CS 424: Computer Graphics, Fall 2015
Blender Lab 2: Blender Modeling
This is the second of three labs that are planned using the 3D modeling and animation program, Blender. The assignment for this lab involves using Blender's modeling capabilities to design custom objects. At the same time, you should get more comfortable and skilled at using Blender.
Your Blender work for all three labs should be submitted in a folder named blender inside your homework folder. For this lab, you should submit a copy of your completed Blender file. You should also submit at least one rendered image of your scene. Use file names that will make them easy to identify, such as blender2.png or modeling.blend. I will grade all Blender work at the same time, a week after the third Blender lab.
Using Modeling Tools
There are very few instructions for this lab. You can start with Blender's default scene or, if you prefer, with a copy of the empty stage from last week's Blender lab. You will create a scene containing several objects that you have created using some of the many modeling capabilities that Blender makes available. Some of the techniques were demonstrated in class on Friday. Blender modeling is covered in Section B.2. That material is not repeated here, but you will need to be familiar with that section to do the lab.
You should make several objects; a minimum of four that require some non-trivial modeling work (and more if you want!). The requirements for the objects are:
- One of the objects must be a "hierarchical" made up of several sub-objects that are joined into a unit using parenting. To parent one object to another, select the child object, then right-click the parent object to add it to the selection, and hit Control-P; select "Object" from the pop-up menu. (By the way, you can clear a parent relationship by selecting the child object and using ALT-P.) Parenting could be used, for example, to attach the wheels to a car or the propellor to an airplane or the rings to a model of Saturn.
- One of the objects must be created using extrusion and the subdivision surface modifier. Use extrusion to create a boxy, approximate shape, then apply the modifier. Usually, the best starting point for extrusion is something simple like a cube or a mesh circle.
- You should use either Text or a Bezier curve to make a 3D object. The 3D effect comes from adding thickness to a 2D object (For a curve, remember to set the original curve to be 2D.) Blender can use a variety of different font files. To make it easy to find the files, I put some in the folder /classes/cs424/fonts-for-blender.
- You should also do something else. For example, use a different modifier. (Maybe use an Array modifier to display multiple copies of an object, for example.) Or do something fancy with a texture, such as a bump map or using the texture to modulate the transparency or reflectivity of a surface. Or learn how to use Sculpt mode. Or find some interesting feature that I don't know about.
You should also make some kind of base that your objects can sit on (or fly above). It would be nice to do this by warping a plane with a Displace modifier, or proportional editing, or Sculpt mode. However, a simple cube or cylinder could be OK if your other objects are complex enough. (If you want to warp a plane to make the landscape, remember to subdivide it six or seven times first, since you need a lot of vertices.)
You are not required to make a realistic scene, but some degree of realism might be nice. You might build houses or snowmen or trees. You might put a sign on the hills like the famous Hollywood sign. You might have an airplane or a hot-air balloon or some clouds flying above the landscape.
Lights and Camera
The scene from the previous Blender lab used two Point lights. (Lights are called "Lamps" in Blender.) In this lab, you are responsible for illuminating the scene. You need several lights, but not usually more than three, to get nice-looking lighting. One of the lights that you use should be a directional light (called a "Sun" in Blender) or a a Spotlight. Suns and spotlights have to be aimed, which can be difficult to get right. Remember that you can use the "Track" feature to aim a light at one of the objects in the scene. (Select the light, then shift-right click the object and hit Control-T; select "Track To Constraint" from the pop-up menu.) Please don't use extreme colors for the lights. Maybe a little yellow for daylight, or a little red for sunset...
You will also need to set up the camera with a good view of the scene. Again, you can use tracking to aim the camera at an object. Also useful is the fact that you can drag and rotate the camera when the display is in camera mode (Numpad-0). In that view, the camera is represented by the rectangle that bounds the view through the camera. You can select the camera by right-clicking that rectangle. Then you can use the G and R keys to transform the camera. Unfortunately, you can't scale the camera. To increase the apparent size of an object, you have to move the camera closer to it.
If you want to take several pictures of your scene, you can use several cameras. You can add additional cameras to the scene, just like any other kind of object. Only one camera is active at a given time. The active camera is the one that is used to render the image. You can make a different camera active by right-clicking it, then hitting Control-Numpad-0.