Tetrahedral and surface triangular meshes are one of the most widely used mesh types in many different engineering disciplines. CubeCAD provides two types of mesh generation algorithms for [[Discretizing Objects|discretizing objects]]. The first one generates a wire-frame surface triangular mesh of surface objects and a polyline mesh of curve objects. The solid objects are treated as closed surfaces and are discretized using a similar wire-frame surface mesh. in other words, objects of all types are meshed in some sort. The wire-frame mesh generator has two variations. The first algorithm generates a regularized mesh and attempts to create triangular cells of almost equal size. The second algorithm tries to create a structured mesh with cells of similar patterns. CubeCAD's other mesh generator generates a tetrahedral mesh for solid objects. Tetrahedral meshes are usually enormous in size. Note that surface and curve objects cannot be discretized using this type of mesh generator.
<table><tr><td> [[FileImage:cadmesh1_tn_new.png|260pxthumb|left|400px|The geometry of a sphere.]] </td></tr><tr><td> [[FileImage:cadmesh2_tn_new.png|260pxthumb|left|400px|The triangular surface mesh of the sphere generated by CubeCAD.]]</td>A sphere and its surface triangular and tetrahedral meshes.</tr></table>
===Generating and Controlling the Mesh===
[[File:cadmeshsettings_new.png|thumb|250px|CUBCAD's Mesh Settings dialog.]]
You can generate a mesh of the structure in [[CubeCAD|CUBECAD]] in one of the following three ways:
# By clicking the '''Show Mesh'''[[File:mesh_tool_tn.png]] button of '''Compute Toolbar'''.
When the mesh is displayed in the Project Workspace, [[EM.Cube]]'s mesh view mode is enabled. In this mode, all the objects are discretized using the selected mesh generation algorithm and the meshes of all objects are displayed. In mesh view, you cannot mouse-over, select or edit any objects. The mesh view is for viewing purpose only. You can perform most of view operations such as zooming in and out using the mouse scroll wheel, rotating the view using the right mouse button '''RMB''' and panning the view using '''Shift+RMB'''. When [[EM.Cube]] is in mesh view mode, the '''Show Mesh'''[[File:mesh_tool_tn.png]] button of Simulate Toolbar remains depressed. To hide the mesh, exit the mesh view mode and return to the normal view mode, simply click the '''Show Mesh'''[[File:mesh_tool_tn.png]] button one more time to toggle its state, or press the keyboard's '''Esc Key''' (Escape), or select the menu item '''Simulate → Discretization → Show Mesh''' and remove the check mark in front of it.
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[[Image:cadmeshsettings_new.png|thumb|left|480px|CubeCAD's mesh settings dialog.]]
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You can change the mesh type and the mesh resolution from the CAD Mesh Settings Dialog. Click the '''Mesh Settings'''[[File:mesh_settings_tn.png]] button of '''Simulate Toolbar''' or select the menu item '''Simulate → Discretization → Mesh Settings...'''In the drop-down list labeled '''Mesh Type''' you can select one of the three options: '''Regular Surface''', '''Structured Surface''' or '''Tetrahedral'''. The mesh resolution is controlled by '''Edge Length''' which is expressed in project units. The default value of edge length is 10 units. This means that the default mesh features cells with a size of about 10 units. When you change the mesh type or resolution, you can see the effect using the '''Apply''' button if [[EM.Cube]] is already in mesh view mode. After [[EM.Cube]] generates a mesh, it saves its and uses it the next time you want to see the mesh. The mesh stays the same until you change its parameters. Sometimes, you may want to regenerate the mesh with the same current parameters. To do so, select the menu item '''Simulate → Discretization → Regenerate Mesh'''.