sdl_atarigl.c

SDL库 在进行视频显示程序spcaview安装时必须的库文件

			/* 15 bits unsupported */
			if (tinygl_present) {
				gl_pixelsize = 3;
				osmesa_format = VDI_RGB;
				if (redmask == 31<<10) {
					gl_copyshadow = CopyShadowRGBTo555;
				} else {
					gl_copyshadow = CopyShadowRGBTo565;
					gl_convert = Convert565To555le;
				}
			} else {
				gl_pixelsize = 4;
				gl_upsidedown = SDL_TRUE;
				osmesa_format = OSMESA_ARGB;
				if (redmask == 31<<10) {
					gl_copyshadow = CopyShadow8888To555;
				} else {
					gl_copyshadow = CopyShadow8888To565;
					gl_convert = Convert565To555le;
				}
			}
			break;
		case 16:
			/* 16 bits unsupported */
			if (tinygl_present) {
				gl_pixelsize = 3;
				osmesa_format = VDI_RGB;
				gl_copyshadow = CopyShadowRGBTo565;
				if (redmask != 31<<11) {
					/* 565, little endian, unsupported */
					gl_convert = Convert565le;
				}
			} else {
				gl_pixelsize = 4;
				gl_upsidedown = SDL_TRUE;
				osmesa_format = OSMESA_ARGB;
				gl_copyshadow = CopyShadow8888To565;
				if (redmask != 31<<11) {
					/* 565, little endian, unsupported */
					gl_convert = Convert565le;
				}
			}
			break;
		case 24:
			gl_pixelsize = 3;
			if (tinygl_present) {
				osmesa_format = VDI_RGB;
				gl_copyshadow = CopyShadowDirect;
				if (redmask != 255<<16) {
					gl_copyshadow = CopyShadowRGBSwap;
				}
			} else {
				gl_copyshadow = CopyShadowDirect;
				gl_upsidedown = SDL_TRUE;
				if (redmask == 255<<16) {
					osmesa_format = OSMESA_RGB;
				} else {
					osmesa_format = OSMESA_BGR;
				}
			}
			break;
		case 32:
			if (tinygl_present) {
				gl_pixelsize = 3;
				osmesa_format = VDI_RGB;
				gl_copyshadow = CopyShadowRGBToARGB;
				if (redmask == 255) {
					gl_convert = CopyShadowRGBToABGR;
				} else if (redmask == 255<<8) {
					gl_convert = CopyShadowRGBToBGRA;
				} else if (redmask == 255<<24) {
					gl_convert = CopyShadowRGBToRGBA;
				}
			} else {
				gl_pixelsize = 4;
				gl_upsidedown = SDL_TRUE;
				gl_copyshadow = CopyShadowDirect;
				if (redmask == 255<<16) {
					osmesa_format = OSMESA_ARGB;
				} else if (redmask == 255<<8) {
					osmesa_format = OSMESA_BGRA;
				} else if (redmask == 255<<24) {
					osmesa_format = OSMESA_RGBA;
				} else {
					/* ABGR format unsupported */
					osmesa_format = OSMESA_BGRA;
					gl_convert = ConvertBGRAToABGR;
				}
			}
			break;
		default:
			if (tinygl_present) {
				SDL_AtariGL_Quit(this, SDL_FALSE);
				return 0;
			}
			gl_pixelsize = 1;
			gl_copyshadow = CopyShadowDirect;
			osmesa_format = OSMESA_COLOR_INDEX;
			break;
	}

	/* Try to keep current context if possible */
	recreatecontext=1;
	if (gl_shadow &&
		(gl_curformat == osmesa_format) &&
		(gl_curwidth == current->w) &&
		(gl_curheight == current->h)) {
		recreatecontext = 0;
	}
	if (recreatecontext) {
		SDL_AtariGL_Quit(this, SDL_FALSE);

		gl_shadow = this->gl_data->OSMesaCreateLDG(
			osmesa_format, GL_UNSIGNED_BYTE, current->w, current->h
		);

		if (gl_shadow) {
			gl_curformat = osmesa_format;
			gl_curwidth = current->w;
			gl_curheight = current->h;
		} else {
			gl_curformat = 0;
			gl_curwidth = 0;
			gl_curheight = 0;
		}
	}

	return (gl_shadow != NULL);
}

/*--- Conversions routines from shadow buffer to the screen ---*/

static void CopyShadowNull(_THIS, SDL_Surface *surface)
{
}

static void CopyShadowDirect(_THIS, SDL_Surface *surface)
{
	int y, srcpitch, dstpitch;
	Uint8 *srcline, *dstline;

	srcline = gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		SDL_memcpy(dstline, srcline, srcpitch);

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBTo555(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint16 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>1;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;
		for (x=0; x<surface->w; x++) {
			Uint16 dstcolor;
			
			dstcolor = ((*srccol++)<<7) & (31<<10);
			dstcolor |= ((*srccol++)<<2) & (31<<5);
			dstcolor |= ((*srccol++)>>3) & 31;
			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBTo565(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint16 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>1;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			Uint16 dstcolor;
			
			dstcolor = ((*srccol++)<<8) & (31<<11);
			dstcolor |= ((*srccol++)<<3) & (63<<5);
			dstcolor |= ((*srccol++)>>3) & 31;
			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBSwap(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint8 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			*dstcol++ = srccol[2];
			*dstcol++ = srccol[1];
			*dstcol++ = srccol[0];
			srccol += 3;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBToARGB(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint32 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>2;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			Uint32	dstcolor;

			dstcolor = (*srccol++)<<16;
			dstcolor |= (*srccol++)<<8;
			dstcolor |= *srccol++;

			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBToABGR(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint32 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>2;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			Uint32	dstcolor;

			dstcolor = *srccol++;
			dstcolor |= (*srccol++)<<8;
			dstcolor |= (*srccol++)<<16;

			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBToBGRA(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint32 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>2;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			Uint32	dstcolor;

			dstcolor = (*srccol++)<<8;
			dstcolor |= (*srccol++)<<16;
			dstcolor |= (*srccol++)<<24;

			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadowRGBToRGBA(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint32 *dstline, *dstcol;
	Uint8 *srcline, *srccol;

	srcline = (Uint8 *)gl_shadow;
	srcpitch = surface->w * gl_pixelsize;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>2;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			Uint32	dstcolor;

			dstcolor = (*srccol++)<<24;
			dstcolor |= (*srccol++)<<16;
			dstcolor |= (*srccol++)<<8;

			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadow8888To555(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint16 *dstline, *dstcol;
	Uint32 *srcline, *srccol;

	srcline = (Uint32 *)gl_shadow;
	srcpitch = (surface->w * gl_pixelsize) >>2;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>1;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;
		for (x=0; x<surface->w; x++) {
			Uint32 srccolor;
			Uint16 dstcolor;
			
			srccolor = *srccol++;
			dstcolor = (srccolor>>9) & (31<<10);
			dstcolor |= (srccolor>>6) & (31<<5);
			dstcolor |= (srccolor>>3) & 31;
			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

static void CopyShadow8888To565(_THIS, SDL_Surface *surface)
{
	int x,y, srcpitch, dstpitch;
	Uint16 *dstline, *dstcol;
	Uint32 *srcline, *srccol;

	srcline = (Uint32 *)gl_shadow;
	srcpitch = (surface->w * gl_pixelsize) >> 2;
	dstline = surface->pixels;
	dstpitch = surface->pitch >>1;
	if (gl_upsidedown) {
		srcline += (surface->h-1)*srcpitch;
		srcpitch = -srcpitch;
	}

	for (y=0; y<surface->h; y++) {
		srccol = srcline;
		dstcol = dstline;

		for (x=0; x<surface->w; x++) {
			Uint32 srccolor;
			Uint16 dstcolor;
			
			srccolor = *srccol++;
			dstcolor = (srccolor>>8) & (31<<11);
			dstcolor |= (srccolor>>5) & (63<<5);
			dstcolor |= (srccolor>>3) & 31;
			*dstcol++ = dstcolor;
		}

		srcline += srcpitch;
		dstline += dstpitch;
	}
}

/*--- Conversions routines in the screen ---*/

static void ConvertNull(_THIS, SDL_Surface *surface)
{
}

static void Convert565To555be(_THIS, SDL_Surface *surface)
{
	int x,y, pitch;
	unsigned short *line, *pixel;

	line = surface->pixels;
	pitch = surface->pitch >> 1;
	for (y=0; y<surface->h; y++) {
		pixel = line;
		for (x=0; x<surface->w; x++) {
			unsigned short color = *pixel;

			*pixel++ = (color & 0x1f)|((color>>1) & 0xffe0);
		}

		line += pitch;
	}
}

static void Convert565To555le(_THIS, SDL_Surface *surface)
{
	int x,y, pitch;
	unsigned short *line, *pixel;

	line = surface->pixels;
	pitch = surface->pitch >>1;
	for (y=0; y<surface->h; y++) {
		pixel = line;
		for (x=0; x<surface->w; x++) {
			unsigned short color = *pixel;

			color = (color & 0x1f)|((color>>1) & 0xffe0);
			*pixel++ = SDL_Swap16(color);
		}

		line += pitch;
	}
}

static void Convert565le(_THIS, SDL_Surface *surface)
{
	int x,y, pitch;
	unsigned short *line, *pixel;

	line = surface->pixels;
	pitch = surface->pitch >>1;
	for (y=0; y<surface->h; y++) {
		pixel = line;
		for (x=0; x<surface->w; x++) {
			unsigned short color = *pixel;

			*pixel++ = SDL_Swap16(color);
		}

		line += pitch;
	}
}

static void ConvertBGRAToABGR(_THIS, SDL_Surface *surface)
{
	int x,y, pitch;
	unsigned long *line, *pixel;

	line = surface->pixels;
	pitch = surface->pitch >>2;
	for (y=0; y<surface->h; y++) {
		pixel = line;
		for (x=0; x<surface->w; x++) {
			unsigned long color = *pixel;

			*pixel++ = (color<<24)|(color>>8);
		}

		line += pitch;
	}
}

#endif /* SDL_VIDEO_OPENGL */