merge w3m-img for framebuffer support

* w3mimg/w3mimg.h: created
* w3mimg/x11/x11_w3mimg.c: created
* w3mimg/fb/fb_w3mimg.c: created
* w3mimgsize.c w3mimgdisplay.c: modified
* configure: modified
* XMakefile: modified
* config.h.dist: updated
From: Fumitoshi UKAI  <ukai@debian.or.jp>

w3m-img for framebuffer support
* http://homepage3.nifty.com/slokar/fb/
* w3mimg/fb/fb.c w3mimg/fb/fb.h
  w3mimg/fb/fb_img.c w3mimg/fb/fb_img.h
  w3mimg/fb/fb_gdkpixbuf.c w3mimg/fb/fb_gdkpixbuf.h
  w3mimg/fb/fb_imlib2.c w3mimg/fb/fb_imlib.h
  w3mimg/fb/readme.txt w3mimg/fb/license.txt: added
From: Hiroshi Kawashima <kei@sm.sony.co.jp>

w3mimg/fb/fb_gdkpixbuf.c

@@ -0,0 +1,128 @@
+/**************************************************************************
+                fb_gdkpixbuf.c 0.2 Copyright (C) 2002, hito
+ **************************************************************************/
+
+#include "fb.h"
+#include "fb_img.h"
+
+static void set_prm(IMAGE *img);
+
+IMAGE *fb_load_image(char *filename, int w, int h)
+{
+  GdkPixbuf *pixbuf;
+  IMAGE *img;
+
+  if(filename == NULL)
+    return NULL;
+
+  img = malloc(sizeof(*img));
+  if(img == NULL)
+    return NULL;
+  
+  pixbuf = gdk_pixbuf_new_from_file(filename);
+  if(pixbuf == NULL){
+    free(img);
+    return NULL;
+  }
+
+  img->pixbuf = pixbuf;
+  set_prm(img);
+
+  fb_resize_image(img, w, h);
+
+  return img;
+}
+
+int fb_draw_image(IMAGE *img, int x, int y, int sx, int sy, int width, int height)
+{
+  int i, j, r, g, b, offset, bpp;
+
+  if(img == NULL)
+    return 1;
+
+  bpp = img->rowstride / img->width;
+  for(j = sy; j < sy + height && j < img->height; j++){
+    offset = j * img->rowstride + bpp * sx;
+    for(i = sx; i < sx + width && i < img->width; i++, offset += bpp){
+      r = img->pixels[offset];
+      g = img->pixels[offset + 1];
+      b = img->pixels[offset + 2];
+      if(img->alpha && img->pixels[offset + 3] == 0)
+	fb_pset(i + x - sx, j + y - sy, bg_r, bg_g, bg_b);
+      else
+	fb_pset(i + x - sx, j + y - sy, r, g, b);
+    }
+  }
+  return 0;
+}
+
+int fb_resize_image(IMAGE *img, int width, int height)
+{
+  GdkPixbuf *pixbuf;
+  if(width < 1 || height < 1 || img == NULL)
+    return 1;
+
+  if(width == img->width && height == img->height)
+    return 0;
+
+  pixbuf = gdk_pixbuf_scale_simple(img->pixbuf, width, height, GDK_INTERP_HYPER);
+  if(pixbuf == NULL)
+    return 1;
+  gdk_pixbuf_finalize(img->pixbuf);
+
+  img->pixbuf = pixbuf;
+  set_prm(img);
+  return 0;
+}
+
+void fb_free_image(IMAGE *img)
+{
+  if(img == NULL)
+    return;
+
+  gdk_pixbuf_finalize(img->pixbuf);
+  free(img);
+}
+
+IMAGE *fb_dup_image(IMAGE *img)
+{
+  GdkPixbuf *pixbuf;
+  IMAGE *new_img;
+
+  if(img == NULL)
+    return NULL;
+
+  new_img = malloc(sizeof(*img));
+  if(new_img == NULL)
+    return NULL;
+
+  pixbuf = gdk_pixbuf_copy(img->pixbuf);
+  if(pixbuf == NULL){
+    free(new_img);
+    return NULL;
+  }
+
+  new_img->pixbuf = pixbuf;
+  set_prm(new_img);
+  return new_img;
+}
+
+int fb_rotate_image(IMAGE *img, int angle)
+{
+  return 1;
+}
+
+static void set_prm(IMAGE *img)
+{
+  GdkPixbuf *pixbuf;
+
+  if(img == NULL)
+    return;
+  pixbuf = img->pixbuf;
+
+  img->pixels = gdk_pixbuf_get_pixels(pixbuf);
+  img->width  = gdk_pixbuf_get_width(pixbuf);
+  img->height = gdk_pixbuf_get_height(pixbuf);
+  img->alpha  = gdk_pixbuf_get_has_alpha(pixbuf);
+  img->rowstride = gdk_pixbuf_get_rowstride(pixbuf);
+}