[Qgis-developer] Rejigging raster layer drawing
b.rowlingson at lancaster.ac.uk
Thu Apr 26 07:43:28 EDT 2007
I've been digging deep into the raster layer draw code, and it seems to
have a lot of cruft lying around. Exhibit A is the unused method,
QgsRasterLayer::drawPalettedSingleBandColor, which I guess is related to
the unused drawing style of 'PALETTED_COLOR' - these things are defined
but not referenced anywhere...
The pseudo-color stuff is a bit crocky too, with colouring techniques
hard coded into the draw methods. Pseudo-color just seems to be a
modification of the paletted drawing methods.
I think this code could all be simplified into a more unified set of
drawing methods, using user-defined colour palettes to produce colour or
grayscale renderings based on single or multi-layers, or using palettes
from the layer data itself, with optional scaling/stretching/clipping.
I am prepared to put some time into this since its a feature I dearly
want in QGis, in fact I pretty much need it for a current project, and
attempts to bodge it into shape have failed! What I think I need is some
help from the more competent to make sure my plans are good plans (and
not evil plans), and to see any other ramifications they may have - for
example it will probably imply changes to the 'properties' dialog in the
Qgis App code...
Anyone on board with this? I'd chat on #qgis but you lot are only there
at 3am my time!
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