<p>I'am studying PBR and the book introduce the potential equation.
They said the potential equation can describe shooting algorithms better, and
$W(x, \theta)$ describes the fraction of the radiance $L(x, \theta)$</p>

<p>But I could not understand the concept. </p>

<p>Is just $W(x, \theta)$ a fraction such as $\frac{1}{3}$(I know the original equation is quite complicate, integral) to reduce the radiance $L$ which is derived from a light source? (because the L would be diminished if it collides with objects).</p>

CC BY-SA 3.0
2017-06-20T13:34:06.133Z
Can you give a chapter or page number where $W(x,\theta) $ is described in PBR?
user81327
CC BY-SA 3.0
2017-06-21T07:38:58.917Z
I'am using a book 'Advanced Global Illumination 2ed' (page 89 chapter 4.2)  and referring to "dspace5.zcu.cz/bitstream/11025/15417/1/Willems_94.pdf" (page 4, 5 the potential equation)
shashack
<physically-based><pbr><photo-realistic><realistic>
What is the potential equation in PBR?
shashack
# What is the potential equation in PBR?

(Asked by: username_0 on 2017-06-17)

I'am studying PBR and the book introduce the potential equation.
They said the potential equation can describe shooting algorithms better, and
$W(x, \theta)$ describes the fraction of the radiance $L(x, \theta)$

But I could not understand the concept.

Is just $W(x, \theta)$ a fraction such as $\frac{1}{3}$(I know the original equation is quite complicate, integral) to reduce the radiance $L$ which is derived from a light source? (because the L would be diminished if it collides with objects).

**Tags:** physically-based, pbr, photo-realistic, realistic

> **Comments:**
> **username_1**: Can you give a chapter or page number where $W(x,\theta) $ is described in PBR?  
> **username_0**: I'am using a book 'Advanced Global Illumination 2ed' (page 89 chapter 4.2)  and referring to "dspace5.zcu.cz/bitstream/11025/15417/1/Willems_94.pdf" (page 4, 5 the potential equation)  

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## 0 answers

