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