56 lines
1.8 KiB
C
56 lines
1.8 KiB
C
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/*
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* Copyright (C) 2006 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef SkPerspIter_DEFINED
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#define SkPerspIter_DEFINED
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#include "SkMatrix.h"
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class SkPerspIter {
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public:
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/** Iterate a line through the matrix [x,y] ... [x+count-1, y].
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@param m The matrix we will be iterating a line through
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@param x The initial X coordinate to be mapped through the matrix
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@param y The initial Y coordinate to be mapped through the matrix
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@param count The number of points (x,y) (x+1,y) (x+2,y) ... we will eventually map
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*/
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SkPerspIter(const SkMatrix& m, SkScalar x, SkScalar y, int count);
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/** Return the buffer of [x,y] fixed point values we will be filling.
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This always returns the same value, so it can be saved across calls to
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next().
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*/
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const SkFixed* getXY() const { return fStorage; }
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/** Return the number of [x,y] pairs that have been filled in the getXY() buffer.
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When this returns 0, the iterator is finished.
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*/
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int next();
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private:
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enum {
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kShift = 4,
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kCount = (1 << kShift)
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};
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const SkMatrix& fMatrix;
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SkFixed fStorage[kCount * 2];
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SkFixed fX, fY;
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SkScalar fSX, fSY;
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int fCount;
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};
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#endif
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