Rendering Cities using OSM

So lately I was feeling like getting back into messing around with some 3D “stuff”. I recently came across Vizicities and was inspired to do something similar myself. The basic Idea is to render a city (in this case) using open source data from Open Street Map. One of the reasons I really like working on visual things is I like to watching build up step by step from nothing. This project seemed ideal.

Choice of API/Programming Language

I have actually built something similar to this before using CSharp and monogame, and overlaid the building information over a digital terrain model so that the buildings follow the shape of the terrain. In this case however, as I spend most of my days at work creating programs in CSharp and using higher level API’s I decided to go in the opposite direction. For this project I will be purely using C/Objective-C and OpenGL. I enjoy the control that you get when using a lower level API, and also the feeling of having done so much all by yourself! To be honest I also miss writing in objective-C. Though I must admit – the fact that you have to pay to use the Xamarin licenses compared to building with Xcode for free was also a small deciding factor!

Getting Started

To start out with I simply used one of the template applications included with Xcode (iOS development IDE). The result of this is a couple of spinning cubes as shown below. I chose this route to save me from having to write the boiler plate code to initialise OpenGL.