| /* |
| * Copyright (C) 2006 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef SkPathMeasure_DEFINED |
| #define SkPathMeasure_DEFINED |
| |
| #include "SkPath.h" |
| #include "SkTDArray.h" |
| |
| class SkPathMeasure : SkNoncopyable { |
| public: |
| SkPathMeasure(); |
| /** Initialize the pathmeasure with the specified path. The path must remain valid |
| for the lifetime of the measure object, or until setPath() is called with |
| a different path (or null), since the measure object keeps a pointer to the |
| path object (does not copy its data). |
| */ |
| SkPathMeasure(const SkPath& path, bool forceClosed); |
| ~SkPathMeasure(); |
| |
| /** Reset the pathmeasure with the specified path. The path must remain valid |
| for the lifetime of the measure object, or until setPath() is called with |
| a different path (or null), since the measure object keeps a pointer to the |
| path object (does not copy its data). |
| */ |
| void setPath(const SkPath*, bool forceClosed); |
| |
| /** Return the total length of the current contour, or 0 if no path |
| is associated (e.g. resetPath(null)) |
| */ |
| SkScalar getLength(); |
| |
| /** Pins distance to 0 <= distance <= getLength(), and then computes |
| the corresponding position and tangent. |
| Returns false if there is no path, or a zero-length path was specified, in which case |
| position and tangent are unchanged. |
| */ |
| bool getPosTan(SkScalar distance, SkPoint* position, SkVector* tangent); |
| |
| enum MatrixFlags { |
| kGetPosition_MatrixFlag = 0x01, |
| kGetTangent_MatrixFlag = 0x02, |
| kGetPosAndTan_MatrixFlag = kGetPosition_MatrixFlag | kGetTangent_MatrixFlag |
| }; |
| /** Pins distance to 0 <= distance <= getLength(), and then computes |
| the corresponding matrix (by calling getPosTan). |
| Returns false if there is no path, or a zero-length path was specified, in which case |
| matrix is unchanged. |
| */ |
| bool getMatrix(SkScalar distance, SkMatrix* matrix, MatrixFlags flags = kGetPosAndTan_MatrixFlag); |
| /** Given a start and stop distance, return in dst the intervening segment(s). |
| If the segment is zero-length, return false, else return true. |
| startD and stopD are pinned to legal values (0..getLength()). If startD <= stopD |
| then return false (and leave dst untouched). |
| Begin the segment with a moveTo if startWithMoveTo is true |
| */ |
| bool getSegment(SkScalar startD, SkScalar stopD, SkPath* dst, bool startWithMoveTo); |
| |
| /** Return true if the current contour is closed() |
| */ |
| bool isClosed(); |
| |
| /** Move to the next contour in the path. Return true if one exists, or false if |
| we're done with the path. |
| */ |
| bool nextContour(); |
| |
| #ifdef SK_DEBUG |
| void dump(); |
| static void UnitTest(); |
| #endif |
| |
| private: |
| SkPath::Iter fIter; |
| const SkPath* fPath; |
| SkScalar fLength; // relative to the current contour |
| int fFirstPtIndex; // relative to the current contour |
| bool fIsClosed; // relative to the current contour |
| bool fForceClosed; |
| |
| struct Segment { |
| SkScalar fDistance; // total distance up to this point |
| unsigned fPtIndex : 15; |
| unsigned fTValue : 15; |
| unsigned fType : 2; |
| |
| SkScalar getScalarT() const; |
| }; |
| SkTDArray<Segment> fSegments; |
| |
| static const Segment* NextSegment(const Segment*); |
| |
| void buildSegments(); |
| SkScalar compute_quad_segs(const SkPoint pts[3], SkScalar distance, |
| int mint, int maxt, int ptIndex); |
| SkScalar compute_cubic_segs(const SkPoint pts[3], SkScalar distance, |
| int mint, int maxt, int ptIndex); |
| const Segment* distanceToSegment(SkScalar distance, SkScalar* t); |
| }; |
| |
| #endif |
| |