fix path op conic bugs

tests/SubsetPath.cpp

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SubsetPath.h"
+
+SubsetPath::SubsetPath(const SkPath& path)
+        : fPath(path)
+        , fSubset(1) {
+}
+
+int SubsetPath::range(int* end) const {
+    int leadingZero = SkCLZ(fSubset);
+    int parts = 1 << (31 - leadingZero);
+    int partIndex = fSubset - parts;
+    SkASSERT(partIndex >= 0);
+    int count = fSelected.count();
+    int start = count * partIndex / parts;
+    *end = count * (partIndex + 1) / parts;
+    return start;
+}
+
+bool SubsetPath::subset(bool testFailed, SkPath* sub) {
+    int start, end;
+    if (!testFailed) {
+        start = range(&end);
+        for (; start < end; ++start) {
+            fSelected[start] = true;
+        }
+    }
+    do {
+        do {
+            ++fSubset;
+            start = range(&end);
+ //           SkDebugf("%d s=%d e=%d t=%d\n", fSubset, start, end, fTries);
+            if (end - start > 1) {
+                fTries = fSelected.count();
+            } else if (end - start == 1) {
+                if (--fTries <= 0) {
+                    return false;
+                }
+            }
+        } while (start == end);
+    } while (!fSelected[start]);
+    for (; start < end; ++start) {
+        fSelected[start] = false;
+    }
+#if 1
+    SkDebugf("selected: ");
+    for (int index = 0; index < fSelected.count(); ++index) {
+        SkDebugf("%c", fSelected[index] ? 'x' : '-');
+    }
+#endif
+    *sub = getSubsetPath();
+    return true;
+}
+
+SubsetContours::SubsetContours(const SkPath& path)
+        : SubsetPath(path) {
+    SkPath::RawIter iter(fPath);
+    uint8_t verb;
+    SkPoint pts[4];
+    bool foundCurve = false;
+    int contourCount = 0;
+    while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
+        switch (verb) {
+            case SkPath::kMove_Verb:
+                break;
+            case SkPath::kLine_Verb:
+            case SkPath::kQuad_Verb:
+            case SkPath::kConic_Verb:
+            case SkPath::kCubic_Verb:
+                foundCurve = true;
+                break;
+            case SkPath::kClose_Verb:
+                ++contourCount;
+                foundCurve = false;
+                break;
+            default:
+                SkDEBUGFAIL("bad verb");
+                return;
+        }
+    }
+    contourCount += foundCurve;
+    for (int index = 0; index < contourCount; ++index) {
+        *fSelected.append() = true;
+    }
+    fTries = contourCount;
+}
+
+SkPath SubsetContours::getSubsetPath() const {
+    SkPath result;
+    result.setFillType(fPath.getFillType());
+    if (!fSelected.count()) {
+        return result;
+    }
+    SkPath::RawIter iter(fPath);
+    uint8_t verb;
+    SkPoint pts[4];
+    int contourCount = 0;
+    bool enabled = fSelected[0];
+    bool addMoveTo = true;
+    while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
+        if (enabled && addMoveTo) {
+            result.moveTo(pts[0]);
+            addMoveTo = false;
+        }
+        switch (verb) {
+            case SkPath::kMove_Verb:
+                break;
+            case SkPath::kLine_Verb:
+                if (enabled) {
+                    result.lineTo(pts[1]);
+                }
+                break;
+            case SkPath::kQuad_Verb:
+                if (enabled) {
+                    result.quadTo(pts[1], pts[2]);
+                }
+                break;
+            case SkPath::kConic_Verb:
+                if (enabled) {
+                    result.conicTo(pts[1], pts[2], iter.conicWeight());
+                }
+                break;
+            case SkPath::kCubic_Verb:
+                 if (enabled) {
+                    result.cubicTo(pts[1], pts[2], pts[3]);
+                }
+                break;
+            case SkPath::kClose_Verb:
+                if (enabled) {
+                    result.close();
+                }
+                if (++contourCount >= fSelected.count()) {
+                    break;
+                }
+                enabled = fSelected[contourCount];
+                addMoveTo = true;
+                continue;
+            default:
+                SkDEBUGFAIL("bad verb");
+                return result;
+        }
+    }
+    return result;
+}
+
+SubsetVerbs::SubsetVerbs(const SkPath& path)
+        : SubsetPath(path) {
+    SkPath::RawIter iter(fPath);
+    uint8_t verb;
+    SkPoint pts[4];
+    int verbCount = 0;
+    while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
+        switch (verb) {
+            case SkPath::kMove_Verb:
+                break;
+            case SkPath::kLine_Verb:
+            case SkPath::kQuad_Verb:
+            case SkPath::kConic_Verb:
+            case SkPath::kCubic_Verb:
+                ++verbCount;
+                break;
+            case SkPath::kClose_Verb:
+                break;
+            default:
+                SkDEBUGFAIL("bad verb");
+                return;
+        }
+    }
+    for (int index = 0; index < verbCount; ++index) {
+        *fSelected.append() = true;
+    }
+    fTries = verbCount;
+}
+
+SkPath SubsetVerbs::getSubsetPath() const {
+    SkPath result;
+    result.setFillType(fPath.getFillType());
+    if (!fSelected.count()) {
+        return result;
+    }
+    SkPath::RawIter iter(fPath);
+    uint8_t verb;
+    SkPoint pts[4];
+    int verbIndex = 0;
+    bool addMoveTo = true;
+    bool addLineTo = false;
+    while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
+        bool enabled = SkPath::kLine_Verb <= verb && verb <= SkPath::kCubic_Verb
+            ? fSelected[verbIndex++] : false;
+        if (enabled) {
+            if (addMoveTo) {
+                result.moveTo(pts[0]);
+                addMoveTo = false;
+            } else if (addLineTo) {
+                result.lineTo(pts[0]);
+                addLineTo = false;
+            }
+        }
+        switch (verb) {
+            case SkPath::kMove_Verb:
+                break;
+            case SkPath::kLine_Verb:
+                if (enabled) {
+                    result.lineTo(pts[1]);
+                }
+                break;
+            case SkPath::kQuad_Verb:
+                if (enabled) {
+                    result.quadTo(pts[1], pts[2]);
+                }
+                break;
+            case SkPath::kConic_Verb:
+                if (enabled) {
+                    result.conicTo(pts[1], pts[2], iter.conicWeight());
+                }
+                break;
+            case SkPath::kCubic_Verb:
+                 if (enabled) {
+                    result.cubicTo(pts[1], pts[2], pts[3]);
+                }
+                break;
+            case SkPath::kClose_Verb:
+                result.close();
+                addMoveTo = true;
+                addLineTo = false;
+                continue;
+            default:
+                SkDEBUGFAIL("bad verb");
+                return result;
+        }
+        addLineTo = !enabled;
+    }
+    return result;
+}