写一个带 AABB的Octree算法的C++实现

非常感谢您的提问。以下是一个简单的带 AABB 的 Octree 算法的 C 实现：

#include <stdio.h>
#include <stdlib.h>

#define MAX_DEPTH 8

typedef struct {
    float x, y, z;
} Vector3;

typedef struct {
    Vector3 min, max;
} AABB;

typedef struct OctreeNode OctreeNode;
struct OctreeNode {
    AABB bounds;
    OctreeNode* children[8];
};

OctreeNode* createOctreeNode(AABB bounds, int depth) {
    OctreeNode* node = (OctreeNode*)malloc(sizeof(OctreeNode));
    node->bounds = bounds;
    for (int i = 0; i < 8; i++) {
        node->children[i] = NULL;
    }
    return node;
}

void insertOctreeNode(OctreeNode* node, AABB bounds, int depth) {
    if (depth >= MAX_DEPTH) {
        return;
    }
    Vector3 center = {
        (bounds.min.x + bounds.max.x) / 2,
        (bounds.min.y + bounds.max.y) / 2,
        (bounds.min.z + bounds.max.z) / 2
    };
    int index = 0;
    if (bounds.min.x > center.x) index |= 1;
    if (bounds.min.y > center.y) index |= 2;
    if (bounds.min.z > center.z) index |= 4;
    if (node->children[index] == NULL) {
        AABB childBounds = {
            { center.x, center.y, center.z },
            { bounds.max.x, bounds.max.y, bounds.max.z }
        };
        node->children[index] = createOctreeNode(childBounds, depth + 1);
    }
    insertOctreeNode(node->children[index], bounds, depth + 1);
}

void printOctreeNode(OctreeNode* node) {
    printf("Bounds: (%f, %f, %f) - (%f, %f, %f)\n", node->bounds.min.x, node->bounds.min.y, node->bounds.min.z, node->bounds.max.x, node->bounds.max.y, node->bounds.max.z);
    for (int i = 0; i < 8; i++) {
        if (node->children[i] != NULL) {
            printf("Child %d:\n", i);
            printOctreeNode(node->children[i]);
        }
    }
}

int main() {
    AABB rootBounds = {
        { -1, -1, -1 },
        { 1, 1, 1 }
    };
    OctreeNode* rootNode = createOctreeNode(rootBounds, 0);
    AABB bounds1 = {
        { -0.5, -0.5, -0.5 },
        { 0.5, 0.5, 0.5 }
    };
    insertOctreeNode(rootNode, bounds1, 0);
    AABB bounds2 = {
        { 0.5, 0.5, 0.5 },
        { 1, 1, 1 }
    };
    insertOctreeNode(rootNode, bounds2, 0);
    printOctreeNode(rootNode);
    return 0;
}

希望这个实现能够帮助您理解带 AABB 的 Octree 算法。如果您有任何问题或建议，请随时告诉我。