Posts filed in ‘blender’
Circular Escalator
After seeing this picture on Flickr:
I decided to see if I could model the bastard child of an escalator and a circular staircase:
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I think that it works pretty well.
Attractors
I’ve recently been playing with Chaoscope, software for rendering 3D strange attractors. Here is an example of a render of a type A polynomial as rendered by Chaoscope:
If you are interested in replicating this image, use the following factors: p0=0.271, p1=1.594, p2=1.122.
While the images that Chaoscope renders are quite interesting, they are based around an orthographic camera model - there is no vanishing point perspective. I decided that I should try to replicate these attractor systems in Blender. I modified some python code that I found here with the formulas that Chaoscope uses to produce this:
Later I want to modify this by adding more of the formulas that Chaoscope uses, especially the “Unravel” one, and to animate, both by moving through space, and by changing the attractor’s coefficients through time.
Hell and Halos, a Random Walk
I’ve spent a lot of time trying to come up with simple cloud systems to use with Blender. This is the result of one test, in which I used the Python scripting interface to create a model using a random walk.
In a random walk you start at the origin and select a random direction to move one space. Repeat. After many thousands of repetitions I was left with a cloud of vertices. I applied a red halo material to the cloud model and rendered.
The very first render produced a very pleasant result. As a still image. Right away I tried to animate this scene, as a single frame renders very quickly. Unfortunately, since all the vertices are placed at regular intervals, once the image moves, artificial structure becomes very easy to see.
I may have to try this again with a random jump between steps in the random walk. Another challenge for making this a good cloud material is to figure out a way to animate the structure of the cloud itself.
How to Construct a Tetrahedron in Blender
This tutorial requires basic knowledge of Blender.
Background
Blender’s three-dimensional rectilinear grid allows for easy creation of cube-based objects. But what do you do if you want to create a tetrahedron, a regular polyhedron with four equilateral triangle faces? My initial attempts at this involved trying to create one face on the X-Y plane and rotating a copy up. This turned out to be a lot more trouble than it’s worth because you have to deal with some very specific angles.
After playing with a magnetic toy in the shape of a tetrahedron I realized that it could be inscribed neatly in a cube, with each of its vertexes in a corner of the cube, and each of its edges running along the diagonal of one of the cube’s faces.
In short the coordinates for the vertices of a tetrahedron are:
(+1, +1, +1)
(−1, −1, +1)
(−1, +1, −1)
(+1, −1, −1)
Constructing the Tetrahedron
Create a cube, switch to vertex select mode and rotate the scene so that you can see and select any of its vertices. The image below already has a tetrahedron inscribed in it which should help you locate the new faces you will add. Each vertex of the cube is labeled “A” to “H”:
Select A, D, F. Press [F] to create a face.
Select D, F, G. Press [F] to create a face.
Select A, F, G. Press [F] to create a face.
You now have a tetrahedron inscribed inside the original cube. Let’s cut away the cube:
Select B, C, H & E. Delete these vertices.
You are now left with a tetrahedron:
