5.5. Tutorial: Editing the geometry in an external application

Starting Point

Load in your photographs, mask them and generate a wireframe model. In our example we will build a model of a concave shell.

Step 1

Try optimising the mesh using the Surface Wizard which is launched by clicking on the Generate surface... button. Select the "Optimise Surface" option and close the dialog when happy with the improved mesh.

TIP:	It is a good idea to decimate the mesh a little using the slider before exporting as this will help 3DS Max perform more robustly when performing certain operations such as Boolean operators.

Step 2

Export the mesh by clicking the Export model... button. Select 3D Studio Max Object file type and choose a suitable 3DS filename and directory. Do not close 3DSOM Pro.

Step 3

Launch your preferred 3D modelling package. Most packages should support the 3DS file type. Import the 3DS file you just saved.

Step 4

You can now edit the mesh using all the available modelling tools. Make sure the result is still a closed triangular mesh to allow import into 3DSOM Pro.

In our shell example we wish to hollow out the concave region of the shell. We will use boolean operators to achieve this. One idea is to use a cloned copy of the shell displaced slightly to "hollow" out the required concave region. However in this case things are slightly complicated because there is an overhang which would also be removed (see Figure 5.5.3).

Instead, we need to create a new version of the shell but with the "overhang" region removed. Go back to 3DSOM Pro and edit the mask for the front view looking into the concavity. Cut away the overhang region (see Figure 5.5.4) and regenerate the optimised geometry (shown in Figure 5.5.5). Make sure you revert this mask before texturing.

Load in this modified wireframe into your 3D modelling package. Now make the modified object slightly smaller and offset a little outwards from the original. Then using a boolean operator hollow out this region (using the "A-B" operator) to start to create the concave shell shape.

Now we can hollow out the region behind the overhang. Import another copy of the original shell. Reduce in size slightly and adjust the position so that this object does not touch the overhang. Now hollow out this additional "inside" region using another boolean operator.

Step 5

When you are happy, export the edited mesh as a 3DS file on top of the original 3DS file or in a new file if you prefer.

Step 6

Go back to the 3DSOM Pro application with the project still loaded. Import the edited mesh using the File > Import... menu item.

You can now use all the 3DSOM Pro tools including fitting a subdivision surface representation (using the Surface Wizard) texturing (using the Texture Wizard) and texture editing. Finally, the model can be exported in the desired format.