Tutorials

By Tim Wesoly, developer of Qubicle Constructor
What you need: Qubicle Constructor v1.08+ Master or Education Edition

Qubicle’s OBJ exporter offers a lot of settings. In this brief tutorial you will learn how to prepare your models and setup the exporter according to your needs.

Downloadable resources for this tutorial

To make things clear faster I made a package including a sample model and the various export results. You can download this package here:

Download qubicle_tutorial_resources_obj_export.zip

How to export as OBJ

To export a selection of matrices follow these steps:

• In model edit mode select the matrices you want to export
• Choose File > Export Selection from the main menu
• In the save dialogue, type in a file name, select OBJ Wavefront as filetype and click on save
• In the OBJ export settings dialogue that pops up change the settings as needed (discussed next) and click on OK to export

The OBJ export settings dialogue

Material types

The Qubicle OBj exporter currently supports two different material types – simple texture and multi material.
The main difference between the two modes is the way the color information is provided.
For both material types the exporter creates a colormap of all used colors in the exported objects.

The simple texture type creates a single material that uses one .png image file as a texture. The texture is quite small because it contains only one pixel per color of the colormap.

The multi material type creates one material per color of the generated colormap. So in the case of our sample model which uses 5 different colors, 5 materials are created.

In most cases the simple texture material type is the best choice because the material library of your importer software isn’t getting filled with countless materials. Use the multi material type if you want to handle each color individually in your importer software, let’s say by adding textures or changing the opacity.

Grouping

To change the way the exported faces are grouped use the grouping setting. Faces can be grouped in 3 different ways: “Model”, “Matrix” and “Cube”. By setting Grouping to “Cube” every visible cube is exported as a single object. If you use “Matrix” each of the selected matrices becomes an individual object. “Model” combines all faces to one single object.

“Remove lamina faces” and “Remove completely surrounded cubes”

“Remove lamina faces” and “Remove completely surrounded cubes” are settings that optimize the mesh in a way that the amount of exported faces is reduced significantly.
Lamina faces are those faces that are glued together when two cubes are lying side by side. These faces are in most render setups invisible and can therefor be removed. Always leave this box checked unless your “Grouping” is set to “Cubes” and you want keep your cubes intact.
Checking “Remove completely surrounded cubes” is the same as applying a hollow modifier before exporting, so every inner cube is removed. If you have checked “Remove lamina faces” completely surrounded cubes are automaticallly removed. This setting is only usefull when you have set “Grouping” to “Cubes” and “Remove completely surrounded cubes” unchecked.

Move to world origin

Checking this setting translates the exported data in such a way that the center of all faces is lying in world origin. If you export a scene in multiple smaller parts leave this unchecked and the objects are exactly where you placed them in Qubicle Constructor.

Naming conventions

The exported objects and materials are named in a determinated way. This helps a lot if you export a scene in smaller parts or if you reimport objects (most software replace objects with the same name during the import process).
Materials of a multi material are named with “color_” plus the hex value representation of the color. For examaple a pure red would be named “color_ff0000″
The material of a simple texture is called filename + “_simpletex”. If you export to file called “chair.obj” the material is named “chair_simpletex”.
Objects are named “m_” + filename + “_” + an index starting with 0. So the second object of “chair.obj” would be called “m_chair_1″.

Final tips

Always fill all hollows of the matrices before exporting (use the fill hollow tool in slice edit mode). This will reduce the number of exported data significantly when “remove lamina faces” is checked.

When importing to Unity3D set “normals” to “calculate” in the fbx importer section.