Display large DEM with MaxPlotPoints

MaxPlotPoints is a very useful option when works with large DEM.

dem=Import[tif,{"GeoTIFF","Data"}];
Dimensions[dem]
{2825, 5075}

Try ReliefPlot[dem], it takes a very long processing time in my not-up-to-date computer, on the other hand, with limited monitor resolutions, it doesn’t make sense to draw every point of this DEM.

Let’s first try:

ReliefPlot[dem, MaxPlotPoints –> 25]

 

Not quite good, the pixel is in rectangle shape rather than square, then with the small adjustment:

ReliefPlot[dem, MaxPlotPoints -> {50, 25}]

 

ReliefPlot[dem, MaxPlotPoints -> {1000, 500},
ColorFunction -> "GreenBrownTerrain"]

Click to see the large image, please ignore the left part, it is a quality issue from the DEM data source.

The same rule goes with ListPlot3D, if you want to get a 3D version.

ListPlot3D[dem, MaxPlotPoints -> {600, 300}, Mesh -> None,
Axes -> None, ColorFunction -> "GreenBrownTerrain",
BoxRatios -> {2, 1, 0.2}, ImageSize -> 1200]