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J. Duke319a3b92007-12-01 00:00:00 +00001/*
2 * Copyright 1996 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26/*
27 * This file contains macro definitions for the Encoding category of
28 * the macros used by the generic scaleloop function.
29 *
30 * This implementation uses an ordered dithering error matrix to
31 * produce a moderately high quality version of an image with only
32 * an 8-bit (or less) RGB colormap or an 8-bit grayramp. The ordered
33 * dithering technique does not rely on the order in which the pixels
34 * are processed so this file can be used in cases where the ImageProducer
35 * has not specified the TopDownLeftRight delivery hint. The ordered
36 * dither technique is also much faster than the Floyd-Steinberg error
37 * diffusion algorithm so this implementation would also be appropriate
38 * for cases where performance is critical such as the processing of a
39 * video stream.
40 *
41 * This file can be used to provide the default implementation of the
42 * Encoding macros for RGB colormapped or grayscale displays.
43 */
44
45/*
46 * These definitions vector the standard macro names to the "Any"
47 * versions of those macros. The "DitherDeclared" keyword is also
48 * defined to indicate to the other include files that they are not
49 * defining the primary implementation. All other include files
50 * will check for the existance of the "DitherDeclared" keyword
51 * and define their implementations of the Encoding macros using
52 * more specific names without overriding the standard names. This
53 * is done so that the other files can be included later to reuse
54 * their implementations for the specific cases.
55 */
56#define DitherDeclared
57#define DeclareDitherVars DeclareAnyDitherVars
58#define InitDither InitAnyDither
59#define StartDitherLine StartAnyDitherLine
60#define DitherPixel AnyDitherPixel
61#define DitherBufComplete AnyDitherBufComplete
62
63/*
64 * Include the specific implementation for grayscale displays.
65 * The implementor will have to include one of the color display
66 * implementations (img_ordclrsgn.h or img_ordclruns.h) manually.
67 */
68#include "img_ordgray.h"
69
70#define DeclareAnyDitherVars \
71 int grayscale; \
72 DeclareColorDitherVars \
73 DeclareGrayDitherVars \
74 int relx, rely;
75
76#define InitAnyDither(cvdata, clrdata, dstTW) \
77 do { \
78 if (grayscale = clrdata->grayscale) { \
79 InitGrayDither(cvdata, clrdata, dstTW); \
80 } else { \
81 InitColorDither(cvdata, clrdata, dstTW); \
82 } \
83 } while (0)
84
85#define StartAnyDitherLine(cvdata, dstX1, dstY) \
86 do { \
87 if (grayscale) { \
88 StartGrayDitherLine(cvdata, dstX1, dstY); \
89 } else { \
90 StartColorDitherLine(cvdata, dstX1, dstY); \
91 } \
92 } while (0)
93
94#define AnyDitherPixel(dstX, dstY, pixel, red, green, blue) \
95 do { \
96 if (grayscale) { \
97 GrayDitherPixel(dstX, dstY, pixel, red, green, blue); \
98 } else { \
99 ColorDitherPixel(dstX, dstY, pixel, red, green, blue); \
100 } \
101 } while (0)
102
103#define AnyDitherBufComplete(cvdata, dstX1) \
104 do { \
105 if (grayscale) { \
106 GrayDitherBufComplete(cvdata, dstX1); \
107 } else { \
108 ColorDitherBufComplete(cvdata, dstX1); \
109 } \
110 } while (0)