/*
* 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 {
int x;
int alpha;
};
struct _ArtRenderCallback {
void (*render) (ArtRenderCallback *self, ArtRender *render,
art_u8 *dest, int y);
void (*done) (ArtRenderCallback *self, ArtRender *render);
};
struct _ArtImageSource {
ArtRenderCallback super;
void (*negotiate) (ArtImageSource *self, ArtRender *render,
ArtImageSourceFlags *p_flags,
int *p_buf_depth, ArtAlphaType *p_alpha_type);
};
struct _ArtMaskSource {
ArtRenderCallback super;
int (*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 */
int x0, y0;
int x1, y1;
art_u8 *pixels;
int rowstride;
int n_chan;
int 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 */
int 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. */
int n_run;
ArtRenderMaskRun *run;
/* A "span" is a contiguous sequence of x values with non-zero alpha. */
int n_span;
int *span_x;
art_boolean need_span;
};
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __ART_RENDER_H__ */