universe@21: /*
universe@21:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
universe@21:  * Copyright 2023 Mike Becker. All rights reserved.
universe@21:  *
universe@21:  * Redistribution and use in source and binary forms, with or without
universe@21:  * modification, are permitted provided that the following conditions are met:
universe@21:  *
universe@21:  *   1. Redistributions of source code must retain the above copyright
universe@21:  *      notice, this list of conditions and the following disclaimer.
universe@21:  *
universe@21:  *   2. Redistributions in binary form must reproduce the above copyright
universe@21:  *      notice, this list of conditions and the following disclaimer in the
universe@21:  *      documentation and/or other materials provided with the distribution.
universe@21:  *
universe@21:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@21:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@21:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@21:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@21:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@21:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@21:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@21:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@21:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@21:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@21:  * POSSIBILITY OF SUCH DAMAGE.
universe@21:  */
universe@21: 
universe@21: #include "ascension/scene.h"
universe@21: #include "ascension/error.h"
universe@21: 
universe@21: #include <cx/linked_list.h>
universe@21: #include <assert.h>
universe@21: 
universe@21: void asc_scene_init(AscScene *scene) {
universe@21:     if (scene->root != NULL) {
universe@21:         asc_error("Scene is already initialized.");
universe@21:         return;
universe@21:     }
universe@21:     scene->root = asc_scene_node_create(NULL);
universe@21: }
universe@21: 
universe@21: void asc_scene_destroy(AscScene *scene) {
universe@21:     asc_scene_node_free(scene->root);
universe@21: }
universe@21: 
universe@21: AscSceneNode *asc_scene_node_create(AscSceneNode *parent) {
universe@21:     AscSceneNode *node = malloc(sizeof(AscSceneNode));
universe@21:     assert(node != NULL);
universe@21:     node->children = cxLinkedListCreateSimple(CX_STORE_POINTERS);
universe@21:     assert(node->children != NULL);
universe@21:     node->parent = NULL;
universe@21:     asc_scene_node_link(node, parent);
universe@21:     return node;
universe@21: }
universe@21: 
universe@21: void asc_scene_node_free(AscSceneNode *node) {
universe@21:     if (node == NULL) return;
universe@21:     while (cxListSize(node->children) > 0) {
universe@21:         AscSceneNode *child = cxListAt(node->children, 0);
universe@21:         asc_scene_node_free(child);
universe@21:     }
universe@21:     if (node->parent != NULL) {
universe@21:         cxListFindRemove(node->parent->children, node);
universe@21:     }
universe@21:     free(node);
universe@21: }
universe@21: 
universe@21: void asc_scene_node_link(
universe@21:         AscSceneNode *node,
universe@21:         AscSceneNode *parent
universe@21: ) {
universe@21:     if (node->parent == parent) return;
universe@21:     if (node->parent != NULL || parent == NULL) asc_scene_node_unlink(node);
universe@21:     if (parent != NULL) {
universe@21:         cxListAdd(parent->children, node);
universe@21:         node->parent = parent;
universe@21:     }
universe@21: }
universe@21: 
universe@21: void asc_scene_node_unlink(AscSceneNode *node) {
universe@21:     if (node->parent == NULL) return;
universe@21:     cxListFindRemove(node->parent->children, node);
universe@21:     node->parent = NULL;
universe@21: }