aboutsummaryrefslogtreecommitdiffstats
path: root/libart_lgpl/art_render.h
blob: 0675722add9814c612a8e0362039162a58fce61c (plain) (blame)
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
/*
 * art_render.h: Modular rendering architecture.
 *
 * Libart_LGPL - library of basic graphic primitives
 * Copyright (C) 2000 Raph Levien
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifndef __ART_RENDER_H__
#define __ART_RENDER_H__

#include <libart_lgpl/art_alphagamma.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/* Render object */

#ifndef ART_MAX_DEPTH
#define ART_MAX_DEPTH 16
#endif

#if ART_MAX_DEPTH == 16
typedef art_u16 ArtPixMaxDepth;
#define ART_PIX_MAX_FROM_8(x) ((x) | ((x) << 8))
#define ART_PIX_8_FROM_MAX(x) (((x) + 0x80 - (((x) + 0x80) >> 8)) >> 8)
#else
#if ART_MAX_DEPTH == 8
typedef art_u8 ArtPixMaxDepth;
#define ART_PIX_MAX_FROM_8(x) (x)
#define ART_PIX_8_FROM_MAX(x) (x)
#else
#error ART_MAX_DEPTH must be either 8 or 16
#endif
#endif

#define ART_MAX_CHAN 16

typedef struct _ArtRender ArtRender;
typedef struct _ArtRenderCallback ArtRenderCallback;
typedef struct _ArtRenderMaskRun ArtRenderMaskRun;
typedef struct _ArtImageSource ArtImageSource;
typedef struct _ArtMaskSource ArtMaskSource;

typedef enum {
  ART_ALPHA_NONE      = 0,
  ART_ALPHA_SEPARATE  = 1,
  ART_ALPHA_PREMUL    = 2
} ArtAlphaType;

typedef enum {
  ART_COMPOSITE_NORMAL,
  ART_COMPOSITE_MULTIPLY,
  /* todo: more */
  ART_COMPOSITE_CUSTOM
} ArtCompositingMode;

typedef enum {
  ART_IMAGE_SOURCE_CAN_CLEAR = 1,
  ART_IMAGE_SOURCE_CAN_COMPOSITE = 2
} ArtImageSourceFlags;

struct _ArtRenderMaskRun {
  gint x;
  gint alpha;
};

struct _ArtRenderCallback {
  void (*render) (ArtRenderCallback *self, ArtRender *render,
          art_u8 *dest, gint y);
  void (*done) (ArtRenderCallback *self, ArtRender *render);
};

struct _ArtImageSource {
  ArtRenderCallback super;
  void (*negotiate) (ArtImageSource *self, ArtRender *render,
             ArtImageSourceFlags *p_flags,
             gint *p_buf_depth, ArtAlphaType *p_alpha_type);
};

struct _ArtMaskSource {
  ArtRenderCallback super;
  gint (*can_drive) (ArtMaskSource *self, ArtRender *render);
  /* For each mask source, ::prepare() is invoked if it is not
     a driver, or ::invoke_driver () if it is. */
  void (*invoke_driver) (ArtMaskSource *self, ArtRender *render);
  void (*prepare) (ArtMaskSource *self, ArtRender *render, art_boolean first);
};

struct _ArtRender {
  /* parameters of destination image */
  gint x0, y0;
  gint x1, y1;
  art_u8 *pixels;
  gint rowstride;
  gint n_chan;
  gint depth;
  ArtAlphaType alpha_type;

  art_boolean clear;
  ArtPixMaxDepth clear_color[ART_MAX_CHAN + 1];
  art_u32 opacity; /*[0..0x10000] */

  ArtCompositingMode compositing_mode;

  ArtAlphaGamma *alphagamma;

  art_u8 *alpha_buf;

  /* parameters of intermediate buffer */
  gint buf_depth;
  ArtAlphaType buf_alpha;
  art_u8 *image_buf;

  /* driving alpha scanline data */
  /* A "run" is a contiguous sequence of x values with the same alpha value. */
  gint n_run;
  ArtRenderMaskRun *run;

  /* A "span" is a contiguous sequence of x values with non-zero alpha. */
  gint n_span;
  gint *span_x;

  art_boolean need_span;
};

#ifdef __cplusplus
}
#endif /* __cplusplus */

#endif /* __ART_RENDER_H__ */