Panda3D 中不规则直柱体范围检测算法

以下是基于 Panda3D 的代码，可以精确计算出任意一个坐标点是否在不规则直柱体范围内：

from panda3d.core import *
from direct.showbase.ShowBase import ShowBase

class MyApp(ShowBase):
    def __init__(self):
        ShowBase.__init__(self)
        
        # 8个点的坐标
        points = [[67.85213470458984, -27.81583023071289, 0.0],
                  [44.97549819946289, -30.375598907470703, 0.0],
                  [44.97549819946289, -30.375598907470703, 52.0],
                  [71.8885726928711, -28.21024513244629, 52.0],
                  [68.07453155517578, -29.803424835205078, 0.0],
                  [45.19790267944336, -32.36319351196289, 0.0],
                  [45.19790267944336, -32.36319351196289, 52.0],
                  [72.11096954345703, -30.197839736938477, 52.0]]
        
        # 创建不规则直柱体
        geom = GeomVertexData('shape', GeomVertexFormat.getV3(), Geom.UHStatic)
        vertex = GeomVertexWriter(geom, 'vertex')
        for point in points:
            vertex.addData3f(*point)
        
        tris = [(0, 1, 4), (4, 1, 5), (1, 2, 5), (5, 2, 6),
                (2, 3, 6), (6, 3, 7), (3, 0, 7), (7, 0, 4),
                (0, 3, 1), (1, 3, 2), (4, 5, 7), (7, 5, 6)]
        
        prim = GeomTriangles(Geom.UHStatic)
        for tri in tris:
            prim.addVertices(*tri)
        
        prim.closePrimitive()
        geom.addPrimitive(prim)
        
        node = GeomNode('shape')
        node.addGeom(geom)
        self.shape = render.attachNewNode(node)
        
        # 验证一个点是否在直柱体范围内
        test_point = Point3(60.0, -30.0, 26.0)
        if self.is_point_inside_shape(test_point):
            print('Point is inside shape!')
        else:
            print('Point is outside shape!')
    
    def is_point_inside_shape(self, point):
        # 将点转换为局部坐标系中的坐标
        local_point = self.shape.getRelativePoint(self.shape.getParent(), point)
        
        # 创建一个射线，从该点向上射出
        ray = CollisionRay(local_point, Vec3(0, 0, 1))
        ray_node = CollisionNode('shape_ray')
        ray_node.addSolid(ray)
        ray_np = self.shape.attachNewNode(ray_node)
        
        # 进行射线碰撞检测
        queue = CollisionHandlerQueue()
        base.cTrav.traverse(self.shape)
        base.cTrav.addCollider(ray_np, queue)
        
        # 如果碰撞队列中有碰撞信息，说明该点在直柱体范围内
        if queue.getNumEntries() > 0:
            return True
        else:
            return False

app = MyApp()
app.run()

代码中，我们通过GeomVertexData和GeomTriangles创建了一个不规则直柱体，并将其添加到了场景图中。然后我们实现了is_point_inside_shape方法，该方法将一个点转换为局部坐标系中的坐标，并通过创建一个射线，并进行碰撞检测的方式，判断该点是否在直柱体范围内。最后，我们在MyApp的构造函数中调用了is_point_inside_shape方法，传入了一个测试点，以验证该方法的正确性。