以递归遍历的方式搜索四叉树quadtree的每个节点,获取区域范围与射线相交的叶子节点中存储的三角面索引,并且根据索引得到三角面的顶点坐标和法向量,最后用射线与三角面进行求交运算,最后遍历完整棵四叉树,得到射线与所有三角面的交点,返回交点坐标和索引信息。请编写一段完整的matlab代码。
时间: 2024-03-16 17:44:41 浏览: 162
以下是一个简单的Matlab代码,用于搜索四叉树quadtree的每个节点,获取区域范围与射线相交的叶子节点中存储的三角面索引,并且根据索引得到三角面的顶点坐标和法向量,最后用射线与三角面进行求交运算,最后遍历完整棵四叉树,得到射线与所有三角面的交点,返回交点坐标和索引信息。
```matlab
function [vertices, normals, indices] = quadtree_ray_tracing(root, ray_origin, ray_direction)
% Recursive function to traverse the quadtree and find intersections
% with ray
% Check if current node is a leaf node
if isempty(root.children)
% Check if ray intersects with leaf node's bounding box
intersection = ray_box_intersection(root.box, ray_origin, ray_direction);
if intersection
% Get triangle indices from leaf node
indices = root.indices;
% Get vertices and normals from indices
[vertices, normals] = get_vertices_normals(indices);
% Find ray-triangle intersections
[intersections, ~] = TriangleRayIntersection(ray_origin, ray_direction, vertices);
% Return intersection information
if ~isempty(intersections)
% Find closest intersection
[~, index] = min(intersections);
intersection_point = vertices(index, :);
intersection_normal = normals(index, :);
return
end
end
else
% Recursively traverse child nodes
for i = 1:length(root.children)
child = root.children(i);
intersection = ray_box_intersection(child.box, ray_origin, ray_direction);
if intersection
[vertices, normals, indices] = quadtree_ray_tracing(child, ray_origin, ray_direction);
if ~isempty(indices)
return
end
end
end
end
% No intersection found
vertices = [];
normals = [];
indices = [];
end
function [vertices, normals] = get_vertices_normals(indices)
% Get vertices and normals from triangle indices
% Load mesh data
mesh_data = load('mesh_data.mat');
vertices = mesh_data.vertices;
normals = mesh_data.normals;
% Get vertices and normals for each triangle
vertices = vertices(indices, :);
normals = normals(indices, :);
end
function intersection = ray_box_intersection(box, ray_origin, ray_direction)
% Check if ray intersects with bounding box
% Check for intersection with each face of bounding box
tmin = (box([1 2 3]) - ray_origin) ./ ray_direction;
tmax = (box([4 5 6]) - ray_origin) ./ ray_direction;
tmin = max(min(tmin, tmax), 0);
tmax = min(max(tmin, tmax), 1);
intersection = all(tmax >= tmin);
end
function [t, u, v] = TriangleRayIntersection(Orig, Dir, Verts)
% Calculate ray-triangle intersection
% Triangle vertices
v1 = Verts(1,:);
v2 = Verts(2,:);
v3 = Verts(3,:);
% Edge vectors
e1 = v2 - v1;
e2 = v3 - v1;
% Normal vector
n = cross(e1, e2);
% Check if ray is parallel to triangle
ndotd = dot(n, Dir);
if abs(ndotd) < eps
t = Inf;
u = 0;
v = 0;
return
end
% Calculate intersection point
w = Orig - v1;
ndotw = dot(n, w);
t = -ndotw / ndotd;
% Check if intersection is behind ray origin
if t < 0
t = Inf;
u = 0;
v = 0;
return
end
% Calculate barycentric coordinates
q = cross(Dir, e2);
u = dot(w, q) / dot(n, q);
p = cross(w, e1);
v = dot(Dir, p) / dot(n, p);
% Check if point is inside triangle
if u < 0 || v < 0 || u + v > 1
t = Inf;
u = 0;
v = 0;
return
end
end
```
请注意,上面的代码只是一个简单的示例,需要根据具体的应用场景和数据格式进行修改和调整。同时,代码中还需要加载存储三角面数据的文件,这里假设该数据以matlab格式存储,文件名为`mesh_data.mat`,包含`vertices`和`normals`两个变量,分别存储所有三角面的顶点坐标和法向量。
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