Adding linked list insertion sort and sorting entities by draw priority.

src/ecs.c

@@ -114,7 +114,8 @@ static inline int action_draw_component(elem_t *elem, va_list args __attribute__
 {
     component_t *component = elem->data;
 
-    if(component->draw) if(component->draw(component)) return EXIT_FAILURE;
+    if(component->draw)
+        if(component->draw(component)) return EXIT_FAILURE;
 
     return EXIT_SUCCESS;
 }
@@ -172,10 +173,18 @@ static inline int action_draw_entity(elem_t *elem, va_list args __attribute__((u
     return draw_entity((entity_t *)elem->data);
 }
 
+// No args
+static inline bool condition_is_draw_priority_higher(elem_t *elem, va_list args)
+{
+    return ((entity_t *)elem->data)->draw_priority > ((entity_t *)elem->next->data)->draw_priority;
+}
+
 inline int entity_manager_draw(entity_manager_t *entity_manager)
 {
     assert("Entity manager cannot be NULL" && entity_manager);
 
+    linked_list_insertion_sort(&entity_manager->entities, condition_is_draw_priority_higher);
+
     if(linked_list_for_each(&entity_manager->entities, action_draw_entity)) return EXIT_FAILURE;
 
     return EXIT_SUCCESS;

src/headers/linked_list.h

@@ -286,4 +286,15 @@ int linked_list_for_each(const linked_list_t *linked_list, const action_t action
 */
 int linked_list_for_eachv(const linked_list_t *linked_list, const action_t action, va_list args);
 
+/**
+ * @brief Do an insertion sort data of the given linked list.
+ * The condition return true to swap element's data with next one.
+ *
+ * @param linked_list   Pointer to an linked list
+ * @param action        Action to apply
+ *
+ * @return EXIT_SUCCESS, EXIT_FAILURE on error.
+*/
+void linked_list_insertion_sort(linked_list_t *linked_list, const condition_t condition, ...);
+
 #endif // LINKED_LIST_H

src/linked_list.c

@@ -275,13 +275,6 @@ elem_t *linked_list_pop_front(linked_list_t *linked_list)
     return elem;
 }
 
-inline bool linked_list_is_empty(const linked_list_t *linked_list)
-{
-    assert("Linked list cannot be NULL" && linked_list);
-
-   return !linked_list->first;
-}
-
 elem_t *linked_list_get(const linked_list_t *linked_list, size_t index)
 {
     assert("Linked list cannot be NULL" && linked_list);
@@ -506,3 +499,41 @@ int linked_list_for_eachv(const linked_list_t *linked_list, const action_t actio
 
     return EXIT_SUCCESS;
 }
+
+static inline void swap_elems_data(elem_t *elem_a, elem_t *elem_b)
+{
+    void *tmp_data = elem_a->data;
+    elem_a->data = elem_b->data;
+    elem_b->data = tmp_data;
+}
+
+void linked_list_insertion_sort(linked_list_t *linked_list, const condition_t condition, ...)
+{
+    assert("Linked list cannot be NULL" && linked_list);
+    assert("Condition cannot be NULL" && condition);
+
+    va_list args;
+    va_start(args, condition);
+
+    elem_t *actual_elem = linked_list->first;
+    elem_t *next_elem;
+
+    while(actual_elem->next)
+    {
+        next_elem = actual_elem->next;
+
+        va_list args_copy;
+        va_copy(args_copy, args);
+
+        if(condition(actual_elem, args_copy))
+        {
+            swap_elems_data(actual_elem, next_elem);
+        }
+
+        va_end(args_copy);
+
+        actual_elem = next_elem;
+    }
+
+    va_end(args);
+}