |
| 296 | if (!geometric_overlap(*outsetClip, bounds)) { |
| 297 | return; |
| 298 | } else if (geometric_contains(*insetClip, bounds)) { |
| 299 | clip = nullptr; |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | hair_quad(pts, clip, blitter, level, lineproc); |
| 304 | } |
| 305 | |
| 306 | static inline Sk2s abs(const Sk2s& value) { |
| 307 | return Sk2s::Max(value, Sk2s(0)-value); |
| 308 | } |
| 309 | |
| 310 | static inline SkScalar max_component(const Sk2s& value) { |
| 311 | SkScalar components[2]; |
| 312 | value.store(components); |
| 313 | return std::max(components[0], components[1]); |
| 314 | } |
| 315 | |
| 316 | static inline int compute_cubic_segs(const SkPoint pts[4]) { |
| 317 | Sk2s p0 = from_point(pts[0]); |
| 318 | Sk2s p1 = from_point(pts[1]); |
| 319 | Sk2s p2 = from_point(pts[2]); |
| 320 | Sk2s p3 = from_point(pts[3]); |
| 321 | |
| 322 | const Sk2s oneThird(1.0f / 3.0f); |
| 323 | const Sk2s twoThird(2.0f / 3.0f); |
| 324 | |
| 325 | Sk2s p13 = oneThird * p3 + twoThird * p0; |
| 326 | Sk2s p23 = oneThird * p0 + twoThird * p3; |
| 327 | |
| 328 | SkScalar diff = max_component(Sk2s::Max(abs(p1 - p13), abs(p2 - p23))); |
| 329 | SkScalar tol = SK_Scalar1 / 8; |
| 330 | |
| 331 | for (int i = 0; i < kMaxCubicSubdivideLevel; ++i) { |
| 332 | if (diff < tol) { |
| 333 | return 1 << i; |
| 334 | } |
| 335 | tol *= 4; |
| 336 | } |
| 337 | return 1 << kMaxCubicSubdivideLevel; |
| 338 | } |
| 339 | |
| 340 | static bool lt_90(SkPoint p0, SkPoint pivot, SkPoint p2) { |
| 341 | return SkVector::DotProduct(p0 - pivot, p2 - pivot) >= 0; |
| 342 | } |
| 343 | |
| 344 | // The off-curve points are "inside" the limits of the on-curve pts |
| 345 | static bool quick_cubic_niceness_check(const SkPoint pts[4]) { |
| 346 | return lt_90(pts[1], pts[0], pts[3]) && |
| 347 | lt_90(pts[2], pts[0], pts[3]) && |
| 348 | lt_90(pts[1], pts[3], pts[0]) && |
| 349 | lt_90(pts[2], pts[3], pts[0]); |
| 350 | } |
| 351 | |
| 352 | typedef SkNx<2, uint32_t> Sk2x32; |
| 353 | |
| 354 | static inline Sk2x32 sk2s_is_finite(const Sk2s& x) { |
| 355 | const Sk2x32 exp_mask = Sk2x32(0xFF << 23); |
| 356 | return (Sk2x32::Load(&x) & exp_mask) != exp_mask; |
| 357 | } |
| 358 | |
| 359 | static void hair_cubic(const SkPoint pts[4], const SkRegion* clip, SkBlitter* blitter, |
| 360 | SkScan::HairRgnProc lineproc) { |
| 361 | const int lines = compute_cubic_segs(pts); |
| 362 | SkASSERT(lines > 0); |
| 363 | if (1 == lines) { |
| 364 | SkPoint tmp[2] = { pts[0], pts[3] }; |
| 365 | lineproc(tmp, 2, clip, blitter); |
| 366 | return; |
| 367 | } |
| 368 | |
| 369 | SkCubicCoeff coeff(pts); |
| 370 | |
| 371 | const Sk2s dt(SK_Scalar1 / lines); |
| 372 | Sk2s t(0); |
| 373 | |
| 374 | SkPoint tmp[(1 << kMaxCubicSubdivideLevel) + 1]; |
| 375 | SkASSERT((unsigned)lines < SK_ARRAY_COUNT(tmp)); |
| 376 | |
| 377 | tmp[0] = pts[0]; |
| 378 | Sk2s A = coeff.fA; |
| 379 | Sk2s B = coeff.fB; |
| 380 | Sk2s C = coeff.fC; |
| 381 | Sk2s D = coeff.fD; |
| 382 | Sk2x32 is_finite(~0); // start out as true |
| 383 | for (int i = 1; i < lines; ++i) { |
| 384 | t = t + dt; |
| 385 | Sk2s p = ((A * t + B) * t + C) * t + D; |
| 386 | is_finite &= sk2s_is_finite(p); |
| 387 | p.store(&tmp[i]); |
| 388 | } |
| 389 | if (is_finite.allTrue()) { |
| 390 | tmp[lines] = pts[3]; |
| 391 | lineproc(tmp, lines + 1, clip, blitter); |
| 392 | } // else some point(s) are non-finite, so don't draw |
| 393 | } |
| 394 | |
| 395 | static SkRect compute_nocheck_cubic_bounds(const SkPoint pts[4]) { |
| 396 | SkASSERT(SkScalarsAreFinite(&pts[0].fX, 8)); |
| 397 | |
| 398 | Sk2s min = Sk2s::Load(pts); |
| 399 | Sk2s max = min; |
| 400 | for (int i = 1; i < 4; ++i) { |
| 401 | Sk2s pair = Sk2s::Load(pts+i); |
| 402 | min = Sk2s::Min(min, pair); |
| 403 | max = Sk2s::Max(max, pair); |
| 404 | } |
| 405 | return { min[0], min[1], max[0], max[1] }; |
| 406 | } |
| 407 | |
| 408 | static inline void haircubic(const SkPoint pts[4], const SkRegion* clip, const SkRect* insetClip, const SkRect* outsetClip, |
| 409 | SkBlitter* blitter, int level, SkScan::HairRgnProc lineproc) { |
| 410 | if (insetClip) { |
| 411 | SkASSERT(outsetClip); |
| 412 | SkRect bounds = compute_nocheck_cubic_bounds(pts); |
| 413 | if (!geometric_overlap(*outsetClip, bounds)) { |
| 414 | return; |
| 415 | } else if (geometric_contains(*insetClip, bounds)) { |
| 416 | clip = nullptr; |
| 417 | } |
| 418 | } |
| 419 | |
| 420 | if (quick_cubic_niceness_check(pts)) { |
| 421 | hair_cubic(pts, clip, blitter, lineproc); |
| 422 | } else { |
| 423 | SkPoint tmp[13]; |
| 424 | SkScalar tValues[3]; |
| 425 | |
| 426 | int count = SkChopCubicAtMaxCurvature(pts, tmp, tValues); |
| 427 | for (int i = 0; i < count; i++) { |
| 428 | hair_cubic(&tmp[i * 3], clip, blitter, lineproc); |
| 429 | } |
| 430 | } |
| 431 | } |
| 432 | |
| 433 | static int compute_quad_level(const SkPoint pts[3]) { |
| 434 | uint32_t d = compute_int_quad_dist(pts); |
| 435 | /* quadratics approach the line connecting their start and end points |
| 436 | 4x closer with each subdivision, so we compute the number of |
| 437 | subdivisions to be the minimum need to get that distance to be less |
| 438 | than a pixel. |
| 439 | */ |
| 440 | int level = (33 - SkCLZ(d)) >> 1; |
| 441 | // sanity check on level (from the previous version) |
| 442 | if (level > kMaxQuadSubdivideLevel) { |
| 443 | level = kMaxQuadSubdivideLevel; |
| 444 | } |
| 445 | return level; |
| 446 | } |
| 447 | |
| 448 | /* Extend the points in the direction of the starting or ending tangent by 1/2 unit to |
| 449 | account for a round or square cap. If there's no distance between the end point and |
| 450 | the control point, use the next control point to create a tangent. If the curve |
| 451 | is degenerate, move the cap out 1/2 unit horizontally. */ |
| 452 | template <SkPaint::Cap capStyle> |
| 453 | void extend_pts(SkPath::Verb prevVerb, SkPath::Verb nextVerb, SkPoint* pts, int ptCount) { |
| 454 | SkASSERT(SkPaint::kSquare_Cap == capStyle || SkPaint::kRound_Cap == capStyle); |
| 455 | // The area of a circle is PI*R*R. For a unit circle, R=1/2, and the cap covers half of that. |
| 456 | const SkScalar capOutset = SkPaint::kSquare_Cap == capStyle ? 0.5f : SK_ScalarPI / 8; |
| 457 | if (SkPath::kMove_Verb == prevVerb) { |
| 458 | SkPoint* first = pts; |
| 459 | SkPoint* ctrl = first; |
| 460 | int controls = ptCount - 1; |
| 461 | SkVector tangent; |
| 462 | do { |
| 463 | tangent = *first - *++ctrl; |
| 464 | } while (tangent.isZero() && --controls > 0); |
| 465 | if (tangent.isZero()) { |
| 466 | tangent.set(1, 0); |
| 467 | controls = ptCount - 1; // If all points are equal, move all but one |
| 468 | } else { |
| 469 | tangent.normalize(); |
| 470 | } |
| 471 | do { // If the end point and control points are equal, loop to move them in tandem. |
| 472 | first->fX += tangent.fX * capOutset; |
| 473 | first->fY += tangent.fY * capOutset; |
| 474 | ++first; |
| 475 | } while (++controls < ptCount); |
| 476 | } |
| 477 | if (SkPath::kMove_Verb == nextVerb || SkPath::kDone_Verb == nextVerb |
| 478 | || SkPath::kClose_Verb == nextVerb) { |
| 479 | SkPoint* last = &pts[ptCount - 1]; |
| 480 | SkPoint* ctrl = last; |
| 481 | int controls = ptCount - 1; |
| 482 | SkVector tangent; |
| 483 | do { |
| 484 | tangent = *last - *--ctrl; |
| 485 | } while (tangent.isZero() && --controls > 0); |
| 486 | if (tangent.isZero()) { |
| 487 | tangent.set(-1, 0); |
| 488 | controls = ptCount - 1; |
| 489 | } else { |
| 490 | tangent.normalize(); |
| 491 | } |
| 492 | do { |
| 493 | last->fX += tangent.fX * capOutset; |
| 494 | last->fY += tangent.fY * capOutset; |
| 495 | --last; |
| 496 | } while (++controls < ptCount); |
| 497 | } |
| 498 | } |
| 499 | |
| 500 | template <SkPaint::Cap capStyle> |
| 501 | void hair_path(const SkPath& path, const SkRasterClip& rclip, SkBlitter* blitter, |
| 502 | SkScan::HairRgnProc lineproc) { |
| 503 | if (path.isEmpty()) { |
| 504 | return; |
| 505 | } |
| 506 | |
| 507 | SkAAClipBlitterWrapper wrap; |
| 508 | const SkRegion* clip = nullptr; |
| 509 | SkRect insetStorage, outsetStorage; |
| 510 | const SkRect* insetClip = nullptr; |
| 511 | const SkRect* outsetClip = nullptr; |
| 512 | |
| 513 | { |
| 514 | const int capOut = SkPaint::kButt_Cap == capStyle ? 1 : 2; |
| 515 | const SkIRect ibounds = path.getBounds().roundOut().makeOutset(capOut, capOut); |
| 516 | if (rclip.quickReject(ibounds)) { |
| 517 | return; |
| 518 | } |
| 519 | if (!rclip.quickContains(ibounds)) { |
| 520 | if (rclip.isBW()) { |
| 521 | clip = &rclip.bwRgn(); |
| 522 | } else { |
| 523 | wrap.init(rclip, blitter); |
| 524 | blitter = wrap.getBlitter(); |
| 525 | clip = &wrap.getRgn(); |
| 526 | } |
| 527 | |
| 528 | /* |
| 529 | * We now cache two scalar rects, to use for culling per-segment (e.g. cubic). |
| 530 | * Since we're hairlining, the "bounds" of the control points isn't necessairly the |
| 531 | * limit of where a segment can draw (it might draw up to 1 pixel beyond in aa-hairs). |
| 532 | * |
| 533 | * Compute the pt-bounds per segment is easy, so we do that, and then inversely adjust |
| 534 | * the culling bounds so we can just do a straight compare per segment. |
| 535 | * |
| 536 | * insetClip is use for quick-accept (i.e. the segment is not clipped), so we inset |
| 537 | * it from the clip-bounds (since segment bounds can be off by 1). |
| 538 | * |
| 539 | * outsetClip is used for quick-reject (i.e. the segment is entirely outside), so we |
| 540 | * outset it from the clip-bounds. |
| 541 | */ |
| 542 | insetStorage.set(clip->getBounds()); |
| 543 | outsetStorage = insetStorage.makeOutset(1, 1); |
| 544 | insetStorage.inset(1, 1); |
| 545 | if (is_inverted(insetStorage)) { |
| 546 | /* |
| 547 | * our bounds checks assume the rects are never inverted. If insetting has |
| 548 | * created that, we assume that the area is too small to safely perform a |
| 549 | * quick-accept, so we just mark the rect as empty (so the quick-accept check |
| 550 | * will always fail. |
| 551 | */ |
| 552 | insetStorage.setEmpty(); // just so we don't pass an inverted rect |
| 553 | } |
| 554 | if (rclip.isRect()) { |
| 555 | insetClip = &insetStorage; |
| 556 | } |
| 557 | outsetClip = &outsetStorage; |
| 558 | } |
| 559 | } |
| 560 | |
| 561 | SkPath::RawIter iter(path); |
| 562 | SkPoint pts[4], firstPt, lastPt; |
| 563 | SkPath::Verb verb, prevVerb; |
| 564 | SkAutoConicToQuads converter; |
| 565 | |
| 566 | if (SkPaint::kButt_Cap != capStyle) { |
| 567 | prevVerb = SkPath::kDone_Verb; |
| 568 | } |
| 569 | while ((verb = iter.next(pts)) != SkPath::kDone_Verb) { |
| 570 | switch (verb) { |
| 571 | case SkPath::kMove_Verb: |
| 572 | firstPt = lastPt = pts[0]; |
| 573 | break; |
| 574 | case SkPath::kLine_Verb: |
| 575 | if (SkPaint::kButt_Cap != capStyle) { |
| 576 | extend_pts<capStyle>(prevVerb, iter.peek(), pts, 2); |
| 577 | } |
| 578 | lineproc(pts, 2, clip, blitter); |
| 579 | lastPt = pts[1]; |
| 580 | break; |
| 581 | case SkPath::kQuad_Verb: |
| 582 | if (SkPaint::kButt_Cap != capStyle) { |
| 583 | extend_pts<capStyle>(prevVerb, iter.peek(), pts, 3); |
| 584 | } |
| 585 | hairquad(pts, clip, insetClip, outsetClip, blitter, compute_quad_level(pts), lineproc); |
| 586 | lastPt = pts[2]; |
| 587 | break; |
| 588 | case SkPath::kConic_Verb: { |
| 589 | if (SkPaint::kButt_Cap != capStyle) { |
| 590 | extend_pts<capStyle>(prevVerb, iter.peek(), pts, 3); |
| 591 | } |
| 592 | // how close should the quads be to the original conic? |
| 593 | const SkScalar tol = SK_Scalar1 / 4; |
| 594 | const SkPoint* quadPts = converter.computeQuads(pts, |
| 595 | iter.conicWeight(), tol); |
| 596 | for (int i = 0; i < converter.countQuads(); ++i) { |
| 597 | int level = compute_quad_level(quadPts); |
| 598 | hairquad(quadPts, clip, insetClip, outsetClip, blitter, level, lineproc); |
| 599 | quadPts += 2; |
| 600 | } |
| 601 | lastPt = pts[2]; |
| 602 | break; |
| 603 | } |
| 604 | case SkPath::kCubic_Verb: { |
| 605 | if (SkPaint::kButt_Cap != capStyle) { |
| 606 | extend_pts<capStyle>(prevVerb, iter.peek(), pts, 4); |
| 607 | } |
| 608 | haircubic(pts, clip, insetClip, outsetClip, blitter, kMaxCubicSubdivideLevel, lineproc); |
| 609 | lastPt = pts[3]; |
| 610 | } break; |
| 611 | case SkPath::kClose_Verb: |
| 612 | pts[0] = lastPt; |
| 613 | pts[1] = firstPt; |
| 614 | if (SkPaint::kButt_Cap != capStyle && prevVerb == SkPath::kMove_Verb) { |
| 615 | // cap moveTo/close to match svg expectations for degenerate segments |
| 616 | extend_pts<capStyle>(prevVerb, iter.peek(), pts, 2); |
| 617 | } |
| 618 | lineproc(pts, 2, clip, blitter); |
| 619 | break; |
| 620 | case SkPath::kDone_Verb: |
| 621 | break; |
| 622 | } |
| 623 | if (SkPaint::kButt_Cap != capStyle) { |
| 624 | if (prevVerb == SkPath::kMove_Verb && |
| 625 | verb >= SkPath::kLine_Verb && verb <= SkPath::kCubic_Verb) { |
| 626 | firstPt = pts[0]; // the curve moved the initial point, so close to it instead |
| 627 | } |
| 628 | prevVerb = verb; |
| 629 | } |
| 630 | } |
| 631 | } |
| 632 | |
| 633 | void SkScan::HairPath(const SkPath& path, const SkRasterClip& clip, SkBlitter* blitter) { |
| 634 | hair_path<SkPaint::kButt_Cap>(path, clip, blitter, SkScan::HairLineRgn); |
| 635 | } |
| 636 | |
| 637 | void SkScan::AntiHairPath(const SkPath& path, const SkRasterClip& clip, SkBlitter* blitter) { |
| 638 | hair_path<SkPaint::kButt_Cap>(path, clip, blitter, SkScan::AntiHairLineRgn); |
| 639 | } |
| 640 | |
| 641 | void SkScan::HairSquarePath(const SkPath& path, const SkRasterClip& clip, SkBlitter* blitter) { |
| 642 | hair_path<SkPaint::kSquare_Cap>(path, clip, blitter, SkScan::HairLineRgn); |
| 643 | } |
| 644 | |
| 645 | void SkScan::AntiHairSquarePath(const SkPath& path, const SkRasterClip& clip, SkBlitter* blitter) { |
| 646 | hair_path<SkPaint::kSquare_Cap>(path, clip, blitter, SkScan::AntiHairLineRgn); |
| 647 | } |
| 648 | |
| 649 | void SkScan::HairRoundPath(const SkPath& path, const SkRasterClip& clip, SkBlitter* blitter) { |
| 650 | hair_path<SkPaint::kRound_Cap>(path, clip, blitter, SkScan::HairLineRgn); |
| 651 | } |
| 652 | |
| 653 | void SkScan::AntiHairRoundPath(const SkPath& path, const SkRasterClip& clip, SkBlitter* blitter) { |
| 654 | hair_path<SkPaint::kRound_Cap>(path, clip, blitter, SkScan::AntiHairLineRgn); |
| 655 | } |
| 656 | |
| 657 | /////////////////////////////////////////////////////////////////////////////// |
| 658 | |
| 659 | void SkScan::FrameRect(const SkRect& r, const SkPoint& strokeSize, |
| 660 | const SkRasterClip& clip, SkBlitter* blitter) { |
| 661 | SkASSERT(strokeSize.fX >= 0 && strokeSize.fY >= 0); |
| 662 | |
| 663 | if (strokeSize.fX < 0 || strokeSize.fY < 0) { |
| 664 | return; |
| 665 | } |
| 666 | |
| 667 | const SkScalar dx = strokeSize.fX; |
| 668 | const SkScalar dy = strokeSize.fY; |
| 669 | SkScalar rx = SkScalarHalf(dx); |
| 670 | SkScalar ry = SkScalarHalf(dy); |
| 671 | SkRect outer, tmp; |
| 672 | |
| 673 | outer.setLTRB(r.fLeft - rx, r.fTop - ry, r.fRight + rx, r.fBottom + ry); |
| 674 | |
| 675 | if (r.width() <= dx || r.height() <= dy) { |
| 676 | SkScan::FillRect(outer, clip, blitter); |
| 677 | return; |
| 678 | } |
| 679 | |
| 680 | tmp.setLTRB(outer.fLeft, outer.fTop, outer.fRight, outer.fTop + dy); |
| 681 | SkScan::FillRect(tmp, clip, blitter); |
| 682 | tmp.fTop = outer.fBottom - dy; |
| 683 | tmp.fBottom = outer.fBottom; |
| 684 | SkScan::FillRect(tmp, clip, blitter); |
| 685 | |
| 686 | tmp.setLTRB(outer.fLeft, outer.fTop + dy, outer.fLeft + dx, outer.fBottom - dy); |
| 687 | SkScan::FillRect(tmp, clip, blitter); |
| 688 | tmp.fLeft = outer.fRight - dx; |
| 689 | tmp.fRight = outer.fRight; |
| 690 | SkScan::FillRect(tmp, clip, blitter); |
| 691 | } |
| 692 | |
| 693 | void SkScan::HairLine(const SkPoint pts[], int count, const SkRasterClip& clip, |
| 694 | SkBlitter* blitter) { |
| 695 | if (clip.isBW()) { |
| 696 | HairLineRgn(pts, count, &clip.bwRgn(), blitter); |
| 697 | } else { |
| 698 | const SkRegion* clipRgn = nullptr; |
| 699 | |
| 700 | SkRect r; |
| 701 | r.setBounds(pts, count); |
| 702 | r.outset(SK_ScalarHalf, SK_ScalarHalf); |
| 703 | |
| 704 | SkAAClipBlitterWrapper wrap; |
| 705 | if (!clip.quickContains(r.roundOut())) { |
| 706 | wrap.init(clip, blitter); |
| 707 | blitter = wrap.getBlitter(); |
| 708 | clipRgn = &wrap.getRgn(); |
| 709 | } |
| 710 | HairLineRgn(pts, count, clipRgn, blitter); |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | void SkScan::AntiHairLine(const SkPoint pts[], int count, const SkRasterClip& clip, |
| 715 | SkBlitter* blitter) { |
| 716 | if (clip.isBW()) { |
| 717 | AntiHairLineRgn(pts, count, &clip.bwRgn(), blitter); |
| 718 | } else { |
| 719 | const SkRegion* clipRgn = nullptr; |
| 720 | |
| 721 | SkRect r; |
| 722 | r.setBounds(pts, count); |
| 723 | |
| 724 | SkAAClipBlitterWrapper wrap; |
| 725 | if (!clip.quickContains(r.roundOut().makeOutset(1, 1))) { |
| 726 | wrap.init(clip, blitter); |
| 727 | blitter = wrap.getBlitter(); |
| 728 | clipRgn = &wrap.getRgn(); |
| 729 | } |
| 730 | AntiHairLineRgn(pts, count, clipRgn, blitter); |
| 731 | } |
| 732 | } |
| 733 | |