|QGIS Colormap view|
QGIS (version 1.8 and before) lacks built in predefined colormaps . The only default possibility to create a colormap is to classify by equal intervals and with red-blue colors. While it is still possible to manually edit automatically created colormap, I found it completely unhandy. Firstly, because most of my raster data I would like to represent with certain step within chosen amplitude, secondly, I would like to represent the raster in different color scale and thirdly - I would like to use more color scales than one.
|Interface of my Colormapping tool. Two color |
scales used here - from black to white and from
white to green.
When someone creates the colormap for chosen raster, it is possible to save that custom colormap as a plain text file. That gives an opportunity to prepare such a text file outside of QGIS, no matter where and how. As my working environment is Windows and I know some Visual Basic stuff, I wrote a little helper program, where I am able to set start value, count of the categories, step of the value and combine or put together multiple colormap scales.
Important notice: the first and default color scale can be obtained pushing button "Classify". For other scales click right mouse button on a chosen category and menu will appear.
The program is written in Visual Basic 2010 and is dependent of Microsoft .NET 4 framework. It will not be able to run while that framework has not been installed.Short overview about program usage can be seen in following video.