145 lines
3.5 KiB
C
145 lines
3.5 KiB
C
/*
|
|
|
|
SDL_gfxBlitFunc: custom blitters (part of SDL_gfx library)
|
|
|
|
LGPL (c) A. Schiffler
|
|
|
|
*/
|
|
|
|
#ifndef _SDL_gfxBlitFunc_h
|
|
#define _SDL_gfxBlitFunc_h
|
|
|
|
/* Set up for C function definitions, even when using C++ */
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
#include <SDL.h>
|
|
#include <SDL_video.h>
|
|
|
|
/* ---- Function Prototypes */
|
|
|
|
#if defined(WIN32) || defined(WIN64)
|
|
# if defined(DLL_EXPORT) && !defined(LIBSDL_GFX_DLL_IMPORT)
|
|
# define SDL_GFXBLITFUNC_SCOPE __declspec(dllexport)
|
|
# else
|
|
# ifdef LIBSDL_GFX_DLL_IMPORT
|
|
# define SDL_GFXBLITFUNC_SCOPE __declspec(dllimport)
|
|
# endif
|
|
# endif
|
|
#endif
|
|
#ifndef SDL_GFXBLITFUNC_SCOPE
|
|
# define SDL_GFXBLITFUNC_SCOPE extern
|
|
#endif
|
|
|
|
|
|
SDL_GFXBLITFUNC_SCOPE int SDL_gfxBlitRGBA(SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst, SDL_Rect * dstrect);
|
|
|
|
SDL_GFXBLITFUNC_SCOPE int SDL_gfxSetAlpha(SDL_Surface * src, Uint8 a);
|
|
|
|
SDL_GFXBLITFUNC_SCOPE int SDL_gfxMultiplyAlpha(SDL_Surface * src, Uint8 a);
|
|
|
|
/* -------- Macros */
|
|
|
|
/* Define SDL macros locally as a substitute for an #include "SDL_blit.h", */
|
|
/* which doesn't work since the include file doesn't get installed. */
|
|
|
|
/*!
|
|
\brief The structure passed to the low level blit functions.
|
|
*/
|
|
typedef struct {
|
|
Uint8 *s_pixels;
|
|
int s_width;
|
|
int s_height;
|
|
int s_skip;
|
|
Uint8 *d_pixels;
|
|
int d_width;
|
|
int d_height;
|
|
int d_skip;
|
|
void *aux_data;
|
|
SDL_PixelFormat *src;
|
|
Uint8 *table;
|
|
SDL_PixelFormat *dst;
|
|
} SDL_gfxBlitInfo;
|
|
|
|
/*!
|
|
\brief Unwrap RGBA values from a pixel using mask, shift and loss for surface.
|
|
*/
|
|
#define GFX_RGBA_FROM_PIXEL(pixel, fmt, r, g, b, a) \
|
|
{ \
|
|
r = ((pixel&fmt->Rmask)>>fmt->Rshift)<<fmt->Rloss; \
|
|
g = ((pixel&fmt->Gmask)>>fmt->Gshift)<<fmt->Gloss; \
|
|
b = ((pixel&fmt->Bmask)>>fmt->Bshift)<<fmt->Bloss; \
|
|
a = ((pixel&fmt->Amask)>>fmt->Ashift)<<fmt->Aloss; \
|
|
}
|
|
|
|
/*!
|
|
\brief Disassemble buffer pointer into a pixel and separate RGBA values.
|
|
*/
|
|
#define GFX_DISEMBLE_RGBA(buf, bpp, fmt, pixel, r, g, b, a) \
|
|
do { \
|
|
pixel = *((Uint32 *)(buf)); \
|
|
GFX_RGBA_FROM_PIXEL(pixel, fmt, r, g, b, a); \
|
|
pixel &= ~fmt->Amask; \
|
|
} while(0)
|
|
|
|
/*!
|
|
\brief Wrap a pixel from RGBA values using mask, shift and loss for surface.
|
|
*/
|
|
#define GFX_PIXEL_FROM_RGBA(pixel, fmt, r, g, b, a) \
|
|
{ \
|
|
pixel = ((r>>fmt->Rloss)<<fmt->Rshift)| \
|
|
((g>>fmt->Gloss)<<fmt->Gshift)| \
|
|
((b>>fmt->Bloss)<<fmt->Bshift)| \
|
|
((a<<fmt->Aloss)<<fmt->Ashift); \
|
|
}
|
|
|
|
/*!
|
|
\brief Assemble pixel into buffer pointer from separate RGBA values.
|
|
*/
|
|
#define GFX_ASSEMBLE_RGBA(buf, bpp, fmt, r, g, b, a) \
|
|
{ \
|
|
Uint32 pixel; \
|
|
\
|
|
GFX_PIXEL_FROM_RGBA(pixel, fmt, r, g, b, a); \
|
|
*((Uint32 *)(buf)) = pixel; \
|
|
}
|
|
|
|
/*!
|
|
\brief Blend the RGB values of two pixels based on a source alpha value.
|
|
*/
|
|
#define GFX_ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB) \
|
|
do { \
|
|
dR = (((sR-dR)*(A))/255)+dR; \
|
|
dG = (((sG-dG)*(A))/255)+dG; \
|
|
dB = (((sB-dB)*(A))/255)+dB; \
|
|
} while(0)
|
|
|
|
/*!
|
|
\brief 4-times unrolled DUFFs loop.
|
|
|
|
This is a very useful loop for optimizing blitters.
|
|
*/
|
|
#define GFX_DUFFS_LOOP4(pixel_copy_increment, width) \
|
|
{ int n = (width+3)/4; \
|
|
switch (width & 3) { \
|
|
case 0: do { pixel_copy_increment; \
|
|
case 3: pixel_copy_increment; \
|
|
case 2: pixel_copy_increment; \
|
|
case 1: pixel_copy_increment; \
|
|
} while ( --n > 0 ); \
|
|
} \
|
|
}
|
|
|
|
|
|
|
|
/* Ends C function definitions when using C++ */
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* _SDL_gfxBlitFunc_h */
|