blender_utils.py

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#  This program is free software; you can redistribute it and/or
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# <pep8 compliant>

import bpy

def faces_from_mesh(ob, apply_modifier=False, triangulate=True):
    '''
    From an object, return a generator over a list of faces.

    Each faces is a list of his vertexes. Each vertex is a tuple of
    his coordinate.

    apply_modifier
        Apply the preview modifier to the returned liste

    triangulate
        Split the quad into two triangles
    '''

    # get the modifiers
    try:
        mesh = ob.to_mesh(bpy.context.scene, apply_modifier, "PREVIEW")
    except RuntimeError:
        raise StopIteration

    mesh.transform(ob.matrix_world)

    if triangulate:
        # From a list of faces, return the face triangulated if needed.
        def iter_face_index():
            for face in mesh.faces:
                vertices = face.vertices[:]
                if len(vertices) == 4:
                    yield vertices[0], vertices[1], vertices[2]
                    yield vertices[2], vertices[3], vertices[0]
                else:
                    yield vertices
    else:
        def iter_face_index():
            for face in mesh.faces:
                yield face.vertices[:]

    vertices = mesh.vertices

    for indexes in iter_face_index():
        yield [vertices[index].co.copy() for index in indexes]

    bpy.data.meshes.remove(mesh)


def vertices_from_mesh(ob):
    '''
    '''

    # get the modifiers
    try:
        mesh = ob.to_mesh(bpy.context.scene, False, "PREVIEW")
    except RuntimeError:
        raise StopIteration

    matrix = ob.matrix_world.copy()
    
    for v in mesh.vertices:
        yield (matrix*v.co)

    bpy.data.meshes.remove(mesh)

def edges_from_mesh(ob):
    '''
    '''

    # get the modifiers
    try:
        mesh = ob.to_mesh(bpy.context.scene, False, "PREVIEW")
    except RuntimeError:
        raise StopIteration

    for e in mesh.edges:
        yield list(e.vertices)

    bpy.data.meshes.remove(mesh)