export_dxf.py 文件源码

def get_view_projection_matrix(context, settings):
    """
    Returns view projection matrix.
    Projection matrix is either identity if 3d export is selected or
    camera projection if a camera or view is selected.
    Currently only orthographic projection is used. (Subject to discussion).
    """
    cam = settings['projectionThrough']
    if cam is None:
        mw = mathutils.Matrix()
        mw.identity()
    elif cam in projectionMapping.keys():
        projection = mathutils.Matrix.OrthoProjection(projectionMapping[cam], 4)
        mw = projection
    else: # get camera with given name
        c = context.scene.objects[cam]
        mw = getCameraMatrix(c)
    return mw