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1. In ArcMap, use the Customize dialog to load the sample. From the dialog go to the Toolbars tab and click Add From File. This will add the TIN Editor toolbar. Drag and drop the toolbar into some area of the ArcMap user interface and quit the Customize dialog.
   
2. At this point you can either create a new TIN from scratch or edit an existing TIN. To create a new TIN use the Create New TIN command. To use an existing TIN add it to the document, select it in the 3D Analyst toolbar dropdown, and select Start Editing TIN. The commands to Start and Stop Editing TIN work pretty much as one would expect. Undo will restore the TIN to its previous state relative to the last Save.
   
3. To add individual nodes to an editable TIN use the Add TIN Point tool. When the tool is selected a dialog will pop up that enables you to specify the height for the digitized points.
   
4. To add breaklines to an editable TIN use the Add TIN Line tool. When the tool is selected a dialog will pop up that lets you to specify properties for the breaklines. These include the breakline type, height information, whether or not digitized vertices should snap to existing nodes, and whether or not digitized breaklines are allowed to cross others (conflict detection). Single click the mouse to enter a vertex. Double click to finish entering a breakline.
   
5. To add polygons to an editable TIN use the Add TIN Polygon tool. When the tool is selected a dialog will pop up that lets you to specify properties for the polygons. These include the surface feature type (SFType), height information, whether or not digitized vertices should snap to existing nodes, and whether or not digitized polygon boundaries are allowed to cross other breaklines (conflict detection). When specifying a SFType of ‘replace’ the polygon you digitize will be added as a breakline, obtaining its heights from the surface. This is used to hold the terrain, along that boundary, in place. The polygon will then be buffered inward by the ‘Replace offset’ and inserted using the replace height. Single click the mouse to enter a vertex. Double click to finish entering a polygon.
   
6. Use the Set TIN Edge Type tool to change triangle edges between regular, soft, or hard edge types. When the tool is selected a dialog pops up with a dropdown list. The list lets you select which edge type to switch a selected edge to. Selected edges are those closest to a mouse click.
   
7. Use the Set TIN Tags tool to change node or triangle tags. When the tool is selected a dialog pops up. This lets you specify whether you intend to alter node or triangle tags, how these elements will be selected, and the tag value to assign to them. When altering triangle tags you have an option of selecting based on ‘Point intersect’ meaning the triangle you click on will be changed. ‘Polygon intersect’ means all the triangles inside a digitized polygon will be changed. ‘Flood by tag’ means all contiguous triangles with the same tag as the one you click on will be changed. ‘Flood flat area’ means all contiguous (near) flat triangles to the one you click on will be changed. When altering node tags you can select based on the closest node to where you click or all those within a polygon you digitize.
   
8. Use the Set TIN Triangles In/Out tool to toggle the void area flags of triangles. This defines the data region of the TIN. When the tool is selected a dialog pops up which lets you indicate whether you will select individual triangles by pointing at them are selecting groups of triangles that are inside a digitized polygon. For the selected triangles you can also indicate whether or not to make them inside, outside, or to toggle their current state.
   
9. Use the Delete TIN Breakline tool to remove breaklines from a TIN. Click anywhere on a breakline to remove it. You must be sure to click on or near the breakline of interest because if a non-break edge is closest to where you click nothing will happen.
   
10. Use the Move TIN Node tool to move a node from one location to another. Click on a node to select it then click on its new location to move it. Alternately, click on a node to select it, keep the mouse button pressed, and drag the node to its new location.
    
11. Use the Connect TIN Nodes tool to establish a breakline between two nodes. The breakline will get its start and end heights from the nodes. This is useful when you have a triangle edge creating a false dam or valley and you want to override the existing triangulation and enforce a linear feature on the surface. Its purpose is similar to an edge swap in other TIN editing packages. What’s better about this is the enforcement as a breakline ensures subsequent edits in the nearby vicinity will not undo the change. To connect two nodes click on the first node to select it then move the mouse to the target node and click. Note, after the first click a graphic line follower will display and snap to the closest valid node relative to the cursor’s current position. This helps to visually ensure the connection is what you want before you actually click a second time and commit the action.

Steps for compiling the DLL:

1. The VB code for this sample makes calls to one or more utility modules that are shared by a number of 3D samples. The shared modules are located in the 'Utilities' folder which is found directly below the main '3D Analyst' ArcObjects sample folder. In order to compile the DLL make sure you have the latest version of the shared modules installed. Additionally, there is a dependency on TinFilters.dll which is located in the ‘Surface_Analysis\Tin_Filters’ samples folder. This needs to be registered before compiling or adding and using the editing tools in ArcMap.