Generating an environment on Linux to cross-compile QT applications for a Raspberry Pi running Debian Wheezy:
Grab tools (for the cross-compiler tool chain) and firmware (for the OpenGL libraries) from the Raspberry Pi GitHub repository:
git clone https://github.com/raspberrypi/tools.git --depth=1
git clone https://github.com/raspberrypi/firmware.git --depth=1
Copy OpenGL stuff to the toolchain's sysroot: