File Tools | Toggle Buttons | Open Collection | Measure | Navigation Tools | Drawing Tools | Other Functions

File Tools

Open File

Open a raster or vector file, and add it to the current view as a new layer. The resulting layer will be assigned the name of the source file. Same as File->Open.



 Save the view state to a Project (*.opf) file. Same as File->Save Project As.


Save View As Image

Save the visible layers in a view to a file.


Print View

Launches the Printing Dialog for printing the view contents.




Toggle buttons

Layer Manager

Toggle the Layer Manager on/off for manipulating view layers.

Link Views Selecting Link Views will cause the view areas of all open windows to be linked. Pressing the button again will unlink the views. Any change of view in a linked window will result in all other windows also being updated similarly. View characteristics includes the view position, zoom level, and rotation in 2D. In 3D this includes the view position, view direction, and vertical exaggeration. View characters does not include details about layers displayed, layer colors or anything of that sort. Link windows will only operate correctly if all views are in the same coordinate system. For instance, if one view is georeferenced in UTM, and another is in lat/long degrees, the linked views will not operate in a useful manner.


Toggle this tool on, the use RightClick to 'flicker' the visibility of Image layers open in the active view. Note that more than one image must be open in the active view for the tool to work. Note also that the tool will only be effective if the images overlap.

Open Collection

Open Imagery Toggle on, then click inside the footprints of a Collection to open a dialog list of all available imagery, sorted by date and sensor. Note that this icon will only be visible after the user has opened a collection. More information on Working with Collections is provided seperately.




Measure Distance Use LeftButton-Click to start measuring distance between two/more points. Use RightButton-Click to terminate the session.

Measure Area Use LeftButton-Click to start measuring area enclosed by three/more points. Use RightButton-Click to terminate the session.



Navigation Tools

Re-center View

Toggle switch to re-center the view extents - a one-click pan. The toggle will be switched off if one of the editing tools is selected.

Dynamic Zoom

Dynamic Zoom mode offers some simplified view operations. LeftButton-DoubleClick will zoom the view by one increment (a factor of two), and re-center the view on the target location. Use RightButton-DoubleClick to zoom out by one increment (a factor of two). Use LeftButton-Drag to draw out a zoom rectangle, and zoom on release. LeftButton-Press and Hold will zoom in continuously, while RightButton-Press and Hold will zoom out continuously. If available, MiddleButton-Press and Drag will drag pan the image.

Zoom All

Click once to reset the view to include the extents of all open layers.

Zoom to Layer

Click to reset the view to the extents of the currently active layer.

Previous Zoom

Click to revert to the previous zoom state.

Zoom Factor Displays the zoom level of the currently selected raster layer. A value of 1:2 would indicate decimation by 2, while 2:1 would indicate duplication of raw pixels by a factor of two. The user can selected a desired zoom level from popup menu, or directly type in zoom ratios. The control has no effect when a non-raster layer is selected.



Drawing Tools

Drawing tools allow for the creation and manipulation of vectors. The tools operate on a single vector layer, which must be the active layer in the Layer Management Dialog. The tools will attempt to create a vector layer if none is available and will make one active if the active layer is not a vector layer. It is a common frustration to be unable to select or modify vectors because they are not in the active layer. Note that while not explicitly disabled in 3D mode the various editing interactions will generally not work properly in 3D mode. Also, note that essentially all editing operations can be undone by hitting Control-Z or selecting Edit->Undo in the menu.


Select mode allows selection of vector features, and limited manipulation of those features. Selected features are highlighted with small diamonds around the nodes. Selection may be accomplished in several ways: LeftButton-Click: Select the feature at the click location. Note that points and lines have only a modest tolerance for selection. Clicking inside a filled area will select the area. If more than one features overlaps the click location, only one will be selected (based on internal stacking order). LeftButton-Drag: Drags out a box and on release selects all features intersecting the box. Note that the box drag has to start at a location where there is no feature, otherwise it will be interpreted as a single selection, and the selected feature will be dragged instead of a box being drawn. Shift-LeftButton-Click: Operates like LeftButton-Click, but adds or removes the selected feature from the current selection instead of clearing the existing selection. In most editing systems this would be Control-LeftButton-Click, but that is already bound to continuous zoom. While in selection mode it is also possible to drag the selected features around by left clicking on a selected feature, and dragging. If multiple features are already selected, they are all dragged as a group. The Delete or Backspace key may be used to delete the currently selected feature(s). The help topic for most dialogs can be launched directly by hitting F1 after clicking on the dialog.

Draw Point

Point edit mode is for creation of point features. Each LeftButton-Click in the view will result in a new point feature being created, and after creation it will be the selected feature. The Delete key can be used to delete the currently selected point if there is one. It is not possible to move, or otherwise manipulate points in this mode. Switch to Select mode to do that.

Draw Line

Line edit mode is for digitizing new line features. Note that Select mode is used to modify existing lines, and Node edit mode is used to modify individual nodes within an existing line. Use LeftButton-Click to initiate digitizing of a new polyline. Subsequent left clicks will add new nodes to the polyline. The RightButton-Click or Escape key can be used to terminate line mode. While digitizing a line, the Delete key can be used to delete the last node added. Note that while digitizing a line undo support is temporarily disabled.
Draw Rectangle Rectangle drawing mode is for digitizing and modifying rectangular area features. LeftButton-Drag can be used to draw a new rectangle feature. If you click on the corner of an existing rectangle, that corner can be dragged, resizing the existing rectangle. If you click on the edge of an existing rectangle, that edge can be dragged resizing the existing rectangle. The Escape key can be used to abort creation of a new rectangle, but while dragging an edge or corner of an existing rectangle it will just stop the dragged, equivalent to releasing the button. 
Draw Area Area drawing mode is for digitizing area (polygon) features, which can contain holes. Moving existing areas is done with Select mode, and adding, removing or moving nodes in an existing polygon is done with Node Edit mode. Digitizing a new polygon is accomplished by LeftButton-Clicking at each vertex location. When complete a RightButton-Click terminates the process, and the polygon is closed. Adding an internal ring (a hole) to an existing polygon is done by digitizing a new polygon entirely within the old polygon. The nesting is recognized, and the new polygon is treated as an internal ring to the main polygon. Note that this implies it is impossible to digitize a separate polygon that is inside another polygon ... to accomplish this, digitize it elsewhere, and then drag it into the area. If you digitize an a new polygon that starts inside another polygon, but goes outside the parent, it will be discarded on termination as a corrupt hole.
Draw Ellipse/Circle Use RightButton-Click-Drag to draw a circle or ellipse on a shapes layer.
Draw Label Label mode is used to draw labels on a shapes layer. On selecting the tool, the cursor will change to a cross - LeftButton-Click the location in the View Area where the label is to appear. A dialog is shown, with buttons to customize color and font, and space where text for the label can be entered .

Other Functions

Refresh Raster Causes the current raster layer to be reloaded from disk. When working with collections, or in sessions that involve many views, the tool is useful to correct raster display if it appears blocky or patchy. Only applies to an active raster layer - if no raster layer is active nothing happens.
Help Launch the TerraLook online help, the same as Help->Help. Note that pressing the F1 key while using any TerraLook dialog will open the associated help file in a browser window.
Idle/Busy Indicator The red icon shows when the application is busy, and the green icon displays when the application is idle. Due to the background loading of data the application will often be busy for a short time after initially displaying a raster. Pressing the icon has no effect, and even when the application is busy it should remain responsive if somewhat more sluggish than when idle.