Parallax Occlusion Mapping in augmented reality case study on facade of Sino Portuguese Architecture Phuket, Thailand

Sino Portuguese Architecture is a unique building in Thailand which combines with style of Chinese and European construction built around A.D.1890-1920. There are many details of bas-relief on the facade of the building. Currently, some of them have been destroyed or changed by the time. To preserve the buildings, which are houses, the digital data was established to collect the information of the houses and create to 3D virtual building represented by Augmented Reality (AR) technology. Using Augmented Reality with handheld devices is very popular because most people, nowadays, have smart phone or mobile phone. Thus, they can see the 3D houses via their handheld devices' camera and observe the building interacting with perspective changing in real-time. Therefore, the observers are able to view around the details of the virtual building easily. However, because of real-time interaction, handheld device have to render the visualization image as fast as changing point of view. Particularly, 3D model with many details, it takes load for handheld device computational time in case there are many details in 3D AR content because it cannot respond to the user simultaneously. This paper applies Parallax Occlusion Mapping (POM), which is well known technique for fast rendering of geometric detail and reducing a geometric complexity of model using surface detail information in a texture encoded, to 3D model of Sino Portuguese Architecture, which consists of many bas-relief patterns on the facade, in order to reduce the number of polygons. The system uses game engine, Unity3D, and Vuforia SDK implemented augmented reality application on handheld device. The result of this research use 1 polygon/ 1 bas-relief and the quality of visualization is compatible to each other on AR application.