Use a dynamic pixbuf cache size based on document page size

Instead of using a static number of pages to cache, we use a size in
bytes, and the number of pages that will be cached depends on the
current zoom level. It allows us caching more pages for lower scale
factors and increase zoom level by caching fewer pages. See bug #303365.

1 files changed, 38 insertions, 11 deletions

diff --git a/shell/ev-window.c b/shell/ev-window.c
index d4057b1..d737356 100644
--- a/shell/ev-window.c
+++ b/shell/ev-window.c
@@ -34,6 +34,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <math.h>
 
 #include <glib/gstdio.h>
 #include <glib/gi18n.h>
@@ -243,7 +244,7 @@ struct _EvWindowPrivate {
 #define EV_TOOLBARS_FILENAME "evince-toolbar.xml"
 
 #define MIN_SCALE 0.05409
-#define MAX_SCALE 4.0
+#define PAGE_CACHE_SIZE 52428800 /* 50MB */
 
 #define MAX_RECENT_ITEM_LEN (40)
 
@@ -325,6 +326,7 @@ static void     ev_window_load_file_remote              (EvWindow         *ev_wi
 static void     ev_window_media_player_key_pressed      (EvWindow         *window,
 							 const gchar      *key,
 							 gpointer          user_data);
+static void     ev_window_update_max_min_scale          (EvWindow         *window);
 
 static guint ev_window_n_copies = 0;
 
@@ -1225,7 +1227,7 @@ ev_window_setup_document (EvWindow *ev_window)
 	GtkAction *action;
 
 	ev_window->priv->setup_document_idle = 0;
-	
+
 	ev_window_refresh_window_thumbnail (ev_window);
 
 	ev_window_set_page_mode (ev_window, PAGE_MODE_DOCUMENT);
@@ -1286,6 +1288,8 @@ ev_window_set_document (EvWindow *ev_window, EvDocument *document)
 		g_object_unref (ev_window->priv->document);
 	ev_window->priv->document = g_object_ref (document);
 
+	ev_window_update_max_min_scale (ev_window);
+
 	ev_window_set_message_area (ev_window, NULL);
 
 	if (ev_document_get_n_pages (document) <= 0) {
@@ -3732,22 +3736,46 @@ ev_window_setup_gtk_settings (EvWindow *window)
 }
 
 static void
+ev_window_update_max_min_scale (EvWindow *window)
+{
+	gdouble    dpi;
+	GtkAction *action;
+	gdouble    min_width, min_height;
+	gdouble    width, height;
+	gdouble    max_scale;
+	gint       rotation = ev_document_model_get_rotation (window->priv->model);
+
+	if (!window->priv->document)
+		return;
+
+	dpi = get_screen_dpi (window) / 72.0;
+
+	ev_document_get_min_page_size (window->priv->document, &min_width, &min_height);
+	width = (rotation == 0 || rotation == 180) ? min_width : min_height;
+	height = (rotation == 0 || rotation == 180) ? min_height : min_width;
+	max_scale = sqrt (PAGE_CACHE_SIZE / (width * dpi * 4 * height * dpi));
+
+	action = gtk_action_group_get_action (window->priv->action_group,
+					      ZOOM_CONTROL_ACTION);
+	ephy_zoom_action_set_max_zoom_level (EPHY_ZOOM_ACTION (action), max_scale * dpi);
+
+	ev_document_model_set_min_scale (window->priv->model, MIN_SCALE * dpi);
+	ev_document_model_set_max_scale (window->priv->model, max_scale * dpi);
+}
+
+static void
 ev_window_screen_changed (GtkWidget *widget,
 			  GdkScreen *old_screen)
 {
 	EvWindow *window = EV_WINDOW (widget);
-	EvWindowPrivate *priv = window->priv;
 	GdkScreen *screen;
-	gdouble dpi;
 
 	screen = gtk_widget_get_screen (widget);
 	if (screen == old_screen)
 		return;
 
 	ev_window_setup_gtk_settings (window);
-	dpi = get_screen_dpi (window);
-	ev_document_model_set_min_scale (priv->model, MIN_SCALE * dpi / 72.0);
-	ev_document_model_set_max_scale (priv->model, MAX_SCALE * dpi / 72.0);
+	ev_window_update_max_min_scale (window);
 
 	if (GTK_WIDGET_CLASS (ev_window_parent_class)->screen_changed) {
 		GTK_WIDGET_CLASS (ev_window_parent_class)->screen_changed (widget, old_screen);
@@ -4165,6 +4193,7 @@ ev_window_rotation_changed_cb (EvDocumentModel *model,
 		ev_metadata_set_int (window->priv->metadata, "rotation",
 				     rotation);
 
+	ev_window_update_max_min_scale (window);
 	ev_window_refresh_window_thumbnail (window);
 }
 
@@ -6130,7 +6159,6 @@ ev_window_init (EvWindow *ev_window)
 	EggToolbarsModel *toolbars_model;
 	GObject *mpkeys;
 	gchar *ui_path;
-	gdouble dpi;
 
 	g_signal_connect (ev_window, "configure_event",
 			  G_CALLBACK (window_configure_event_cb), NULL);
@@ -6316,10 +6344,9 @@ ev_window_init (EvWindow *ev_window)
 	gtk_widget_show (ev_window->priv->view_box);
 
 	ev_window->priv->view = ev_view_new ();
+	ev_view_set_page_cache_size (EV_VIEW (ev_window->priv->view), PAGE_CACHE_SIZE);
 	ev_view_set_model (EV_VIEW (ev_window->priv->view), ev_window->priv->model);
-	dpi = get_screen_dpi (ev_window);
-	ev_document_model_set_min_scale (ev_window->priv->model, MIN_SCALE * dpi / 72.0);
-	ev_document_model_set_max_scale (ev_window->priv->model, MAX_SCALE * dpi / 72.0);
+
 	ev_window->priv->password_view = ev_password_view_new (GTK_WINDOW (ev_window));
 	g_signal_connect_swapped (ev_window->priv->password_view,
 				  "unlock",