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#include "include/private/SkTo.h"
15
16struct GrIRect16 {
17 int16_t fLeft, fTop, fRight, fBottom;
18
19 static GrIRect16 SK_WARN_UNUSED_RESULT MakeEmpty() {
20 GrIRect16 r;
21 r.setEmpty();
22 return r;
23 }
24
25 static GrIRect16 SK_WARN_UNUSED_RESULT MakeWH(int16_t w, int16_t h) {
26 GrIRect16 r;
27 r.set(0, 0, w, h);
28 return r;
29 }
30
31 static GrIRect16 SK_WARN_UNUSED_RESULT MakeXYWH(int16_t x, int16_t y, int16_t w, int16_t h) {
32 GrIRect16 r;
33 r.set(x, y, x + w, y + h);
34 return r;
35 }
36
37 static GrIRect16 SK_WARN_UNUSED_RESULT Make(const SkIRect& ir) {
38 GrIRect16 r;
39 r.set(ir);
40 return r;
41 }
42
43 int width() const { return fRight - fLeft; }
44 int height() const { return fBottom - fTop; }
45 int area() const { return this->width() * this->height(); }
46 bool isEmpty() const { return fLeft >= fRight || fTop >= fBottom; }
47
48 void setEmpty() { memset(this, 0, sizeof(*this)); }
49
50 void set(int16_t left, int16_t top, int16_t right, int16_t bottom) {
51 fLeft = left;
52 fTop = top;
53 fRight = right;
54 fBottom = bottom;
55 }
56
57 void set(const SkIRect& r) {
58 fLeft = SkToS16(r.fLeft);
59 fTop = SkToS16(r.fTop);
60 fRight = SkToS16(r.fRight);
61 fBottom = SkToS16(r.fBottom);
62 }
63
64 void offset(int16_t dx, int16_t dy) {
65 fLeft += dx;
66 fTop += dy;
67 fRight += dx;
68 fBottom += dy;
69 }
70};
71
72/** Returns true if the rectangles have a nonzero area of overlap. It assumed that rects can be
73 infinitely small but not "inverted". */
74static inline bool GrRectsOverlap(const SkRect& a, const SkRect& b) {
75 // See skbug.com/6607 about the isFinite() checks.
76 SkASSERT(!a.isFinite() || (a.fLeft <= a.fRight && a.fTop <= a.fBottom));
77 SkASSERT(!b.isFinite() || (b.fLeft <= b.fRight && b.fTop <= b.fBottom));
78 return a.fRight > b.fLeft && a.fBottom > b.fTop && b.fRight > a.fLeft && b.fBottom > a.fTop;
79}
80
81/** Returns true if the rectangles overlap or share an edge or corner. It assumed that rects can be
82 infinitely small but not "inverted". */
83static inline bool GrRectsTouchOrOverlap(const SkRect& a, const SkRect& b) {
84 // See skbug.com/6607 about the isFinite() checks.
85 SkASSERT(!a.isFinite() || (a.fLeft <= a.fRight && a.fTop <= a.fBottom));
86 SkASSERT(!b.isFinite() || (b.fLeft <= b.fRight && b.fTop <= b.fBottom));
87 return a.fRight >= b.fLeft && a.fBottom >= b.fTop && b.fRight >= a.fLeft && b.fBottom >= a.fTop;
88}
89
90/**
91 * Apply the transform from 'inRect' to 'outRect' to each point in 'inPts', storing the mapped point
92 * into the parallel index of 'outPts'.
93 */
94static inline void GrMapRectPoints(const SkRect& inRect, const SkRect& outRect,
95 const SkPoint inPts[], SkPoint outPts[], int ptCount) {
96 SkMatrix rectTransform = SkMatrix::MakeRectToRect(inRect, outRect, SkMatrix::kFill_ScaleToFit);
97 rectTransform.mapPoints(outPts, inPts, ptCount);
98}
99
100/**
101 * Clips the srcRect and the dstPoint to the bounds of the srcSize and dstSize respectively. Returns
102 * true if the srcRect and dstRect intersect the srcRect and dst rect (dstPoint with srcRect
103 * width/height). Returns false otherwise. The clipped values are returned in clippedSrcRect and
104 * clippedDstPoint.
105 */
106static inline bool GrClipSrcRectAndDstPoint(const SkISize& dstSize,
107 const SkISize& srcSize,
108 const SkIRect& srcRect,
109 const SkIPoint& dstPoint,
110 SkIRect* clippedSrcRect,
111 SkIPoint* clippedDstPoint) {
112 *clippedSrcRect = srcRect;
113 *clippedDstPoint = dstPoint;
114
115 // clip the left edge to src and dst bounds, adjusting dstPoint if necessary
116 if (clippedSrcRect->fLeft < 0) {
117 clippedDstPoint->fX -= clippedSrcRect->fLeft;
118 clippedSrcRect->fLeft = 0;
119 }
120 if (clippedDstPoint->fX < 0) {
121 clippedSrcRect->fLeft -= clippedDstPoint->fX;
122 clippedDstPoint->fX = 0;
123 }
124
125 // clip the top edge to src and dst bounds, adjusting dstPoint if necessary
126 if (clippedSrcRect->fTop < 0) {
127 clippedDstPoint->fY -= clippedSrcRect->fTop;
128 clippedSrcRect->fTop = 0;
129 }
130 if (clippedDstPoint->fY < 0) {
131 clippedSrcRect->fTop -= clippedDstPoint->fY;
132 clippedDstPoint->fY = 0;
133 }
134
135 // clip the right edge to the src and dst bounds.
136 if (clippedSrcRect->fRight > srcSize.width()) {
137 clippedSrcRect->fRight = srcSize.width();
138 }
139 if (clippedDstPoint->fX + clippedSrcRect->width() > dstSize.width()) {
140 clippedSrcRect->fRight = clippedSrcRect->fLeft + dstSize.width() - clippedDstPoint->fX;
141 }
142
143 // clip the bottom edge to the src and dst bounds.
144 if (clippedSrcRect->fBottom > srcSize.height()) {
145 clippedSrcRect->fBottom = srcSize.height();
146 }
147 if (clippedDstPoint->fY + clippedSrcRect->height() > dstSize.height()) {
148 clippedSrcRect->fBottom = clippedSrcRect->fTop + dstSize.height() - clippedDstPoint->fY;
149 }
150
151 // The above clipping steps may have inverted the rect if it didn't intersect either the src or
152 // dst bounds.
153 return !clippedSrcRect->isEmpty();
154}
155#endif
156