blob: 97f0350db2574e1ecd058a43805c6a40e6b23e19 [file] [log] [blame]
/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkAddIntersections.h"
#include "SkOpCoincidence.h"
#include "SkOpEdgeBuilder.h"
#include "SkPathOpsCommon.h"
#include "SkPathWriter.h"
static bool bridgeWinding(SkOpContourHead* contourList, SkPathWriter* simple,
SkChunkAlloc* allocator, bool* closable) {
bool unsortable = false;
do {
SkOpSpan* span = FindSortableTop(contourList);
if (!span) {
break;
}
SkOpSegment* current = span->segment();
SkOpSpanBase* start = span->next();
SkOpSpanBase* end = span;
SkTDArray<SkOpSpanBase*> chase;
do {
if (current->activeWinding(start, end)) {
do {
if (!unsortable && current->done()) {
break;
}
SkASSERT(unsortable || !current->done());
SkOpSpanBase* nextStart = start;
SkOpSpanBase* nextEnd = end;
SkOpSegment* next = current->findNextWinding(&chase, &nextStart, &nextEnd,
&unsortable);
if (!next) {
if (!unsortable && simple->hasMove()
&& current->verb() != SkPath::kLine_Verb
&& !simple->isClosed()) {
if (!current->addCurveTo(start, end, simple)) {
return false;
}
#if DEBUG_ACTIVE_SPANS
if (!simple->isClosed()) {
DebugShowActiveSpans(contourList);
}
#endif
}
break;
}
#if DEBUG_FLOW
SkDebugf("%s current id=%d from=(%1.9g,%1.9g) to=(%1.9g,%1.9g)\n", __FUNCTION__,
current->debugID(), start->pt().fX, start->pt().fY,
end->pt().fX, end->pt().fY);
#endif
if (!current->addCurveTo(start, end, simple)) {
return false;
}
current = next;
start = nextStart;
end = nextEnd;
} while (!simple->isClosed() && (!unsortable || !start->starter(end)->done()));
if (current->activeWinding(start, end) && !simple->isClosed()) {
SkOpSpan* spanStart = start->starter(end);
if (!spanStart->done()) {
if (!current->addCurveTo(start, end, simple)) {
return false;
}
current->markDone(spanStart);
}
}
simple->close();
} else {
SkOpSpanBase* last = current->markAndChaseDone(start, end);
if (last && !last->chased()) {
last->setChased(true);
SkASSERT(!SkPathOpsDebug::ChaseContains(chase, last));
*chase.append() = last;
#if DEBUG_WINDING
SkDebugf("%s chase.append id=%d", __FUNCTION__, last->segment()->debugID());
if (!last->final()) {
SkDebugf(" windSum=%d", last->upCast()->windSum());
}
SkDebugf("\n");
#endif
}
}
current = FindChase(&chase, &start, &end);
#if DEBUG_ACTIVE_SPANS
DebugShowActiveSpans(contourList);
#endif
if (!current) {
break;
}
} while (true);
} while (true);
*closable = !simple->someAssemblyRequired();
return true;
}
// returns true if all edges were processed
static bool bridgeXor(SkOpContourHead* contourList, SkPathWriter* simple,
SkChunkAlloc* allocator, bool* closable) {
SkOpSegment* current;
SkOpSpanBase* start;
SkOpSpanBase* end;
bool unsortable = false;
*closable = true;
while ((current = FindUndone(contourList, &start, &end))) {
do {
#if DEBUG_ACTIVE_SPANS
if (!unsortable && current->done()) {
DebugShowActiveSpans(contourList);
}
#endif
SkASSERT(unsortable || !current->done());
SkOpSpanBase* nextStart = start;
SkOpSpanBase* nextEnd = end;
SkOpSegment* next = current->findNextXor(&nextStart, &nextEnd, &unsortable);
if (!next) {
if (!unsortable && simple->hasMove()
&& current->verb() != SkPath::kLine_Verb
&& !simple->isClosed()) {
if (!current->addCurveTo(start, end, simple)) {
return false;
}
#if DEBUG_ACTIVE_SPANS
if (!simple->isClosed()) {
DebugShowActiveSpans(contourList);
}
#endif
}
break;
}
#if DEBUG_FLOW
SkDebugf("%s current id=%d from=(%1.9g,%1.9g) to=(%1.9g,%1.9g)\n", __FUNCTION__,
current->debugID(), start->pt().fX, start->pt().fY,
end->pt().fX, end->pt().fY);
#endif
if (!current->addCurveTo(start, end, simple)) {
return false;
}
current = next;
start = nextStart;
end = nextEnd;
} while (!simple->isClosed() && (!unsortable || !start->starter(end)->done()));
if (!simple->isClosed()) {
SkASSERT(unsortable);
SkOpSpan* spanStart = start->starter(end);
if (!spanStart->done()) {
if (!current->addCurveTo(start, end, simple)) {
return false;
}
current->markDone(spanStart);
}
*closable = false;
}
simple->close();
#if DEBUG_ACTIVE_SPANS
DebugShowActiveSpans(contourList);
#endif
}
return true;
}
// FIXME : add this as a member of SkPath
bool Simplify(const SkPath& path, SkPath* result) {
SkChunkAlloc allocator(4096); // FIXME: constant-ize, tune
// returns 1 for evenodd, -1 for winding, regardless of inverse-ness
SkPath::FillType fillType = path.isInverseFillType() ? SkPath::kInverseEvenOdd_FillType
: SkPath::kEvenOdd_FillType;
if (path.isConvex()) {
if (result != &path) {
*result = path;
}
result->setFillType(fillType);
return true;
}
// turn path into list of segments
SkOpCoincidence coincidence;
SkOpContour contour;
SkOpContourHead* contourList = static_cast<SkOpContourHead*>(&contour);
SkOpGlobalState globalState(&coincidence, contourList SkDEBUGPARAMS(nullptr));
#if DEBUG_SORT
SkPathOpsDebug::gSortCount = SkPathOpsDebug::gSortCountDefault;
#endif
SkOpEdgeBuilder builder(path, &contour, &allocator, &globalState);
if (!builder.finish(&allocator)) {
return false;
}
#if DEBUG_DUMP_SEGMENTS
contour.dumpSegments();
#endif
if (!SortContourList(&contourList, false, false)) {
result->reset();
result->setFillType(fillType);
return true;
}
// find all intersections between segments
SkOpContour* current = contourList;
do {
SkOpContour* next = current;
while (AddIntersectTs(current, next, &coincidence, &allocator)
&& (next = next->next()));
} while ((current = current->next()));
#if DEBUG_VALIDATE
globalState.setPhase(SkOpGlobalState::kWalking);
#endif
if (!HandleCoincidence(contourList, &coincidence, &allocator)) {
return false;
}
#if DEBUG_DUMP_ALIGNMENT
contour.dumpSegments("aligned");
#endif
// construct closed contours
result->reset();
result->setFillType(fillType);
SkPathWriter wrapper(*result);
bool closable SK_INIT_TO_AVOID_WARNING;
if (builder.xorMask() == kWinding_PathOpsMask
? !bridgeWinding(contourList, &wrapper, &allocator, &closable)
: !bridgeXor(contourList, &wrapper, &allocator, &closable)) {
return false;
}
if (!closable)
{ // if some edges could not be resolved, assemble remaining fragments
SkPath temp;
temp.setFillType(fillType);
SkPathWriter assembled(temp);
Assemble(wrapper, &assembled);
*result = *assembled.nativePath();
result->setFillType(fillType);
}
return true;
}