libview: Split ev_pixbuf_cache_get_selection_surface into two functions

ev_pixbuf_cache_get_selection_surface returns the selection surface, and
new function ev_pixbuf_cache_get_selection_region returns the selection
region.

https://bugzilla.gnome.org/show_bug.cgi?id=669022

origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-10&id=90d6580

3 files changed, 111 insertions, 36 deletions

diff --git a/libview/ev-pixbuf-cache.c b/libview/ev-pixbuf-cache.c
index 4c890030..542775d0 100644
--- a/libview/ev-pixbuf-cache.c
+++ b/libview/ev-pixbuf-cache.c
@@ -20,14 +20,17 @@ typedef struct _CacheJobInfo
 	/* Selection data. 
 	 * Selection_points are the coordinates encapsulated in selection.
 	 * target_points is the target selection size. */
-	EvRectangle      selection_points;
 	EvRectangle      target_points;
 	EvSelectionStyle selection_style;
 	gboolean         points_set;
 	
 	cairo_surface_t *selection;
-	cairo_region_t  *selection_region;
 	gdouble          selection_scale;
+	EvRectangle      selection_points;
+
+	cairo_region_t *selection_region;
+	gdouble         selection_region_scale;
+	EvRectangle     selection_region_points;
 } CacheJobInfo;
 
 struct _EvPixbufCache
@@ -286,11 +289,15 @@ copy_job_to_job_info (EvJobRender   *job_render,
 		}
 
 		job_info->selection_points = job_render->selection_points;
-		job_info->selection_region = cairo_region_reference (job_render->selection_region);
 		job_info->selection = cairo_surface_reference (job_render->selection);
 		job_info->selection_scale = job_render->scale;
 		set_device_scale_on_surface (job_info->selection, job_info->device_scale);
 		g_assert (job_info->selection_points.x1 >= 0);
+
+		job_info->selection_region_points = job_render->selection_points;
+		job_info->selection_region = cairo_region_reference (job_render->selection_region);
+		job_info->selection_region_scale = job_render->scale;
+
 		job_info->points_set = TRUE;
 	}
 
@@ -868,11 +875,22 @@ new_selection_surface_needed (EvPixbufCache *pixbuf_cache,
 	return FALSE;
 }
 
+static gboolean
+new_selection_region_needed (EvPixbufCache *pixbuf_cache,
+                             CacheJobInfo  *job_info,
+                             gint           page,
+                             gfloat         scale)
+{
+	if (job_info->selection_region || job_info->points_set)
+		return job_info->selection_region_scale != scale;
+	return FALSE;
+}
+
 static void
-clear_selection_if_needed (EvPixbufCache *pixbuf_cache,
-			   CacheJobInfo  *job_info,
-			   gint           page,
-			   gfloat         scale)
+clear_selection_surface_if_needed (EvPixbufCache *pixbuf_cache,
+                                   CacheJobInfo  *job_info,
+                                   gint           page,
+                                   gfloat         scale)
 {
 	if (new_selection_surface_needed (pixbuf_cache, job_info, page, scale)) {
 		if (job_info->selection)
@@ -882,6 +900,20 @@ clear_selection_if_needed (EvPixbufCache *pixbuf_cache,
 	}
 }
 
+static void
+clear_selection_region_if_needed (EvPixbufCache *pixbuf_cache,
+                                  CacheJobInfo  *job_info,
+                                  gint           page,
+                                  gfloat         scale)
+{
+	if (new_selection_region_needed (pixbuf_cache, job_info, page, scale)) {
+		if (job_info->selection_region)
+			cairo_region_destroy (job_info->selection_region);
+		job_info->selection_region = NULL;
+		job_info->selection_region_points.x1 = -1;
+	}
+}
+
 /* Clears the cache of jobs and pixbufs.
  */
 void
@@ -944,9 +976,8 @@ ev_pixbuf_cache_style_changed (EvPixbufCache *pixbuf_cache)
 
 cairo_surface_t *
 ev_pixbuf_cache_get_selection_surface (EvPixbufCache   *pixbuf_cache,
-				       gint             page,
-				       gfloat           scale,
-				       cairo_region_t **region)
+                                       gint             page,
+                                       gfloat           scale)
 {
 	CacheJobInfo *job_info;
 
@@ -965,15 +996,12 @@ ev_pixbuf_cache_get_selection_surface (EvPixbufCache   *pixbuf_cache,
 	/* If we have a running job, we just return what we have under the
 	 * assumption that it'll be updated later and we can scale it as need
 	 * be */
-	if (job_info->job && EV_JOB_RENDER (job_info->job)->include_selection) {
-		if (region)
-			*region = job_info->selection_region;
+	if (job_info->job && EV_JOB_RENDER (job_info->job)->include_selection)
 		return job_info->selection;
-	}
 
 	/* Now, lets see if we need to resize the image.  If we do, we clear the
 	 * old one. */
-	clear_selection_if_needed (pixbuf_cache, job_info, page, scale * job_info->device_scale);
+	clear_selection_surface_if_needed (pixbuf_cache, job_info, page, scale);
 
 	/* Finally, we see if the two scales are the same, and get a new pixbuf
 	 * if needed.  We do this synchronously for now.  At some point, we
@@ -999,15 +1027,7 @@ ev_pixbuf_cache_get_selection_surface (EvPixbufCache   *pixbuf_cache,
 		rc = ev_render_context_new (ev_page, 0, scale * job_info->device_scale);
 		g_object_unref (ev_page);
 
-		if (job_info->selection_region)
-			cairo_region_destroy (job_info->selection_region);
-		job_info->selection_region =
-			ev_selection_get_selection_region (EV_SELECTION (pixbuf_cache->document),
-							   rc, job_info->selection_style,
-							   &(job_info->target_points));
-
 		get_selection_colors (EV_VIEW (pixbuf_cache->view), &text, &base);
-
 		ev_selection_render_selection (EV_SELECTION (pixbuf_cache->document),
 					       rc, &(job_info->selection),
 					       &(job_info->target_points),
@@ -1020,11 +1040,64 @@ ev_pixbuf_cache_get_selection_surface (EvPixbufCache   *pixbuf_cache,
 		g_object_unref (rc);
 		ev_document_doc_mutex_unlock ();
 	}
-	if (region)
-		*region = job_info->selection_region;
 	return job_info->selection;
 }
 
+cairo_region_t *
+ev_pixbuf_cache_get_selection_region (EvPixbufCache *pixbuf_cache,
+                                      gint           page,
+                                      gfloat         scale)
+{
+	CacheJobInfo *job_info;
+
+	/* the document does not implement the selection interface */
+	if (!EV_IS_SELECTION (pixbuf_cache->document))
+		return NULL;
+
+	job_info = find_job_cache (pixbuf_cache, page);
+	if (job_info == NULL)
+		return NULL;
+
+	/* No selection on this page */
+	if (!job_info->points_set)
+		return NULL;
+
+	/* If we have a running job, we just return what we have under the
+	 * assumption that it'll be updated later and we can scale it as need
+	 * be */
+	if (job_info->job && EV_JOB_RENDER (job_info->job)->include_selection)
+		return job_info->selection_region;
+
+	/* Now, lets see if we need to resize the region.  If we do, we clear the
+	 * old one. */
+	clear_selection_region_if_needed (pixbuf_cache, job_info, page, scale);
+
+	/* Finally, we see if the two scales are the same, and get a new region
+	 * if needed.
+	 */
+	if (ev_rect_cmp (&(job_info->target_points), &(job_info->selection_region_points))) {
+		EvRenderContext *rc;
+		EvPage *ev_page;
+
+		ev_document_doc_mutex_lock ();
+		ev_page = ev_document_get_page (pixbuf_cache->document, page);
+		rc = ev_render_context_new (ev_page, 0, scale);
+		g_object_unref (ev_page);
+
+		if (job_info->selection_region)
+			cairo_region_destroy (job_info->selection_region);
+		job_info->selection_region =
+			ev_selection_get_selection_region (EV_SELECTION (pixbuf_cache->document),
+							   rc, job_info->selection_style,
+							   &(job_info->target_points));
+		job_info->selection_region_points = job_info->target_points;
+		job_info->selection_region_scale = scale;
+		g_object_unref (rc);
+		ev_document_doc_mutex_unlock ();
+	}
+	return job_info->selection_region;
+}
+
 static void
 update_job_selection (CacheJobInfo    *job_info,
 		      EvViewSelection *selection)
diff --git a/libview/ev-pixbuf-cache.h b/libview/ev-pixbuf-cache.h
index a20b7518..5617ca9b 100644
--- a/libview/ev-pixbuf-cache.h
+++ b/libview/ev-pixbuf-cache.h
@@ -78,8 +78,10 @@ void           ev_pixbuf_cache_set_inverted_colors  (EvPixbufCache *pixbuf_cache
 /* Selection */
 cairo_surface_t *ev_pixbuf_cache_get_selection_surface (EvPixbufCache   *pixbuf_cache,
 							gint             page,
-							gfloat           scale,
-							cairo_region_t **region);
+							gfloat           scale);
+cairo_region_t *ev_pixbuf_cache_get_selection_region (EvPixbufCache *pixbuf_cache,
+						      gint           page,
+						      gfloat         scale);
 void           ev_pixbuf_cache_set_selection_list   (EvPixbufCache *pixbuf_cache,
 						     GList         *selection_list);
 GList         *ev_pixbuf_cache_get_selection_list   (EvPixbufCache *pixbuf_cache);
diff --git a/libview/ev-view.c b/libview/ev-view.c
index 99604221..e4a351f8 100644
--- a/libview/ev-view.c
+++ b/libview/ev-view.c
@@ -5581,15 +5581,17 @@ draw_one_page (EvView       *view,
 			return;
 
 		selection_surface = ev_pixbuf_cache_get_selection_surface (view->pixbuf_cache,
-									   page,
-									   view->scale,
-									   &region);
+		                                                           page,
+		                                                           view->scale);
 		if (selection_surface) {
 			draw_surface (cr, selection_surface, overlap.x, overlap.y, offset_x, offset_y,
 				      width, height);
 			return;
 		}
 
+		region = ev_pixbuf_cache_get_selection_region (view->pixbuf_cache,
+		                                               page,
+		                                               view->scale);
 		if (region) {
 			double scale_x, scale_y;
 			GdkRGBA color;
@@ -7362,13 +7364,11 @@ merge_selection_region (EvView *view,
 		/* seed the cache with a new page.  We are going to need the new
 		 * region too. */
 		if (new_sel) {
-			cairo_region_t *tmp_region = NULL;
-
-			ev_pixbuf_cache_get_selection_surface (view->pixbuf_cache,
-							       cur_page,
-							       view->scale,
-							       &tmp_region);
+			cairo_region_t *tmp_region;
 
+			tmp_region = ev_pixbuf_cache_get_selection_region (view->pixbuf_cache,
+			                                                   cur_page,
+			                                                   view->scale);
 			if (tmp_region && !cairo_region_is_empty (tmp_region)) {
 				new_sel->covered_region = cairo_region_reference (tmp_region);
 			}