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libnoise viewer

12 Jan 2010

#motivation

i’ve just fixed most bugs in libnoise-viewer [1] and the software is really usable now. it features a QGraphicsScene and a QGraphicsView and to make it faster i’ve used some it::blackmagic called threads. Actually i used QThread and this was my first real use of multi-threading and it works pretty well. When i scroll the planar area small tiles are generated, two at a time are dispatched so that a dual core system is ‘saturated’ cpu load wise.

This viewer uses the ‘noise::module::RidgedMulti’ module to generate the surface in a black/white fashion. All i did was to apply a color-band according to the relative height. As you might have seen already, there is a black/white vs color toggle. Using this you can visualize the heightmap.

if (job.colorstate) {
renderer.ClearGradient ();

renderer.AddGradientPoint ( 1.000000, utils::Color (0, 90, 0, 255));
renderer.AddGradientPoint ( 0.740000, utils::Color (0, 129, 0, 255));
renderer.AddGradientPoint ( 0.700000, utils::Color (0, 190, 0, 255));
renderer.AddGradientPoint ( 0.650000, utils::Color (0, 250, 0, 255));
renderer.AddGradientPoint ( 0.600000, utils::Color (120, 250, 250, 255));
renderer.AddGradientPoint ( 0.390000, utils::Color (20, 120, 200, 255));
renderer.AddGradientPoint ( 0.340000, utils::Color (20, 50, 250, 255));
renderer.AddGradientPoint ( 0.200000, utils::Color (0, 0, 120, 255));

renderer.EnableLight();
renderer.SetLightContrast (3.0); // Triple the contrast
renderer.SetLightBrightness (2.0); // Double the brightness
}

The rendering speed is very good. But see yourself (the upload of the ogv video to wordpress media didn’t work, so i host it somewhere else).