1 /*
2 * Copyright 2011 The Android Open Source Project
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
9 #ifndef SkScan_DEFINED
10 #define SkScan_DEFINED
11
12 #include "include/core/SkPoint.h"
13 #include "include/core/SkRect.h"
14 #include "include/private/base/SkFixed.h"
15
16 class SkBlitter;
17 class SkPath;
18 class SkRasterClip;
19 class SkRegion;
20
21 /** Defines a fixed-point rectangle, identical to the integer SkIRect, but its
22 coordinates are treated as SkFixed rather than int32_t.
23 */
24 typedef SkIRect SkXRect;
25
26 class SkScan {
27 public:
28 /*
29 * Draws count-1 line segments, one at a time:
30 * line(pts[0], pts[1])
31 * line(pts[1], pts[2])
32 * line(......, pts[count - 1])
33 */
34 typedef void (*HairRgnProc)(const SkPoint[], int count, const SkRegion*, SkBlitter*);
35 typedef void (*HairRCProc)(const SkPoint[], int count, const SkRasterClip&, SkBlitter*);
36
37 static void FillPath(const SkPath&, const SkIRect&, SkBlitter*);
38
39 // Paths of a certain size cannot be anti-aliased unless externally tiled (handled by SkDraw).
40 // SkBitmapDevice automatically tiles, SkAAClip does not so SkRasterClipStack converts AA clips
41 // to BW clips if that's the case. SkRegion uses this to know when to tile and union smaller
42 // SkRegions together.
43 static bool PathRequiresTiling(const SkIRect& bounds);
44
45 ///////////////////////////////////////////////////////////////////////////
46 // rasterclip
47
48 static void FillIRect(const SkIRect&, const SkRasterClip&, SkBlitter*);
49 static void FillXRect(const SkXRect&, const SkRasterClip&, SkBlitter*);
50 static void FillRect(const SkRect&, const SkRasterClip&, SkBlitter*);
51 static void AntiFillRect(const SkRect&, const SkRasterClip&, SkBlitter*);
52 static void AntiFillXRect(const SkXRect&, const SkRasterClip&, SkBlitter*);
53 static void FillPath(const SkPath&, const SkRasterClip&, SkBlitter*);
54 static void AntiFillPath(const SkPath&, const SkRasterClip&, SkBlitter*);
55 static void FrameRect(const SkRect&, const SkPoint& strokeSize,
56 const SkRasterClip&, SkBlitter*);
57 static void AntiFrameRect(const SkRect&, const SkPoint& strokeSize,
58 const SkRasterClip&, SkBlitter*);
59 static void FillTriangle(const SkPoint pts[], const SkRasterClip&, SkBlitter*);
60 static void HairLine(const SkPoint[], int count, const SkRasterClip&, SkBlitter*);
61 static void AntiHairLine(const SkPoint[], int count, const SkRasterClip&, SkBlitter*);
62 static void HairRect(const SkRect&, const SkRasterClip&, SkBlitter*);
63 static void AntiHairRect(const SkRect&, const SkRasterClip&, SkBlitter*);
64 static void HairPath(const SkPath&, const SkRasterClip&, SkBlitter*);
65 static void AntiHairPath(const SkPath&, const SkRasterClip&, SkBlitter*);
66 static void HairSquarePath(const SkPath&, const SkRasterClip&, SkBlitter*);
67 static void AntiHairSquarePath(const SkPath&, const SkRasterClip&, SkBlitter*);
68 static void HairRoundPath(const SkPath&, const SkRasterClip&, SkBlitter*);
69 static void AntiHairRoundPath(const SkPath&, const SkRasterClip&, SkBlitter*);
70
71 // Needed by SkRegion::setPath
72 static void FillPath(const SkPath&, const SkRegion& clip, SkBlitter*);
73
74 private:
75 friend class SkAAClip;
76 friend class SkRegion;
77
78 static void FillIRect(const SkIRect&, const SkRegion* clip, SkBlitter*);
79 static void FillXRect(const SkXRect&, const SkRegion* clip, SkBlitter*);
80 static void FillRect(const SkRect&, const SkRegion* clip, SkBlitter*);
81 static void AntiFillRect(const SkRect&, const SkRegion* clip, SkBlitter*);
82 static void AntiFillXRect(const SkXRect&, const SkRegion*, SkBlitter*);
83 static void AntiFillPath(const SkPath&, const SkRegion& clip, SkBlitter*, bool forceRLE);
84 static void FillTriangle(const SkPoint pts[], const SkRegion*, SkBlitter*);
85
86 static void AntiFrameRect(const SkRect&, const SkPoint& strokeSize,
87 const SkRegion*, SkBlitter*);
88 static void HairLineRgn(const SkPoint[], int count, const SkRegion*, SkBlitter*);
89 static void AntiHairLineRgn(const SkPoint[], int count, const SkRegion*, SkBlitter*);
90 static void AAAFillPath(const SkPath& path, SkBlitter* blitter, const SkIRect& pathIR,
91 const SkIRect& clipBounds, bool forceRLE);
92 };
93
94 /** Assign an SkXRect from a SkIRect, by promoting the src rect's coordinates
95 from int to SkFixed. Does not check for overflow if the src coordinates
96 exceed 32K
97 */
XRect_set(SkXRect * xr,const SkIRect & src)98 static inline void XRect_set(SkXRect* xr, const SkIRect& src) {
99 xr->fLeft = SkIntToFixed(src.fLeft);
100 xr->fTop = SkIntToFixed(src.fTop);
101 xr->fRight = SkIntToFixed(src.fRight);
102 xr->fBottom = SkIntToFixed(src.fBottom);
103 }
104
105 /** Assign an SkXRect from a SkRect, by promoting the src rect's coordinates
106 from SkScalar to SkFixed. Does not check for overflow if the src coordinates
107 exceed 32K
108 */
XRect_set(SkXRect * xr,const SkRect & src)109 static inline void XRect_set(SkXRect* xr, const SkRect& src) {
110 xr->fLeft = SkScalarToFixed(src.fLeft);
111 xr->fTop = SkScalarToFixed(src.fTop);
112 xr->fRight = SkScalarToFixed(src.fRight);
113 xr->fBottom = SkScalarToFixed(src.fBottom);
114 }
115
116 /** Round the SkXRect coordinates, and store the result in the SkIRect.
117 */
XRect_round(const SkXRect & xr,SkIRect * dst)118 static inline void XRect_round(const SkXRect& xr, SkIRect* dst) {
119 dst->fLeft = SkFixedRoundToInt(xr.fLeft);
120 dst->fTop = SkFixedRoundToInt(xr.fTop);
121 dst->fRight = SkFixedRoundToInt(xr.fRight);
122 dst->fBottom = SkFixedRoundToInt(xr.fBottom);
123 }
124
125 /** Round the SkXRect coordinates out (i.e. use floor for left/top, and ceiling
126 for right/bottom), and store the result in the SkIRect.
127 */
XRect_roundOut(const SkXRect & xr,SkIRect * dst)128 static inline void XRect_roundOut(const SkXRect& xr, SkIRect* dst) {
129 dst->fLeft = SkFixedFloorToInt(xr.fLeft);
130 dst->fTop = SkFixedFloorToInt(xr.fTop);
131 dst->fRight = SkFixedCeilToInt(xr.fRight);
132 dst->fBottom = SkFixedCeilToInt(xr.fBottom);
133 }
134
135 #endif
136