The source code is presented next. Note that if the light is a directional light, the vector with the first three components is normalised to save time latter.

函数的源代码如下。注意如果光源是方向光，向量的前三个部分将被归一化，来节省时间。

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By regarding a linear light source as a directional rectangular light source with infinitesimal width, a simple formula is derived for calculating the diffuse reflection component.

通过将线光源看作一个具有无限细小宽度的有向长方形光源，我们得到了一个计算漫反射分量的简洁公式。

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This sphere serves as a diffuse light source, which enables measurements of the hemispherical reflectance, or the directional absorptance, respectively.

这个球作为扩散光源，使测量的半球形或定向吸收率的反射系数，分别使用。

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