[Qgis-developer] Raster file creation using the QGIS API and Raster format for Heatmaps

[aruntheguy at gmail.com]

Hello all,

I am working on a heatmap plugin, which would generate a heatmap based on
the occurrence of points and their proximity. The present Interpolation
methods available in the QGIS API are for the attribute data or value
interpolation. Hence they are well off with the available GridFileWriter,
which computes the value at each pixel and writes out the value. But
Frequency heatmaps, would be better done, by computing the pixel which each
vertex/point represents and writing to that pixel. i.e., it is exactly the
reverse of what GridFileWriter does. I have tried implementing some
rudimentary logics by creating a QgsFrequencyInterpolator to use the
GridFileWriter itself, but the results are too far away from a  faithful
heatmap.

Hence I would like to know *how else* can a raster be created in QGIS using
the API?

Moreover the ASCII file format is too costly, in terms of memory, for a
heatmap which generally has a lot of null value entries, unlike other
interpolated rasters. In most cases, null values exceed the pixel
representations on the raster.

Hence which would be more appropriate format to represent a Heatmaps?

-- 
Regards
Arunmozhi
Twitter: @tecoholic
Website: http://arunmozhi.in
IRC Nick: teco
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