Initial revision

wrlib/xpixmap.c

@@ -0,0 +1,169 @@
+/* xpixmap.c - Make RImage from Pixmap or XImage
+ * 
+ *  Raster graphics library
+ *
+ *  Copyright (c) 1997 Alfredo K. Kojima 
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *  
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *  
+ *  You should have received a copy of the GNU Library General Public
+ *  License along with this library; if not, write to the Free
+ *  Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <config.h>
+
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+#include "wraster.h"
+
+
+
+static int
+get_shifts(unsigned long mask)
+{
+    int i=0;
+    
+    while (mask) {
+	mask>>=1;
+	i++;
+    }
+    return i;
+}
+
+
+RImage*
+RCreateImageFromXImage(RContext *context, XImage *image, XImage *mask)
+{
+    RImage *img;
+    int x, y;
+    unsigned long pixel;
+    unsigned char *r, *g, *b, *a;
+    int rshift, gshift, bshift;
+    int rmask, gmask, bmask;
+
+    RErrorString[0] = 0;
+    
+    assert(image!=NULL);
+    assert(image->format==ZPixmap);
+    assert(!mask || mask->format==ZPixmap);
+    
+    img = RCreateImage(image->width, image->height, mask!=NULL);
+    if (!img) {
+	return NULL;
+    }
+      
+
+    /* I don't know why, but XGetImage() for pixmaps don't set the
+     * {red,green,blue}_mask values correctly. This will not
+     * work for imageis of depth different than the root window 
+     * one used in wrlib
+     */ 
+    if (context->depth==image->depth) {
+     	rmask = context->visual->red_mask;
+    	gmask = context->visual->green_mask;
+    	bmask = context->visual->blue_mask;
+    } else {
+    	rmask = image->red_mask;
+    	gmask = image->green_mask;
+    	bmask = image->blue_mask;
+    }
+
+    /* how many bits to shift to normalize the color into 8bpp */
+    rshift = get_shifts(rmask) - 8;
+    gshift = get_shifts(gmask) - 8;
+    bshift = get_shifts(bmask) - 8;
+
+    r = img->data[0];
+    g = img->data[1];
+    b = img->data[2];
+    a = img->data[3];
+
+#define NORMALIZE_RED(pixel)	((rshift>0) ? ((pixel) & rmask) >> rshift \
+					: ((pixel) & rmask) << -rshift)
+#define NORMALIZE_GREEN(pixel)	((gshift>0) ? ((pixel) & gmask) >> gshift \
+					: ((pixel) & gmask) << -gshift)
+#define NORMALIZE_BLUE(pixel)	((bshift>0) ? ((pixel) & bmask) >> bshift \
+					: ((pixel) & bmask) << -bshift)
+
+    for (y = 0; y < image->height; y++) {
+	for (x = 0; x < image->width; x++) {
+	    pixel = XGetPixel(image, x, y);
+	    *(r++) = NORMALIZE_RED(pixel);
+	    *(g++) = NORMALIZE_GREEN(pixel);
+	    *(b++) = NORMALIZE_BLUE(pixel);
+	}
+    }
+
+    if (mask && a) {
+	for (y = 0; y < mask->height; y++) {
+	    for (x = 0; x < mask->width; x++) {
+		if (XGetPixel(mask, x, y)) {
+		    *(a++) = 0xff;
+		} else {
+		    *(a++) = 0xff;
+		}
+	    }
+	}
+    }
+    return img;
+}
+
+
+
+RImage*
+RCreateImageFromDrawable(RContext *context, Drawable drawable, Pixmap mask)
+{
+    RImage *image;
+    XImage *pimg, *mimg;
+    unsigned int w, h, bar;
+    int foo;
+    Window baz;
+
+    RErrorString[0] = 0;
+
+    assert(drawable!=None);
+    
+    if (!XGetGeometry(context->dpy, drawable, &baz, &foo, &foo, 
+		      &w, &h, &bar, &bar)) {
+	printf("wrlib:invalid window or pixmap passed to RCreateImageFromPixmap\n");
+	return NULL;
+    }
+    pimg = XGetImage(context->dpy, drawable, 0, 0, w, h, AllPlanes, 
+		     ZPixmap);
+    
+    if (!pimg) {
+	sprintf(RErrorString, "could not get image");
+	return NULL;
+    }
+    mimg = NULL;
+    if (mask) {
+	if (XGetGeometry(context->dpy, mask, &baz, &foo, &foo, 
+			  &w, &h, &bar, &bar)) {
+	    mimg = XGetImage(context->dpy, mask, 0, 0, w, h, AllPlanes, 
+			     ZPixmap);
+	}
+    }
+
+    image = RCreateImageFromXImage(context, pimg, mimg);
+
+    XDestroyImage(pimg);
+    if (mimg)
+      XDestroyImage(mimg);
+
+    return image;
+}