This paper presents a new method of drawing perspective shade and shadow in parallel rays, which makes use of plane trace and geometrical drawing method.

探讨了一种利用平面迹线和几何作图法，作无灭光线下透视阴影的新方法。

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Then geometrical transformation matrix between views is obtained based on perspective projection model for X-ray angiography system, and 3D coordinate of spatial points are calculated.

然后根据冠脉造影系统的透视投影模型得到两幅不同角度的造影图像之间的几何变换关系，以及空间点三维坐标的计算方法。

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