Load-at-size functionality for gdk-pixbuf.

22 files changed, 313 insertions, 107 deletions

diff --git a/docs/reference/ChangeLog b/docs/reference/ChangeLog
index 8bb545817b..0f75a3466c 100644
--- a/docs/reference/ChangeLog
+++ b/docs/reference/ChangeLog
@@ -1,3 +1,10 @@
+2002-07-07  Matthias Clasen  <maclas@gmx.de>
+
+	* gdk-pixbuf/gdk-pixbuf-sections.txt, 
+	gdk-pixbuf/tmpl/gdk-pixbuf-loader.sgml,
+	gdk-pixbuf/tmpl/module_interface.sgml: Updates for
+	load-at-size functionality.
+
 Tue Jun 18 17:02:48 2002  Owen Taylor  <otaylor@redhat.com>
 
 	* gdk/gdk-sections.txt: Fix for cursor screen => display
diff --git a/docs/reference/gdk-pixbuf/Makefile.am b/docs/reference/gdk-pixbuf/Makefile.am
index aa568b9840..1f9a3f36c1 100644
--- a/docs/reference/gdk-pixbuf/Makefile.am
+++ b/docs/reference/gdk-pixbuf/Makefile.am
@@ -13,7 +13,7 @@ DOC_SOURCE_DIR=../../../gdk-pixbuf
 SCAN_OPTIONS=--source-dir=../../../contrib/gdk-pixbuf-xlib --deprecated-guards="GDK_PIXBUF_ENABLE_BROKEN|GDK_PIXBUF_DISABLE_DEPRECATED"
 
 # Extra options to supply to gtkdoc-mkdb
-MKDB_OPTIONS=--sgml-mode --source-dir=../../../contrib/gdk-pixbuf-xlib --output-format=xml
+MKDB_OPTIONS=--main-sgml-file=$(DOC_MAIN_SGML_FILE) --sgml-mode --source-dir=../../../contrib/gdk-pixbuf-xlib --output-format=xml
 
 # Extra options to supply to gtkdoc-fixref
 FIXXREF_OPTIONS=
diff --git a/docs/reference/gdk-pixbuf/gdk-pixbuf-sections.txt b/docs/reference/gdk-pixbuf/gdk-pixbuf-sections.txt
index a41778b36e..1f5af2b87d 100644
--- a/docs/reference/gdk-pixbuf/gdk-pixbuf-sections.txt
+++ b/docs/reference/gdk-pixbuf/gdk-pixbuf-sections.txt
@@ -149,6 +149,7 @@ gdk_interp_type_get_type
 gdk_pixbuf_loader_new
 gdk_pixbuf_loader_new_with_type
 gdk_pixbuf_loader_write
+gdk_pixbuf_loader_set_size
 gdk_pixbuf_loader_get_pixbuf
 gdk_pixbuf_loader_get_animation
 gdk_pixbuf_loader_close
@@ -168,6 +169,7 @@ gdk_pixbuf_loader_get_type
 <TITLE>Module Interface</TITLE>
 <FILE>module_interface</FILE>
 ModuleFillVtableFunc
+ModuleSizeFunc
 ModulePreparedNotifyFunc
 ModuleUpdatedNotifyFunc
 GdkPixbufModule
diff --git a/docs/reference/gdk-pixbuf/tmpl/gdk-pixbuf-loader.sgml b/docs/reference/gdk-pixbuf/tmpl/gdk-pixbuf-loader.sgml
index dbdfa95c20..fb6275b5ed 100644
--- a/docs/reference/gdk-pixbuf/tmpl/gdk-pixbuf-loader.sgml
+++ b/docs/reference/gdk-pixbuf/tmpl/gdk-pixbuf-loader.sgml
@@ -21,21 +21,28 @@ Application-driven progressive image loading.
     To use #GdkPixbufLoader to load an image, just create a new one,
     and call gdk_pixbuf_loader_write() to send the data to it.  When
     done, gdk_pixbuf_loader_close() should be called to end the stream
-    and finalize everything.  The loader will emit two important
+    and finalize everything.  The loader will emit three important
     signals throughout the process.  The first, "<link
-    linkend="GdkPixbufLoader-area-prepared">area_prepared</link>",
+    linkend="GdkPixbufLoader-size-prepared">size_prepared</link>",
     will be called as soon as the image has enough information to
-    determine the size of the image to be used.  It will pass a
-    @GdkPixbuf in.  If you want to use it, you can simply ref it.  In
-    addition, no actual information will be passed in yet, so the
+    determine the size of the image to be used. If you want to scale
+    the image while loading it, you can call gdk_pixbuf_loader_set_size()
+    in response to this signal.
+    </para>
+
+    <para>The second signal, "<link
+    linkend="GdkPixbufLoader-area-prepared">area_prepared</link>",
+    will be called as soon as the pixbuf of the desired has been 
+    allocated.  You can obtain it by calling gdk_pixbuf_loader_get_pixbuf(). 
+    If you want to use it, simply ref it.  
+    In addition, no actual information will be passed in yet, so the
     pixbuf can be safely filled with any temporary graphics (or an
-    initial color) as needed.  You can also call the
-    gdk_pixbuf_loader_get_pixbuf() once this signal has been emitted
-    and get the same pixbuf.
+    initial color) as needed.  You can also call
+    gdk_pixbuf_loader_get_pixbuf() later and get the same pixbuf.
   </para>
 
   <para>
-    The other signal, "<link
+    The last signal, "<link
     linkend="GdkPixbufLoader-area-updated">area_updated</link>" gets
     called every time a region is updated.  This way you can update a
     partially completed image.  Note that you do not know anything
@@ -119,19 +126,23 @@ Application-driven progressive image loading.
 @error: 
 @Returns: 
 
-
-<!-- ##### SIGNAL GdkPixbufLoader::area-prepared ##### -->
+<!-- ##### SIGNAL GdkPixbufLoader::size-prepared ##### -->
   <para>
     This signal is emitted when the pixbuf loader has been fed the
-    initial amount of data that is required to figure out the size and
-    format of the image that it will create.  After this signal is
-    emitted, applications can call gdk_pixbuf_loader_get_pixbuf() to
-    fetch the partially-loaded pixbuf.
+    initial amount of data that is required to figure out the size
+    of the image that it will create.  Applications can call  
+    gdk_pixbuf_loader_set_size() in response to this signal to set
+    the desired size to which the image should be scaled.
   </para>
+@width: the original width of the image
+@height: the original height of the image
 
-@gdkpixbufloader: the object which received the signal.
-<!-- # Unused Parameters # -->
-@loader: Loader which emitted the signal.
+<!-- ##### SIGNAL GdkPixbufLoader::area-prepared ##### -->
+  <para>
+    This signal is emitted when the pixbuf loader has allocated the pixbuf
+    in the desired size.  After this signal is emitted, applications can 
+    call gdk_pixbuf_loader_get_pixbuf() to fetch the partially-loaded pixbuf.
+  </para>
 
 <!-- ##### SIGNAL GdkPixbufLoader::area-updated ##### -->
   <para>
@@ -142,13 +153,7 @@ Application-driven progressive image loading.
     areas of an image that is being loaded.
   </para>
 
-@gdkpixbufloader: the object which received the signal.
-@arg1: 
-@arg2: 
-@arg3: 
-@arg4: 
-<!-- # Unused Parameters # -->
-@loader: Loader which emitted the signal.
+@gdkpixbufloader: Loader which emitted the signal.
 @x: X offset of upper-left corner of the updated area.
 @y: Y offset of upper-left corner of the updated area.
 @width: Width of updated area.
@@ -163,8 +168,6 @@ Application-driven progressive image loading.
   </para>
 
 @gdkpixbufloader: the object which received the signal.
-<!-- # Unused Parameters # -->
-@loader: Loader which emitted the signal.
 
 <!--
 Local variables:
@@ -173,3 +176,4 @@ sgml-parent-document: ("../gdk-pixbuf.sgml" "book" "refsect2" "")
 End:
 -->
 
+
diff --git a/docs/reference/gdk-pixbuf/tmpl/module_interface.sgml b/docs/reference/gdk-pixbuf/tmpl/module_interface.sgml
index 028041b871..5dd76877c5 100644
--- a/docs/reference/gdk-pixbuf/tmpl/module_interface.sgml
+++ b/docs/reference/gdk-pixbuf/tmpl/module_interface.sgml
@@ -23,6 +23,24 @@ Defines the type of the function used to set the vtable of a
 @module: a #GdkPixbufModule.
 
 
+<!-- ##### USER_FUNCTION ModuleSizeFunc ##### -->
+<para>
+Defines the type of the function that gets called once the size 
+of the loaded image is known is done.
+</para>
+<para>
+The function is expected to set @width and @height to the desired
+size to which the image should be scaled. If a module has no efficient 
+way to achieve the desired scaling during the loading of the image, it may
+either ignore the size request, or only approximate it -- the loader will
+then perform the required scaling on the completely loaded image. 
+</para>
+
+@width: pointer to a location containing the current image width
+@height: pointer to a location containing the current image height
+@user_data: the loader.
+
+
 <!-- ##### USER_FUNCTION ModulePreparedNotifyFunc ##### -->
 <para>
 Defines the type of the function that gets called once the initial 
diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index f72862b77d..b0d6ab4b4b 100644
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,34 @@
+2002-07-07  Matthias Clasen  <maclas@gmx.de>
+
+	Load-at-size functionality  (#53726): 
+	
+	* gdk-pixbuf-io.h (ModuleSizeFunc): New. 
+	(_GdkPixbufModule): Prepend a ModuleSizeFunc to the 
+	begin_load arguments. Adjust all modules.
+	* gdk-pixbuf-loader.c (struct GdkPixbufLoaderPrivate): Add
+	fields width, height, size_fixed, need_scale.
+	(gdk_pixbuf_loader_class_init): Add size_prepared signal.
+	(gdk_pixbuf_loader_set_size): New function.
+	(gdk_pixbuf_loader_size_func): ModuleSizeFunc which gets
+	passed to the module, emits size_prepared.
+	(gdk_pixbuf_loader_prepare): Call gdk_pixbuf_loader_size_func
+	if necessary, only emit area_prepared if no separate scaling
+	is required.
+	(gdk_pixbuf_loader_update): Only emit area_updated if no 
+	separate scaling is required.
+	(gdk_pixbuf_loader_load_module): Add size_func as first argument.
+	(gdk_pixbuf_loader_close): If necessary scale the image
+	to the desired size and emit area_prepared and area_updated.
+	* gdk-pixbuf-loader.h (struct _GdkPixbufLoaderClass): Add
+	size_prepared signal.
+	(gdk_pixbuf_loader_set_size) New API.
+	* gdk-pixbuf-marshal.list: Add VOID:INT,INT.
+	* io-jpeg.c: User cinfo->output_width/height instead of 
+	cinfo->image_width/height throughout when adressing the pixbuf.
+	(gdk_pixbuf__jpeg_image_load_increment): Call size_func, and
+	find the nearest possible output size which libjpeg can produce
+	that is still larger than the desired size.
+	
 2002-07-06  Matthias Clasen  <maclas@gmx.de>
 
 	* io-tiff.c (tiff_set_error): Handle global_error == NULL
diff --git a/gdk-pixbuf/gdk-pixbuf-io.h b/gdk-pixbuf/gdk-pixbuf-io.h
index 15e9de0a0f..8cf233fe26 100644
--- a/gdk-pixbuf/gdk-pixbuf-io.h
+++ b/gdk-pixbuf/gdk-pixbuf-io.h
@@ -37,6 +37,10 @@ G_BEGIN_DECLS
 
 
 
+typedef void (* ModuleSizeFunc)           (gint *width, 
+				           gint *height, 
+				           gpointer user_data);
+
 typedef void (* ModulePreparedNotifyFunc) (GdkPixbuf          *pixbuf,
                                            GdkPixbufAnimation *anim,
                                            gpointer            user_data);
@@ -58,7 +62,8 @@ struct _GdkPixbufModule {
 
         /* Incremental loading */
 
-        gpointer (* begin_load)     (ModulePreparedNotifyFunc prepare_func,
+        gpointer (* begin_load)     (ModuleSizeFunc size_func,
+                                     ModulePreparedNotifyFunc prepare_func,
                                      ModuleUpdatedNotifyFunc update_func,
                                      gpointer user_data,
                                      GError **error);
diff --git a/gdk-pixbuf/gdk-pixbuf-loader.c b/gdk-pixbuf/gdk-pixbuf-loader.c
index 52b1f112a6..bcb7382e32 100644
--- a/gdk-pixbuf/gdk-pixbuf-loader.c
+++ b/gdk-pixbuf/gdk-pixbuf-loader.c
@@ -31,8 +31,9 @@
 #include "gdk-pixbuf-marshal.h"
 
 enum {
-  AREA_UPDATED,
+  SIZE_PREPARED,
   AREA_PREPARED,
+  AREA_UPDATED,
   CLOSED,
   LAST_SIGNAL
 };
@@ -58,6 +59,10 @@ typedef struct
   gint header_buf_offset;
   GdkPixbufModule *image_module;
   gpointer context;
+  gint width;
+  gint height;
+  gboolean size_fixed;
+  gboolean needs_scale;
 } GdkPixbufLoaderPrivate;
 
 
@@ -109,6 +114,17 @@ gdk_pixbuf_loader_class_init (GdkPixbufLoaderClass *class)
   
   object_class->finalize = gdk_pixbuf_loader_finalize;
 
+  pixbuf_loader_signals[SIZE_PREPARED] =
+    g_signal_new ("size_prepared",
+                  G_TYPE_FROM_CLASS (object_class),
+                  G_SIGNAL_RUN_LAST,
+                  G_STRUCT_OFFSET (GdkPixbufLoaderClass, size_prepared),
+                  NULL, NULL,
+                  gdk_pixbuf_marshal_VOID__INT_INT,
+                  G_TYPE_NONE, 2, 
+		  G_TYPE_INT,
+		  G_TYPE_INT);
+  
   pixbuf_loader_signals[AREA_PREPARED] =
     g_signal_new ("area_prepared",
                   G_TYPE_FROM_CLASS (object_class),
@@ -170,14 +186,73 @@ gdk_pixbuf_loader_finalize (GObject *object)
   G_OBJECT_CLASS (parent_class)->finalize (object);
 }
 
+/**
+ * gdk_pixbuf_loader_set_size:
+ * @loader: A pixbuf loader.
+ * @width: The desired width of the image being loaded.
+ * @height: The desired height of the image being loaded.
+ *
+ * Causes the image to be scaled while it is loaded. The desired
+ * image size can be determined relative to the original size of
+ * the image by calling gdk_pixbuf_loader_set_size() from a
+ * signal handler for the ::size_prepared signal.
+ *
+ * Attempts to set the desired image size  are ignored after the 
+ * emission of the ::size_prepared signal.
+ */
+void 
+gdk_pixbuf_loader_set_size (GdkPixbufLoader *loader,
+			    gint             width,
+			    gint             height)
+{
+  GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
+  g_return_if_fail (width > 0 && height > 0);
+
+  if (!priv->size_fixed) {
+    priv->width = width;
+    priv->height = height;
+  }
+}
+
+static void
+gdk_pixbuf_loader_size_func (gint *width, gint *height, gpointer loader)
+{
+  GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
+
+  /* allow calling gdk_pixbuf_loader_set_size() before the signal */
+  if (priv->width == 0 && priv->height == 0) {
+    priv->width = *width;
+    priv->height = *height;
+  }
+
+  g_signal_emit (loader, pixbuf_loader_signals[SIZE_PREPARED], 0, *width, *height);
+  priv->size_fixed = TRUE;
+
+  *width = priv->width;
+  *height = priv->height;
+}
+
 static void
 gdk_pixbuf_loader_prepare (GdkPixbuf          *pixbuf,
                            GdkPixbufAnimation *anim,
 			   gpointer            loader)
 {
-  GdkPixbufLoaderPrivate *priv = NULL;
-  
-  priv = GDK_PIXBUF_LOADER (loader)->priv;
+  GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
+  g_return_if_fail (pixbuf != NULL);
+
+  if (!priv->size_fixed) {
+    /* Defend against lazy loaders which don't call size_func */
+    gint width = gdk_pixbuf_get_width (pixbuf);
+    gint height = gdk_pixbuf_get_height (pixbuf);
+
+    gdk_pixbuf_loader_size_func (&width, &height, loader);
+  }
+
+  priv->needs_scale = FALSE;
+  if (priv->width > 0 && priv->height > 0 &&
+      (priv->width != gdk_pixbuf_get_width (pixbuf) ||
+       priv->height != gdk_pixbuf_get_height (pixbuf)))
+    priv->needs_scale = TRUE;
 
   if (anim)
     g_object_ref (anim);
@@ -186,7 +261,8 @@ gdk_pixbuf_loader_prepare (GdkPixbuf          *pixbuf,
   
   priv->animation = anim;
   
-  g_signal_emit (loader, pixbuf_loader_signals[AREA_PREPARED], 0);
+  if (!priv->needs_scale)
+    g_signal_emit (loader, pixbuf_loader_signals[AREA_PREPARED], 0);
 }
 
 static void
@@ -197,17 +273,16 @@ gdk_pixbuf_loader_update (GdkPixbuf *pixbuf,
 			  gint       height,
 			  gpointer   loader)
 {
-  GdkPixbufLoaderPrivate *priv = NULL;
-  
-  priv = GDK_PIXBUF_LOADER (loader)->priv;
-  
-  g_signal_emit (loader,
-                 pixbuf_loader_signals[AREA_UPDATED],
-                 0,
-                 x, y,
-                 /* sanity check in here.  Defend against an errant loader */
-                 MIN (width, gdk_pixbuf_animation_get_width (priv->animation)),
-                 MIN (height, gdk_pixbuf_animation_get_height (priv->animation)));
+  GdkPixbufLoaderPrivate *priv = GDK_PIXBUF_LOADER (loader)->priv;
+  
+  if (!priv->needs_scale)
+    g_signal_emit (loader,
+		   pixbuf_loader_signals[AREA_UPDATED],
+		   0,
+		   x, y,
+		   /* sanity check in here.  Defend against an errant loader */
+		   MIN (width, gdk_pixbuf_animation_get_width (priv->animation)),
+		   MIN (height, gdk_pixbuf_animation_get_height (priv->animation)));
 }
 
 static gint
@@ -253,10 +328,11 @@ gdk_pixbuf_loader_load_module (GdkPixbufLoader *loader,
       return 0;
     }
 
-  priv->context = priv->image_module->begin_load (gdk_pixbuf_loader_prepare,
-						  gdk_pixbuf_loader_update,
-						  loader,
-                                                  error);
+    priv->context = priv->image_module->begin_load (gdk_pixbuf_loader_size_func,
+						    gdk_pixbuf_loader_prepare,
+						    gdk_pixbuf_loader_update,
+						    loader,
+						    error);
   
   if (priv->context == NULL)
     {
@@ -536,12 +612,33 @@ gdk_pixbuf_loader_close (GdkPixbufLoader *loader,
 	  retval = FALSE;
 	}
     }  
+
   if (priv->image_module && priv->image_module->stop_load && priv->context) {
     if (!priv->image_module->stop_load (priv->context, error))
       retval = FALSE;
   }
   
   priv->closed = TRUE;
+
+  if (priv->needs_scale) {
+    GdkPixbuf *tmp, *pixbuf;
+
+    tmp = gdk_pixbuf_animation_get_static_image (priv->animation);
+    g_object_ref (tmp);
+    pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, tmp->has_alpha, 8, priv->width, priv->height);
+    g_object_unref (priv->animation);
+    priv->animation = gdk_pixbuf_non_anim_new (pixbuf);
+    g_signal_emit (loader, pixbuf_loader_signals[AREA_PREPARED], 0);
+    gdk_pixbuf_scale (tmp, pixbuf, 0, 0, priv->width, priv->height, 0, 0,
+		      (double) priv->width / tmp->width,
+		      (double) priv->height / tmp->height,
+		      GDK_INTERP_BILINEAR); 
+    g_object_unref (tmp);
+
+    g_signal_emit (loader, pixbuf_loader_signals[AREA_UPDATED], 0, 
+		   0, 0, priv->width, priv->height);
+  }
+
   
   g_signal_emit (loader, pixbuf_loader_signals[CLOSED], 0);
 
@@ -549,3 +646,7 @@ gdk_pixbuf_loader_close (GdkPixbufLoader *loader,
 }
 
 
+
+
+
+
diff --git a/gdk-pixbuf/gdk-pixbuf-loader.h b/gdk-pixbuf/gdk-pixbuf-loader.h
index bacaf9d38c..030d446fa1 100644
--- a/gdk-pixbuf/gdk-pixbuf-loader.h
+++ b/gdk-pixbuf/gdk-pixbuf-loader.h
@@ -50,6 +50,10 @@ struct _GdkPixbufLoaderClass
 {
   GObjectClass parent_class;
 
+  void (*size_prepared)      (GdkPixbufLoader *loader, 
+			      int              width,
+			      int              height);
+
   void (*area_prepared)      (GdkPixbufLoader *loader);
 
   /* Last known frame needs a redraw for x, y, width, height */
@@ -62,11 +66,13 @@ struct _GdkPixbufLoaderClass
   void (*closed)             (GdkPixbufLoader *loader);
 };
 
-
 GType                gdk_pixbuf_loader_get_type      (void) G_GNUC_CONST;
 GdkPixbufLoader *    gdk_pixbuf_loader_new           (void);
 GdkPixbufLoader *    gdk_pixbuf_loader_new_with_type (const char *image_type,
                                                       GError    **error);
+void                 gdk_pixbuf_loader_set_size (GdkPixbufLoader  *loader,
+                                                 int               width,
+						 int               height);
 gboolean             gdk_pixbuf_loader_write         (GdkPixbufLoader *loader,
 						      const guchar    *buf,
 						      gsize            count,
@@ -80,3 +86,5 @@ gboolean             gdk_pixbuf_loader_close         (GdkPixbufLoader *loader,
 G_END_DECLS
 
 #endif
+
+
diff --git a/gdk-pixbuf/gdk-pixbuf-marshal.list b/gdk-pixbuf/gdk-pixbuf-marshal.list
index db100651bb..9e63f91c4f 100644
--- a/gdk-pixbuf/gdk-pixbuf-marshal.list
+++ b/gdk-pixbuf/gdk-pixbuf-marshal.list
@@ -25,3 +25,4 @@
 VOID:VOID
 VOID:INT,INT,INT,INT
 VOID:POINTER
+VOID:INT,INT
diff --git a/gdk-pixbuf/io-bmp.c b/gdk-pixbuf/io-bmp.c
index 8b0e3c07df..83df835f3d 100644
--- a/gdk-pixbuf/io-bmp.c
+++ b/gdk-pixbuf/io-bmp.c
@@ -181,7 +181,8 @@ struct bmp_progressive_state {
 };
 
 static gpointer
-gdk_pixbuf__bmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__bmp_image_begin_load(ModuleSizeFunc size_func,
+                                 ModulePreparedNotifyFunc prepared_func,
 				 ModuleUpdatedNotifyFunc updated_func,
                                  gpointer user_data,
                                  GError **error);
@@ -205,7 +206,7 @@ static GdkPixbuf *gdk_pixbuf__bmp_image_load(FILE * f, GError **error)
 	GdkPixbuf *pb;
 
 	State =
-	    gdk_pixbuf__bmp_image_begin_load(NULL, NULL, NULL,
+	    gdk_pixbuf__bmp_image_begin_load(NULL, NULL, NULL, NULL,
                                              error);
 
         if (State == NULL)
@@ -512,7 +513,8 @@ decode_bitmasks (guchar *buf,
  */
 
 static gpointer
-gdk_pixbuf__bmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__bmp_image_begin_load(ModuleSizeFunc size_func,
+                                 ModulePreparedNotifyFunc prepared_func,
 				 ModuleUpdatedNotifyFunc updated_func,
                                  gpointer user_data,
                                  GError **error)
diff --git a/gdk-pixbuf/io-gif.c b/gdk-pixbuf/io-gif.c
index 09c843e840..b85e2ea958 100644
--- a/gdk-pixbuf/io-gif.c
+++ b/gdk-pixbuf/io-gif.c
@@ -1396,7 +1396,8 @@ gdk_pixbuf__gif_image_load (FILE *file, GError **error)
 }
 
 static gpointer
-gdk_pixbuf__gif_image_begin_load (ModulePreparedNotifyFunc prepare_func,
+gdk_pixbuf__gif_image_begin_load (ModuleSizeFunc size_func,
+                                  ModulePreparedNotifyFunc prepare_func,
 				  ModuleUpdatedNotifyFunc update_func,
 				  gpointer user_data,
                                   GError **error)
diff --git a/gdk-pixbuf/io-ico.c b/gdk-pixbuf/io-ico.c
index bac4d8e907..1a1de441e4 100644
--- a/gdk-pixbuf/io-ico.c
+++ b/gdk-pixbuf/io-ico.c
@@ -158,7 +158,8 @@ struct ico_progressive_state {
 };
 
 static gpointer
-gdk_pixbuf__ico_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__ico_image_begin_load(ModuleSizeFunc size_func,
+                                 ModulePreparedNotifyFunc prepared_func,
 				 ModuleUpdatedNotifyFunc updated_func,
 				 gpointer user_data,
                                  GError **error);
@@ -193,7 +194,7 @@ gdk_pixbuf__ico_image_load(FILE * f, GError **error)
 
 	GdkPixbuf *pb;
 
-	State = gdk_pixbuf__ico_image_begin_load(NULL, NULL, NULL, error);
+	State = gdk_pixbuf__ico_image_begin_load(NULL, NULL, NULL, NULL, error);
 
         if (State == NULL)
 		return NULL;
@@ -478,7 +479,8 @@ static void DecodeHeader(guchar *Data, gint Bytes,
  */
 
 static gpointer
-gdk_pixbuf__ico_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__ico_image_begin_load(ModuleSizeFunc size_func,
+                                 ModulePreparedNotifyFunc prepared_func,
 				 ModuleUpdatedNotifyFunc updated_func,
 				 gpointer user_data,
                                  GError **error)
diff --git a/gdk-pixbuf/io-jpeg.c b/gdk-pixbuf/io-jpeg.c
index 0081402e83..9641099422 100644
--- a/gdk-pixbuf/io-jpeg.c
+++ b/gdk-pixbuf/io-jpeg.c
@@ -1,3 +1,4 @@
+/* -*- mode: C; c-file-style: "linux" -*- */
 /* GdkPixbuf library - JPEG image loader
  *
  * Copyright (C) 1999 Michael Zucchi
@@ -50,7 +51,7 @@ typedef struct {
 
 	JOCTET buffer[JPEG_PROG_BUF_SIZE];              /* start of buffer */
 	long  skip_next;              /* number of bytes to skip next read */
-
+	
 } my_source_mgr;
 
 typedef my_source_mgr * my_src_ptr;
@@ -64,6 +65,7 @@ struct error_handler_data {
 
 /* progressive loader context */
 typedef struct {
+        ModuleSizeFunc           size_func;
 	ModuleUpdatedNotifyFunc  updated_func;
 	ModulePreparedNotifyFunc prepared_func;
 	gpointer                 user_data;
@@ -80,7 +82,8 @@ typedef struct {
 } JpegProgContext;
 
 static GdkPixbuf *gdk_pixbuf__jpeg_image_load (FILE *f, GError **error);
-static gpointer gdk_pixbuf__jpeg_image_begin_load (ModulePreparedNotifyFunc func, 
+static gpointer gdk_pixbuf__jpeg_image_begin_load (ModuleSizeFunc           func0,
+                                                   ModulePreparedNotifyFunc func1, 
                                                    ModuleUpdatedNotifyFunc func2,
                                                    gpointer user_data,
                                                    GError **error);
@@ -140,7 +143,7 @@ explode_gray_into_buf (struct jpeg_decompress_struct *cinfo,
 	/* Expand grey->colour.  Expand from the end of the
 	 * memory down, so we can use the same buffer.
 	 */
-	w = cinfo->image_width;
+	w = cinfo->output_width;
 	for (i = cinfo->rec_outbuf_height - 1; i >= 0; i--) {
 		guchar *from, *to;
 		
@@ -171,7 +174,7 @@ convert_cmyk_to_rgb (struct jpeg_decompress_struct *cinfo,
 		guchar *p;
 		
 		p = lines[i];
-		for (j = 0; j < cinfo->image_width; j++) {
+		for (j = 0; j < cinfo->output_width; j++) {
 			int c, m, y, k;
 			c = p[0];
 			m = p[1];
@@ -446,8 +449,9 @@ skip_input_data (j_decompress_ptr cinfo, long num_bytes)
  */
 
 gpointer
-gdk_pixbuf__jpeg_image_begin_load (ModulePreparedNotifyFunc prepared_func, 
-				   ModuleUpdatedNotifyFunc  updated_func,
+gdk_pixbuf__jpeg_image_begin_load (ModuleSizeFunc size_func,
+				   ModulePreparedNotifyFunc prepared_func, 
+				   ModuleUpdatedNotifyFunc updated_func,
 				   gpointer user_data,
                                    GError **error)
 {
@@ -455,6 +459,7 @@ gdk_pixbuf__jpeg_image_begin_load (ModulePreparedNotifyFunc prepared_func,
 	my_source_mgr   *src;
 
 	context = g_new0 (JpegProgContext, 1);
+	context->size_func = size_func;
 	context->prepared_func = prepared_func;
 	context->updated_func  = updated_func;
 	context->user_data = user_data;
@@ -469,11 +474,11 @@ gdk_pixbuf__jpeg_image_begin_load (ModulePreparedNotifyFunc prepared_func,
 
 	context->cinfo.src = (struct jpeg_source_mgr *) g_try_malloc (sizeof (my_source_mgr));
 	if (!context->cinfo.src) {
-	  g_set_error (error,
-		       GDK_PIXBUF_ERROR,
-		       GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
-		       _("Couldn't allocate memory for loading JPEG file"));
-	  return NULL;
+		g_set_error (error,
+			     GDK_PIXBUF_ERROR,
+			     GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
+			     _("Couldn't allocate memory for loading JPEG file"));
+		return NULL;
 	}
 	memset (context->cinfo.src, 0, sizeof (my_source_mgr));
        
@@ -509,14 +514,14 @@ gdk_pixbuf__jpeg_image_stop_load (gpointer data, GError **error)
 	JpegProgContext *context = (JpegProgContext *) data;
 
 	g_return_val_if_fail (context != NULL, TRUE);
-
+	
         /* FIXME this thing needs to report errors if
          * we have unused image data
          */
         
 	if (context->pixbuf)
 		g_object_unref (context->pixbuf);
-
+	
 	/* if we have an error? */
 	if (sigsetjmp (context->jerr.setjmp_buffer, 1)) {
 		jpeg_destroy_decompress (&context->cinfo);
@@ -559,6 +564,7 @@ gdk_pixbuf__jpeg_image_load_increment (gpointer data,
 	guint       spinguard;
 	gboolean    first;
 	const guchar *bufhd;
+	gint        width, height;
 
 	g_return_val_if_fail (context != NULL, FALSE);
 	g_return_val_if_fail (buf != NULL, FALSE);
@@ -569,10 +575,6 @@ gdk_pixbuf__jpeg_image_load_increment (gpointer data,
 
         context->jerr.error = error;
         
-	/* XXXXXXX (drmike) - loop(s) below need to be recoded now I
-         *                    have a grasp of what the flow needs to be!
-         */
-
 	/* check for fatal error */
 	if (sigsetjmp (context->jerr.setjmp_buffer, 1)) {
 		return FALSE;
@@ -636,29 +638,32 @@ gdk_pixbuf__jpeg_image_load_increment (gpointer data,
 		/* try to load jpeg header */
 		if (!context->got_header) {
 			int rc;
-
+			
 			rc = jpeg_read_header (cinfo, TRUE);
 			context->src_initialized = TRUE;
-
+			
 			if (rc == JPEG_SUSPENDED)
 				continue;
-
+			
 			context->got_header = TRUE;
-
-		} else if (!context->did_prescan) {
-			int rc;
 			
-			/* start decompression */
-			cinfo->buffered_image = TRUE;
-			rc = jpeg_start_decompress (cinfo);
-			cinfo->do_fancy_upsampling = FALSE;
-			cinfo->do_block_smoothing = FALSE;
-
-			context->pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, 
-							 cinfo->output_components == 4 ? TRUE : FALSE,
-							 8, 
-							 cinfo->image_width,
-							 cinfo->image_height);
+			width = cinfo->image_width;
+			height = cinfo->image_height;
+			(* context->size_func) (&width, &height, context->user_data);
+			for (cinfo->scale_denom = 2; cinfo->scale_denom <= 8; cinfo->scale_denom *= 2) {
+				jpeg_calc_output_dimensions (cinfo);
+				if (cinfo->output_width < width || cinfo->output_height < height) {
+					cinfo->scale_denom /= 2;
+					break;
+				}
+			}
+			jpeg_calc_output_dimensions (cinfo);
+			
+			context->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, 
+							  cinfo->output_components == 4 ? TRUE : FALSE,
+							  8, 
+							  cinfo->output_width,
+							  cinfo->output_height);
 
 			if (context->pixbuf == NULL) {
                                 g_set_error (error,
@@ -667,16 +672,24 @@ gdk_pixbuf__jpeg_image_load_increment (gpointer data,
                                              _("Couldn't allocate memory for loading JPEG file"));
                                 return FALSE;
 			}
-
+			
 			/* Use pixbuf buffer to store decompressed data */
 			context->dptr = context->pixbuf->pixels;
-
+			
 			/* Notify the client that we are ready to go */
 			(* context->prepared_func) (context->pixbuf,
                                                     NULL,
 						    context->user_data);
-
 			
+		} else if (!context->did_prescan) {
+			int rc;			
+			
+			/* start decompression */
+			cinfo->buffered_image = TRUE;
+			rc = jpeg_start_decompress (cinfo);
+			cinfo->do_fancy_upsampling = FALSE;
+			cinfo->do_block_smoothing = FALSE;
+
 			if (rc == JPEG_SUSPENDED)
 				continue;
 
diff --git a/gdk-pixbuf/io-png.c b/gdk-pixbuf/io-png.c
index 9081096e7d..dc886f8322 100644
--- a/gdk-pixbuf/io-png.c
+++ b/gdk-pixbuf/io-png.c
@@ -386,7 +386,8 @@ struct _LoadContext {
 };
 
 static gpointer
-gdk_pixbuf__png_image_begin_load (ModulePreparedNotifyFunc prepare_func,
+gdk_pixbuf__png_image_begin_load (ModuleSizeFunc size_func,
+                                  ModulePreparedNotifyFunc prepare_func,
 				  ModuleUpdatedNotifyFunc update_func,
 				  gpointer user_data,
                                   GError **error)
diff --git a/gdk-pixbuf/io-pnm.c b/gdk-pixbuf/io-pnm.c
index 797f937178..c137191464 100644
--- a/gdk-pixbuf/io-pnm.c
+++ b/gdk-pixbuf/io-pnm.c
@@ -81,7 +81,8 @@ typedef struct {
 } PnmLoaderContext;
 
 static GdkPixbuf   *gdk_pixbuf__pnm_image_load          (FILE *f, GError **error);
-static gpointer    gdk_pixbuf__pnm_image_begin_load     (ModulePreparedNotifyFunc func, 
+static gpointer    gdk_pixbuf__pnm_image_begin_load     (ModuleSizeFunc size_func, 
+                                                         ModulePreparedNotifyFunc func, 
 							 ModuleUpdatedNotifyFunc func2,
 							 gpointer user_data,
 							 GError **error);
@@ -803,7 +804,8 @@ gdk_pixbuf__pnm_image_load (FILE *f, GError **error)
  */
 
 static gpointer
-gdk_pixbuf__pnm_image_begin_load (ModulePreparedNotifyFunc prepared_func, 
+gdk_pixbuf__pnm_image_begin_load (ModuleSizeFunc size_func, 
+                                  ModulePreparedNotifyFunc prepared_func, 
 				  ModuleUpdatedNotifyFunc  updated_func,
 				  gpointer user_data,
 				  GError **error)
diff --git a/gdk-pixbuf/io-ras.c b/gdk-pixbuf/io-ras.c
index cc39e6a28e..32bc35abf9 100644
--- a/gdk-pixbuf/io-ras.c
+++ b/gdk-pixbuf/io-ras.c
@@ -94,7 +94,8 @@ struct ras_progressive_state {
 };
 
 static gpointer
-gdk_pixbuf__ras_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__ras_image_begin_load(ModuleSizeFunc size_func,
+                                 ModulePreparedNotifyFunc prepared_func,
 				 ModuleUpdatedNotifyFunc updated_func,
 				 gpointer user_data,
                                  GError **error);
@@ -114,7 +115,7 @@ static GdkPixbuf *gdk_pixbuf__ras_image_load(FILE * f, GError **error)
 	
 	GdkPixbuf *pb;
 	
-	State = gdk_pixbuf__ras_image_begin_load(NULL, NULL, NULL, error);
+	State = gdk_pixbuf__ras_image_begin_load(NULL, NULL, NULL, NULL, error);
 	
 	membuf = g_malloc(4096);
 	
@@ -251,7 +252,8 @@ static gboolean RAS2State(struct rasterfile *RAS,
  */
 
 static gpointer
-gdk_pixbuf__ras_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__ras_image_begin_load(ModuleSizeFunc size_func, 
+                                 ModulePreparedNotifyFunc prepared_func,
 				 ModuleUpdatedNotifyFunc updated_func,
 				 gpointer user_data,
                                  GError **error)
diff --git a/gdk-pixbuf/io-tga.c b/gdk-pixbuf/io-tga.c
index 87a7ea659a..08259d8323 100644
--- a/gdk-pixbuf/io-tga.c
+++ b/gdk-pixbuf/io-tga.c
@@ -801,7 +801,8 @@ static gboolean try_preload(TGAContext *ctx, GError **err)
 	return TRUE;
 }
 
-static gpointer gdk_pixbuf__tga_begin_load(ModulePreparedNotifyFunc f1,
+static gpointer gdk_pixbuf__tga_begin_load(ModuleSizeFunc f0,
+                                           ModulePreparedNotifyFunc f1,
 					   ModuleUpdatedNotifyFunc f2,
 					   gpointer udata, GError **err)
 {
diff --git a/gdk-pixbuf/io-tiff.c b/gdk-pixbuf/io-tiff.c
index deae12bd77..d376147648 100644
--- a/gdk-pixbuf/io-tiff.c
+++ b/gdk-pixbuf/io-tiff.c
@@ -361,7 +361,8 @@ gdk_pixbuf__tiff_image_load (FILE *f, GError **error)
 /* Progressive loader */
 
 static gpointer
-gdk_pixbuf__tiff_image_begin_load (ModulePreparedNotifyFunc prepare_func,
+gdk_pixbuf__tiff_image_begin_load (ModuleSizeFunc size_func,
+                                   ModulePreparedNotifyFunc prepare_func,
 				   ModuleUpdatedNotifyFunc update_func,
 				   gpointer user_data,
                                    GError **error)
diff --git a/gdk-pixbuf/io-wbmp.c b/gdk-pixbuf/io-wbmp.c
index bfbfb4c36e..14bb115365 100644
--- a/gdk-pixbuf/io-wbmp.c
+++ b/gdk-pixbuf/io-wbmp.c
@@ -63,7 +63,8 @@ struct wbmp_progressive_state {
 };
 
 static gpointer
-gdk_pixbuf__wbmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__wbmp_image_begin_load(ModuleSizeFunc size_func, 
+                                  ModulePreparedNotifyFunc prepared_func,
 				  ModuleUpdatedNotifyFunc updated_func,
                                   gpointer user_data,
                                   GError **error);
@@ -85,7 +86,7 @@ static GdkPixbuf *gdk_pixbuf__wbmp_image_load(FILE * f, GError **error)
 
 	GdkPixbuf *pb;
 
-	State = gdk_pixbuf__wbmp_image_begin_load(NULL, NULL, NULL,
+	State = gdk_pixbuf__wbmp_image_begin_load(NULL, NULL, NULL, NULL,
                                                   error);
 
         if (State == NULL)
@@ -116,7 +117,8 @@ static GdkPixbuf *gdk_pixbuf__wbmp_image_load(FILE * f, GError **error)
  */
 
 static gpointer
-gdk_pixbuf__wbmp_image_begin_load(ModulePreparedNotifyFunc prepared_func,
+gdk_pixbuf__wbmp_image_begin_load(ModuleSizeFunc size_func, 
+                                  ModulePreparedNotifyFunc prepared_func,
                                   ModuleUpdatedNotifyFunc updated_func,
                                   gpointer user_data,
                                   GError **error)
diff --git a/gdk-pixbuf/io-xbm.c b/gdk-pixbuf/io-xbm.c
index 3ef06bb2a8..71e6e40393 100644
--- a/gdk-pixbuf/io-xbm.c
+++ b/gdk-pixbuf/io-xbm.c
@@ -353,7 +353,8 @@ gdk_pixbuf__xbm_image_load (FILE *f, GError **error)
  */
 
 static gpointer
-gdk_pixbuf__xbm_image_begin_load (ModulePreparedNotifyFunc prepare_func,
+gdk_pixbuf__xbm_image_begin_load (ModuleSizeFunc size_func,
+                                  ModulePreparedNotifyFunc prepare_func,
 				  ModuleUpdatedNotifyFunc update_func,
 				  gpointer user_data,
 				  GError **error)
diff --git a/gdk-pixbuf/io-xpm.c b/gdk-pixbuf/io-xpm.c
index 6f47766768..ee9d44e385 100644
--- a/gdk-pixbuf/io-xpm.c
+++ b/gdk-pixbuf/io-xpm.c
@@ -1416,7 +1416,8 @@ struct _XPMContext
  * in the future.
  */
 static gpointer
-gdk_pixbuf__xpm_image_begin_load (ModulePreparedNotifyFunc prepare_func,
+gdk_pixbuf__xpm_image_begin_load (ModuleSizeFunc size_func,
+                                  ModulePreparedNotifyFunc prepare_func,
                                   ModuleUpdatedNotifyFunc update_func,
                                   gpointer user_data,
                                   GError **error)