Many operations in Manifold begin by selecting something and applying an effect to that something.


The "something" might be a region of pixels in an image, a particular group of lines in a drawing or some special selection of records in a database table.


The "effect" could be an operation that transforms what’s in the selection, such as brightening only those pixels selected in an image or it could be a request to analyze what’s in the selection and make a report. For example, we might select a group of records in a database table and ask what the average is of the "Population" field for those records.


Choosing that "something" on which we wish to work is making a selection. There are two key ideas connected to selections in Manifold:


·      Making a Selection - Use the mouse to point at something or to drag open a rectangular, circular or free-form box to select everything inside the box. Selection Tools let us do this. We can also make selections with the transform toolbar, with scripts, using the Query toolbar or from SQL.

·      Changing the Selection - After we’ve made a selection we may want to add to it, subtract from it or otherwise change it. This is what selection modes and selection commands help us do.


The examples below are illustrated using images. The concepts and methods they show work with drawings as well. To follow along, use File - Import - Image to import the bronze.jpg sample image into the project. Double-click on the bronze image component to open it in an image window. The bronze.jpg image may be found in the Manifold examples downloads.


Note: Selection can only be done in components that are read/write. Selection is not supported in images or drawings that are read-only. For example, Compressed images are a special type of read-only image that may be displayed but not otherwise manipulated. Compressed images do not support selection.


Making a Selection




1. Choose the selection tool. We’ve picked the Select Box rectangular box selection tool.




2. Make the selection by clicking and dragging open a box with the mouse.




3. The selected pixels will be shown in red selection color.


Note: we can change the display style used to show the selected region so that the red crosshatch pattern does not get in the way of graphics editing. This is discussed further down in this topic.




Other tools allow making the selection in different ways. In the image above we’ve used Select Touch to click on the blue sky and thus selected all blue pixels within the touch selection’s tolerance. Following is the full set of mouse selection tools available in Manifold:



Select Touch - Click to select pixels like the one clicked, give or take the tolerance that may be set in the Tool Properties pane. See the following note on touch selection in surfaces.


Select Shape - Left click to draw a closed shape and right click to end and select all pixels within the shape.


Select Freeform - Select objects within the mouse cursor region defined by clicking and dragging, followed by a right click.


Select Box - Click and drag to select items within a rectangular selection box


Select Box on Center - Click and drag open a selection box that’s always centered on the point of first click.


Select Circle - Click and drag open a selection circle within the rectangle implied by the mouse motion.


Select Circle on Center - Click and drag open a selection circle that’s always centered on the point of first click.


Select Ellipse - Click and drag open a selection ellipse within the rectangle implied by the mouse motion.


Select Ellipse on Center - Click and drag open a selection ellipse that’s always centered on the point of first click.


Shifts selection to "open" mode. In drawings, selects all items any part of which is within the shape drawn with the mouse.

In images (using Select Touch) the SHIFT key will apply the touch select to all pixels like that one touched even if they are not contiguous.


Touch Selection


Touch selection in drawings will select the objects touched. In images and surfaces, touch selection will select pixels within the tolerance setting in the Tool Properties pane. We can also select ranges of elevations in surfaces using the transform toolbar. See the Editing a Surface for Visual Effect topic for an example.


Regular and On-Center Commands


Note that some commands, like Select Circle, also occur in an "on-center" version such as Select Circle on Center.


Like selection tools, painting tools occur in both on-center and regular versions. We can see the difference between the regular tool and the on-center tool by painting a circle. Painting tools are used in these illustrations with tool opacity of 50 (half-transparent painting) to better show the difference in operation between regular and on-center commands.


images\img_tools_alt_key_01.gif images\img_tools_alt_key_02.gif


images\btn_paint_circle.gif Using Paint Circle to click near the center of the monument above and then dragging to the spot shown will open a preview circle as shown. Releasing the mouse button paints within the indicated preview circle. With regular commands, the mouse shows the desired diameter of the circle.


images\img_tools_alt_key_03.gif images\img_tools_alt_key_04.gif


images\btn_paint_circle_center.gif We can use Paint Circle on Center to click at the same beginning location and then drag to the same ending location. Note that the preview circle is larger than the previous circle. With on-center versions of commands the initial click is the center of the circle and the mouse motion shows the desired radius of the circle.


Select Objects Buttons


Select objects buttons allow us to specify what types of objects are selectable. This is very useful when working with complex maps with lots of objects in sight, because it allows us to enable selections only for certain items, such as pixels. These buttons work like filters: what's pushed in is allowed and what is not pushed in is not.




Choose the type of items that are to be selected by pushing the selection filter buttons for the desired types. The buttons above show selection enabled for points and disabled for areas, lines and pixels. If we drew a selection rectangle over a region in the map that contained all four types of items, only the points within the rectangle will be selected. Areas, lines and pixels within the rectangle will be ignored.



Select Areas - Enable selection of areas by mouse selection tools.


Select Lines - Enable selection of lines by mouse selection tools.


Select Points - Enable selection of points by mouse selection tools.


Select Pixels - Enable selection of pixels by mouse selection tools.


Select Text - Enable selection of text labels by mouse selection tools.


All five filter buttons will be displayed and may be used in maps. When working in drawing windows, the Select Pixels and Select Text buttons will not be visible since there are no pixels or text labels in drawing windows. When working within image windows, there are no select objects buttons displayed since images consist only of pixels. In images, selection of pixels is always enabled.


Selection Modes




The selection mode buttons control how a new selection made with a selection tool is combined with any existing selection. One selection mode button is always pushed in.




Select Replace - Replace the existing selection with whatever is now selected.


Select Add - Add whatever is now selected to the existing selection.


Select Subtract - Subtract whatever is now selected from the existing selection.


Select Invert - Deselect whatever is now selected that was already in the existing selection and otherwise add what has just been selected.


Select Intersect - Select only the region of overlap between what is specified by the tool and what is in the existing selection. If there is no overlap, nothing will be selected.


The default is Select Replace, where any new selection replaces the previous one.


images\tselect_1.gif images\tselect_3.gif images\tselect_4.gif images\tselect_2.gif


With Select Replace on, if we click several times using Select Touch we would get a new, different selection each time depending on where we clicked.


images\selmodes_1add.gif images\selmodes_2add.gif images\selmodes_3add.gif images\selmodes_4add.gif


If we use Select Add we increase the selection every time we touch a different region of like-colored pixels.


Let’s look at a series of examples to illustrate the other modes. In each case we will start with a selected region (made with Select Touch between the horse’s legs. A dark circle has been added to show clearly the selection circle drawn with the mouse.




We will then choose a selection mode and use Select Circle in a new selection to see what happens:










With Select Replace, the circle replaces the previous selection.










With Select Add the circle is added to the previous selection.










Select Subtract removes the part of the previous selection that was overlapped by the circle.










Invert Selection takes any part of the circle that overlaps the previous selection and removes it from the selection and otherwise adds the circle. If all the pixels in the bronze statue were selected and we wanted to deselect that and instead select all pixels not in the statue, we could use invert selection and draw a rectangular selection box that covered the entire image.










Select Intersect takes the intersection of the circle and the previous selection. Select Intersect is very handy when using different combinations of selection tools and selection modes.


The Selections Pane


Once we pick out a selection, we can save it in the Selections pane . We can then re-use it or recombine it with an existing selection using the Selection Commands. The Selections pane may be popped open from the View - Panes menu. It is often left open and docked into the main Manifold window together with other control and information panes.


Saving a Selection


1. Choose View - Panes - Selections to open the Selections pane.

2. Make a selection.

3. In the Selections pane, click images\btn_newsavedsel.gif New to save the selection into the list in the dialog.

4. If you don’t like names like "Selection1" and "Selection2" double click onto the selection’s name and change the name.


Shortcuts: Open the Selections pane with ALT- SHIFT- S. Close it with another ALT- SHIFT- S or click onto the x Close button in the upper right hand corner of the pane.


The selection pane is very important when working with the transform toolbar . Saved selections can appear in either the target box or the parameter box.


Selections Pane Examples


In the examples that follow, we have used the above steps to save three selections that we have renamed to be called "Sky", "Clouds" and "Box."




We can build up the selections quickly by using Select Touch in Select Add mode. We could click on different parts of the blue sky, for example, to add all the different blue regions quickly to one selection that we saved as Sky.













Once the above selections have been saved into the Selections pane we can retrieve them at any time.


images\btn_preview.gif To see what a saved selection looks like without actually using it, press in the Preview button in the Selections pane. The saved selection will be shown in the drawing window using a blue hatched pattern in addition to any selection that may already be there:




The image above is what the Clouds saved selection looks like as a preview.




This image shows the Box saved selection as a preview.


Selection Commands




Five selection command buttons are arrayed at the top of the Selections pane. These commands apply to whatever saved selection has been highlighted in the dialog. If we click on a saved selection to highlight it and then press one of these buttons, it will be combined with whatever is the current selection in the image. The selection commands allow us to use the saved selection to replace the selection, to add to the selection, to subtract from the selection, to invert with the selection and to intersect the selection.



Select Replace - Replace the existing selection with the highlighted saved selection.


Select Add - Add the highlighted saved selection to the existing selection.


Select Subtract - Subtract the highlighted saved selection from the existing selection.


Select Invert - Deselect what is in the highlighted saved selection that was already in the existing selection and otherwise add the highlighted saved selection.


Select Intersect - Select only the region of overlap between the highlighted saved selection and what is in the existing selection. If there is no overlap, nothing will be selected.


images\btn_selcmd_rep.gif For example, if we click on the Clouds saved selection to highlight it and then press Select Replace, the Clouds selection will replace whatever was the previous selection:




This is a common method of retrieving a saved selection: simply click on it in the Selections pane and then press Select Replace.


We can also use the selection commands to combine the saved selection with whatever is the current selection in the image. In the examples that follow, we have first made the Clouds selection and then we have highlighted the Box selection which is shown in the preview blue color. After that, we click on one of the selection mode commands to see what happens:










Select Replace - The pixels in the saved Box selection are selected and all others are deselected.










Select Add - The pixels in the saved Box selection are added to those already selected Note how the legs of the horse were not selected before and are not selected after the Add operation. Pretty neat, isn’t it?










Select Subtract - The pixels in the saved Box selection are subtracted from the existing selection. Note how the new selection has had the region of overlap removed.










Select Invert - Any pixels in the region of overlap are deselected while all those that are in the box or in the previous selection are selected.










Select Intersect - Select all pixels in the region of overlap between the Box and the previous selection. If there is no overlap, no pixels will be selected.


Example: Selection Tools, Selection Modes and Saved Selections


This example shows various selection capabilities used in combination.




images\btn_selmod_add.gif Using Select Touch and Select Add we click on different parts of the image to add pixels to the selection as desired. If we "overshoot" and add some pixels we don’t want, we use Select Subtract with a convenient tool such as Select Rectangle to remove the undesired pixels from the selection.




images\btn_selmod_int.gif Next, using Select Intersect we use Select Circle to grab only those previously selected pixels that fall within the circle. We can save this selection into the Selections pane.




When a selection is made in an image, editing effects apply only to those pixels selected. Here, we’ve used Hue / Saturation to change the hue of the selected pixels.


images\btn_deselect.gif We then clicked Deselect to deselect all pixels. Nice, but not bright enough…..





Using the Selections pane, we can recall the selection we used previously. When shown as a preview the saved selection is drawn in bright blue color. We are happy we saved it, since we want to change the saturation and lightness of exactly those pixels that were in this selection earlier. We press Select Replace to use this saved selection in the image.




We’ve used Hue / Saturation to increase the saturation and lightness of the selected pixels and then clicked Deselect once more to get rid of the selection hatch pattern. That’s better!


If the Selection Pattern Interferes


A dense red grid shows the selection well without any ambiguity; however, it can obscure the effect of changes that are applied to the selected pixels. There are two ways to deal with this:


images\btn_selstylarrow.gif Change the selection style to a less intrusive pattern or color or other style. The pull-down arrow next to the Use Selection Color button opens a menu of possible selection styles, including simple border and various pattern densities.


images\img_selstyle_default.gif images\img_selstyle_border.gif


images\btn_selstyle.gif Toggle the Selection Style button. This button turns the selection style ON and OFF. When OFF, the selected pixels are still selected but no red crosshatch pattern will be shown. When ON the red selection pattern will appear over the selected pixels. When making changes such as hue and brightness changes it is often quite obvious which pixels are selected by the changes being applied.


Try making a selection and then toggling the Selection Style button to turn off use of the selection pattern. The pixels are still selected but there is no pattern showing. We can then apply effects with a preview box checked and see the results directly within the image.




If we begin with a circular area of pixels selected we might wish to see the effects of lightness changes without visual interference from any selection style, so we toggle the Selection Style button.


images\seloff_eg0.gif images\seloff_eg2.gif images\seloff_eg3.gif images\seloff_eg4.gif


At first we see nothing, since the selection style pattern is gone. However, the changing visual appearance on moving the lightness slider control in the Hue / Saturation effect makes it easy to see which pixels are affected.


Selection in Drawings


The examples above use images because it’s easy to see what is going on with selection in images. The same techniques will work throughout Manifold System with drawings, tables, charts and connections between them. For example, selections can be made and saved into the Selections pane for drawings as well as for images.


In almost all cases, every window in Manifold that shows data will have selection tools for mouse selection, the cumulative action of which will be controlled by selection modes.



Suppose we have a drawing of the United States. We can use Touch Select together with Select Add mode to click on states to add them to the selection…



First we click on California.



Next we click on Utah.






… and finally, Nevada. We can save this selection above as a saved selection in the Selections pane for the drawing.



Let's call this saved selection South West States



We can then make another selection in the drawing.



If we like, we can save this new selection in the Selections pane as well. We will call this new saved selection Mountain West.



At any time we can now click on either of the two saved selections in the Selections pane and, with the Preview button pushed in see them previewed in the drawing.



For example, previewing the South West States saved selection will show it in the drawing in blue preview color.


Saved Selections and the Transform Toolbar


Saved selections will appear in transform toolbar boxes that can work with selection sets. For example, if a drawing has two saved selections called South West States and Mountain West then these will appear as choices in the transform toolbar when that drawing has the focus.


When drawings appear together in a map, if any drawing layer has the focus the transform toolbar for the map will list all saved selections in all drawings. This is a great convenience, but it also leads to a slight complication in that all saved selections using the same name are treated alike. Saved selections in the same drawing are required to have different names, but saved selections in different drawings might use the same name.


The transform toolbar for the map will treat all drawing saved selections using the same name as one, combined saved selection. For example, if we have two drawing layers in a map, one called East and the other called West and they both have a saved selection called Cities, then using the transform toolbar to create a convex hull using the saved selection choice called Cities will use the objects from both the East and West drawings that appear in their respective Cities saved selection.


Therefore, it is a good idea to use unique names for saved selections in drawings that might appear together in the same map. For example, we could name the saved selection in one drawing East - Cities and that in the other drawing West - Cities.


Selection by Type


The Edit menu for drawings includes a Select by Type choice. Use this command to select all of one or more types of objects, that is, all areas, lines or points in the drawing. The Select by Type command applies whatever Selection Objects and Selection Modes settings are in force.


images\btn_selfilter_points.gif images\btn_selmod_rep.gif For example, to select all of the points in a drawing we would push in the Select Points button and the Select Replace button and then choose Edit - Select by Type. All points in the drawing will be selected, replacing any previous selection.


images\btn_selmod_add.gif If we simply wanted to add all the points to the current selection we would have pushed in the Select Add mode button and then chosen Edit - Select by Type.


CTRL-T is a keyboard shortcut to select by type. Other handy shortcuts are CTRL-A to select all and CTRL-I to invert the selection.


Smart Mouse Selection


Smart Mouse selection is used to select objects for editing. An object selected with smart mouse selection will appear with edit handles that can be used to move or reshape the object. An object chosen for editing is also called the primary selected object.


Commands involving the mouse are normally controlled by whatever toolbar button is engaged. To use Select Box for example, we push the Select Box button in and then use the mouse in this mode. To provide fast operations when the mouse is not engaged in any other command, Manifold allows "smart mouse" selection in a way that mimics ordinary Windows point and click mouse highlighting and motion methodology as is used in Word and other applications.


images\sc_smart_edit_01.gif images\sc_smart_edit_02.gif


For example, CTRL-ALT clicking on an area object in a drawing will select it for editing. See the Editing Objects topic for examples and more information on interactive editing with smart mouse selection.


Keyboard Modifiers with Smart Mouse Touch Selection


Because a selection may already exist in the drawing when we wish to select an object for editing, smart mouse selection uses keyboard modifiers to allow a richer set of commands.



Equivalent to Select Touch in Replace mode.

Clicking into an empty part of the drawing deselects all objects.


Select the object as the primary selected object, that is, select it for editing. Does not change the selection state of other objects.

CTRL Click

Invert the selection state of the object without changing the selection state of any other object. Equivalent to Invert mode.


Select the object if it is not yet selected. Does not change the selection state of other objects. Equivalent to Add mode.


Smart Mouse Box Selection


When clicked on an empty region and dragged the mouse automatically makes a box selection analogous to using the Select Box selection tool in Select Replace mode. This is a general shortcut for selection. To select an object as the primary selected object for editing, CTRL-ALT click on it.


Keyboard Modifiers with Smart Mouse Box Selection


The following keyboard modifiers may be used with smart mouse box selection:


Click and drag

Click on an empty region and drag to make a box selection in Select Replace mode. Selects all objects that are entirely within the selection box.


Click on an empty region and drag to make a box selection in Invert Selection mode.


Use an open box selection to select all objects any part of which are within the selection box.


Selection in Tables


When we open a table that's linked to a drawing, the table window will show selected records with a light selection color background.


images\selmap_eg5.gif images\seltable_eg5.gif

For example, the four states selected in the drawing at left will have their records in the table highlighted with selection color. (The records are alphabetical sort order so Nevada and Utah are not seen in the fragment of the table shown above).


The Selections pane shows the same saved selections for both a drawing and any tables associated with that drawing. If we choose a saved selection to be previewed, the records will be highlighted in preview color in the table as well as being shown with preview color in the drawing.



For example, if we click on the Table window to move the focus to the table, the Selections pane will still have two saved selections called South West States and Mountain West. We can click on Mountain West to highlight it and press in the Preview button to preview it.


images\selmap_eg8.gif images\seltable_eg8.gif

As seen in the illustration above the states in the Mountain West saved selection will be highlighted in preview color in the table. Regardless of which window has the focus, a preview involving objects that appear in both drawings and tables will preview them in blue in all the drawing and table windows in which they appear.


It is clear from the hatch patterns which objects in the drawing appear both in the current selection and are being previewed from the Selections pane. In tables, records that are both selected and are in the preview will be shown in a color midway between the selection color and the preview color. By default, the combined color is light purple.


Selecting Records


Clicking on a record handle in the table is the same as a Select Touch on that record. We can also use CTRL-click and SHIFT-click.


images\seltable_click1.gif images\seltable_click2.gif

In the illustration above we click on the record handle for the Nevada record to select it. Selecting a record will combine it with any existing selection in accordance with the selection mode (Replace, Add and so on) currently in force.


images\selmap_eg10.gif images\seltable_eg10.gif

For example, we could change the selection mode to Add and then click on the record handle for the state of Alabama and several other states to add them to the selection shown in previous illustrations. The selection will be updated both in the drawing window and in the table window.


We can select items using any combination of selection in the map via mouse-based selection tools or selection in table windows via a variety of point-and-click highlighting methods within the table. For example, we could sort the table by clicking on a "population" field and then select only those records within a particular population range. We could then save this selection in the Selections pane. At any time this saved selection could then be combined with another selection made in the drawing or in the table.


This free-form way of selecting from within tables or maps is one of Manifold’s most original and most powerful concepts. Throughout Manifold we can get exactly the selection desired by clicking in different windows under the control of selection modes, saving selections within the Selections pane and then using selection command buttons from the Selections pane to combine saved selections with the existing selection. Sometimes it is very convenient to find records in tables by sorting columns and then selecting the topmost few records in the table to also select them in the map. See the Selection in Tables topic for more.


To select a range of records, click on the first record handle and then SHIFT-click on the last record handle. This will select all records (in accordance with the selection mode set) from first to last.


Note: clicking on a cell in a table makes that cell the active cell. To select a record in a table by clicking on a cell we can CTRL-click the cell. See the Working with Tables topic.


Showing only the Selection in Tables


To show only selected records in a table we open the table and push in the Filter Selected button either in the main toolbar or in the View - Filter dialog.




The table will then show only selected records. Records will appear and disappear from a table window filtered with Filter Selected as they are added to or subtracted from the selection by actions in other open windows.


SHIFT key for "Open" Mouse Selection


The keyboard’s SHIFT key may be used in combination with mouse selection to "open" the mouse selection.


By default, mouse selection commands will select all those items that are entirely within the selection shape that’s drawn. The SHIFT key "opens" the selection so that it grabs all items any part of which is within the shape drawn with the mouse. For pixels in images, or points in drawings "open" mode is the same as the default. For lines or areas in drawings "open" mode is a way of selecting all objects that touch or are within the mouse box.



Drawing the above box over the US_Main map selects only those states that are entirely within the box.



…In this case, just one state.



If we hold down the SHIFT key while making the same selection…



…we select all states that touch or are within the box.



SHIFT Touch Selection in Images


Just like using the SHIFT key causes a more inclusive selection in drawings, there is also an analogous SHIFT key function for touch selection in images.


images\img_touch_sel_eg01.gif images\img_touch_sel_eg02.gif


Using touch selection to click on a white pixel in the image at the left will select all pixels within the tolerance threshold that are contiguous (ie, adjacent to each other). In this case, white pixels between the legs are selected but not those on other sides of the legs.


Using SHIFT - touch selection to click at the same spot will select all pixels within the tolerance threshold throughout the entire image no matter where they are located. In this case, all of the white pixels within the tolerance level have been selected throughout the image.


Tip: Using SHIFT - touch selection is a good way to select pixels to replace a color throughout the entire image. Select the color throughout the entire image and then use either Hue / Saturation to change the color or the Paint Bucket tool with the SHIFT key to pour a different color into the selection throughout the entire image.


Speed of Select Touch in Images


Determining whether or not pixels are within a contiguously connect region requires many spatial computations, so SHIFT-touch selection frequently will operate much faster than touch selection.


CTRL Key and Select Touch in Images


Holding down the CTRL key while using Touch Select with images will select only that pixel that is touched. CTRL - touch is used when zoomed far into a map to "clean up" selections pixel by pixel.


images\img_alt_touch_eg01.gif images\img_alt_touch_eg02.gif


For example, the illustrations above show an image at great zoom where we wished to select only the lighter regions. The image at left shows that one of the black pixels is selected. We can deselect it by clicking it using CTRL- touch with selection mode set to Subtract. This method allows us to easily add or subtract individual pixels from the selection.


Autoscroll and Selection


When making freeform selections, Manifold will autoscroll the window to allow us to move the window even in the middle of a selection command. Autoscroll may be turned off or configured in Tools - Options .


Touch Selection Accuracy


Touch selection will select objects and pixels within a 4 screen-pixel radius of the actual screen pixel touched. This setting makes it possible to "touch" objects reliably without frustration even on higher resolution monitors. If touch selection chooses unwanted objects or pixels that are very close to the location touched, zoom in to provide greater spacing and touch again. At greater and greater zoom levels, individual pixels within images will enlarge until they take up many screen pixels as seen in the illustrations above.


Touch Selection Tolerance Setting


Touch selection will select all pixels whose color is within a given tolerance range of the pixel touched by the mouse. For RGB or RGBa images, tolerance is computed only on those channels that are made visible in the layers pane. For palette images, tolerance is computed based on the R, G and B values of the palette color as compared to other palette colors. Change the tolerance setting as desired in the Tool Properties pane to increase or restrict the range of pixel color values that are selected when using touch selection.


images\img_bronze_tolerance01.gif images\img_bronze_tolerance02.gif images\img_bronze_tolerance03.gif


In the illustrations above we have increased tolerance from a low level to a much higher level and then clicked on the blue sky just above the head of the monument. As tolerance is increased a greater number of pixels are selected in colors that are more and more different from the blue hue of the touched pixel. At high tolerance settings pixels with colors very different from the touched pixel will be selected.


Selections are Shown in their Map Layer


Selections are shown in all of the image or drawing layers in which they occur. If a selection is made only in a lower layer, upper layers might cover it.




Suppose we have one RGBa image based on our sample bronze image that consists of regions of visible, partially transparent pixels as well as invisible pixels. We can use Select Circle in the image window to select only that part of the circle that is over visible pixels. It selects all visible pixels, even those with low opacity specified using RGBa pixel transparency.




Suppose we open another image window showing our standard schloss image. We can make a Select Box rectangular selection in the schloss image window.




We can display both images together in a map window. The selections made in each image window will appear in the layer associated with their image. Seeing the two selections together in the map window shows both selections have been made independently.




Suppose now we click on the bronze image window and deselect the selection made in the bronze image and change the Selection Style to use a border style. The illustration above shows the resultant map window view. Because the bronze image is above the schloss image in the map layer stack, the head of the bronze image covers not only the schloss image pixels but also the selection indication. Since the bronze image is an RGBa image that is partially transparent even near the head, if we look carefully we can see a hint of red selection border peeking through the bronze image.


Note that selections are properties of the individual components, not of a map overall. A "map" is just a stack of layers of components like images and drawings. Clicking on a layer's tab to make it active directs the focus of what we do to that layer. Any selections we make by default will be for that layer.


The above examples clicked open image windows for the bronze and the schloss image so that selections could be made in those image windows. Selections can also be made in the map window, in which case they apply to the active layer if it is visible. By default, using a selection tool in an active layer if that layer is not visible has no effect. Selection tools apply to all visible layers when the ALT key is pressed even if the active layer is not visible. Had we made the rectangular selection in the map while pressing the ALT key, we would have selected those pixels both in the bronze image as well as in the schloss image that fell within the selection box.


Selection in Maps / ALT Key in Maps


Selection and Clipboard (Cut, Copy, etc) operations in maps work on the active layer by default. To extend the action of these operations to all visible layers, press the ALT key. For example, drawing a selection box in a map will only select objects in the active layer. Holding the ALT key while drawing a selection box will select objects from all visible layers. Pressing Delete deletes selected objects in the active layer only. Pressing ALT-Delete deletes selected objects in all visible layers. Think of ALT as a mnemonic for "All."


Menu items that appear when a map window has the focus will apply only to the active layer. For example, Edit - Select All, Select None and Select Inverse apply to the active layer only, as does Edit - Copy. Menu commands cannot be extended to include all layers. The ALT key works only with mouse selection methods and keyboard commands. It does not modify menu commands (such as Edit - Copy) which always work on the active layer.


To apply selection commands to all visible layers, use the ALT key together with a mouse-based selection command such as Select Box or with a keyboard short cut such as CTRL- C or with a keyboard shortcut such as CTRL-A. For example, and ALT-Select Box used with Invert selection mode will create an inverse selection over all visible layers. ALT-CTRL-A will select all objects from all visible layers. If all objects in all layers are selected, ALT-CTRL-I ("select inverse" applied to all objects) will deselect all objects.


See the Layers and Commands topic for an example of the above.


Image and Surface Selection Commands


Certain selection commands are available only in images and surfaces. See the Selection using Masks and Modifying Selections topics.


Menu Selection Commands


Don’t forget about the selection commands available under the Edit menu (See also the Edit - Select All / None / Inverse topic for handy menu based selection commands):


Select All

Select all objects or pixels in the component.

Select None

Deselect all objects or pixels in the component.

Select Inverse

Invert the selection. Those items that were not selected will become selected, while those that were selected will be deselected.


images\sc_edit_select_all.gif images\sc_edit_select_none.gif


Select All and Select None are obvious in action, as seen above using an image as an example.


images\sc_edit_select_inv01.gif images\sc_edit_select_inv02.gif


Select Inverse is a very useful command, because sometimes when making a selection it is easier to pick out those things we do not want to select. For example, if we ultimately would like to select the land area of South America in the images above, it is easier to first use Touch Select to select ocean areas and to then use Edit - Select Inverse to get the land areas. The ocean regions are very even in color and can be selected with a single click. The land areas contain many different colors and would take many clicks when using a reasonable tolerance setting with Touch Select.


images\sc_edit_select_inv03.gif images\sc_edit_select_inv04.gif images\sc_edit_select_inv05.gif


These commands also work with drawing layers. In the sequence above, we would like to retain a circular region of lines in a drawing layer while deleting all other lines. We do this by selecting the circular region, choosing Select Inverse and then deleting the new selection (all the lines except the ones we want).


These commands also work with tables and even forms.


images\sc_edit_select_inv06.gif images\sc_edit_select_inv07.gif


For example, if one control in a form is selected, using Select Inverse will select the other controls.


Transferring a Selection between Components


The Transfer Selection command can transfer a selection from one component to another when the two components are used together as layers in a map. For example, we can use it to select all pixels in an image that are within selected areas in a drawing. See the Transfer Selection topic for more.


Keyboard Zoom Commands during Selection and Editing


When making selections or editing objects (such as inserting areas using the Autocomplete feature) we will often want to zoom in or out in the middle of a selection or editing command. Use the + and - keys on the keyboard to do so. Usually the + and - keys in the numeric keypad are used.



"Plus" key: Zoom in at the current tool position.


"Minus" key: Zoom out at the current tool position.


The current tool position is the position of the mouse at the time the + or - key is pressed. When editing, using these keys allows us to easily zoom into a desired location, make a few precise clicks and then zoom back out and proceed at the usual scale.


Status Bar Selection Readout




The leftmost portion of the status bar has multiple uses. It normally is used to show extended messages that accompany tool tips when the mouse cursor hovers over a command button.




For some commands, like selection commands, the leftmost portion of the status bar will be used to show the dimensions of the area selected in the units used for the current projection taking into account the local scale and units settings in the Edit - Assign Projection dialog for that component. If the component is georegistered the sizes shown will be true dimensions.


See Also


ViewBots for an example using ViewBots to make selections using Selection Commands from the ViewBots pane.

Query Toolbar for selection via the query toolbar.

Selecting Objects with Queries

Transform Operators - Drawings for a list of transform operators that make selections.



See the Dialog Mode and Visual Tools topic for a parameter or value oriented way of specifying a selection shape.