Learn about the editing of geometry and the surface commands Merge Geometry and Split Geometry in VRED.
Please note, there may be differences between your version of VRED and the video. See the video captions below for updated instructions.
Video captions: This tutorial will address the editing of geometry and will provide you insight into the surface commands, Merge Geometry and Split Geometry, in VRED Professional. As these commands have an important function in data preparation processes, we will become more familiar with their uses and applications in the following.
Please open the Scenegraph via the Quick Access Bar, by selecting the Graph icon. First off, we will split the surface geometry into its separate parts. Please activate the wireview view to get a view of your selected geometry by selecting the Wireframe option in the toolbar.
To start with this, please select the hood in our example scene, by holding down the Shift key and clicking on the desired geometry with the left mouse button.
Next, call up the Scenegraph menu by utilizing the right mouse button in the Scenegraph. Please note that when calling up the Scenegraph menu, your mouse cursor needs to be located over the selected node. In the sub-item Edit, we find, in the lower part, the commands, Split Geometry and Split Geometry into Primitives. With Split Geometry, VRED offers us the possibility to split our geometry into a selectable amount of surfaces, and therein lies the significant difference to Split Geometry into Primitives, as the geometry is automatically split into its smallest components. It is worth mentioning that the Split Geometry into Primitives function delivers a clear speed advantage over the Split Geometry function.
Because in our case, we want to split the present geometry into separate triangles, we execute the command, Split Geometry into Primitives. Autodesk VRED splits our surface into separate triangles and deposits them into a separate folder structure.
Split Geometry divides the geometry into objects that don’t exceed their assigned polygon carrying capacity. The default value is set at 5000.
In the next step, we want to put back together one of the 2 halves of our hood. Therefore, please select the left side of the hood. As an assistance, you can isolate the hood in the renderview by selecting and dragging the group node with the left mouse button held down into the viewport. Additionally, please select in the main menu, under Visualization, the Vertex Face Rendering mode to get a better overview of your geometry.
Now, select the left half of the hood. With the Shift key held down, click the geometry with the left mouse button. Please continue by opening the Material Editor via the Quick Access Bar. Create a new plastic material with the Create menu, by selecting Plastic, in the sub-item Create Material and assign it to the selected surface. To do so, select the freshly created material and call up the Material Editor menu by clicking the material with the right mouse button. With the command, Apply to Selected Nodes, the material can be applied to the selected geometry.
We now want to put together both halves of the hood. Therefore, we select our group node and trigger the Scenegraph menu with the use of the right mouse button. In the sub-item Edit, we, in the lower section, execute the Merge Geometry command. Autodesk VRED automatically adds together the geometry to each two parts the of hood with each the same material assignment. The Merge Geometry command only takes effect on the geometry with triangles in the group which possess the same material.
To illustrate this process to you again, we finally want to combine both sides of our object to one geometry, and thus getting back to our starting point. As previously mentioned, it is crucial that our separated surfaces have the same material assignment, and that the geometry is within a shared group node.
Please select the right side of the hood which still has its original material and please assign it the newly created plastic material. Please drag and drop our plastic material to the right side of the hood to assign the material. Both sides now have the identical material assignment and can be put together with the Merge Geometry command. To do so, we pick the group node in our Scenegraph and call up the Scenegraph menu with the right mouse button. Under the sub-item, Edit, please choose Merge Geometry to combine both sides to one geometry.
In the following, please pull your Root node, using drag and drop, into your renderview. To reactivate the realistic rendering in the viewport, go to the Visualization menu and select Realistic Rendering. Autodesk VRED additionally offers the opportunity to merge surfaces with each other during file import. To illustrate this merge command on import, we use the example file via the File menu, and select Open File to execute the Open command.
We can, after the activation of the tessellation of the parameters, in the Import Options dialog, activate the selection, Merge Geometries.