From b5237680f28d585fecf1c6d23bc7ec044e623ae1 Mon Sep 17 00:00:00 2001
From: Sebastian Ramacher <sebastian+dev@ramacher.at>
Date: Sat, 27 Jul 2013 16:25:20 +0200
Subject: [PATCH] Don't store surface for invisible and uncached pages

Signed-off-by: Sebastian Ramacher <sebastian+dev@ramacher.at>
---
 callbacks.c   |  6 ++++++
 page-widget.c | 20 +++++++++++++++++---
 page-widget.h |  8 ++++++++
 zathura.c     |  5 ++---
 zathura.h     | 10 ++++++++++
 5 files changed, 43 insertions(+), 6 deletions(-)

diff --git a/callbacks.c b/callbacks.c
index 0d9a549..1c49df0 100644
--- a/callbacks.c
+++ b/callbacks.c
@@ -106,6 +106,12 @@ cb_view_vadjustment_value_changed(GtkAdjustment* GIRARA_UNUSED(adjustment), gpoi
       }
     } else {
       zathura_page_set_visibility(page, false);
+      /* if the page is not visible and not cached, but still has a surface, we
+       * need to get rid of the surface */
+      if (zathura_page_widget_have_surface(ZATHURA_PAGE(page_widget)) == true &&
+          zathura_page_cache_is_cached(zathura, zathura_page_get_index(page)) == false) {
+        zathura_page_widget_update_surface(ZATHURA_PAGE(page_widget), NULL);
+      }
 
       girara_list_t* results = NULL;
       g_object_get(page_widget, "search-results", &results, NULL);
diff --git a/page-widget.c b/page-widget.c
index 75694a6..adf69da 100644
--- a/page-widget.c
+++ b/page-widget.c
@@ -506,11 +506,16 @@ zathura_page_widget_update_surface(ZathuraPage* widget, cairo_surface_t* surface
   mutex_lock(&(priv->lock));
   if (priv->surface != NULL) {
     cairo_surface_destroy(priv->surface);
+    priv->surface = NULL;
   }
   priv->render_requested = false;
-  priv->surface = surface;
-  if (priv->surface != NULL) {
-    cairo_surface_reference(surface);
+  if (surface != NULL) {
+    /* if we're not visible or not cached, we don't care about the surface */
+    if (zathura_page_get_visibility(priv->page) == true ||
+        zathura_page_cache_is_cached(priv->zathura, zathura_page_get_index(priv->page)) == true) {
+      priv->surface = surface;
+      cairo_surface_reference(surface);
+    }
   }
   mutex_unlock(&(priv->lock));
   /* force a redraw here */
@@ -876,3 +881,12 @@ zathura_page_widget_update_view_time(ZathuraPage* widget)
     priv->last_view = g_get_real_time();
   }
 }
+
+bool
+zathura_page_widget_have_surface(ZathuraPage* widget)
+{
+  g_return_val_if_fail(ZATHURA_IS_PAGE(widget) == TRUE, false);
+  zathura_page_widget_private_t* priv = ZATHURA_PAGE_GET_PRIVATE(widget);
+  return priv->surface != NULL;
+}
+
diff --git a/page-widget.h b/page-widget.h
index 5609e78..b9a1c38 100644
--- a/page-widget.h
+++ b/page-widget.h
@@ -88,4 +88,12 @@ zathura_link_t* zathura_page_widget_link_get(ZathuraPage* widget, unsigned int i
  */
 void zathura_page_widget_update_view_time(ZathuraPage* widget);
 
+/**
+ * Check if we have a surface.
+ *
+ * @param widget the widget
+ * @returns true if the widget has a surface, false otherwise
+ */
+bool zathura_page_widget_have_surface(ZathuraPage* widget);
+
 #endif
diff --git a/zathura.c b/zathura.c
index 4bf53a6..5506c2c 100644
--- a/zathura.c
+++ b/zathura.c
@@ -54,7 +54,6 @@ typedef struct position_set_delayed_s {
 } position_set_delayed_t;
 
 static gboolean document_info_open(gpointer data);
-static bool zathura_page_cache_is_cached(zathura_t* zathura, unsigned int page_index);
 static ssize_t zathura_page_cache_lru_invalidate(zathura_t* zathura);
 static void zathura_page_cache_invalidate_all(zathura_t* zathura);
 static bool zathura_page_cache_is_full(zathura_t* zathura, bool* result);
@@ -1364,7 +1363,7 @@ zathura_jumplist_save(zathura_t* zathura)
   }
 }
 
-static bool
+bool
 zathura_page_cache_is_cached(zathura_t* zathura, unsigned int page_index)
 {
   g_return_val_if_fail(zathura != NULL, false);
@@ -1452,7 +1451,7 @@ zathura_page_cache_add(zathura_t* zathura, unsigned int page_index)
 
   g_return_if_fail(page != NULL);
 
-  if (zathura_page_cache_is_cached(zathura, page_index)) {
+  if (zathura_page_cache_is_cached(zathura, page_index) == true) {
     return;
   }
 
diff --git a/zathura.h b/zathura.h
index cafbc34..13df384 100644
--- a/zathura.h
+++ b/zathura.h
@@ -421,4 +421,14 @@ bool zathura_jumplist_load(zathura_t* zathura, const char* file);
  */
 void zathura_page_cache_add(zathura_t* zathura, unsigned int page_index);
 
+/**
+ * Checks if the given page is cached
+ *
+ * @param zathura The zathura session
+ * @param page_index The index of the page that may be cached
+ *
+ * @return true if page is cached otherwise false
+ */
+bool zathura_page_cache_is_cached(zathura_t* zathura, unsigned int page_index);
+
 #endif // ZATHURA_H