1 /*
2 * Copyright 2010 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
8 #ifndef GrRect_DEFINED
9 #define GrRect_DEFINED
10
11 #include "include/core/SkMatrix.h"
12 #include "include/core/SkRect.h"
13 #include "include/core/SkTypes.h"
14
15 /** Returns true if the rectangles have a nonzero area of overlap. It assumed that rects can be
16 infinitely small but not "inverted". */
GrRectsOverlap(const SkRect & a,const SkRect & b)17 static inline bool GrRectsOverlap(const SkRect& a, const SkRect& b) {
18 // See skbug.com/6607 about the isFinite() checks.
19 SkASSERT(!a.isFinite() || (a.fLeft <= a.fRight && a.fTop <= a.fBottom));
20 SkASSERT(!b.isFinite() || (b.fLeft <= b.fRight && b.fTop <= b.fBottom));
21 return a.fRight > b.fLeft && a.fBottom > b.fTop && b.fRight > a.fLeft && b.fBottom > a.fTop;
22 }
23
24 /** Returns true if the rectangles overlap or share an edge or corner. It assumed that rects can be
25 infinitely small but not "inverted". */
GrRectsTouchOrOverlap(const SkRect & a,const SkRect & b)26 static inline bool GrRectsTouchOrOverlap(const SkRect& a, const SkRect& b) {
27 // See skbug.com/6607 about the isFinite() checks.
28 SkASSERT(!a.isFinite() || (a.fLeft <= a.fRight && a.fTop <= a.fBottom));
29 SkASSERT(!b.isFinite() || (b.fLeft <= b.fRight && b.fTop <= b.fBottom));
30 return a.fRight >= b.fLeft && a.fBottom >= b.fTop && b.fRight >= a.fLeft && b.fBottom >= a.fTop;
31 }
32
33 /**
34 * Apply the transform from 'inRect' to 'outRect' to each point in 'inPts', storing the mapped point
35 * into the parallel index of 'outPts'.
36 */
GrMapRectPoints(const SkRect & inRect,const SkRect & outRect,const SkPoint inPts[],SkPoint outPts[],int ptCount)37 static inline void GrMapRectPoints(const SkRect& inRect, const SkRect& outRect,
38 const SkPoint inPts[], SkPoint outPts[], int ptCount) {
39 SkMatrix::RectToRect(inRect, outRect).mapPoints(outPts, inPts, ptCount);
40 }
41
42 /**
43 * Clips the srcRect and the dstPoint to the bounds of the srcSize and dstSize respectively. Returns
44 * true if the srcRect and dstRect intersect the srcRect and dst rect (dstPoint with srcRect
45 * width/height). Returns false otherwise. The clipped values are stored back into 'dstPoint'
46 * and 'srcRect'
47 */
GrClipSrcRectAndDstPoint(const SkISize & dstSize,SkIPoint * dstPoint,const SkISize & srcSize,SkIRect * srcRect)48 static inline bool GrClipSrcRectAndDstPoint(const SkISize& dstSize,
49 SkIPoint* dstPoint,
50 const SkISize& srcSize,
51 SkIRect* srcRect) {
52 // clip the left edge to src and dst bounds, adjusting dstPoint if necessary
53 if (srcRect->fLeft < 0) {
54 dstPoint->fX -= srcRect->fLeft;
55 srcRect->fLeft = 0;
56 }
57 if (dstPoint->fX < 0) {
58 srcRect->fLeft -= dstPoint->fX;
59 dstPoint->fX = 0;
60 }
61
62 // clip the top edge to src and dst bounds, adjusting dstPoint if necessary
63 if (srcRect->fTop < 0) {
64 dstPoint->fY -= srcRect->fTop;
65 srcRect->fTop = 0;
66 }
67 if (dstPoint->fY < 0) {
68 srcRect->fTop -= dstPoint->fY;
69 dstPoint->fY = 0;
70 }
71
72 // clip the right edge to the src and dst bounds.
73 if (srcRect->fRight > srcSize.width()) {
74 srcRect->fRight = srcSize.width();
75 }
76 if (dstPoint->fX + srcRect->width() > dstSize.width()) {
77 srcRect->fRight = srcRect->fLeft + dstSize.width() - dstPoint->fX;
78 }
79
80 // clip the bottom edge to the src and dst bounds.
81 if (srcRect->fBottom > srcSize.height()) {
82 srcRect->fBottom = srcSize.height();
83 }
84 if (dstPoint->fY + srcRect->height() > dstSize.height()) {
85 srcRect->fBottom = srcRect->fTop + dstSize.height() - dstPoint->fY;
86 }
87
88 // The above clipping steps may have inverted the rect if it didn't intersect either the src or
89 // dst bounds.
90 return !srcRect->isEmpty();
91 }
92
93 #endif
94