blob: 2aff8c24e0a8461aee9575fa738ac16acf0ba1f6 [file] [log] [blame]
/*
* Copyright 2009 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.
*/
#ifndef SkEdgeClipper_DEFINED
#define SkEdgeClipper_DEFINED
#include "include/core/SkPath.h"
#include "include/core/SkPoint.h"
#include "include/core/SkScalar.h"
struct SkRect;
/** This is basically an iterator. It is initialized with an edge and a clip,
and then next() is called until it returns kDone_Verb.
*/
class SkEdgeClipper {
public:
SkEdgeClipper(bool canCullToTheRight) : fCanCullToTheRight(canCullToTheRight) {}
bool clipLine(SkPoint p0, SkPoint p1, const SkRect& clip);
bool clipQuad(const SkPoint pts[3], const SkRect& clip);
bool clipCubic(const SkPoint pts[4], const SkRect& clip);
SkPath::Verb next(SkPoint pts[]);
bool canCullToTheRight() const { return fCanCullToTheRight; }
/**
* Clips each segment from the path, and passes the result (in a clipper) to the
* consume proc.
*/
static void ClipPath(const SkPath& path, const SkRect& clip, bool canCullToTheRight,
void (*consume)(SkEdgeClipper*, bool newCtr, void* ctx), void* ctx);
private:
SkPoint* fCurrPoint;
SkPath::Verb* fCurrVerb;
const bool fCanCullToTheRight;
enum {
kMaxVerbs = 18, // max curvature in X and Y split cubic into 9 pieces, * (line + cubic)
kMaxPoints = 54 // 2 lines + 1 cubic require 6 points; times 9 pieces
};
SkPoint fPoints[kMaxPoints];
SkPath::Verb fVerbs[kMaxVerbs];
void clipMonoQuad(const SkPoint srcPts[3], const SkRect& clip);
void clipMonoCubic(const SkPoint srcPts[4], const SkRect& clip);
void appendLine(SkPoint p0, SkPoint p1);
void appendVLine(SkScalar x, SkScalar y0, SkScalar y1, bool reverse);
void appendQuad(const SkPoint pts[3], bool reverse);
void appendCubic(const SkPoint pts[4], bool reverse);
};
#ifdef SK_DEBUG
void sk_assert_monotonic_x(const SkPoint pts[], int count);
void sk_assert_monotonic_y(const SkPoint pts[], int count);
#else
#define sk_assert_monotonic_x(pts, count)
#define sk_assert_monotonic_y(pts, count)
#endif
#endif