1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/include/core/SkPathMeasure.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,109 @@
1.4 +/*
1.5 + * Copyright 2006 The Android Open Source Project
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#ifndef SkPathMeasure_DEFINED
1.12 +#define SkPathMeasure_DEFINED
1.13 +
1.14 +#include "SkPath.h"
1.15 +#include "SkTDArray.h"
1.16 +
1.17 +class SK_API SkPathMeasure : SkNoncopyable {
1.18 +public:
1.19 + SkPathMeasure();
1.20 + /** Initialize the pathmeasure with the specified path. The path must remain valid
1.21 + for the lifetime of the measure object, or until setPath() is called with
1.22 + a different path (or null), since the measure object keeps a pointer to the
1.23 + path object (does not copy its data).
1.24 + */
1.25 + SkPathMeasure(const SkPath& path, bool forceClosed);
1.26 + ~SkPathMeasure();
1.27 +
1.28 + /** Reset the pathmeasure with the specified path. The path must remain valid
1.29 + for the lifetime of the measure object, or until setPath() is called with
1.30 + a different path (or null), since the measure object keeps a pointer to the
1.31 + path object (does not copy its data).
1.32 + */
1.33 + void setPath(const SkPath*, bool forceClosed);
1.34 +
1.35 + /** Return the total length of the current contour, or 0 if no path
1.36 + is associated (e.g. resetPath(null))
1.37 + */
1.38 + SkScalar getLength();
1.39 +
1.40 + /** Pins distance to 0 <= distance <= getLength(), and then computes
1.41 + the corresponding position and tangent.
1.42 + Returns false if there is no path, or a zero-length path was specified, in which case
1.43 + position and tangent are unchanged.
1.44 + */
1.45 + bool SK_WARN_UNUSED_RESULT getPosTan(SkScalar distance, SkPoint* position,
1.46 + SkVector* tangent);
1.47 +
1.48 + enum MatrixFlags {
1.49 + kGetPosition_MatrixFlag = 0x01,
1.50 + kGetTangent_MatrixFlag = 0x02,
1.51 + kGetPosAndTan_MatrixFlag = kGetPosition_MatrixFlag | kGetTangent_MatrixFlag
1.52 + };
1.53 +
1.54 + /** Pins distance to 0 <= distance <= getLength(), and then computes
1.55 + the corresponding matrix (by calling getPosTan).
1.56 + Returns false if there is no path, or a zero-length path was specified, in which case
1.57 + matrix is unchanged.
1.58 + */
1.59 + bool SK_WARN_UNUSED_RESULT getMatrix(SkScalar distance, SkMatrix* matrix,
1.60 + MatrixFlags flags = kGetPosAndTan_MatrixFlag);
1.61 +
1.62 + /** Given a start and stop distance, return in dst the intervening segment(s).
1.63 + If the segment is zero-length, return false, else return true.
1.64 + startD and stopD are pinned to legal values (0..getLength()). If startD <= stopD
1.65 + then return false (and leave dst untouched).
1.66 + Begin the segment with a moveTo if startWithMoveTo is true
1.67 + */
1.68 + bool getSegment(SkScalar startD, SkScalar stopD, SkPath* dst, bool startWithMoveTo);
1.69 +
1.70 + /** Return true if the current contour is closed()
1.71 + */
1.72 + bool isClosed();
1.73 +
1.74 + /** Move to the next contour in the path. Return true if one exists, or false if
1.75 + we're done with the path.
1.76 + */
1.77 + bool nextContour();
1.78 +
1.79 +#ifdef SK_DEBUG
1.80 + void dump();
1.81 +#endif
1.82 +
1.83 +private:
1.84 + SkPath::Iter fIter;
1.85 + const SkPath* fPath;
1.86 + SkScalar fLength; // relative to the current contour
1.87 + int fFirstPtIndex; // relative to the current contour
1.88 + bool fIsClosed; // relative to the current contour
1.89 + bool fForceClosed;
1.90 +
1.91 + struct Segment {
1.92 + SkScalar fDistance; // total distance up to this point
1.93 + unsigned fPtIndex : 15; // index into the fPts array
1.94 + unsigned fTValue : 15;
1.95 + unsigned fType : 2;
1.96 +
1.97 + SkScalar getScalarT() const;
1.98 + };
1.99 + SkTDArray<Segment> fSegments;
1.100 + SkTDArray<SkPoint> fPts; // Points used to define the segments
1.101 +
1.102 + static const Segment* NextSegment(const Segment*);
1.103 +
1.104 + void buildSegments();
1.105 + SkScalar compute_quad_segs(const SkPoint pts[3], SkScalar distance,
1.106 + int mint, int maxt, int ptIndex);
1.107 + SkScalar compute_cubic_segs(const SkPoint pts[3], SkScalar distance,
1.108 + int mint, int maxt, int ptIndex);
1.109 + const Segment* distanceToSegment(SkScalar distance, SkScalar* t);
1.110 +};
1.111 +
1.112 +#endif
