e16efc1882
git-svn-id: http://skia.googlecode.com/svn/trunk@7406 2bbb7eff-a529-9590-31e7-b0007b416f81
48 lines
1.5 KiB
C++
48 lines
1.5 KiB
C++
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/*
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* Copyright 2011 Google Inc.
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#ifndef SkLineClipper_DEFINED
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#define SkLineClipper_DEFINED
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#include "SkRect.h"
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#include "SkPoint.h"
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class SkLineClipper {
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public:
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enum {
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kMaxPoints = 4,
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kMaxClippedLineSegments = kMaxPoints - 1
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};
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/* Clip the line pts[0]...pts[1] against clip, ignoring segments that
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lie completely above or below the clip. For portions to the left or
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right, turn those into vertical line segments that are aligned to the
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edge of the clip.
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Return the number of line segments that result, and store the end-points
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of those segments sequentially in lines as follows:
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1st segment: lines[0]..lines[1]
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2nd segment: lines[1]..lines[2]
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3rd segment: lines[2]..lines[3]
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*/
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static int ClipLine(const SkPoint pts[2], const SkRect& clip,
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SkPoint lines[kMaxPoints]);
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/* Intersect the line segment against the rect. If there is a non-empty
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resulting segment, return true and set dst[] to that segment. If not,
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return false and ignore dst[].
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ClipLine is specialized for scan-conversion, as it adds vertical
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segments on the sides to show where the line extended beyond the
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left or right sides. IntersectLine does not.
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*/
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static bool IntersectLine(const SkPoint src[2], const SkRect& clip,
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SkPoint dst[2]);
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};
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#endif
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