Using the Geometry Workspace
The Geometry workspace window provides the graphical interface of the EMPro project. Within the window, there are a series of View Tools along the right of the viewing area that can be used to manipulate the view of the simulation space at any time. Along the top of the viewing area, the window contains Geometry Tools used to create and edit various aspects of the project geometry, in preparation for the final calculation.
The first drop-down menu in the upper-left part of the Geometry workspace window contains four different tools:
- Geometry Tools
- Component Tools
- FDTD Grid Tools
- Sensor Tools
The following figure displays a Geometry workspace window:
This section focuses on geometric modeling within the EMPro interface. It begins by describing the basic functions available within the Geometry workspace window, where the project geometry is created.
For more about creating and editing discrete components with Component Tools, refer to Defining Circuit Components and Excitations.
For more about controlling the characteristics of the grid and meshing parameters with Grid Tools, refer to Defining the Grid and Creating a Mesh.
For more about collecting data in EMPro with Sensor Tools, refer to Saving Output Data with Sensors.
The View Tools option which is available for orienting the perspective of the simulation space, is detailed in the following section.
Under Geometry Tools, you will be introduced to the 2-D and 3-D modeling tools, modification and boolean operations, and patterned arrays that are available within this dialog. In addition to creating geometry from scratch within Geometry Tools, external files, such as CAD and voxel files, can also be imported and modified.
After the geometry is created or imported into a project, it is often necessary to adjust an object's orientation. EMPro has the capability of orienting not only geometric parts, but also other physical parts, such as components and sensors.
The final section details the Specify Orientation tab that is available during any editing session involving a physical part.
The View Tools are used to alter the perspective of the viewing window by manual rotation, translation, and zoom, as well as automatic orientations to achieve the desired perspective. The View Tools are visible on the right-hand side of the Geometry workspace window. They can also be found in the top left-hand corner under the View drop-down menu, as shown in the following figure:
The View Tools may be hidden by right-clicking the toolbar and deselecting the toolbar check-box. The toolbar can be unhidden at anytime using the View drop-down menu.
Each tool is detailed below.
Using View Manipulation Options
The View Manipulation tool provides the following options:
- Zoom to Window
The Select tool is the default tool in the Geometry workspace window. It is used to select objects as well as manipulate the view of the simulation space.
- Rotation about a fixed point:
- Left-click and drag.
- Click the mouse wheel and drag.
- Translation (panning):
- Right-click and drag.
- Hold Shift, left- or right-click and drag.
- Roll the mouse wheel backwards or forwards (to zoom-in or zoom-out, respectively).
- Hold Ctrl, left-click and drag the mouse up or down (to zoom-in or zoom-out, respectively).
The Orbit tool is selected to perform rotation of the simulation space through left-clicking-and-dragging.
The Pan Tool tool is selected to perform translation of the simulation space through left-clicking-and-dragging.
Zoom-in or zoom-out of simulation space by left-clicking-and-dragging the mouse up or down, respectively.
Zoom to Window
Zoom into a rectangular shaped area of the geometry as specified by the user. To use, select the tool, then left-click and drag the mouse to designate the rectangular zoom area.
Zoom to Extents
Select this tool to automatically zoom so that the entire geometry can be viewed in the simulation space.
Standard View, Isometric View, and Custom View
The Standard Views and Isometric Views buttons function to automatically change the perspective of the objects in the Geometry workspace window.
The Standard View changes the view to the following orientations:
- Front (-Y)
- Back (+Y)
- Top (-Z)
- Bottom (+Z)
- Right (-X)
- Left (+X)
The Isometric View changes the perspective to any combination of these views:
If these buttons do not achieve the desired perspective, use the Select, Orbit or Pan tools to customize the orientation, and save the desired view by clicking the Custom Views > Add View button.
This tool measures the 3-D distance between any two points by left-clicking on a starting point and dragging to an ending point. A box in the lower-right corner of the GUI displays the coordinates of the cursor position in 3-D space. A box in the lower-left corner of the GUI displays axis-aligned distances:
The following illustration shows the Measure Tool calculating the distance between the corners of a rectangle.
Using the Measure Tool
Field Reader Tool
The Field Reader tool measures field values at the location where the mouse hovers over the geometry. For more information on the field reader tool, refer to Viewing Output.
Export Image Tool
The Export Image tool takes a screen shot of the geometry as it is currently shown in the Geometry workspace window, and saves it to a specified location.
Opacity and Visibility Tools
The Visibility buttons control the view of parts of the project.
Clicking any of these buttons will hide its corresponding objects. They include:
- Parts View - Toggles the geometric parts on and off.
- Circuit Components View - Toggles the circuit components on and off.
- Sensors View - Toggles the sensors on and off.
- Result Fields View - Toggles the result fields on and off.
Clicking the Opacity button located to the right of any button, will bring up a slider to customize the translucency of its objects. The sliders change the alpha of the objects, making them more or less translucent as the slider is dragged right or left, respectively. When the project is in Mesh View mode, these buttons are convenient for turning off the view of the solid geometry so that the view of the cell edges is not obstructed.
There are several ways EMPro can render this translucency. For more information on how to adjust these settings the notes on Transparency Algorithm, refer to Application Preferences.
This button toggles between Mesh View and Normal View. Alternatively, double-clicking the FDTD: Mesh branch of the Project Tree will enable Mesh View.
When in Mesh View, there are two main viewing modes, Mesh Cutplanes and 3D Mesh, that are controlled by radial buttons along the bottom of the Geometry workspace window. A valid mesh must be generated to use these viewing options. For more information on generating a mesh with the Meshing Properties Editor, refer to the Meshing Properties Editor in "Defining the Grid and Creating a Mesh".
The first mode, Mesh Cutplanes, creates cutplanes of the mesh in any or all of the three primary planes. Toggle any of these cutplanes on or off by checking or unchecking their respective boxes. The sliders associated with each of these planes are enabled when its respective plane is turned on. The slider moves the cutplane throughout the slices in the mesh. Additionally, each checked plane will activate the following icons, which aid in manipulating the cutplanes view:
- Cuts Away solid geometry on the +Z side of the mesh slice.
- Toggles viewing edges normal to the slide.
- Toggles viewing the grid.
- Toggles rendering of all the electric components.
- Toggles rendering of all the magnetic components.
There are also two check boxes available:
- View Mesh Information - Displays a dialog box with information about the mesh at the location of the mouse.
- Synchronize Sliders - Moves the cutplane simultaneously with a slider adjustment while the mouse button is still pressed.
The following illustration shows this first mode that is displayed when the Mesh View icon is selected. Note that this is only a preview of the mesh when it is shown while editing the grid within the Grid Tools dialog. Any other time, it is a representation of the most recently generated mesh.
Viewing the mesh
The second mode, 3D Mesh, provides several different options to view the mesh. Select any of the radial buttons within this option to create a customized three-dimensional view of the mesh. The Mesh Visibility icons are available in this mode as well so that Electrical and Magnetic components of the mesh may be toggled on and off. Additionally, the Material Visibility button controls which specific materials are visible in the view.
The figure below shows an object in 3D Mesh mode with All Edges displayed.
Viewing a 3-D mesh
The Automatic Remeshing feature is located in the View Tools toolbar. When this feature is enabled, remeshing is performed any time a change is made to the geometry. If this feature is not enabled, remeshing must be performed manually. Automatic Remeshing is not desirable when large meshes are imported because of their memory and performance demands.
The Automatic Remeshing dialog
Toggle Bounding Box Visibility
This button toggles the visibility of the bounding box for the geometry when the geometry is selected.
Toggle Output Viewing Controls
This button toggles the visibility of the output viewing controls for sensor results.
EMPro provides Feature Based Modeling that allows the creation of geometric objects as a set of repeatable actions rather than one stringent primitive object. This provides more flexibility in customizing an object and allows any unwanted step to be easily undone by use of the Undo button without using excess memory that was formally required to rebuild an entire object. It also tracks every step in the modeling sequence as a separate object in the tree to facilitate even simpler additions, deletions and modifications to the modeling sequence.
This section describes the Geometry Tools interface, through which geometric modeling in EMPro is performed. This interface enables the user to create new geometry, modify existing geometry, perform boolean operations such as unions, subtraction, and intersections, and create patterns. To begin using Geometry Tools, open the Geometry workspace window and select Geometry Tools from the drop-down menu. A more comprehensive discussion of each Geometry Tool is available in the "Appendix of Geometric Modeling".
Creating New Geometry: After selecting Geometry Tools in the drop down list of the Geometry workspace window, click Create to prompt a drop-down menu to appear. This menu includes the modeling operation options. For more information, refer Creating a New Geometry.
Using Feature-Based Modeling
Parts are created in a step-by-step sequence (such as extrude, revolve, and boolean) that propagate through during creation as the part becomes more complicated. Each step can be re-entered and edited separately.
It facilitates undo/redo operations, parameterization, and constraints
Integrating 2D and 3D Editing
3D objects are created by operations on 2D cross-sections. The global (X,Y, Z) and local (U,V,W) coordinate systems allow easy rotation and translation of objects (connector example).
For more information, refer to Orienting Objects in the Simulation Space.
Modifying Existing Geometry
You can use the Modify menu in the Geometry browser window to modify the geometry of existing objects in the project. This menu provides the following options:
- Create a 3D object
- Translate the object
- Rotate the object
- Chamfer Blend any corner
- Shell Offset Faces from a 3D object
Performing Specific Rotation
Using the Modify menu, you can move and rotate the object with reference to a point:
- Create an object
- Select specific rotation menu
- Move and rotate object
For chamfering the edge, perform the followings steps:
- Create an object.
- Select Chamfer edges.
- Perform operation by selecting one edge.
For shelling the object, perform the followings steps:
- Create an object.
- Select Shell Faces.
- Perform operation by selecting one face.
Performing Boolean Operations
The following Boolean operations need to be tested:
- Two Parts: The Two Parts tool provides several boolean operations to subtract, intersect, or unite two objects. To test these feature create two objects, one object must be selected to be the BLANK, and the other the TOOL which acts on the blank.
- Extrude: Using the Extrude tool, you can perform an operation on an existing geometry part. In this case, the user chooses the Blank, and then creates the object to use as the TOOL. The user then specifies the orientation of the extrusion and the nature of the operation (Subtract, Intersect, or Union). In essence, this operation is a shortcut for the Two Parts Boolean operation.
- Revolve: Using the Revolve tool, you can perform an operation on an existing geometry part. The user chooses the Blank, and then creates the object to use as the Tool. The user then specifies the orientation of the revolution and the nature of the operation (Subtract, Intersect, or Union).
Holes may also be extruded, revolved, or swept through any part any with its respective tool in this menu.
Patterns are created by replicating a single selected object multiple times in one of the organized arrangements listed below:
- Linear pattern
- Cylindrical pattern
- Hex-cylindrical pattern
- Spherical pattern
- Elliptical pattern hex pattern
- Radial pattern
- Polar grid pattern