基於物理繪圖(Physically Based Rendering)是近年來十分熱門繪圖概念，有別於傳統的上色模型，從物質本身和周遭環境以真實物理的方式去計算光線，如此不但能夠畫出更真實的影像，也方便美術人員可以使用真實物理材質的參數來創作物件。由於參數的算法都是從真實物理的角度出發，擺設場景的時候不太需要去微調數據，只管放置物件，得到的影像也會十分真實。
在即時繪圖領域，需要使用許多的技巧才能簡化這些計算過程，如何去簡化繪圖方程式(Render Equation)才可以快速又不失真，有許多問題需要考量。於此我們將呈現一種即時繪圖的方式，使用和遊戲引擎相同的貼圖和環境光源來繪製場景，並且接入虛擬實境裝置中，實現即時而又逼真的場景繪製。

Physically Based Rendering became the most popular rendering techniques recently. Comparing with the traditional shading theory, it is more or less based on the same underlying theory which more closely matches to the physical world. Not only render the more photo-realistic image, but also help the artist design based on material’s physical attributes. Because the method is based on physics, it’s not necessary to tweak some specific parameter for building a scene, we can still get the correct results.
There are lots of hacking methods for real-time rendering. The key point is how to simplify the render equation and still get the acceptable lighting and shading. In this thesis, we introduce an method that using the same type of texture as game engine, we also implement using the environment texture as image-based lighting. And then render the results in virtual reality device.

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