Add option for right-to-left layout (fixes #754)

zathura/callbacks.c

@@ -329,7 +329,10 @@ cb_page_layout_value_changed(girara_session_t* session, const char* name, girara
   unsigned int page_padding = 1;
   girara_setting_get(zathura->ui.session, "page-padding", &page_padding);
 
-  page_widget_set_mode(zathura, page_padding, pages_per_row, first_page_column);
+  bool page_right_to_left = false;
+  girara_setting_get(zathura->ui.session, "page-right-to-left", &page_right_to_left);
+
+  page_widget_set_mode(zathura, page_padding, pages_per_row, first_page_column, page_right_to_left);
   zathura_document_set_page_layout(zathura->document, page_padding, pages_per_row, first_page_column);
 }
 

zathura/config.c

@@ -191,6 +191,8 @@ config_load_default(zathura_t* zathura)
   girara_setting_add(gsession, "pages-per-row",         &int_value,   INT,    false, _("Number of pages per row"),  cb_page_layout_value_changed, NULL);
   int_value = 1;
   girara_setting_add(gsession, "first-page-column",     "1:2",        STRING, false, _("Column of the first page"), cb_page_layout_value_changed, NULL);
+  bool_value = false;
+  girara_setting_add(gsession, "page-right-to-left",    &bool_value,  BOOLEAN, false, _("Render pages from right to left"),  cb_page_layout_value_changed, NULL);
   float_value = 40;
   girara_setting_add(gsession, "scroll-step",           &float_value, FLOAT,  false, _("Scroll step"),              NULL, NULL);
   float_value = 40;

zathura/database-plain.c

@@ -27,6 +27,7 @@
 #define KEY_ZOOM                  "zoom"
 #define KEY_ROTATE                "rotate"
 #define KEY_PAGES_PER_ROW         "pages-per-row"
+#define KEY_PAGE_RIGHT_TO_LEFT    "page-right-to-left"
 #define KEY_FIRST_PAGE_COLUMN     "first-page-column"
 #define KEY_POSITION_X            "position-x"
 #define KEY_POSITION_Y            "position-y"
@@ -560,6 +561,7 @@ plain_set_fileinfo(zathura_database_t* db, const char* file, zathura_fileinfo_t*
   g_key_file_set_integer(priv->history, name, KEY_ROTATE,            file_info->rotation);
   g_key_file_set_integer(priv->history, name, KEY_PAGES_PER_ROW,     file_info->pages_per_row);
   g_key_file_set_string(priv->history, name, KEY_FIRST_PAGE_COLUMN,  file_info->first_page_column_list);
+  g_key_file_set_boolean(priv->history, name, KEY_PAGE_RIGHT_TO_LEFT,file_info->page_right_to_left);
   g_key_file_set_double (priv->history, name, KEY_POSITION_X,        file_info->position_x);
   g_key_file_set_double (priv->history, name, KEY_POSITION_Y,        file_info->position_y);
   g_key_file_set_integer(priv->history, name, KEY_TIME,              time(NULL));
@@ -603,6 +605,9 @@ plain_get_fileinfo(zathura_database_t* db, const char* file, zathura_fileinfo_t*
   if (g_key_file_has_key(priv->history, name, KEY_FIRST_PAGE_COLUMN, NULL) == TRUE) {
     file_info->first_page_column_list = g_key_file_get_string(priv->history, name, KEY_FIRST_PAGE_COLUMN, NULL);
   }
+  if (g_key_file_has_key(priv->history, name, KEY_PAGE_RIGHT_TO_LEFT, NULL) == TRUE) {
+    file_info->page_right_to_left = g_key_file_get_boolean(priv->history, name, KEY_PAGE_RIGHT_TO_LEFT, NULL);
+  }
   if (g_key_file_has_key(priv->history, name, KEY_POSITION_X, NULL) == TRUE) {
     file_info->position_x        = g_key_file_get_double(priv->history, name, KEY_POSITION_X, NULL);
   }

zathura/database.h

@@ -15,6 +15,7 @@ typedef struct zathura_fileinfo_s {
   double zoom;
   unsigned int rotation;
   unsigned int pages_per_row;
+  bool page_right_to_left;
   char* first_page_column_list;
   double position_x;
   double position_y;

zathura/zathura.c

@@ -980,6 +980,7 @@ document_open(zathura_t* zathura, const char* path, const char* uri, const char*
     .rotation = 0,
     .pages_per_row = 0,
     .first_page_column_list = NULL,
+    .page_right_to_left = false,
     .position_x = 0,
     .position_y = 0
   };
@@ -1152,6 +1153,7 @@ document_open(zathura_t* zathura, const char* path, const char* uri, const char*
   unsigned int pages_per_row = 1;
   char* first_page_column_list = NULL;
   unsigned int page_padding = 1;
+  bool page_right_to_left = false;
 
   girara_setting_get(zathura->ui.session, "page-padding", &page_padding);
 
@@ -1177,7 +1179,9 @@ document_open(zathura_t* zathura, const char* path, const char* uri, const char*
   g_free(file_info.first_page_column_list);
   g_free(first_page_column_list);
 
-  page_widget_set_mode(zathura, page_padding, pages_per_row, first_page_column);
+  page_right_to_left = file_info.page_right_to_left;
+
+  page_widget_set_mode(zathura, page_padding, pages_per_row, first_page_column, page_right_to_left);
   zathura_document_set_page_layout(zathura->document, page_padding, pages_per_row, first_page_column);
 
   girara_set_view(zathura->ui.session, zathura->ui.page_widget);
@@ -1341,6 +1345,7 @@ save_fileinfo_to_db(zathura_t* zathura)
     .rotation = zathura_document_get_rotation(zathura->document),
     .pages_per_row = 1,
     .first_page_column_list = "1:2",
+    .page_right_to_left = false,
     .position_x = zathura_document_get_position_x(zathura->document),
     .position_y = zathura_document_get_position_y(zathura->document)
   };
@@ -1349,6 +1354,8 @@ save_fileinfo_to_db(zathura_t* zathura)
                      &(file_info.pages_per_row));
   girara_setting_get(zathura->ui.session, "first-page-column",
                      &(file_info.first_page_column_list));
+  girara_setting_get(zathura->ui.session, "page-right-to-left",
+                     &(file_info.page_right_to_left));
 
   /* save file info */
   zathura_db_set_fileinfo(zathura->database, path, &file_info);
@@ -1509,7 +1516,8 @@ statusbar_page_number_update(zathura_t* zathura)
 
 void
 page_widget_set_mode(zathura_t* zathura, unsigned int page_padding,
-                     unsigned int pages_per_row, unsigned int first_page_column)
+                     unsigned int pages_per_row, unsigned int first_page_column,
+                     bool page_right_to_left)
 {
   /* show at least one page */
   if (pages_per_row == 0) {
@@ -1540,6 +1548,9 @@ page_widget_set_mode(zathura_t* zathura, unsigned int page_padding,
     int y = (i + first_page_column - 1) / pages_per_row;
 
     GtkWidget* page_widget = zathura->pages[i];
+    if (page_right_to_left) {
+      x = pages_per_row - 1 - x;
+    }
 
     gtk_grid_attach(GTK_GRID(zathura->ui.page_widget), page_widget, x, y, 1, 1);
   }

zathura/zathura.h

@@ -404,9 +404,11 @@ bool adjust_view(zathura_t* zathura);
  * @param page_padding padding in pixels between pages
  * @param pages_per_row Number of shown pages per row
  * @param first_page_column Column on which first page start
+ * @param page_right_to_left Render pages right to left
  */
 void page_widget_set_mode(zathura_t* zathura, unsigned int page_padding,
-                          unsigned int pages_per_row, unsigned int first_page_column);
+                          unsigned int pages_per_row, unsigned int first_page_column,
+                          bool page_right_to_left);
 
 /**
  * Updates the page number in the statusbar. Note that 1 will be added to the