1 /*
2 * Copyright 2006 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 #include "SkBitmap.h"
10 #include "SkMask.h"
11
12 #ifndef ClearLow3Bits_DEFINED
13 #define ClearLow3Bits_DEFINED
14 #define ClearLow3Bits(x) ((unsigned)(x) >> 3 << 3)
15 #endif
16
17 /*
18 SK_BLITBWMASK_NAME name of function(const SkBitmap& bitmap, const SkMask& mask, const SkIRect& clip, SK_BLITBWMASK_ARGS)
19 SK_BLITBWMASK_ARGS list of additional arguments to SK_BLITBWMASK_NAME, beginning with a comma
20 SK_BLITBWMASK_BLIT8 name of function(U8CPU byteMask, SK_BLITBWMASK_DEVTYPE* dst, int x, int y)
21 SK_BLITBWMASK_GETADDR either writable_addr[8,16,32]
22 SK_BLITBWMASK_DEVTYPE either U32 or U16 or U8
23 */
24
SK_BLITBWMASK_NAME(const SkPixmap & dst,const SkMask & srcMask,const SkIRect & clip SK_BLITBWMASK_ARGS)25 static void SK_BLITBWMASK_NAME(const SkPixmap& dst, const SkMask& srcMask,
26 const SkIRect& clip SK_BLITBWMASK_ARGS) {
27 SkASSERT(clip.fRight <= srcMask.fBounds.fRight);
28
29 int cx = clip.fLeft;
30 int cy = clip.fTop;
31 int maskLeft = srcMask.fBounds.fLeft;
32 unsigned mask_rowBytes = srcMask.fRowBytes;
33 size_t bitmap_rowBytes = dst.rowBytes();
34 unsigned height = clip.height();
35
36 SkASSERT(mask_rowBytes != 0);
37 SkASSERT(bitmap_rowBytes != 0);
38 SkASSERT(height != 0);
39
40 const uint8_t* bits = srcMask.getAddr1(cx, cy);
41 SK_BLITBWMASK_DEVTYPE* device = dst.SK_BLITBWMASK_GETADDR(cx, cy);
42
43 if (cx == maskLeft && clip.fRight == srcMask.fBounds.fRight)
44 {
45 do {
46 SK_BLITBWMASK_DEVTYPE* dst = device;
47 unsigned rb = mask_rowBytes;
48 do {
49 U8CPU mask = *bits++;
50 SK_BLITBWMASK_BLIT8(mask, dst);
51 dst += 8;
52 } while (--rb != 0);
53 device = (SK_BLITBWMASK_DEVTYPE*)((char*)device + bitmap_rowBytes);
54 } while (--height != 0);
55 }
56 else
57 {
58 int left_edge = cx - maskLeft;
59 SkASSERT(left_edge >= 0);
60 int rite_edge = clip.fRight - maskLeft;
61 SkASSERT(rite_edge > left_edge);
62
63 int left_mask = 0xFF >> (left_edge & 7);
64 int rite_mask = 0xFF << (8 - (rite_edge & 7));
65 rite_mask &= 0xFF; // only want low-8 bits of mask
66 int full_runs = (rite_edge >> 3) - ((left_edge + 7) >> 3);
67
68 // check for empty right mask, so we don't read off the end (or go slower than we need to)
69 if (rite_mask == 0)
70 {
71 SkASSERT(full_runs >= 0);
72 full_runs -= 1;
73 rite_mask = 0xFF;
74 }
75 if (left_mask == 0xFF)
76 full_runs -= 1;
77
78 // back up manually so we can keep in sync with our byte-aligned src
79 // and not trigger an assert from the getAddr## function
80 device -= left_edge & 7;
81
82 if (full_runs < 0)
83 {
84 left_mask &= rite_mask;
85 SkASSERT(left_mask != 0);
86 do {
87 U8CPU mask = *bits & left_mask;
88 SK_BLITBWMASK_BLIT8(mask, device);
89 bits += mask_rowBytes;
90 device = (SK_BLITBWMASK_DEVTYPE*)((char*)device + bitmap_rowBytes);
91 } while (--height != 0);
92 }
93 else
94 {
95 do {
96 int runs = full_runs;
97 SK_BLITBWMASK_DEVTYPE* dst = device;
98 const uint8_t* b = bits;
99 U8CPU mask;
100
101 mask = *b++ & left_mask;
102 SK_BLITBWMASK_BLIT8(mask, dst);
103 dst += 8;
104
105 while (--runs >= 0)
106 {
107 mask = *b++;
108 SK_BLITBWMASK_BLIT8(mask, dst);
109 dst += 8;
110 }
111
112 mask = *b & rite_mask;
113 SK_BLITBWMASK_BLIT8(mask, dst);
114
115 bits += mask_rowBytes;
116 device = (SK_BLITBWMASK_DEVTYPE*)((char*)device + bitmap_rowBytes);
117 } while (--height != 0);
118 }
119 }
120 }
121
122 #undef SK_BLITBWMASK_NAME
123 #undef SK_BLITBWMASK_ARGS
124 #undef SK_BLITBWMASK_BLIT8
125 #undef SK_BLITBWMASK_GETADDR
126 #undef SK_BLITBWMASK_DEVTYPE
127 #undef SK_BLITBWMASK_DOROWSETUP
128