有构建板，支持多模型构建，但生成支撑的切片还有bug

tmp/test_simplifier.py

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+import numpy as np
+from stl import mesh
+
+def simplify_stl_grid(input_path, output_path, target_ratio=0.1):
+    m = mesh.Mesh.from_file(input_path)
+    vertices = m.vectors.reshape(-1, 3)
+    
+    min_v = vertices.min(axis=0)
+    max_v = vertices.max(axis=0)
+    bbox_size = max_v - min_v
+    max_dim = np.max(bbox_size)
+    
+    # Adjust resolution to rough target_ratio by guessing. 
+    # The number of vertices drops roughly by (resolution_factor)^2.
+    # So if we want 10% faces, resolution_factor can be heuristically set.
+    # Let's try 0.05
+    grid_size = max_dim * 0.05
+    
+    v_idx = np.round((vertices - min_v) / grid_size).astype(np.int32)
+    _, unique_idx, inv_idx = np.unique(v_idx, axis=0, return_index=True, return_inverse=True)
+    
+    new_vertices = vertices[unique_idx]
+    faces = inv_idx.reshape(-1, 3)
+    
+    valid = (faces[:,0] != faces[:,1]) & (faces[:,1] != faces[:,2]) & (faces[:,0] != faces[:,2])
+    valid_faces = faces[valid]
+    
+    new_m = mesh.Mesh(np.zeros(valid_faces.shape[0], dtype=mesh.Mesh.dtype))
+    for i, f in enumerate(valid_faces):
+        for j in range(3):
+            new_m.vectors[i][j] = new_vertices[f[j]]
+    
+    new_m.update_normals()
+    new_m.save(output_path)
+