This is the second article in a series of articles that introduces Blender 2.5 for a classroom environment.
For those of you that don’t know Blender, it is high on my list as being my most favored open source software that can be downloaded at no cost over the Internet.
Blender has a reputation as somewhat of a challenge. Its interface in the past has been complicated and frustrating. I think this is a distant memory with the release of Blender 2.5! I highly recommend interested teachers to investigate how this free software can be utilized in your classroom.
Recently I conducted a series of one-lesson workshops with a group of high school students in order to introduce them to 3D Modeling and Animation using Blender. I started off slowly (even though some students still were determined to move at lighting pace through the program and who am I to stop them). Below are some of the introductory workshops that I conducted in order to introduce them to some of the basic mathematical concepts and functions in Blender.
After I had explored these concepts I had them render and save a 2D image of three different geometric shapes that varied in scale, location and rotation. This particular activity introduced them to the following ‘Hot Keys’ in Blender.
- R = Rotate
- S = Scale
- G = Grab
As an extension the following day I introduced them to the basic animation functions in Blender and the concept of Key Frame animation, which is the primary method of computer animation. For those of you that are not familiar with the concept of Key Frames I’ll explain.
The standard definition of an animation is a sequence of 2D or 3D images that are shown rapidly in order to achieve the illusion of movement. Images used for motion pictures are referred to as a frame. When we make a film, the camera is recording 24 frames per second (24fps). As a default, Blender animations also contain 24 frames per one second of rendered animation. Before the advancement of digital technologies an animator at Disney would have to draw every single one of these frames! However, with Key Frame animation we only have to insert the two frames in a single sequence of movement. Lets imagine we are creating an animation of a ball falling from the air. In order to animate our ball we first have to insert the starting location of the ball (which is probably somewhere above the ground). This is our first key frame. The second key frame is our end location (which is probably the ground). The computer then inserts all of the key frames needed. So, imagine we are creating a five second animation of a ball falling from the sky. We insert our first key frame referenced above as the first frame in our sequence, we then add the second key frame (usually on a timeline) at 120 frame (at 24fps there are 120 frames in a five second animation). The computer will add the other 118 frames (images) needed to provide the illusion of movement. This is the basic concept of key frame animation.
In order for the students to demonstrate this concept I had them animate their three basic geometric shapes that had been created in the previous workshop. With an understanding of how to scale, rotate and relocate objects I challenged the students to animate their three shapes in three different ways, while introducing them to another Blender key frame:
- I = Insert Key Frame (they can then select to insert a rotation, location or scale).
Despite the fact some students still appeared a little nervous with this technology, they were more willing to participate in this activity and seemed to be pleased with their outcomes. I noticed some students felt a need to insert multiple key frames, which over complicated their project. I think this was the result of an experience with another software, which needed students to literally draw every frame in their animated project rather then a fault of the activity. At the close of the lesson I felt most students eventually achieved the concept of Key Frames, but some needed that second day in order to develop confidence with the Blender interface, which nearly all students achieved after only three days. The magic of creating an animation was very exciting for the students, and appeared to increase their engagement in this digital medium.
Once students have a basic understanding of key frame animation, and how to insert key frames into the Blender timeline window, I am confident that most students will be able to animate in Blender. This means that a teacher can focus on developing 3D modeling skills, rather than animation skills in order for students to produce 3D animations in Blender.