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-rw-r--r--src/SDL_gfxBlitFunc.h128
1 files changed, 128 insertions, 0 deletions
diff --git a/src/SDL_gfxBlitFunc.h b/src/SDL_gfxBlitFunc.h
new file mode 100644
index 000000000..f233aa617
--- /dev/null
+++ b/src/SDL_gfxBlitFunc.h
@@ -0,0 +1,128 @@
+/*
+
+ 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>
+
+/* -------- Prototypes */
+
+#ifdef WIN32
+# ifdef DLL_EXPORT
+# 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);
+
+
+/* -------- Macros */
+
+/* Define SDL macros locally as a substitute for a #include "SDL_blit.h", */
+
+/* which doesn't work since the include file doesn't get installed. */
+
+/* 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;
+
+#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; \
+}
+
+#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)
+
+#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); \
+}
+
+#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; \
+}
+
+/* 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)
+
+/* This is a very useful loop for optimizing blitters */
+
+/* 4-times unrolled loop */
+#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 ); \
+ } \
+}
+
+//deleted
+
+/* --- */
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _SDL_gfxBlitFunc_h */