diff --git a/zathura/zathura.c b/zathura/zathura.c
index 4077a1c..2979324 100644
--- a/zathura/zathura.c
+++ b/zathura/zathura.c
@@ -1380,13 +1380,13 @@ position_set(zathura_t* zathura, double position_x, double position_y)
   }
 
   double comppos_x, comppos_y;
-  unsigned int page_id = zathura_document_get_current_page_number(zathura->document);
+  const unsigned int page_id = zathura_document_get_current_page_number(zathura->document);
 
   bool vertical_center = false;
   girara_setting_get(zathura->ui.session, "vertical-center", &vertical_center);
 
   /* xalign = 0.5: center horizontally (with the page, not the document) */
-  if (vertical_center) {
+  if (vertical_center == true) {
     /* yalign = 0.0: align page an viewport edges at the top               */
     page_number_to_position(zathura->document, page_id, 0.5, 0.0, &comppos_x, &comppos_y);
   } else {
@@ -1406,7 +1406,7 @@ position_set(zathura_t* zathura, double position_x, double position_y)
     /* center horizontally */
     if (adjust_mode == ZATHURA_ADJUST_BESTFIT ||
       adjust_mode == ZATHURA_ADJUST_WIDTH ||
-      zoom_center) {
+      zoom_center == true) {
         position_x = 0.5;
     }
   }