Working with Objects
The built-in object library may not contain all of the objects necessary for carrying out your project. The program lets you import other objects stored on your disk in the following formats:
- Trimble SketchUP™
- Autodesk 3D Studio (created in the Autodesk® 3ds Max® software)
- Autodesk FBX
- Collada Zipped
- Wavefront OBJ
- Sweet Home 3D
- Google Earth KMZ
- Ogre XML
The Image option listed above does not let you import a 3D model but a regular graphic file. The program will automatically create a 3D Image object from it.
To import an object from a file:
- Select File > Import… in the menu or use the Import toolbar button.
- Specify the format of the file you want to import and select the file.
- Set up the import options, if available.
- The Type and Representation dialog will open up automatically. You can just verify the object dimensions and click OK.
If you are going to import a door, window or staircase, select the proper object type before closing the dialog.
It is possible to open the dialog any time later. For more details, see the Type and Representation section.
A second way to import an object is to drag and drop it from Finder to your project. By using this method, you can bypass all intermediate dialogs and import objects with the default settings.
Imported objects may have references to one or several textures. The program will try to find them in the folder containing the selected file. If a texture is not found, you will be asked to locate it in the Finder. The texture name will be shown at the top of the Open File window. You can also opt to skip opening textures and simply use the materials from the built-in library.
Merge submeshes with similar materials
By merging submeshes, the program can remove excessive details from the object model. This can potentially simplify the model and increase the rendering speed.
This optimization can limit your ability to apply different materials to different object parts. We can learn how this option works with an example of two cubes.
The first cube has different materials on its sides. In other words, it has no similar materials. Turning the option on or off will give you the same result.
The second cube has the same material applied to all of its sides. When the option is off, an imported cube will have the original material on its sides. You will be able to apply another material to any side of the cube. If you import the cube again with the activated option, the imported cube will look exactly as before, but the 3D model will be changed. If you now apply a new material to any object side, all of the sides will change.
Make all surfaces double-sided to avoid invisible surfaces
This option fixes the problem with invisibility of one-sided surfaces.
When you look at a cube, you can see any of its six sides. To visualize them, 3D software creates faces by one per each side. Faces allow the application of a plain color or texture to corresponding parts of an object making them visible. If there is a need to show the cube from inside as well, each side of the cube should have two faces: the inner and outer.
Most of the objects can be previewed only from the outside like a cube. To simplify 3D models of these objects, faces of invisible object parts may not be created. An open box (a cube with one side removed) should have both internal and external faces on all five sides because the internal parts should be visible as well. The lack of faces where they are needed, makes parts of an object invisible.
On the other hand, adding faces leads to increasing the 3D object complexity, which results in increasing the document size. A good practice would be the following. Normally, import objects with the Make all surfaces double-sided option deactivated. If a part of an imported object is invisible, reimport this object with the activated option.
Split Object Instances
The Split Object Instances option can split a compound object turning its parts into separate objects. In your project, an imported object will be added as a group which includes all of the original parts.
Models can be split only when they are made out of several components. For example, some models are composed of several objects (a lamp, a computer, books, etc. on a table). If objects are made up of components, you can split them to remove or rearrange some of these components.
You have an additional option to split all or only identical objects.
The ability to split a model depends on how it was created.
When the Import lines option is deactivated, the program ignores lines. For example, such lines can be created in the SketchUp software using the Line tool. In many cases, the option should be switched off.
The program limits the size of images imported as textures. If an image is larger than the selected value, it will be scaled down. The aspect ratio will be maintained. For example, when you select "1024", you limit the size of the bigger texture side to 1024 pixels.
Higher value let you have high-resolution textures with more details preserved. With lower value, the program will render objects in the 3D view faster. So, you can choose what is more important in your work.