1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/include/core/SkLineClipper.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,47 @@
1.4 +
1.5 +/*
1.6 + * Copyright 2011 Google Inc.
1.7 + *
1.8 + * Use of this source code is governed by a BSD-style license that can be
1.9 + * found in the LICENSE file.
1.10 + */
1.11 +#ifndef SkLineClipper_DEFINED
1.12 +#define SkLineClipper_DEFINED
1.13 +
1.14 +#include "SkRect.h"
1.15 +#include "SkPoint.h"
1.16 +
1.17 +class SkLineClipper {
1.18 +public:
1.19 + enum {
1.20 + kMaxPoints = 4,
1.21 + kMaxClippedLineSegments = kMaxPoints - 1
1.22 + };
1.23 +
1.24 + /* Clip the line pts[0]...pts[1] against clip, ignoring segments that
1.25 + lie completely above or below the clip. For portions to the left or
1.26 + right, turn those into vertical line segments that are aligned to the
1.27 + edge of the clip.
1.28 +
1.29 + Return the number of line segments that result, and store the end-points
1.30 + of those segments sequentially in lines as follows:
1.31 + 1st segment: lines[0]..lines[1]
1.32 + 2nd segment: lines[1]..lines[2]
1.33 + 3rd segment: lines[2]..lines[3]
1.34 + */
1.35 + static int ClipLine(const SkPoint pts[2], const SkRect& clip,
1.36 + SkPoint lines[kMaxPoints]);
1.37 +
1.38 + /* Intersect the line segment against the rect. If there is a non-empty
1.39 + resulting segment, return true and set dst[] to that segment. If not,
1.40 + return false and ignore dst[].
1.41 +
1.42 + ClipLine is specialized for scan-conversion, as it adds vertical
1.43 + segments on the sides to show where the line extended beyond the
1.44 + left or right sides. IntersectLine does not.
1.45 + */
1.46 + static bool IntersectLine(const SkPoint src[2], const SkRect& clip,
1.47 + SkPoint dst[2]);
1.48 +};
1.49 +
1.50 +#endif
