qgis/Quantum-GIS — pull request #180 by etiennesky (2012-06-18 19:49:04+00:00)
Title: Histogram improvements

These patches improve the histogram and fix a few issues introduced with the resampler branch

bc12ef0d	fix histo tab number and Gray band name

Histogram was no longer updated, and the first band of a multi-band file (e.g. tests/testdata/landsat.tif) always appeared as "Grey"

8b9df648	add UI to pick min/max band values in histogram

This adds a number of UI elements in the histogram tab to choose the min/max values for each band, both in a linedit and also using a picker. Also a few actions that deal with loading the extent. Added access functions to QgsRasterRendererWidget to get/set min/max values and computing extents.

983591ee	add histogram zoom in/out

Zooming in can be accomplished by click-dragging the desired area, and zoom reset with right click.

85150725	verify that raster has cached histogram, compute on demand

Histogram is plotted only if it is cached - this requires a new function hasCachedHistogram() for raster layer and raster provider(default returns false). Gdal provider uses existing function GDALGetDefaultHistogram, other providers (GRASS) should be adjusted if there is a way to cache the histogram.

This has been discussed at http://lists.osgeo.org/pipermail/qgis-developer/2012-May/019963.html

c85d4e8d	prevent double refresh of histogram tab (#4132)