src/engine/scene.c

   1 #include "scene.h"
   2
   3 #include <stdlib.h>
   4
   5 #include "engine/logger.h"
   6
   7 Scene* currentScene = NULL;
   8
   9
  10
  11 Scene* newScene() {
  12         Scene* scene = malloc(sizeof(Scene));
  13         *scene = (Scene) { .parent = NULL,
  14                            .numChildren = 0u,
  15                            .children = NULL,
  16                            .transform = identity(),
  17                            .solid = NULL };
  18         return scene;
  19 }
  20
  21 void insertChildScene(Scene* scene, Scene* newChild) {
  22         if (!scene || !newChild) {
  23                 return;
  24         }
  25         if (newChild->parent) {
  26                 logError(
  27                         "Cannot insert scene 0x%p as child of 0x%p, because it is already child of 0x%p",
  28                         newChild,
  29                         scene,
  30                         newChild->parent);
  31                 return;
  32         }
  33
  34         scene->children = realloc(scene->children, ++(scene->numChildren) * sizeof(Scene*));
  35         scene->children[scene->numChildren - 1] = newChild;
  36
  37         newChild->parent = scene;
  38 }
  39
  40 void reparentScene(Scene* scene, Scene* newParent) {
  41         if (!scene) {
  42                 return;
  43         }
  44
  45         if (scene->parent) {
  46                 Scene* parent = scene->parent;
  47                 size_t indexInParent = parent->numChildren;
  48                 for (size_t i = 0; i < parent->numChildren; ++i) {
  49                         if (parent->children[i] == scene) {
  50                                 indexInParent = i;
  51                                 break;
  52                         }
  53                 }
  54                 // This includes the hopefully impossible case where parent->numChildren == 0
  55                 if (indexInParent == parent->numChildren) {
  56                         logError("Scene %p not found in children of parent %p", scene, parent);
  57                 }
  58                 else {
  59                         for (size_t i = indexInParent; i < parent->numChildren - 1; ++i) {
  60                                 parent->children[i] = parent->children[i + 1];
  61                         }
  62                         parent->children = realloc(parent->children, --(parent->numChildren) * sizeof(Scene*));
  63                 }
  64         }
  65
  66         scene->parent = NULL;
  67
  68         insertChildScene(newParent, scene);
  69 }