Mayavi -以编程方式设置图像的[x,y,z]范围

Question

我有一些由几个2D图像组成的数据，我想使用mayavi2 (v4.3.0)在特定的[x,y,z]位置相互渲染。

从文档看来，我应该能够做到这一点与mlab.imshow()。不幸的是，mayavi抛出一个异常，当我调用imshow指定extent参数(AttributeError: 'ImageActor' object has no attribute 'actor')。

我还尝试通过修改im.mlab_source.x,y,z...直接设置x,y和z数据。奇怪的是，虽然这正确地改变了x和y范围，但它对z位置没有任何影响，即使im.mlab_source.z明显改变了。

下面是一个可运行的例子:

import numpy as np
from scipy.misc import lena
from mayavi import mlab
def normal_imshow(img=lena()):
    return mlab.imshow(img,colormap='gray') 
def set_extent(img=lena()):
    return mlab.imshow(img,extent=[0,100,0,100,50,50],colormap='cool')
def set_xyz(img=lena()):
    im = mlab.imshow(img,colormap='hot')    
    src = im.mlab_source
    print 'Old z :',src.z
    src.x = 100*(src.x - src.x.min())/(src.x.max() - src.x.min())
    src.y = 100*(src.y - src.y.min())/(src.x.max() - src.y.min())
    src.z[:] = 50
    print 'New z :',src.z
    return im
if __name__ == '__main__':
    # this works
    normal_imshow()
    # # this fails (AttributeError)
    # set_extent()
    # weirdly, this seems to work for the x and y axes, but does not change
    # the z-postion even though data.z does change
    set_xyz()

Answer 1

好的，原来这是mayavi中一个已知的bug。但是，可以在创建ImageActor对象后更改其方向、位置和比例:

obj = mlab.imshow(img)
obj.actor.orientation = [0, 0, 0]  # the required orientation 
obj.actor.position = [0, 0, 0]     # the required  position 
obj.actor.scale = [0, 0, 0]        # the required scale