ximutil.c

早期freebsd实现

static unsigned long _XGetPixel8 (ximage, x, y)
    register XImage *ximage;
    int x;
    int y;
{
	unsigned char pixel;

	if ((ximage->format == ZPixmap) && (ximage->bits_per_pixel == 8)) {
	    pixel = ((unsigned char *)ximage->data)
			[y * ximage->bytes_per_line + x];
	    if (ximage->depth != 8)
		pixel &= low_bits_table[ximage->depth];
	    return pixel;
	} else {
	    _XInitImageFuncPtrs(ximage);
	    return XGetPixel(ximage, x, y);
	}
}

static unsigned long _XGetPixel1 (ximage, x, y)
    register XImage *ximage;
    int x;
    int y;
{
	unsigned char bit;
	int xoff, yoff;

	if ((ximage->depth == 1) &&
	    (ximage->byte_order == ximage->bitmap_bit_order)) {
	    xoff = x + ximage->xoffset;
	    yoff = y * ximage->bytes_per_line + (xoff >> 3);
	    xoff &= 7;
	    if (ximage->bitmap_bit_order == MSBFirst)
	        bit = 0x80 >> xoff;
	    else
		bit = 1 << xoff;
	    return (ximage->data[yoff] & bit) ? 1 : 0;
	} else {
	    _XInitImageFuncPtrs(ximage);
	    return XGetPixel(ximage, x, y);
	}
}
	
/*
 * PutPixel
 * 
 * Overwrites the specified pixel.  The X and Y coordinates are relative to 
 * the origin (upper left [0,0]) of the image.  The input pixel value must be
 * in normalized format, i.e. the LSB of the long is the LSB of the pixel.
 * The algorithm used is:
 *
 *	copy the destination bitmap_unit or Zpixel to temp
 *	normalize temp if needed
 *	copy the pixel bits into the temp
 *	renormalize temp if needed
 *	copy the temp back into the destination image data
 *
 */

static int _XPutPixel (ximage, x, y, pixel)
    register XImage *ximage;
    int x;
    int y;
    unsigned long pixel;

{
	unsigned long px, npixel;
	register char *src;
	register char *dst;
	register int i;
	int j, nbytes;
	long plane;

	if (ximage->depth == 4)
	    pixel &= 0xf;
        npixel = pixel;
	for (i=0, px=pixel; i<sizeof(unsigned long); i++, px>>=8)
	    ((unsigned char *)&pixel)[i] = px;
	if (ximage->depth == 1) {
		src = &ximage->data[XYINDEX(x, y, ximage)];
		dst = (char *)&px;
		px = 0;
		nbytes = ximage->bitmap_unit >> 3;
		for (i = nbytes; --i >= 0; ) *dst++ = *src++;
		XYNORMALIZE(&px, ximage);
		i = ((x + ximage->xoffset) % ximage->bitmap_unit);
		_putbits ((char *)&pixel, i, 1, (char *)&px);
		XYNORMALIZE(&px, ximage);
		src = (char *) &px;
		dst = &ximage->data[XYINDEX(x, y, ximage)];
		for (i = nbytes; --i >= 0; ) *dst++ = *src++;
	} else if (ximage->format == XYPixmap) {
		plane = (ximage->bytes_per_line * ximage->height) *
		    (ximage->depth - 1); /* do least signif plane 1st */
		nbytes = ximage->bitmap_unit >> 3;
		for (j = ximage->depth; --j >= 0; ) {
		    src = &ximage->data[XYINDEX(x, y, ximage) + plane];
		    dst = (char *) &px;
		    px = 0;
		    for (i = nbytes; --i >= 0; ) *dst++ = *src++;
		    XYNORMALIZE(&px, ximage);
		    i = ((x + ximage->xoffset) % ximage->bitmap_unit);
		    _putbits ((char *)&pixel, i, 1, (char *)&px);
		    XYNORMALIZE(&px, ximage);
		    src = (char *)&px;
		    dst = &ximage->data[XYINDEX(x, y, ximage) + plane];
		    for (i = nbytes; --i >= 0; ) *dst++ = *src++;
		    npixel = npixel >> 1;
		    for (i=0, px=npixel; i<sizeof(unsigned long); i++, px>>=8)
			((unsigned char *)&pixel)[i] = px;
		    plane = plane - (ximage->bytes_per_line * ximage->height);
		}
	} else if (ximage->format == ZPixmap) {
		src = &ximage->data[ZINDEX(x, y, ximage)];
		dst = (char *)&px;
		px = 0;
		nbytes = (ximage->bits_per_pixel + 7) >> 3;
		for (i = nbytes; --i >= 0; ) *dst++ = *src++;
		ZNORMALIZE(&px, ximage);
		_putbits ((char *)&pixel, 
			  (x * ximage->bits_per_pixel) & 7, 
			  ximage->bits_per_pixel, (char *)&px);
		ZNORMALIZE(&px, ximage);
		src = (char *)&px;
		dst = &ximage->data[ZINDEX(x, y, ximage)];
		for (i = nbytes; --i >= 0; ) *dst++ = *src++;
	} else {
		return 0; /* bad image */
	}
	return 1;
}

static int _XPutPixel32 (ximage, x, y, pixel)
    register XImage *ximage;
    int x;
    int y;
    unsigned long pixel;
{
	unsigned char *addr;

	if ((ximage->format == ZPixmap) && (ximage->bits_per_pixel == 32)) {
	    addr = &((unsigned char *)ximage->data)
			[y * ximage->bytes_per_line + (x << 2)];
#ifndef WORD64
	    if (*((char *)&byteorderpixel) == ximage->byte_order)
		*((unsigned long *)addr) = pixel;
	    else
#endif
	    if (ximage->byte_order == MSBFirst) {
		addr[0] = pixel >> 24;
		addr[1] = pixel >> 16;
		addr[2] = pixel >> 8;
		addr[3] = pixel;
	    } else {
		addr[3] = pixel >> 24;
		addr[2] = pixel >> 16;
		addr[1] = pixel >> 8;
		addr[0] = pixel;
	    }
	    return 1;
	} else {
	    _XInitImageFuncPtrs(ximage);
	    return XPutPixel(ximage, x, y, pixel);
	}
}

static int _XPutPixel16 (ximage, x, y, pixel)
    register XImage *ximage;
    int x;
    int y;
    unsigned long pixel;
{
	unsigned char *addr;

	if ((ximage->format == ZPixmap) && (ximage->bits_per_pixel == 16)) {
	    addr = &((unsigned char *)ximage->data)
			[y * ximage->bytes_per_line + (x << 1)];
	    if (ximage->byte_order == MSBFirst) {
		addr[0] = pixel >> 8;
		addr[1] = pixel;
	    } else {
		addr[1] = pixel >> 8;
		addr[0] = pixel;
	    }
	    return 1;
	} else {
	    _XInitImageFuncPtrs(ximage);
	    return XPutPixel(ximage, x, y, pixel);
	}
}

static int _XPutPixel8 (ximage, x, y, pixel)
    register XImage *ximage;
    int x;
    int y;
    unsigned long pixel;
{
	if ((ximage->format == ZPixmap) && (ximage->bits_per_pixel == 8)) {
	    ximage->data[y * ximage->bytes_per_line + x] = pixel;
	    return 1;
	} else {
	    _XInitImageFuncPtrs(ximage);
	    return XPutPixel(ximage, x, y, pixel);
	}
}

static int _XPutPixel1 (ximage, x, y, pixel)
    register XImage *ximage;
    int x;
    int y;
    unsigned long pixel;
{
	unsigned char bit;
	int xoff, yoff;

	if ((ximage->depth == 1) &&
	    (ximage->byte_order == ximage->bitmap_bit_order)) {
	    xoff = x + ximage->xoffset;
	    yoff = y * ximage->bytes_per_line + (xoff >> 3);
	    xoff &= 7;
	    if (ximage->bitmap_bit_order == MSBFirst)
		bit = 0x80 >> xoff;
	    else
		bit = 1 << xoff;
	    if (pixel & 1)
		ximage->data[yoff] |= bit;
	    else
		ximage->data[yoff] &= ~bit;
	    return 1;
	} else {
	    _XInitImageFuncPtrs(ximage);
	    return XPutPixel(ximage, x, y, pixel);
	}
}

/*
 * SubImage
 * 
 * Creates a new image that is a subsection of an existing one.
 * Allocates the memory necessary for the new XImage data structure. 
 * Pointer to new image is returned.  The algorithm used is repetitive
 * calls to get and put pixel.
 *
 */

static XImage *_XSubImage (ximage, x, y, width, height)
    XImage *ximage;
    register int x;	/* starting x coordinate in existing image */
    register int y;	/* starting y coordinate in existing image */
    unsigned int width;	/* width in pixels of new subimage */
    unsigned int height;/* height in pixels of new subimage */

{
	register XImage *subimage;
	int dsize;
	register int row, col;
	register unsigned long pixel;
	char *data;

	if ((subimage = (XImage *) Xcalloc (1, sizeof (XImage))) == NULL)
	    return (XImage *) NULL;
	subimage->width = width;
	subimage->height = height;
	subimage->xoffset = 0;
	subimage->format = ximage->format;
	subimage->byte_order = ximage->byte_order;
	subimage->bitmap_unit = ximage->bitmap_unit;
	subimage->bitmap_bit_order = ximage->bitmap_bit_order;
	subimage->bitmap_pad = ximage->bitmap_pad;
	subimage->bits_per_pixel = ximage->bits_per_pixel;
	subimage->depth = ximage->depth;
	/*
	 * compute per line accelerator.
	 */
	if (subimage->format == ZPixmap) 	
	    subimage->bytes_per_line = 
		ROUNDUP(subimage->bits_per_pixel * width,
			subimage->bitmap_pad);
	else
	    subimage->bytes_per_line =
		ROUNDUP(width, subimage->bitmap_pad);
	subimage->obdata = NULL;
	_XInitImageFuncPtrs (subimage);
	dsize = subimage->bytes_per_line * height;
	if (subimage->format == XYPixmap) dsize = dsize * subimage->depth;
	if (((data = Xcalloc (1, (unsigned) dsize)) == NULL) && (dsize > 0)) {
	    Xfree((char *) subimage);
	    return (XImage *) NULL;
	}
	subimage->data = data;

	/*
	 * Test for cases where the new subimage is larger than the region
	 * that we are copying from the existing data.  In those cases,
	 * copy the area of the existing image, and allow the "uncovered"
	 * area of new subimage to remain with zero filled pixels.
	 */
	if (height > ximage->height - y ) height = ximage->height - y;
	if (width > ximage->width - x ) width = ximage->width - x;

	for (row = y; row < (y + height); row++) {
	    for (col = x; col < (x + width); col++) {
		pixel = XGetPixel(ximage, col, row);
		XPutPixel(subimage, (col - x), (row - y), pixel);
	    }
	}
	return subimage;
}


/*
 * SetImage
 * 
 * Overwrites a section of one image with all of the data from another.
 * If the two images are not of the same format (i.e. XYPixmap and ZPixmap),
 * the image data is converted to the destination format.  The following
 * restrictions apply:
 *
 *	1. The depths of the source and destination images must be equal.
 *
 *	2. If the height of the source image is too large to fit between
 *	   the specified y starting point and the bottom of the image,
 *	   then scanlines are truncated on the bottom.
 *
 *	3. If the width of the source image is too large to fit between
 *	   the specified x starting point and the end of the scanline,
 *	   then pixels are truncated on the right.
 * 
 * The images need not have the same bitmap_bit_order, byte_order,
 * bitmap_unit, bits_per_pixel, bitmap_pad, or xoffset.
 *
 */

int _XSetImage (srcimg, dstimg, x, y)
    XImage *srcimg;
    register XImage *dstimg;
    register int x;
    register int y;

{
	register unsigned long pixel;
	register int row, col;
	int width, height, startrow, startcol;
	if (x < 0) {
	    startcol = -x;
	    x = 0;
	} else
	    startcol = 0;
	if (y < 0) {
	    startrow = -y;
	    y = 0;
	} else
	    startrow = 0;
	width = dstimg->width - x;
	if (srcimg->width < width)
	    width = srcimg->width;
	height = dstimg->height - y;
	if (srcimg->height < height)
	    height = srcimg->height;

	/* this is slow, will do better later */
	for (row = startrow; row < height; row++) {
	    for (col = startcol; col < width; col++) {
		pixel = XGetPixel(srcimg, col, row);
		XPutPixel(dstimg, x + col, y + row, pixel);
	    }
	}
	return 1;
}

/*
 * AddPixel
 * 
 * Adds a constant value to every pixel in a pixmap.
 *
 */

static _XAddPixel (ximage, value)
    register XImage *ximage;
    register long value;
{
	register int x;
	register int y;

	if (!value)
	    return;
	if (ximage->depth == 1) {
	    /* The only value that we can add here to an XYBitmap
	     * is one.  Since 1 + value = ~value for one bit wide
	     * data, we do this quickly by taking the ones complement
	     * of the entire bitmap data (offset and pad included!).
	     * Note that we don't need to be concerned with bit or
	     * byte order at all.
	     */
	    register unsigned char *dp = (unsigned char *) ximage->data;
	    x = ximage->bytes_per_line * ximage->height;
	    while (--x >= 0) {
		*dp = ~*dp;
		dp++;
	    }
	} else if ((ximage->format == ZPixmap) &&
		   (ximage->bits_per_pixel == 8)) {
	    register unsigned char *dp = (unsigned char *) ximage->data;
	    x = ximage->bytes_per_line * ximage->height;
	    while (--x >= 0)
		*dp++ += value;
#ifndef WORD64
	} else if ((ximage->format == ZPixmap) &&
		   (ximage->bits_per_pixel == 16) &&
		   (*((char *)&byteorderpixel) == ximage->byte_order)) {
	    register unsigned short *dp = (unsigned short *) ximage->data;
	    x = (ximage->bytes_per_line >> 1) * ximage->height;
	    while (--x >= 0)
		*dp++ += value;
	} else if ((ximage->format == ZPixmap) &&
		   (ximage->bits_per_pixel == 32) &&
		   (*((char *)&byteorderpixel) == ximage->byte_order)) {
	    register unsigned long *dp = (unsigned long *) ximage->data;
	    x = (ximage->bytes_per_line >> 2) * ximage->height;
	    while (--x >= 0)
		*dp++ += value;
#endif
	} else {
	    for (y = ximage->height; --y >= 0; ) {
		for (x = ximage->width; --x >= 0; ) {
		    register unsigned long pixel = XGetPixel(ximage, x, y);
		    pixel = pixel + value;
		    XPutPixel(ximage, x, y, pixel);
		}
	    }
	}
}

/*
 * This routine initializes the image object function pointers.  The
 * intent is to provide native (i.e. fast) routines for native format images
 * only using the generic (i.e. slow) routines when fast ones don't exist.
 * However, with the current rather botched external interface, clients may
 * have to mung image attributes after the image gets created, so the fast
 * routines always have to check to make sure the optimization is still
 * valid, and reinit the functions if not.
 */
_XInitImageFuncPtrs (image)
    register XImage *image;
{
	image->f.create_image = XCreateImage;
	image->f.destroy_image = _XDestroyImage;
	if ((image->format == ZPixmap) && (image->bits_per_pixel == 8)) {
	    image->f.get_pixel = _XGetPixel8;
	    image->f.put_pixel = _XPutPixel8;
	} else if ((image->depth == 1) &&
		   (image->byte_order == image->bitmap_bit_order)) {
	    image->f.get_pixel = _XGetPixel1;
	    image->f.put_pixel = _XPutPixel1;
	} else if ((image->format == ZPixmap) &&
		   (image->bits_per_pixel == 32)) {
	    image->f.get_pixel = _XGetPixel32;
	    image->f.put_pixel = _XPutPixel32;
	} else if ((image->format == ZPixmap) &&
		   (image->bits_per_pixel == 16)) {
	    image->f.get_pixel = _XGetPixel16;
	    image->f.put_pixel = _XPutPixel16;
	} else {
	    image->f.get_pixel = _XGetPixel;
	    image->f.put_pixel = _XPutPixel;
	}
	image->f.sub_image = _XSubImage;
/*	image->f.set_image = _XSetImage;*/
	image->f.add_pixel = _XAddPixel;
}