uniDEM supports drawing of a selection over loaded geospatial data (DEM, images) so that operations can be performed on the selected area.
Selections are made by holding the shift key and left mouse button concurrently.
The simplest of selections is the "Select All" feature (Ctrl-A) which will select all pixels of the Active dataset.
Draw a rectangle that can be subsequently used to select or modify a selection. The rectangle is projected onto the raster independent of heading.
It is created by holding shift and left button on mouse while drawing. Erroneous rectangle can be removed with esc.
Default shortcut: r
Draw a polygon that can be subsequently used to select or modify a selection. The polygon is projected onto the raster independent of heading.
Polygon points are collected by holding shift and then left clicking. The polygon is closed with each point addition.
Erroneous points added to the polygon during collection can be removed with shift and backspace.
Default shortcut: p
Draw a line that can be subsequently used to select or modify a selection. The line is projected on the raster over its length and orthogonally out to the width defined in Line Width in Drawing Options.
Erroneous points added to the line during collection can be removed with shift + backspace.
Default shortcut: l
Select a pixel by drawing a dot. Toggles the selection of a single pixel to selected or deselected for detailed edits.
Default shortcut: e
The flood fill tool is used to select areas similar to the first selected pixel of the layer being filled upon.
Filling is started with shift then left click over the seed pixel.
See Fill Options for a description of filling parameters.
Default shortcut: f
Manipulate graphs, shapes or other vector data which can be used to flatten features like doulble line drains (DLDs) and roads.
Default shortcut: q
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