New tool: Ability to draw a region (computation range) from the map display module

[vesnikos]

The ability to mark the computational range to perform revelant algorithms in only parts of the map im intrested of will really help speed up my workflow.

At the momment there is the option to set the region from current display extents (through the zoom option button), but there is not any way to visualy mark the region I am intrested in by drawing a rectangle (to get the extents) for example.

You can also set the region manually with g.region but its prone to human error (you can easily miss a digit)

[hamish]

see also qgis-grass toolbox where a red bordered box is used to show the computational region, and the d.region.box addon (just shows another region).

take care to align the ew,ns resolution if doing this, but if multiple rasters (or no rasters) are present, which to take it from? or preserve current computational region's resolution?

Hamish

ps- if you created or commented on a ticket you're automatically added to the cc list

[vesnikos]

Hey Hamish,

Yeah, I know about that module but im not sure if you can specify the region.

Usually I identify visually a spot in my raster where a certain algorithm needs to be run. mostly holes that need to be filled with r.fillnulls. So I don't need it for the hole raster. Just for that spot. So preserving the raster's resolution makes sense. Plus its trivial to change it the res flag of 'g.region'.

If you have to do that more than three times, its too time consuming to querry the edges, and then plug them in g.region

What I had in mind is more like a functionality like the 'zoomIn' button, but instead of zooming in, it should change the computational extents of the rectangle you draw.

Nikos

[wenzeslaus]

Can you please test and comment on Set computational region extent interactively available in Map Display window under Various zoom options? If this is what you want, please close the ticket. (Martin implemented this feature some time ago.)

[wenzeslaus]

Closing as fixed. Available in but trunk and release branch 70. Tested in both.

Possible improvement is switching on Show computational extent automatically or writing g.region -p to command console (and history file) but these are separate requests which need more feedback.