How to draw terrain map from srtm3 data

[venky23]

Hi all,

I am new to Qt. I need to write a program to generate terrain map using SRTM3 data. I succeeded to read the elevation from srtm3. But, I have no idea how to plot it as terrain map with qwt. I know there exist some tools to do so, but I really want to have it in Qt

Any suggestions would really help me a lot.

Thanks in advance for your help

Regards
Venky

[ChrisW67]

I have no idea how to plot it as terrain map

How do you expect us to know how you would like to interpret and plot this data if you do not know/explain what your own requirements are. A hypsometric tinted flat map in native data coordinates, or with coordinates converted to some cartographic projection, whole world or small region, further smoothed or averaged, a wire mesh, a synthetic 3d terrain...? We cannot even tell you if Qwt is a good tool for your job.

[venky23]

Hi,

Thanks for your response. I have huge data set of x, y coordinates and corresponding height in z-axis.

Now I need able to project this data as a map like this example_plot.jpg.

Any suggestions ? Thanks for your help.

Regards
Venky

[ChrisW67]

A QwtPlot with a QwtPlotSpectrogram plot item to represent your height map.
A QwtRasterData subclass to interrogate and return the height at given x,y coordinates.
A QwtColorMap to determine the colouring based in the height value.

Once you have the basics you can worry about height legends and other fluff

[jesse_mark]

This seems really interesting, please if you implanted this do post an example of it.

best regards