1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*
*/
/** Antialiasing code **/
#include "sci/gfx/gfx_system.h"
#include "sci/gfx/gfx_tools.h"
namespace Sci {
static void antialiase_simple(gfx_pixmap_t *pixmap, int mask[], int shift_const, gfx_mode_t *mode) {
int x, y, c;
int bytespp = mode->bytespp;
int line_size = bytespp * pixmap->xl;
char *lastline[2];
char *lastline_p = NULL;
char *data_p = (char *)pixmap->data;
lastline[0] = (char *)sci_malloc(line_size);
lastline[1] = (char *)sci_malloc(line_size);
for (y = 0; y < pixmap->yl; y++) {
int visimode = (y > 0 && y + 1 < pixmap->yl) ? 1 : 0;
unsigned long last_pixel = 0;
memcpy(lastline[y & 1], data_p, line_size);
lastline_p = lastline[(y & 1)^1];
for (x = 0; x < pixmap->xl; x++) {
unsigned long result = 0;
if (x == 1)
visimode++;
else if (x + 1 == pixmap->xl)
visimode--;
for (c = 0; c < 3; c++) {
unsigned long accum = 0;
unsigned long reader = 0;
int y_mode;
/* Yes, bad compilers will read three times as often as neccessary.
** This optimization is straightforward to detect (common subexpression
** elemination), so I prefer to write the stuff semi-legibly...
*/
for (y_mode = 0; y_mode < 2; y_mode++)
if ((y_mode == 0 && y > 0)
|| (y_mode == 1 && y + 1 < pixmap->yl)) {
char *src = (y_mode) ? data_p + line_size : lastline_p;
if (x > 0) {
memcpy(&reader, src - bytespp, bytespp);
accum += ((reader >> shift_const) & mask[c]) << 0;
}
memcpy(&reader, src, bytespp);
accum += ((reader >> shift_const) & mask[c]) << 1;
if (x + 1 < pixmap->xl) {
memcpy(&reader, src + bytespp, bytespp);
accum += ((reader >> shift_const) & mask[c]) << 0;
}
}
if (x > 0)
accum += ((last_pixel >> shift_const) & mask[c]) << 1;
memcpy(&reader, data_p, bytespp);
if (c == 2)
last_pixel = reader;
accum += ((reader >> shift_const) & mask[c]) << 2;
if (x + 1 < pixmap->xl) {
memcpy(&reader, data_p + bytespp, bytespp);
accum += ((reader >> shift_const) & mask[c]) << 1;
}
switch (visimode) {
case 0:
accum /= 9; // Only happens twelve times
break;
case 1:
accum = (accum >> 6) + (accum >> 4); // 15/16 intensity
break;
case 2:
accum >>= 4;
break;
default:
accum = (c == 0) ? 0xffffffff : 0; // Error: mark as red
}
result |= (accum & mask[c]);
}
result <<= shift_const;
memcpy(data_p, &result, bytespp);
data_p += bytespp;
lastline_p += bytespp;
}
}
free(lastline[0]);
free(lastline[1]);
}
void gfxr_antialiase(gfx_pixmap_t *pixmap, gfx_mode_t *mode, gfxr_antialiasing_t type) {
int masks[3];
int shift_const = 0;
#ifdef SCUMM_BIG_ENDIAN
shift_const = (sizeof(unsigned long) - mode->bytespp) << 3;
#endif
masks[0] = mode->red_mask;
masks[1] = mode->green_mask;
masks[2] = mode->blue_mask;
if (mode->palette)
return;
switch (type) {
case GFXR_ANTIALIASING_NONE:
break;
case GFXR_ANTIALIASING_SIMPLE:
antialiase_simple(pixmap, masks, shift_const, mode);
break;
default:
GFXERROR("Invalid antialiasing mode %d (internal error)\n", type);
}
}
} // End of namespace Sci
|
