import open3d as o3d
import os

def load_ply(file_path):
    """Carrega um arquivo PLY usando open3d."""
    mesh = o3d.io.read_triangle_mesh(file_path)
    return mesh

def simplify_mesh(mesh, reduction_factor=0.5):
    """Reduz o número de triângulos da malha."""
    target_number_of_triangles = int(len(mesh.triangles) * reduction_factor)
    simplified_mesh = mesh.simplify_quadric_decimation(target_number_of_triangles)
    return simplified_mesh

def save_obj_with_mtl(mesh, obj_path, mtl_path):
    """Salva a malha em formato OBJ com MTL."""
    # Salvar o arquivo OBJ
    o3d.io.write_triangle_mesh(obj_path, mesh)
    
    # Gerar o arquivo MTL
    with open(mtl_path, 'w') as mtl_file:
        mtl_file.write("newmtl material_0\n")
        mtl_file.write("Ka 1.000 1.000 1.000\n")
        mtl_file.write("Kd 0.800 0.800 0.800\n")
        mtl_file.write("Ks 0.000 0.000 0.000\n")
        mtl_file.write("d 1.0\n")
        mtl_file.write("illum 2\n")

def convert_ply_to_obj(ply_path, obj_path, reduction_factor=0.5):
    """Converte PLY para OBJ com redução de triângulos e gera arquivo MTL."""
    mesh = load_ply(ply_path)
    simplified_mesh = simplify_mesh(mesh, reduction_factor)
    
    # Definir o caminho do arquivo MTL
    mtl_path = os.path.splitext(obj_path)[0] + ".mtl"
    
    # Salvar o OBJ e o MTL
    save_obj_with_mtl(simplified_mesh, obj_path, mtl_path)

# Caminhos dos arquivos
ply_file = 'montagem_pulverizador.ply'
obj_file = 'montagem_pulverizador_0.03.obj'

# Converter e simplificar
convert_ply_to_obj(ply_file, obj_file, reduction_factor=0.03)