Python超人-宇宙模拟器

objs/halley_comet.py

@@ -49,7 +49,8 @@ class HalleComet(RockSnow):
         }
         super().__init__(**params)
         # create_cone(radius, height, subdivisions, r=0.1)
-        self.comet_info = (0.18, 2.0, 100, 0.2)
+        # self.comet_info = (0.18, 2.0, 100, 0.2)
+        self.comet_info = (0.03, 0.18, 1.5, 100)
 
 
 from ursina.prefabs.primitives import Shader

simulators/ursina/entities/planet.py

@@ -18,7 +18,7 @@ from common.color_utils import adjust_brightness, conv_to_vec4_color, get_invers
 from common.func import find_file
 from simulators.views.body_view import BodyView
 from simulators.ursina.ursina_mesh import create_sphere, create_torus, create_arrow_line, create_line, create_label, \
-    create_cone
+    create_cone, create_frustum
 import math
 
 
@@ -182,10 +182,9 @@ class Planet(Entity):
                 create_rings(self)
 
     def create_comet_trail(self, comet_info):
-        # cone = create_cone(0.25, 1.5, 100, 0.18)
-        cone = create_cone(*comet_info)
+        comet_mesh = create_frustum(*comet_info)
         texture = find_texture("comet_trail.png")
-        self.comet_trail = Entity(parent=self, model=cone, texture=texture, scale=20,
+        self.comet_trail = Entity(parent=self, model=comet_mesh, texture=texture, scale=20,
                                   position=(0, 0, 0),
                                   rotation=(0, 90, 90), double_sided=True, alpha=0.8)
 

simulators/ursina/ursina_mesh.py

@@ -116,6 +116,62 @@ def create_cone(radius, height, subdivisions, r=0.1):
     return Mesh(vertices=verts, triangles=tris, normals=normals, uvs=uvs, mode='triangle')
 
 
+import math
+
+
+def create_frustum(bottom_radius, top_radius, height, subdivisions):
+    """
+    创建一个圆台
+    @param bottom_radius: 圆台底部的半径
+    @param top_radius: 圆台顶部的半径
+    @param height: 圆台的高度
+    @param subdivisions: 细分数，用于控制圆台的光滑度
+    @return: Mesh对象，表示创建的圆台
+    """
+    verts = []  # 顶点列表
+    tris = []  # 三角面索引列表
+    normals = []  # 法线列表
+    uvs = []  # UV坐标列表
+
+    # 生成圆台底部的顶点和UV坐标
+    for i in range(subdivisions):
+        angle = 2 * math.pi * i / subdivisions
+        x = bottom_radius * math.cos(angle)
+        z = bottom_radius * math.sin(angle)
+        verts.append(Vec3(x, 0, z))
+        uvs.append(Vec2(i / subdivisions, 0))
+
+    # 生成圆台顶部的顶点和UV坐标
+    for i in range(subdivisions):
+        angle = 2 * math.pi * i / subdivisions
+        x = top_radius * math.cos(angle)
+        z = top_radius * math.sin(angle)
+        verts.append(Vec3(x, height, z))
+        uvs.append(Vec2(i / subdivisions, 1))
+
+    # 生成圆台侧面的顶点、法线和三角面
+    for i in range(subdivisions):
+        # 底部顶点索引
+        bottom_index = i
+        # 顶部顶点索引
+        top_index = i + subdivisions
+        # 下一个底部顶点索引
+        next_bottom_index = (i + 1) % subdivisions
+        # 下一个顶部顶点索引
+        next_top_index = (i + 1) % subdivisions + subdivisions
+
+        # 侧面三角形
+        tris.append((bottom_index, next_bottom_index, top_index))
+        tris.append((next_bottom_index, next_top_index, top_index))
+
+        # 侧面法线
+        normal = (verts[top_index] - verts[bottom_index]).cross(
+            verts[next_bottom_index] - verts[bottom_index]).normalized()
+        normals.append(normal)
+        normals.append(normal)
+
+    return Mesh(vertices=verts, triangles=tris, normals=normals, uvs=uvs, mode='triangle')
+
 def create_cylinder(radius, height, subdivisions):
     """
     创建一个圆柱体