The Tor Browser: gfx/skia/trunk/src/core/SkScan_Path.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkScan_Path.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkScan_Path.cpp

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkScanPriv.h"
 #include "SkBlitter.h"
 #include "SkEdge.h"
 #include "SkEdgeBuilder.h"
 #include "SkGeometry.h"
 #include "SkPath.h"
 #include "SkQuadClipper.h"
 #include "SkRasterClip.h"
 #include "SkRegion.h"
 #include "SkTemplates.h"
 #include "SkTSort.h"
 #ifdef SK_USE_LEGACY_AA_COVERAGE
     #define SK_USE_STD_SORT_FOR_EDGES
 #endif
 #define kEDGE_HEAD_Y    SK_MinS32
 #define kEDGE_TAIL_Y    SK_MaxS32
 #ifdef SK_DEBUG
     static void validate_sort(const SkEdge* edge) {
         int y = kEDGE_HEAD_Y;
         while (edge->fFirstY != SK_MaxS32) {
             edge->validate();
             SkASSERT(y <= edge->fFirstY);
             y = edge->fFirstY;
             edge = edge->fNext;
         }
     }
 #else
     #define validate_sort(edge)
 #endif
 static inline void remove_edge(SkEdge* edge) {
     edge->fPrev->fNext = edge->fNext;
     edge->fNext->fPrev = edge->fPrev;
 }
 static inline void swap_edges(SkEdge* prev, SkEdge* next) {
     SkASSERT(prev->fNext == next && next->fPrev == prev);
     // remove prev from the list
     prev->fPrev->fNext = next;
     next->fPrev = prev->fPrev;
     // insert prev after next
     prev->fNext = next->fNext;
     next->fNext->fPrev = prev;
     next->fNext = prev;
     prev->fPrev = next;
 }
 static void backward_insert_edge_based_on_x(SkEdge* edge SkDECLAREPARAM(int, curr_y)) {
     SkFixed x = edge->fX;
     for (;;) {
         SkEdge* prev = edge->fPrev;
         // add 1 to curr_y since we may have added new edges (built from curves)
         // that start on the next scanline
         SkASSERT(prev && prev->fFirstY <= curr_y + 1);
         if (prev->fX <= x) {
             break;
         }
         swap_edges(prev, edge);
     }
 }
 static void insert_new_edges(SkEdge* newEdge, int curr_y) {
     SkASSERT(newEdge->fFirstY >= curr_y);
     while (newEdge->fFirstY == curr_y) {
         SkEdge* next = newEdge->fNext;
         backward_insert_edge_based_on_x(newEdge  SkPARAM(curr_y));
         newEdge = next;
     }
 }
 #ifdef SK_DEBUG
 static void validate_edges_for_y(const SkEdge* edge, int curr_y) {
     while (edge->fFirstY <= curr_y) {
         SkASSERT(edge->fPrev && edge->fNext);
         SkASSERT(edge->fPrev->fNext == edge);
         SkASSERT(edge->fNext->fPrev == edge);
         SkASSERT(edge->fFirstY <= edge->fLastY);
         SkASSERT(edge->fPrev->fX <= edge->fX);
         edge = edge->fNext;
     }
 }
 #else
     #define validate_edges_for_y(edge, curr_y)
 #endif
 #if defined _WIN32 && _MSC_VER >= 1300  // disable warning : local variable used without having been initialized
 #pragma warning ( push )
 #pragma warning ( disable : 4701 )
 #endif
 typedef void (*PrePostProc)(SkBlitter* blitter, int y, bool isStartOfScanline);
 #define PREPOST_START   true
 #define PREPOST_END     false
 static void walk_edges(SkEdge* prevHead, SkPath::FillType fillType,
                        SkBlitter* blitter, int start_y, int stop_y,
                        PrePostProc proc) {
     validate_sort(prevHead->fNext);
     int curr_y = start_y;
     // returns 1 for evenodd, -1 for winding, regardless of inverse-ness
     int windingMask = (fillType & 1) ? 1 : -1;
     for (;;) {
         int     w = 0;
         int     left SK_INIT_TO_AVOID_WARNING;
         bool    in_interval = false;
         SkEdge* currE = prevHead->fNext;
         SkFixed prevX = prevHead->fX;
         validate_edges_for_y(currE, curr_y);
         if (proc) {
             proc(blitter, curr_y, PREPOST_START);    // pre-proc
         }
         while (currE->fFirstY <= curr_y) {
             SkASSERT(currE->fLastY >= curr_y);
             int x = SkFixedRoundToInt(currE->fX);
             w += currE->fWinding;
             if ((w & windingMask) == 0) { // we finished an interval
                 SkASSERT(in_interval);
                 int width = x - left;
                 SkASSERT(width >= 0);
                 if (width)
                     blitter->blitH(left, curr_y, width);
                 in_interval = false;
             } else if (!in_interval) {
                 left = x;
                 in_interval = true;
             }
             SkEdge* next = currE->fNext;
             SkFixed newX;
             if (currE->fLastY == curr_y) {    // are we done with this edge?
                 if (currE->fCurveCount < 0) {
                     if (((SkCubicEdge*)currE)->updateCubic()) {
                         SkASSERT(currE->fFirstY == curr_y + 1);
                         newX = currE->fX;
                         goto NEXT_X;
                     }
                 } else if (currE->fCurveCount > 0) {
                     if (((SkQuadraticEdge*)currE)->updateQuadratic()) {
                         newX = currE->fX;
                         goto NEXT_X;
                     }
                 }
                 remove_edge(currE);
             } else {
                 SkASSERT(currE->fLastY > curr_y);
                 newX = currE->fX + currE->fDX;
                 currE->fX = newX;
             NEXT_X:
                 if (newX < prevX) { // ripple currE backwards until it is x-sorted
                     backward_insert_edge_based_on_x(currE  SkPARAM(curr_y));
                 } else {
                     prevX = newX;
                 }
             }
             currE = next;
             SkASSERT(currE);
         }
         if (proc) {
             proc(blitter, curr_y, PREPOST_END);    // post-proc
         }
         curr_y += 1;
         if (curr_y >= stop_y) {
             break;
         }
         // now currE points to the first edge with a Yint larger than curr_y
         insert_new_edges(currE, curr_y);
     }
 }
 // return true if we're done with this edge
 static bool update_edge(SkEdge* edge, int last_y) {
     SkASSERT(edge->fLastY >= last_y);
     if (last_y == edge->fLastY) {
         if (edge->fCurveCount < 0) {
             if (((SkCubicEdge*)edge)->updateCubic()) {
                 SkASSERT(edge->fFirstY == last_y + 1);
                 return false;
             }
         } else if (edge->fCurveCount > 0) {
             if (((SkQuadraticEdge*)edge)->updateQuadratic()) {
                 SkASSERT(edge->fFirstY == last_y + 1);
                 return false;
             }
         }
         return true;
     }
     return false;
 }
 static void walk_convex_edges(SkEdge* prevHead, SkPath::FillType,
                               SkBlitter* blitter, int start_y, int stop_y,
                               PrePostProc proc) {
     validate_sort(prevHead->fNext);
     SkEdge* leftE = prevHead->fNext;
     SkEdge* riteE = leftE->fNext;
     SkEdge* currE = riteE->fNext;
 #if 0
     int local_top = leftE->fFirstY;
     SkASSERT(local_top == riteE->fFirstY);
 #else
     // our edge choppers for curves can result in the initial edges
     // not lining up, so we take the max.
     int local_top = SkMax32(leftE->fFirstY, riteE->fFirstY);
 #endif
     SkASSERT(local_top >= start_y);
     for (;;) {
         SkASSERT(leftE->fFirstY <= stop_y);
         SkASSERT(riteE->fFirstY <= stop_y);
         if (leftE->fX > riteE->fX || (leftE->fX == riteE->fX &&
                                       leftE->fDX > riteE->fDX)) {
             SkTSwap(leftE, riteE);
         }
         int local_bot = SkMin32(leftE->fLastY, riteE->fLastY);
         local_bot = SkMin32(local_bot, stop_y - 1);
         SkASSERT(local_top <= local_bot);
         SkFixed left = leftE->fX;
         SkFixed dLeft = leftE->fDX;
         SkFixed rite = riteE->fX;
         SkFixed dRite = riteE->fDX;
         int count = local_bot - local_top;
         SkASSERT(count >= 0);
         if (0 == (dLeft | dRite)) {
             int L = SkFixedRoundToInt(left);
             int R = SkFixedRoundToInt(rite);
             if (L < R) {
                 count += 1;
                 blitter->blitRect(L, local_top, R - L, count);
                 left += count * dLeft;
                 rite += count * dRite;
             }
             local_top = local_bot + 1;
         } else {
             do {
                 int L = SkFixedRoundToInt(left);
                 int R = SkFixedRoundToInt(rite);
                 if (L < R) {
                     blitter->blitH(L, local_top, R - L);
                 }
                 left += dLeft;
                 rite += dRite;
                 local_top += 1;
             } while (--count >= 0);
         }
         leftE->fX = left;
         riteE->fX = rite;
         if (update_edge(leftE, local_bot)) {
             if (currE->fFirstY >= stop_y) {
                 break;
             }
             leftE = currE;
             currE = currE->fNext;
         }
         if (update_edge(riteE, local_bot)) {
             if (currE->fFirstY >= stop_y) {
                 break;
             }
             riteE = currE;
             currE = currE->fNext;
         }
         SkASSERT(leftE);
         SkASSERT(riteE);
         // check our bottom clip
         SkASSERT(local_top == local_bot + 1);
         if (local_top >= stop_y) {
             break;
         }
     }
 }
 ///////////////////////////////////////////////////////////////////////////////
 // this guy overrides blitH, and will call its proxy blitter with the inverse
 // of the spans it is given (clipped to the left/right of the cliprect)
 //
 // used to implement inverse filltypes on paths
 //
 class InverseBlitter : public SkBlitter {
 public:
     void setBlitter(SkBlitter* blitter, const SkIRect& clip, int shift) {
         fBlitter = blitter;
         fFirstX = clip.fLeft << shift;
         fLastX = clip.fRight << shift;
     }
     void prepost(int y, bool isStart) {
         if (isStart) {
             fPrevX = fFirstX;
         } else {
             int invWidth = fLastX - fPrevX;
             if (invWidth > 0) {
                 fBlitter->blitH(fPrevX, y, invWidth);
             }
         }
     }
     // overrides
     virtual void blitH(int x, int y, int width) {
         int invWidth = x - fPrevX;
         if (invWidth > 0) {
             fBlitter->blitH(fPrevX, y, invWidth);
         }
         fPrevX = x + width;
     }
     // we do not expect to get called with these entrypoints
     virtual void blitAntiH(int, int, const SkAlpha[], const int16_t runs[]) {
         SkDEBUGFAIL("blitAntiH unexpected");
     }
     virtual void blitV(int x, int y, int height, SkAlpha alpha) {
         SkDEBUGFAIL("blitV unexpected");
     }
     virtual void blitRect(int x, int y, int width, int height) {
         SkDEBUGFAIL("blitRect unexpected");
     }
     virtual void blitMask(const SkMask&, const SkIRect& clip) {
         SkDEBUGFAIL("blitMask unexpected");
     }
     virtual const SkBitmap* justAnOpaqueColor(uint32_t* value) {
         SkDEBUGFAIL("justAnOpaqueColor unexpected");
         return NULL;
     }
 private:
     SkBlitter*  fBlitter;
     int         fFirstX, fLastX, fPrevX;
 };
 static void PrePostInverseBlitterProc(SkBlitter* blitter, int y, bool isStart) {
     ((InverseBlitter*)blitter)->prepost(y, isStart);
 }
 ///////////////////////////////////////////////////////////////////////////////
 #if defined _WIN32 && _MSC_VER >= 1300
 #pragma warning ( pop )
 #endif
 #ifdef SK_USE_STD_SORT_FOR_EDGES
 extern "C" {
     static int edge_compare(const void* a, const void* b) {
         const SkEdge* edgea = *(const SkEdge**)a;
         const SkEdge* edgeb = *(const SkEdge**)b;
         int valuea = edgea->fFirstY;
         int valueb = edgeb->fFirstY;
         if (valuea == valueb) {
             valuea = edgea->fX;
             valueb = edgeb->fX;
         }
         // this overflows if valuea >>> valueb or vice-versa
         //     return valuea - valueb;
         // do perform the slower but safe compares
         return (valuea < valueb) ? -1 : (valuea > valueb);
     }
 }
 #else
 static bool operator<(const SkEdge& a, const SkEdge& b) {
     int valuea = a.fFirstY;
     int valueb = b.fFirstY;
     if (valuea == valueb) {
         valuea = a.fX;
         valueb = b.fX;
     }
     return valuea < valueb;
 }
 #endif
 static SkEdge* sort_edges(SkEdge* list[], int count, SkEdge** last) {
 #ifdef SK_USE_STD_SORT_FOR_EDGES
     qsort(list, count, sizeof(SkEdge*), edge_compare);
 #else
     SkTQSort(list, list + count - 1);
 #endif
     // now make the edges linked in sorted order
     for (int i = 1; i < count; i++) {
         list[i - 1]->fNext = list[i];
         list[i]->fPrev = list[i - 1];
     }
     *last = list[count - 1];
     return list[0];
 }
 // clipRect may be null, even though we always have a clip. This indicates that
 // the path is contained in the clip, and so we can ignore it during the blit
 //
 // clipRect (if no null) has already been shifted up
 //
 void sk_fill_path(const SkPath& path, const SkIRect* clipRect, SkBlitter* blitter,
                   int start_y, int stop_y, int shiftEdgesUp,
                   const SkRegion& clipRgn) {
     SkASSERT(&path && blitter);
     SkEdgeBuilder   builder;
     int count = builder.build(path, clipRect, shiftEdgesUp);
     SkEdge**    list = builder.edgeList();
     if (count < 2) {
         if (path.isInverseFillType()) {
             /*
              *  Since we are in inverse-fill, our caller has already drawn above
              *  our top (start_y) and will draw below our bottom (stop_y). Thus
              *  we need to restrict our drawing to the intersection of the clip
              *  and those two limits.
              */
             SkIRect rect = clipRgn.getBounds();
             if (rect.fTop < start_y) {
                 rect.fTop = start_y;
             }
             if (rect.fBottom > stop_y) {
                 rect.fBottom = stop_y;
             }
             if (!rect.isEmpty()) {
                 blitter->blitRect(rect.fLeft << shiftEdgesUp,
                                   rect.fTop << shiftEdgesUp,
                                   rect.width() << shiftEdgesUp,
                                   rect.height() << shiftEdgesUp);
             }
         }
         return;
     }
     SkEdge headEdge, tailEdge, *last;
     // this returns the first and last edge after they're sorted into a dlink list
     SkEdge* edge = sort_edges(list, count, &last);
     headEdge.fPrev = NULL;
     headEdge.fNext = edge;
     headEdge.fFirstY = kEDGE_HEAD_Y;
     headEdge.fX = SK_MinS32;
     edge->fPrev = &headEdge;
     tailEdge.fPrev = last;
     tailEdge.fNext = NULL;
     tailEdge.fFirstY = kEDGE_TAIL_Y;
     last->fNext = &tailEdge;
     // now edge is the head of the sorted linklist
     start_y <<= shiftEdgesUp;
     stop_y <<= shiftEdgesUp;
     if (clipRect && start_y < clipRect->fTop) {
         start_y = clipRect->fTop;
     }
     if (clipRect && stop_y > clipRect->fBottom) {
         stop_y = clipRect->fBottom;
     }
     InverseBlitter  ib;
     PrePostProc     proc = NULL;
     if (path.isInverseFillType()) {
         ib.setBlitter(blitter, clipRgn.getBounds(), shiftEdgesUp);
         blitter = &ib;
         proc = PrePostInverseBlitterProc;
     }
     if (path.isConvex() && (NULL == proc)) {
         walk_convex_edges(&headEdge, path.getFillType(), blitter, start_y, stop_y, NULL);
     } else {
         walk_edges(&headEdge, path.getFillType(), blitter, start_y, stop_y, proc);
     }
 }
 void sk_blit_above(SkBlitter* blitter, const SkIRect& ir, const SkRegion& clip) {
     const SkIRect& cr = clip.getBounds();
     SkIRect tmp;
     tmp.fLeft = cr.fLeft;
     tmp.fRight = cr.fRight;
     tmp.fTop = cr.fTop;
     tmp.fBottom = ir.fTop;
     if (!tmp.isEmpty()) {
         blitter->blitRectRegion(tmp, clip);
     }
 }
 void sk_blit_below(SkBlitter* blitter, const SkIRect& ir, const SkRegion& clip) {
     const SkIRect& cr = clip.getBounds();
     SkIRect tmp;
     tmp.fLeft = cr.fLeft;
     tmp.fRight = cr.fRight;
     tmp.fTop = ir.fBottom;
     tmp.fBottom = cr.fBottom;
     if (!tmp.isEmpty()) {
         blitter->blitRectRegion(tmp, clip);
     }
 }
 ///////////////////////////////////////////////////////////////////////////////
 /**
  *  If the caller is drawing an inverse-fill path, then it pass true for
  *  skipRejectTest, so we don't abort drawing just because the src bounds (ir)
  *  is outside of the clip.
  */
 SkScanClipper::SkScanClipper(SkBlitter* blitter, const SkRegion* clip,
                              const SkIRect& ir, bool skipRejectTest) {
     fBlitter = NULL;     // null means blit nothing
     fClipRect = NULL;
     if (clip) {
         fClipRect = &clip->getBounds();
         if (!skipRejectTest && !SkIRect::Intersects(*fClipRect, ir)) { // completely clipped out
             return;
         }
         if (clip->isRect()) {
             if (fClipRect->contains(ir)) {
                 fClipRect = NULL;
             } else {
                 // only need a wrapper blitter if we're horizontally clipped
                 if (fClipRect->fLeft > ir.fLeft || fClipRect->fRight < ir.fRight) {
                     fRectBlitter.init(blitter, *fClipRect);
                     blitter = &fRectBlitter;
                 }
             }
         } else {
             fRgnBlitter.init(blitter, clip);
             blitter = &fRgnBlitter;
         }
     }
     fBlitter = blitter;
 }
 ///////////////////////////////////////////////////////////////////////////////
 static bool clip_to_limit(const SkRegion& orig, SkRegion* reduced) {
     const int32_t limit = 32767;
     SkIRect limitR;
     limitR.set(-limit, -limit, limit, limit);
     if (limitR.contains(orig.getBounds())) {
         return false;
     }
     reduced->op(orig, limitR, SkRegion::kIntersect_Op);
     return true;
 }
 void SkScan::FillPath(const SkPath& path, const SkRegion& origClip,
                       SkBlitter* blitter) {
     if (origClip.isEmpty()) {
         return;
     }
     // Our edges are fixed-point, and don't like the bounds of the clip to
     // exceed that. Here we trim the clip just so we don't overflow later on
     const SkRegion* clipPtr = &origClip;
     SkRegion finiteClip;
     if (clip_to_limit(origClip, &finiteClip)) {
         if (finiteClip.isEmpty()) {
             return;
         }
         clipPtr = &finiteClip;
     }
         // don't reference "origClip" any more, just use clipPtr
     SkIRect ir;
     path.getBounds().roundOut(&ir);
     if (ir.isEmpty()) {
         if (path.isInverseFillType()) {
             blitter->blitRegion(*clipPtr);
         }
         return;
     }
     SkScanClipper clipper(blitter, clipPtr, ir, path.isInverseFillType());
     blitter = clipper.getBlitter();
     if (blitter) {
         // we have to keep our calls to blitter in sorted order, so we
         // must blit the above section first, then the middle, then the bottom.
         if (path.isInverseFillType()) {
             sk_blit_above(blitter, ir, *clipPtr);
         }
         sk_fill_path(path, clipper.getClipRect(), blitter, ir.fTop, ir.fBottom,
 , *clipPtr);
         if (path.isInverseFillType()) {
             sk_blit_below(blitter, ir, *clipPtr);
         }
     } else {
         // what does it mean to not have a blitter if path.isInverseFillType???
     }
 }
 void SkScan::FillPath(const SkPath& path, const SkIRect& ir,
                       SkBlitter* blitter) {
     SkRegion rgn(ir);
     FillPath(path, rgn, blitter);
 }
 ///////////////////////////////////////////////////////////////////////////////
 static int build_tri_edges(SkEdge edge[], const SkPoint pts[],
                            const SkIRect* clipRect, SkEdge* list[]) {
     SkEdge** start = list;
     if (edge->setLine(pts[0], pts[1], clipRect, 0)) {
         *list++ = edge;
         edge = (SkEdge*)((char*)edge + sizeof(SkEdge));
     }
     if (edge->setLine(pts[1], pts[2], clipRect, 0)) {
         *list++ = edge;
         edge = (SkEdge*)((char*)edge + sizeof(SkEdge));
     }
     if (edge->setLine(pts[2], pts[0], clipRect, 0)) {
         *list++ = edge;
     }
     return (int)(list - start);
 }
 static void sk_fill_triangle(const SkPoint pts[], const SkIRect* clipRect,
                              SkBlitter* blitter, const SkIRect& ir) {
     SkASSERT(pts && blitter);
     SkEdge edgeStorage[3];
     SkEdge* list[3];
     int count = build_tri_edges(edgeStorage, pts, clipRect, list);
     if (count < 2) {
         return;
     }
     SkEdge headEdge, tailEdge, *last;
     // this returns the first and last edge after they're sorted into a dlink list
     SkEdge* edge = sort_edges(list, count, &last);
     headEdge.fPrev = NULL;
     headEdge.fNext = edge;
     headEdge.fFirstY = kEDGE_HEAD_Y;
     headEdge.fX = SK_MinS32;
     edge->fPrev = &headEdge;
     tailEdge.fPrev = last;
     tailEdge.fNext = NULL;
     tailEdge.fFirstY = kEDGE_TAIL_Y;
     last->fNext = &tailEdge;
     // now edge is the head of the sorted linklist
     int stop_y = ir.fBottom;
     if (clipRect && stop_y > clipRect->fBottom) {
         stop_y = clipRect->fBottom;
     }
     int start_y = ir.fTop;
     if (clipRect && start_y < clipRect->fTop) {
         start_y = clipRect->fTop;
     }
     walk_convex_edges(&headEdge, SkPath::kEvenOdd_FillType, blitter, start_y, stop_y, NULL);
 //    walk_edges(&headEdge, SkPath::kEvenOdd_FillType, blitter, start_y, stop_y, NULL);
 }
 void SkScan::FillTriangle(const SkPoint pts[], const SkRasterClip& clip,
                           SkBlitter* blitter) {
     if (clip.isEmpty()) {
         return;
     }
     SkRect  r;
     SkIRect ir;
     r.set(pts, 3);
     r.round(&ir);
     if (ir.isEmpty() || !SkIRect::Intersects(ir, clip.getBounds())) {
         return;
     }
     SkAAClipBlitterWrapper wrap;
     const SkRegion* clipRgn;
     if (clip.isBW()) {
         clipRgn = &clip.bwRgn();
     } else {
         wrap.init(clip, blitter);
         clipRgn = &wrap.getRgn();
         blitter = wrap.getBlitter();
     }
     SkScanClipper clipper(blitter, clipRgn, ir);
     blitter = clipper.getBlitter();
     if (NULL != blitter) {
         sk_fill_triangle(pts, clipper.getClipRect(), blitter, ir);
     }
 }

The Tor Browser / annotate

gfx/skia/trunk/src/core/SkScan_Path.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkScan_Path.cpp