add parameters providing allocation width and height without scrollbars

* shell/ev-view.c (ev_view_best_fit, ev_view_fit_width): add
parameters providing allocation width and height without
scrollbars and width of a possible vertical scrollbar. With this
additional information the functions can work as
intended. Unfortunately they're not idempotent. We should
transform these commands to toggles. Fixes Bug #164976
Initial patch by Stephane Loeuillet, then heavily modified.

* shell/ev-view.h: update prototypes.

* shell/ev-window.c (ev_window_cmd_view_best_fit)
(ev_window_cmd_view_page_width): provide EvView fit functions with
all the information they need. Formulas to calculate this
information taken from GtkScrolledWindow.

3 files changed, 68 insertions, 13 deletions

diff --git a/shell/ev-view.c b/shell/ev-view.c
index 8fd8723..e3c81a0 100644
--- a/shell/ev-view.c
+++ b/shell/ev-view.c
@@ -1233,21 +1233,34 @@ ev_view_normal_size (EvView *view)
 	ev_view_zoom (view, 1.0, FALSE);
 }
 
+/* Unfortunately this is not idempotent (!) (numerical stability
+ * issues because width and height are rounded)
+ *
+ * One more reason to make this a toggle and not a command */
 void
-ev_view_best_fit (EvView *view)
+ev_view_best_fit (EvView *view, int allocation_width, int allocation_height)
 {
 	double scale;
+	int available_width, available_height;
 	int width, height;
 
 	width = height = 0;
+	/* This is the bad part. You could make it stable by doing
+	 * ev_document_set_scale 1.0. But at least with pdf this means
+	 * redrawing the whole page */
 	ev_document_get_page_size (view->document, -1, &width, &height);
 
+	LOG ("Best fit %d %d", allocation_width, allocation_height);
+
 	scale = 1.0;
 	if (width != 0 && height != 0) {
 		double scale_w, scale_h;
 
-		scale_w = (double)GTK_WIDGET (view)->allocation.width * view->scale / width;
-		scale_h = (double)GTK_WIDGET (view)->allocation.height * view->scale / height;
+		available_width = MAX (1, allocation_width - 2); /* 1 px border left and right */
+		available_height = MAX (1, allocation_height - 2); /* 1 px border above and below */
+
+		scale_w = (double)available_width * view->scale / (width + 0.5);
+		scale_h = (double)available_height * view->scale / (height + 0.5);
 
 		scale = (scale_w < scale_h) ? scale_w : scale_h;
 	}
@@ -1256,17 +1269,27 @@ ev_view_best_fit (EvView *view)
 }
 
 void
-ev_view_fit_width (EvView *view)
+ev_view_fit_width (EvView *view, int allocation_width, int allocation_height,
+		   int vsb_width)
 {
+	int available_width, available_height;
+	int width, height;
 	double scale = 1.0;
-	int width;
 
-	width = 0;
-	ev_document_get_page_size (view->document, -1, &width, NULL);
+	width = height = 0;
+	ev_document_get_page_size (view->document, -1, &width, &height);
 
 	scale = 1.0;
-	if (width != 0)
-		scale = (double)GTK_WIDGET (view)->allocation.width * view->scale / width;
+	if (width != 0) {
+		available_width = MAX (1, allocation_width - 2); /* 1px border */
+		available_height = MAX (1, allocation_height - 2); /* 1px border */
+
+		scale = (double)available_width * view->scale / (width + 0.5);
+
+		if ((height + 0.5) * scale / view->scale > available_height)
+			scale = ((double)(available_width - vsb_width) * view->scale /
+				 (width + 0.5));
+	}
 
 	ev_view_zoom (view, scale, FALSE);
 }
diff --git a/shell/ev-view.h b/shell/ev-view.h
index a72ed6b..f108f9f 100644
--- a/shell/ev-view.h
+++ b/shell/ev-view.h
@@ -58,8 +58,8 @@ int		ev_view_get_page	(EvView     *view);
 void		ev_view_zoom_in		(EvView     *view);
 void		ev_view_zoom_out	(EvView     *view);
 void		ev_view_normal_size	(EvView     *view);
-void		ev_view_best_fit	(EvView     *view);
-void		ev_view_fit_width	(EvView     *view);
+void		ev_view_best_fit	(EvView     *view, int width, int height);
+void		ev_view_fit_width	(EvView     *view, int width, int height, int vsb_width);
 
 /* Find */
 void            ev_view_find_next       (EvView     *view);
diff --git a/shell/ev-window.c b/shell/ev-window.c
index a1d74f6..547eaf0 100644
--- a/shell/ev-window.c
+++ b/shell/ev-window.c
@@ -1197,17 +1197,49 @@ ev_window_cmd_view_normal_size (GtkAction *action, EvWindow *ev_window)
 static void
 ev_window_cmd_view_best_fit (GtkAction *action, EvWindow *ev_window)
 {
+	EvWindowPrivate *priv = ev_window->priv;
+	int width, height;
+
         g_return_if_fail (EV_IS_WINDOW (ev_window));
 
-	ev_view_best_fit (EV_VIEW (ev_window->priv->view));
+	width = priv->scrolled_window->allocation.width;
+	height = priv->scrolled_window->allocation.height;
+
+	/* the scrolled window has a GTK_SHADOW_IN */
+	width -= 2 * priv->view->style->xthickness;
+	height -= 2 * priv->view->style->ythickness;
+
+	ev_view_best_fit (EV_VIEW (priv->view),
+			  MAX (1, width), MAX (1, height));
 }
 
 static void
 ev_window_cmd_view_page_width (GtkAction *action, EvWindow *ev_window)
 {
+	EvWindowPrivate *priv = ev_window->priv;
+	int width, height;
+	GtkRequisition vsb_requisition;
+	int scrollbar_spacing;
+
         g_return_if_fail (EV_IS_WINDOW (ev_window));
 
-	ev_view_fit_width (EV_VIEW (ev_window->priv->view));
+	width = priv->scrolled_window->allocation.width;
+	height = priv->scrolled_window->allocation.height;
+
+	/* the scrolled window has a GTK_SHADOW_IN */
+	width -= 2 * priv->view->style->xthickness;
+	height -= 2 * priv->view->style->ythickness;
+
+	gtk_widget_size_request (
+		GTK_SCROLLED_WINDOW (priv->scrolled_window)->vscrollbar,
+		&vsb_requisition);
+	gtk_widget_style_get (priv->scrolled_window,
+			      "scrollbar_spacing", &scrollbar_spacing,
+			      NULL);
+
+	ev_view_fit_width (EV_VIEW (ev_window->priv->view),
+			   width, height,
+			   vsb_requisition.width + scrollbar_spacing);
 }
 
 static void