dev2gif.c

在EM85XX

				 &WinAttr);
	    ScreenXMax = WinAttr.width;
	    ScreenYMax = WinAttr.height;

	    XImg = XGetImage((Display *) ReqGraphMode2,
			     (Window) ReqGraphMode1,
			     0, 0, ScreenXMax - 1, ScreenYMax - 1,
			     AllPlanes, XYPixmap);

	    GlblGifBuffer = (GifByteType *) malloc(sizeof(GifByteType) *
						ScreenXMax * ScreenYMax);

	    /* Scan the image for all different colors exists. */
	    for (i = 0; i < 256; i++) XColorTable[i].pixel = 0;
	    k = FALSE;
 	    for (i = 0; i < ScreenXMax; i++)
		for (j = 0; j < ScreenYMax; j++) {
		    XPixel = XGetPixel(XImg, i, j);
		    if (XPixel > 255) {
			if (!k) {
			    /* Make sure we state it once only.*/
			    fprintf(stderr, "X Color table - truncated.\n");
			    k = TRUE;
			}
			XPixel = 255;
		    }
		    XColorTable[XPixel].pixel = XPixel;
		}
	    /* Find the RGB representation of the colors. */
	    XQueryColors((Display *) ReqGraphMode2,
			 (Colormap) ReqGraphMode3,
			 XColorTable,
			 256);
	    /* Count number of active colors (Note color 0 is always in)    */
	    /* and create the Gif color map from it.			    */
	    ColorMap = MakeMapObject(256, ColorMap256);
	    ColorMap->Colors[0].Red = ColorMap->Colors[0].Green = ColorMap->Colors[0].Blue = 0;
	    for (i = j = 1; i < 256; i++)
		if (XColorTable[i].pixel) {
		    ColorMap->Colors[j].Red = XColorTable[i].red / 256;
		    ColorMap->Colors[j].Green = XColorTable[i].green / 256;
		    ColorMap->Colors[j].Blue = XColorTable[i].blue / 256;
		    /* Save the X color index into the Gif table: */
		    XColorTable[i].pixel = j++;
		}
	    /* and set the number of colors in the Gif color map. */
	    for	(ScreenColorBits = 1;
		 (1 << ScreenColorBits) < j && ScreenColorBits < 8;
		 ScreenColorBits++);

	    /* Prepare the Gif image buffer as indices into the Gif color   */
	    /* map from the X image.					    */
	    GlblGifBufferPtr = GlblGifBuffer;
	    for (i = 0; i < ScreenXMax; i++)
		for (j = 0; j < ScreenYMax; j++)
		    *GlblGifBufferPtr++ =
			XColorTable[XGetPixel(XImg, j, i) & 0xff].pixel;
	    XDestroyImage(XImg);

	    GlblGifBufferPtr = GlblGifBuffer;
	    ColorMap = MakeMapObject(256, ColorMap256);
	    break;
#endif /* __X11__ */
	default:
	    return -1;
    }

    ScanLine = (GifPixelType *) malloc(sizeof(GifPixelType) * ScreenXMax);

    GraphDriver = ReqGraphDriver;
    GraphMode = ReqGraphMode1;

    if ((GifFile = EGifOpenFileName(FileName, FALSE)) == NULL ||
	EGifPutScreenDesc(GifFile, ScreenXMax, ScreenYMax, ScreenColorBits,
			  0, ColorMap) == GIF_ERROR ||
	EGifPutImageDesc(GifFile, 0, 0, ScreenXMax, ScreenYMax, FALSE,
			 NULL) == GIF_ERROR) {
	free((char *) ScanLine);
#if defined(__SGI_GL__) || defined(__X11__)
	free((char *) GlblGifBuffer);
#endif
	return HandleGifError(GifFile);
    }

    for (i = 0; i < ScreenYMax; i++) {
	GetScanLine(ScanLine, i);
	if (EGifPutLine(GifFile, ScanLine, ScreenXMax) == GIF_ERROR) {
	    free((char *) ScanLine);
#if defined(__SGI_GL__) || defined(__X11__)
	    free((char *) GlblGifBuffer);
#endif
	    return HandleGifError(GifFile);
	}
    }

    if (EGifCloseFile(GifFile) == GIF_ERROR) {
	free((char *) ScanLine);
#if defined(__SGI_GL__) || defined(__X11__)
	free((char *) GlblGifBuffer);
#endif
	return HandleGifError(GifFile);
    }

    free((char *) ScanLine);
#if defined(__SGI_GL__) || defined(__X11__)
    free((char *) GlblGifBuffer);
#endif
    return 0;
}

#ifdef __SGI_GL__
/******************************************************************************
* Quantize the given 24 bit (8 per RGB) into 256 colors.		      *
******************************************************************************/
static int QuantizeRGBBuffer(int Width, int Height, long *RGBBuffer,
			      GifColorType *ColorMap, GifByteType *GIFBuffer)
{
    int i;
    GifByteType *RedInput, *GreenInput, *BlueInput;

    /* Convert the RGB Buffer into 3 seperated buffers: */
    RedInput = (GifByteType *) malloc(sizeof(GifByteType) * Width * Height);
    GreenInput = (GifByteType *) malloc(sizeof(GifByteType) * Width * Height);
    BlueInput = (GifByteType *) malloc(sizeof(GifByteType) * Width * Height);

    for (i = 0; i < Width * Height; i++) {
	RedInput[i] = RGBBuffer[i] & 0xff;
	GreenInput[i] = (RGBBuffer[i] >> 8) & 0xff;
	BlueInput[i] = (RGBBuffer[i] >> 16) & 0xff;
    }
    for (i = 0; i < 256; i++)
	ColorMap[i].Red = ColorMap[i].Green = ColorMap[i].Blue = 0;

    i = 256;
    QuantizeBuffer(Width, Height, &i,
		   RedInput, GreenInput, BlueInput,
		   GIFBuffer, ColorMap);

    free(RedInput);
    free(GreenInput);
    free(BlueInput);

    return i;			   /* Real number of colors in color table. */
}
#endif /* __SGI_GL__ */

/******************************************************************************
* Update the given scan line buffer with the pixel levels of the Y line.      *
* This routine is device specific, so make sure you know was you are doing    *
******************************************************************************/
static void GetScanLine(GifPixelType *ScanLine, int Y)
{
    unsigned char ScreenByte;
    int i, j, k;
    unsigned int BufferOffset, Bit;
#ifdef __MSDOS__
    union REGS InRegs, OutRegs;
#endif /* __MSDOS__ */

    switch (GraphDriver) {
#ifdef __MSDOS__
	case HERCMONO:
	    BufferOffset = 0x2000 * (Y % 4) + (Y / 4) * (ScreenXMax / 8);
	    /* In one scan lines we have ScreenXMax / 8 bytes: */
	    for (i = 0, k = 0; i < ScreenXMax / 8; i++) {
		ScreenByte = (unsigned char) peekb(ScreenBase, BufferOffset++);
		for (j = 0, Bit = 0x80; j < 8; j++) {
		    ScanLine[k++] = (ScreenByte & Bit ? 1 : 0);
		    Bit >>= 1;
		}
	    }
	    break;
	case EGA:
	case EGA64:
	case EGAMONO:
	case VGA:
	case SVGA_SPECIAL:
	    InRegs.x.dx = Y;
	    InRegs.h.bh = 0;
    	    InRegs.h.ah = 0x0d;				   /* BIOS Read dot. */
	    for (i = 0; i < ScreenXMax; i++) {
	    	InRegs.x.cx = i;
		int86(0x10, &InRegs, &OutRegs);
	    	ScanLine[i] = OutRegs.h.al;
	    }

	    /* Makr this line as done by putting a xored dot on the left. */
	    InRegs.x.dx = Y;
	    InRegs.h.bh = 0;
	    InRegs.h.ah = 0x0c;		       /* BIOS Write dot (xor mode). */
	    InRegs.h.al = 0x81;			        /* Xor with color 1. */
	    InRegs.x.cx = 0;
	    int86(0x10, &InRegs, &OutRegs);
	    InRegs.x.dx = Y;
	    InRegs.h.bh = 0;
	    InRegs.h.ah = 0x0c;		       /* BIOS Write dot (xor mode). */
	    InRegs.h.al = 0x81;			        /* Xor with color 1. */
	    InRegs.x.cx = 1;
	    int86(0x10, &InRegs, &OutRegs);

	    if (Y == ScreenYMax - 1) {/* Last row - clear all marks we made. */
		for (i = 0; i < ScreenYMax; i++) {
		    InRegs.h.bh = 0;
		    InRegs.h.ah = 0x0c;	       /* BIOS Write dot (xor mode). */
		    InRegs.h.al = 0x81;		   /* Xor back with color 1. */
		    InRegs.x.dx = i;
		    InRegs.x.cx = 0;
		    int86(0x10, &InRegs, &OutRegs);
		    InRegs.h.bh = 0;
		    InRegs.h.ah = 0x0c;	       /* BIOS Write dot (xor mode). */
		    InRegs.h.al = 0x81;		   /* Xor back with color 1. */
		    InRegs.x.dx = i;
		    InRegs.x.cx = 1;
		    int86(0x10, &InRegs, &OutRegs);
                }
	    }
	    break;
#endif /* __MSDOS__ */
#ifdef __SGI_GL__
	case GIF_DUMP_SGI_WINDOW:
	    memcpy(ScanLine, GlblGifBufferPtr, ScreenXMax * sizeof(GifPixelType));
	    GlblGifBufferPtr -= ScreenXMax;
	    break;
#endif /* __SGI_GL__ */
#ifdef __X11__
	case GIF_DUMP_X_WINDOW:
	    memcpy(ScanLine, GlblGifBufferPtr, ScreenXMax * sizeof(GifPixelType));
	    GlblGifBufferPtr += ScreenXMax;
	    break;
#endif /* __X11__ */
	default:
	    break;
    }
}

/******************************************************************************
* Handle last GIF error. Try to close the file and free all allocated memory. *
******************************************************************************/
static int HandleGifError(GifFileType *GifFile)
{
    int i = GifLastError();

    if (EGifCloseFile(GifFile) == GIF_ERROR) {
	GifLastError();
    }
    return i;
}