SkPathOps.h revision 7839ce1af63bf12fe7b3caa866970bbbb3afb13d 
1/*
2 * Copyright 2012 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7#ifndef SkPathOps_DEFINED
8#define SkPathOps_DEFINED
9
10class SkPath;
11
12// FIXME: move everything below into the SkPath class
13/**
14  *  The logical operations that can be performed when combining two paths.
15  */
16enum SkPathOp {
17    kDifference_PathOp,         //!< subtract the op path from the first path
18    kIntersect_PathOp,          //!< intersect the two paths
19    kUnion_PathOp,              //!< union (inclusive-or) the two paths
20    kXOR_PathOp,                //!< exclusive-or the two paths
21    kReverseDifference_PathOp,  //!< subtract the first path from the op path
22};
23
24/** Set this path to the result of applying the Op to this path and the
25    specified path: this = (this op operand).
26    The resulting path will be constructed from non-overlapping contours.
27    The curve order is reduced where possible so that cubics may be turned
28    into quadratics, and quadratics maybe turned into lines.
29
30    Returns true if operation was able to produce a result;
31    otherwise, result is unmodified.
32
33    @param one The first operand (for difference, the minuend)
34    @param two The second operand (for difference, the subtrahend)
35    @param result The product of the operands. The result may be one of the
36                  inputs.
37    @return True if operation succeeded.
38  */
39bool Op(const SkPath& one, const SkPath& two, SkPathOp op, SkPath* result);
40
41/** Set this path to a set of non-overlapping contours that describe the
42    same area as the original path.
43    The curve order is reduced where possible so that cubics may
44    be turned into quadratics, and quadratics maybe turned into lines.
45
46    Returns true if operation was able to produce a result;
47    otherwise, result is unmodified.
48
49    @param path The path to simplify.
50    @param result The simplified path. The result may be the input.
51    @return True if simplification succeeded.
52  */
53bool Simplify(const SkPath& path, SkPath* result);
54
55#endif
56