Example: Change the Shape of Areas

Please review the Editing Drawings topic before proceeding.    In this topic we show a sequence of editing moves using illustrations that show a drawing layer in a map next to a view of the Info pane.

 

To edit the geometry of an existing object, Alt-click on that object to pick it and then click any vertex or segment to shift into Move Coordinates editing mode.   The object is readied for editing and the Record pane immediately pops open to display the Coordinates tab, showing coordinates of vertices, that is, the geometry, of that object.

 

These examples use an area object.  The same techniques apply to editing lines.   Editing points is simple: Alt-click the point to launch the Info pane to enable viewing or editing of attributes.  Click the point again (or click the Coordinates tab in the Info pane) to put the point into Move Coordinates mode so it can be dragged to a new location.

Example: Move a Vertex

A vertex is one of the coordinates that defines an object.   Many GIS packages use the term vertex instead of coordinate.   To change the shape of an area we move the vertices that define the shape of the area, perhaps also adding or removing vertices.

 

To move a vertex in an object:

 

  1. Alt-click on the object and then click the vertex to be moved. Blue boxes appear at the vertices that define the object, and the active vertex is indicated by a larger box. The Info pane automatically switches to the Coordinates tab.

  2. Drag the vertex to whatever position is desired.

  3. The new location will be previewed both in the drawing and in the Coordinates tab table in blue preview color.   Right-click in the drawing and choose Save Changes, or press Ctrl-Enter, or press the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit.  To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

 

We open a map with a drawing layer that shows buildings in Monaco, the data having been imported from the OpenStreetMap data set.   We zoom in for a detailed view of some of the buildings.  Alt-click the area to be changed, to pick that area.   

 

The vertices of the area are highlighted as small boxes in light blue preview color, with the area border line segments between blue vertex boxes also drawn in light blue  preview color.   The Info pane automatically opens to show the contents of attribute fields in the Values field, ready to edit those field values if we desire.

 

 

To switch into Move Coordinates editing mode, we click any vertex or segment.  To save time, we click the vertex we intend to move.

 

 

 

The edit handles on coordinates become slightly larger, and the vertex we clicked becomes a large box to indicate it is the active vertex.  The Info pane switches to the Coordinates tab showing the coordinates of vertices.  The Coordinates list displays coordinates of vertices in the native projected units of the drawing.  Those units are  meters in this case, since the drawing is in Pseudo Mercator projection.  

 

The context or active vertex is marked with a dark row handle in the Coordinates list and with a larger box in the drawing.  We can drag the active vertex to a new position.   To choose any desired vertex as the active vertex, we can click on it.   We can then drag the active vertex to whatever new position is desired.   

 

 

We drag the active vertex to a new location.  As we drag, the outline shape of the area rubber-bands to the position of the cursor.  The new outline shape of the area will be shown in light blue preview color.   The changed coordinates of the active vertex will also be displayed in the coordinate list in light blue preview color.

 

 

To apply the change, we can Right-click anywhere in the drawing and choose Save Changes from the pop-up menu.  Alternatively, we can press Ctrl-Enter as a keyboard shortcut or we can press Update Record in the Info pane.

 

When we commit the edit, the area is redrawn in the changed shape, and the Info pane switches to the Values tab.   The area is still alt-clicked as the active object for the Info pane.   

Example: Move Multiple Vertices Together

Moving multiple vertices together is similar to moving one vertex.

 

To move multiple vertices together:

 

  1. Alt-click on the object and then click the vertex we would like to use as the main handle to move the group of vertices we intend to move. Blue boxes appear at the vertices that define the object, and the vertex is indicated by a larger box, to show it is the active vertex. The Info pane automatically switches to the Coordinates tab.   

  2. Ctrl-click the active vertex.  That will select it.  The edit handle will change to dark blue and the vertex's row in the Coordinates list will be shown with red selection color.

  3. Ctrl-click on any additional vertices we intend to move, to select those vertices as well.  We can also use other selection mouse moves, like a selection box drawn with Ctrl-drag.

  4. Drag the large, dark blue, active vertex to the desired position.   All other selected vertices will move along with that box.

  5. The system will preview the result using blue preview color.  Press Ctrl-Enter or the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit. To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

We Shift-Alt-click the area to be changed.   Next, in the drawing, we click the first of the vertices that will be moved together.    Clicking the vertex marks it with a larger box, and in the Coordinates list marks that coordinate's row with a darker row handle in the Coordinates list.    

 

We Ctrl-click that vertex to select it.

 

In the drawing, the edit handle for the vertex appears in dark blue preview color.   In the Coordinates list, the selected row appears in red selection color.  In the drawing, the edit handle for the vertex appears in dark blue preview color.

 

In the drawing we Ctrl-click all vertices we want to move together, to select them.   They appear in red selection color in the Coordinates list and their handles in the drawing appear in filled-in, darker blue preview color.

 

Selected vertices do not need to be next to each other.  All selected vertices will move together, whether they are next to each other or not.  In this example we select vertices next to each other, but they do not need to be next to each other.  If desired, we can select whatever vertices in the object we want and they all will move together if any one of them is moved.

 

 

When we drag the active, larger vertex handle to a new position, all selected vertices will move with it as if we had applied exactly the same mouse motion to them.  The resulting new shape of the area is shown in blue preview color.

 

Pressing Ctrl-Enter on the keyboard applies the change, or we can press Update Record in the Info pane, or right-click in the Map window and choose Save Changes.     

 

In the example above, we selected the vertices to be moved together by Ctrl-clicking them in the drawing.   Another way to select vertices is to Ctrl-click their rows in the Coordinates list.  We can Ctrl-click them one at a time, or to select a swath of many rows we can Ctrl-click the first row and then Shift-Ctrl-click the last row to select those rows and all in between.

Example: Move an Entire Object - Shift Drag

There are two basic ways to move an entire object.  The first way is a convenient shortcut:  Shift-dragging the active vertex moves all vertices in the object as well.   The second way is similar to moving multiple vertices.  We simply select all vertices in the object and then if we drag any of those vertices, all the other vertices move as well.  

 

This example shows the fastest way, Shift-dragging the active vertex.   It is followed by two more examples that show two different ways to select all vertices, so a drag on any of them moves the entire object.

 

To move an entire object using Shift-drag:

 

  1. Alt-click on the object and then click the vertex we would like to use as the main handle to move the entire object. Blue boxes appear at the vertices that define the object, and the vertex is indicated by a larger box, to show it is the active vertex. The Info pane automatically switches to the Coordinates tab.

  2. Shift-drag the vertex to whatever position is desired.  All of the other vertices will move as well, thus moving the entire object.

  3. The new location will be previewed both in the drawing and in the Coordinates tab table in blue preview color.   Right-click in the drawing and choose Save Changes, or press Ctrl-Enter, or press the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit.   To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

 

We Alt-click the area to be changed.   Next, in the drawing, we click the vertex that we will use as the main handle to move the entire object.   Clicking the vertex marks it with a larger box and also marks that coordinate's row with a darker row handle in the Coordinates list.  

 

Tech tip: Experienced users will think ahead when clicking the vertex that will be used as the main handle to move the entire object with a Shift-drag.  Very often we will want to use snapping to move the entire object exactly to some spot to which the cursor snaps, such as a corner vertex of some adjacent object.   When we Shift-drag the active vertex, snapping will apply to that active vertex position as we Shift-drag it, so we should pick an active vertex that will be convenient to snap to a desired location.  For example, if we want the right side of an area that we are moving to be snapped to a nearby, neighboring area, we should click a vertex on the right side of our area to use as the main edit handle.  Clicking a vertex on the left side will not allow us to snap the right side of our area into alignment as desired.    Of course, it is not a big deal if we realize we prefer a different handle, since we can always just click a different vertex and that vertex will become the active vertex.  But that is an extra click that experienced users will avoid.

 

 

Shift-drag the active vertex to a new location.   All of the other vertices will move with the active vertex, thus moving the entire object.

 

 

Pressing Ctrl-Enter on the keyboard applies the change, or we can press Update Record in the Info pane, or right-click in the Map window and choose Save Changes.  

Move an Entire Object - Select All Vertices with Mouse

Most people will move an entire object using the Shift-drag mouse shortcut shown in the example above.  An alternative way to move the entire object is similar to moving multiple vertices.  We simply select all vertices in the object and then if we drag any of those vertices, all the other vertices move as well.  

 

There are two ways to select all vertices in the object.  We can draw a selection box around all the vertices using a Ctrl-drag, the method shown in this example, or we can select all vertices in the Coordinates list, the method shown in the next example.

 

To move an entire object by selecting all vertices with the mouse:

 

  1. Alt-click on the object and then click the vertex we would like to use as the main handle to move the entire object. Blue boxes appear at the vertices that define the object, and the vertex is indicated by a larger box, to show it is the active vertex. The Info pane automatically switches to the Coordinates tab.  

  2. Ctrl-drag to draw a selection box that encloses all vertices in the object.  That selects all vertices.  The active vertex will be marked with a larger box.  

  3. Drag the bigger darkened vertex to the desired position.   All other selected vertices, that is, the entire object, will move along with that box.

  4. The system will preview the result using blue preview color.  Press Ctrl-Enter or the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit. To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

 

We Alt-click the area to be changed.   Next, in the drawing, we click the vertex that we will use as the main handle to move the entire object.   Clicking the vertex marks it with a larger box and also marks that coordinate's row with a darker row handle in the Coordinates list.  

 

We Ctrl-drag to draw a selection box that encloses the entire object.  That is easy to do, since we do not need to be precise: we simply draw a much larger selection box to be sure the entire object falls within the selection box.

 

That selects all vertices in the object.  All vertex handles for the object will switch to dark blue boxes, with active vertex shown as a larger, dark blue box.   All of the rows in the Coordinates list are selected and shown in red selection color.    

 

We can now drag the larger, active vertex to a new location, and all the other vertices will move with it.  This moves the entire object, with the new position previewed in blue preview color.   The Coordinates list shows the altered coordinates using a mix of blue preview color and red selection color.

 

 

Pressing Ctrl-Enter on the keyboard applies the change, or we can press Update Record in the Info pane, or right-click in the Map window and choose Save Changes.  

Move an Entire Object - Select All Vertices in Coordinates List

The previous example showed how to select all vertices in an object using a Ctrl-drag with the mouse in the drawing window.   An alternative way to select all vertices is to use a Ctrl-A keyboard shortcut in the Coordinates list, the method shown in this example.

 

To move an entire object by selecting all vertices in the Coordinates list:

 

  1. Alt-click on the object and then click the vertex we would like to use as the main handle to move the entire object. Blue boxes appear at the vertices that define the object, and the vertex is indicated by a larger box, to show it is the active vertex. The Info pane automatically switches to the Coordinates tab.  

  2. In the Info pane, click on the Coordinates tab to move the focus there.   

  3. Ctrl-A to select all rows in the Coordinates list.   That selects all vertices, coloring their rows red in the Coordinates list and redrawing vertices in the drawing using dark blue color.   The active vertex will be marked with a larger, dark blue box.  

  4. Drag the active vertex to the desired position.   All other selected vertices, that is, the entire object, will move along with that box.

  5. The system will preview the result using blue preview color.  Press Ctrl-Enter or the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit. To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

We Alt-click the area to be changed.   Next, in the drawing, we click the vertex that we will use as the main handle to move the entire object.   Clicking the vertex marks it with a larger box and also marks that coordinate's row with a darker row handle in the Coordinates list.  

 

In the Info pane we click on the Coordinates tab to move the keyboard focus to that pane.    Next, we press Ctrl-A on the keyboard to Select All, a standard Windows keyboard shortcut.     

 

Another way of selecting all coordinate rows would be to Ctrl-click the first row to select it, and to then Shift-Ctrl-click the last row to select that row and all rows in between.   Ctrl-A is faster and less error-prone.

 

All of the rows in the Coordinates list are selected and shown in red selection color.    All vertices for the area are selected, so all vertex handles for the area  appear in filled-in, dark blue color.

 

 

We can now drag the larger, active vertex to a new location, and all the other vertices will move with it.  This moves the entire object, with the new position previewed in blue preview color.   The Coordinates list shows the altered coordinates using a mix of blue preview color and red selection color.

 

 

We press Ctrl-Enter to commit the edit, or we can press Update Record in the Info pane, or right-click in the Map window and choose Save Changes.

Delete a Vertex from an Object

Deleting a vertex is easy: we select it in the Coordinates list and then press Delete.

 

To delete a vertex from an object:

 

  1. Alt-click on the object and then click the vertex we would like to delete, making it the active vertex. Blue boxes appear at the vertices that define the object, and the active vertex is indicated by a larger box. The Info pane automatically switches to the Coordinates tab.  

  2. In the Coordinates list, the row handle for the active vertex will darken, with the list cursor positioned in that row.

  3. Ctrl-click that row to select it.  The row will switch to red selection background color.  The vertex's box will change to dark blue color as well.    

  4. Press the Delete button in the Coordinate tab's toolbar.  That deletes the vertex.

  5. The system will preview the result using blue preview color.  Press Ctrl-Enter or the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit. To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

 

We Alt-click the area to be changed.   Next, in the drawing, we click the vertex to be deleted.  Clicking the vertex marks it with a larger box.  The Coordinates list marks that coordinate's row with a darker row handle. 

 

We Ctrl-click that row to select it.

 

When the row is selected, the Delete toolbar button becomes enabled.   

 

 We press the Delete button to delete the vertex.

 

 

The system previews the change for us in blue preview color.

 

We press Ctrl-Enter to commit the edit, or we can press Update Record in the Info pane, or right-click in the Map window and choose Save Changes.

Add a Vertex using Insert Coordinates

We can add one or more vertices, also called coordinates, to an object.   There are two ways to add vertices to an object.   One way is to switch to Insert Coordinates mode and to then click to add coordinates, that is, vertices.   Another way is to switch to Move Coordinates + Split mode, which allows us to click on a line segment to add a coordinate at that spot.  

 

Which method we choose depends entire on what we prefer.  The Insert Coordinates method might be quicker if we want to add a sequence of several new vertices in the same segment, while the Move Coordinates + Split method might be quicker if we want to hop around in the object, adding a coordinate or two to various different segments.

 

This example shows the use of Insert Coordinates.   The next example shows the use of Move Coordinates + Split.  

 

To add a vertex to an object using Insert Coordinates

 

  1. Alt-click on the object and then click the vertex after which we would like to add another vertex.  Blue boxes appear at the vertices that define the object, and the vertex we clicked is indicated by a larger box, to show it is the active vertex. The Info pane automatically switches to the Coordinates tab.    

  2. Press the I key on the keyboard to enter Insert Coordinates mode.  If we prefer, we can right-click into the drawing somewhere and choose Insert Coordinates mode from the context menu.

  3. Segments in preview color will rubber-band to the mouse cursor.  Click where the new vertex is to appear.  Click again to create additional vertices.

  4. The system will preview the result using blue preview color.  Press Ctrl-Enter or the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit. To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

 

Alt-click the object to be changed.   Next, in the drawing, we click the vertex at the beginning of the line segment on which we would like to add a new vertex.  Clicking the vertex marks it with a larger box.  

 

We press the I key on the keyboard to switch into Insert Coordinates mode.  If we do not remember the keyboard shortcut, we can right-click into the drawing and choose Insert Coordinates from the context menu.

 

 

In Insert Coordinates mode the mouse cursor is ready to create a new vertex with each click.  As we move the mouse cursor, segments from existing coordinates rubber-band to the cursor's position.  

 

Insert Coordinates mode swings into action for the whatever segment follows the active vertex.   If we made a mistake and wanted to start inserting coordinates at a different segment, we can switch back to Move Coordinates mode by pressing the M key, clicking a different vertex, and then once more pressing I to switch into Insert Coordinates mode.

 

 

We click to mark the desired location of the new vertex.  It appears in the drawing and a new row for the vertex appears in the Coordinates list.

 

 

Blue preview lines continue to rubber-band to the mouse position.  We can click to add more new vertices, or we can press Ctrl-Enter to accept the edit with one new vertex added.  To save changes we can also can press Update Record in the Info pane, or right-click in the Map window and choose Save Changes.  

 

Suppose we are happy with our work so far, but we would like to add vertices to some other segment.  We can do that by switching back to Move Coordinates mode by pressing the M key, clicking a different vertex that begins the desired segment, and then once more pressing I to switch into Insert Coordinates mode.

 

In this example, we are happy with our work and we press Ctrl-Enter to save changes.

 

 

When we press Ctrl-Enter the edit is committed and the area appears in the new, changed shape with a new vertex added.

Add a Vertex using Move Coordinates + Split

In the previous example we saw how to add vertices to an object using Insert Coordinates mode.   Another way is to use Move Coordinates + Split mode, which allows us to click on a line segment to add a coordinate at that spot.  This example shows the use of Move Coordinates + Split.  

 

To add a vertex to an object using Move Coordinates + Split:

 

  1. Alt-click on the object and then click any vertex to switch into editing mode, Move Coordinates by default.  Blue boxes appear at the vertices that define the object, and the vertex we clicked is indicated by a larger box, to show it is the active vertex. The Info pane automatically switches to the Coordinates tab.    

  2. Press the P key on the keyboard to enter Move Coordinates + Split mode.  If we prefer, we can right-click into the drawing somewhere and choose Move Coordinates + Split mode from the context menu.

  3. Click onto any line segment where we would like a new vertex is to appear.  When the vertex appears, we can drag it to a new position.

  4. Click again onto any other line segments to create additional vertices, and then drag them as desired. 

  5. The system will preview the result using blue preview color.  Press Ctrl-Enter or the Update Record button for the change to take effect.  Press Ctrl-Back to abandon the edit. To undo changes we can also Right-click into the drawing and choose  Undo Changes.

 

 

 

Alt-click the object to be changed.   We then click any vertex to shift into Move Coordinates editing mode.  

 

Next, we right-click into the drawing and choose Move Coordinates + Split from the context menu.  A keyboard shortcut for Move Coordinates + Split mode is to press the P key.

 

 

Move Coordinates + Split mode is like a super Move Coordinates mode.  It works just like Move Coordinates mode but with the addition of a Split capability:  Click on a line segment and a new vertex is added there, splitting the segment into two segments.   Move Coordinates + Split mode is so convenient it may become the default "Move Coordinates" mode.

 

In the illustration above, we click on a line segment to add a vertex at that spot.

 

 

A new vertex appears, with the line segment being split into two segments.   A new row for the vertex appears in the Coordinates list, shown in blue preview color.

 

 

We can drag the new vertex to whatever location we want.

 

 

At any time, we can click on a different line segment, to add a vertex at the spot clicked.

 

 

The new vertex appears in the line, splitting it into two line segments.  A new row appears for the vertex in the Coordinates list.

 

 

We can drag the new vertex to whatever location we want.

 

 

We click another line segment to add one more vertex.

 

 

 

We drag the new vertex to a new location.

 

We press Ctrl-Enter to save changes.  We can also can press Update Record in the Info pane to save changes, or right-click in the Map window and choose Save Changes.  

 

Notes

Moving non-adjacent vertices together - When moving multiple vertices, the vertices need not be adjacent.    We Alt-click the object to be changed, and then we Click one of the vertices to be moved.

 

 

Next, we Ctrl-click on three different vertices to select those vertices.  The three vertices are not all adjacent to each other.  In the Coordinates list the rows corresponding to selected vertices switch to red background color to indicate they have been selected.

 

The larger box is the active vertex.   We can click any of the vertices to make it the active vertex.  When we drag that vertex to a new location all of the selected vertices will move with it.  

 

If we click a non-selected vertex to make it the active vertex, when we drag a non-selected vertex that will move only that vertex.

 

 

Pressing Ctrl-Enter or clicking Update Record applies the change.  We can also right-click in the Map window and choose Save Changes.  

 

See Also

Getting Started

 

User Interface Basics

 

Drawings

 

Editing Drawings

 

Layers Pane

 

Info Pane

 

Example: Draw Lines, Areas and Points - Simple example of using basic mouse moves to add points, lines and areas to a drawing.

 

Example: Trace an Area in a Map over an Image Background - In a map with a drawing layer above an image layer, create an area object in the drawing by tracing over the outlines of something seen in the image layer below.

 

Example: Edit Coordinates While Creating an Object - When creating an object in a map using a tool such as Create Area, right in the middle of the process we can edit coordinates in the Info pane Coordinates tab.   This example shows the step by step process.

 

Example: Edit Attributes and Move a Point - We look at the attributes for a point in a drawing layer and edit one of the attributes using a more expanded Edit dialog.  We then move the point to a new location. Easy!

 

Example: Edit Attributes, Larger Text, IME for Asian Languages - A tour showing how to edit attributes in a drawing using the Info pane Values tab and the expanded Edit dialog, including advanced Unicode facilities and use of the built in Input Method Editor (IME) to input text in Japanese language.

 

Example: Create a Multipoint - This topic provides two examples:  First we create a multipoint and then next we create a multipoint having two branches.  The purpose of this topic is to help teach the implementation of geometry in Manifold and other spatial packages using an unusual and rarely met object type, the multipoint, which combines what appear to be many separate points into a single multipoint object.

 

Example: Edit Areas in a Layer to Align with Another Layer - Editing areas in one layer so their boundaries align, either all or in part, with boundaries of areas in a different layer is a common task in GIS and CAD. For example, we might want area boundaries in a layer with different zoning areas for tax or regulatory purposes to be guided by the boundaries of administrative jurisdictions, such as the boundaries of cities, in a different layer.  This example shows how, using fast and simple techniques.  

 

Example: Add Vertices in the Middle of a Line being Created - During the creation of a new object we can go back and make corrections, additions and deletions to coordinates already marked.  In this example we start creating a new line, and then notice we have skipped over some locations we wanted to click.  We go back to add those vertices (coordinates), and then we continue with creating the line.

 

Example: Edit Covered Objects - Working with drawings where some areas completely cover smaller areas is a bad idea, but sometimes we have to work with data in that form whether we like it or not.   This topic shows techniques that can help us select and edit objects that are completely hidden by higher objects.

Videos

Editing Drawings - Create Areas - How to create areas (polygons) in a drawing.  We digitize a lake by tracing over a background satellite image layer from a web server.  This quick video shows how editing tools in Manifold make it easy to digitize objects very quickly, correcting any errors with no stress or fear of getting it wrong.  Includes a quick demo of snapping.

 

Editing Drawings - Create Lines with Curves - A very short video showing how to create lines in drawings using straight segments and also circular arcs.  We create a line in a map of Paris showing our walk around circular ponds. Manifold can create polylines using straight line segments for classic polylines, or using curved segments that are circular arcs, ellipses, or splines for very smooth curves, a much faster and easier technique than clicking many points.  Super!