Based on the combination of TFT module and Arduino UNO fram Banggood and the GPS module from the same supplier I built a basic GPS navigation system that uses the topographical maps of The Netherlands (top25raster). In total there are 304 bmp files on an SD card, so the images are very detailed! In principle any 8 bit bmp map can be used. The maps were obtained from www.kadaster.nl, the software is based upon modules from Adafruit. Sketch plus explanation are available on Github: middelbh/GPSnavigator. Enjoy and please inform me about optimisations!
I now have the software completely running! The next step is to connect the GPS module and do some tests.
I hope someone can help me in further optimizing the sketch, it's about 99% of the maximum size for my UNO, and displaying the map still takes 1-2 seconds. That must be faster I think. I am a relative beginner with Arduino, so any help is greatly appreciated!
Other question is, where shall I put the source of the sketch??