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Animate strange attractor via Python in Blender 2.6

Example how to use bpy.app.handlers.render_pre.append() to animate meshes

Author: Berlin, Date: 07. Feb. 2012

Download:

anim_attractor.blend (07. Feb. 2012)

1) Click 'Run Script'
2) Select the Output
3) Click 'Animation'

Attention: the script-window in Blender 2.61 will freeze after rendering (I do not know why, maybe a bug), so you have to restart if you want to do a new animation/rendering.

Python script:

This code is a short example how to rotate a simple cube, frame by frame, without using keys.

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  1. import bpy
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  3. try:
  4.     bpy.data.objects['Cube']
  5. except:
  6.     bpy.ops.mesh.primitive_cube_add(location=(0, 0, 0))
  7.     cube = bpy.context.scene.objects.active
  8.     cube.name = 'Cube'
  9.  
  10. i = 0
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  12. def move_cube(scene):
  13.     global i
  14.     cube = bpy.data.objects['Cube']
  15.     cube.rotation_euler = (0, i/10, i/10)
  16.     print("Callback: "+str(i+1)+", Frame: "+str(scene.frame_current))
  17.     i = i+1
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  19. for i in range(len(bpy.app.handlers.frame_change_pre)):
  20.     bpy.app.handlers.frame_change_pre.pop()
  21.  
  22. bpy.app.handlers.render_pre.append(move_cube)
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Also take a look at the Blender Add-On to easily create Peter de Jong, Clifford and Lorenz attractors.

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Analog SLR viewfinder compositing in Blender 2.6

Node Tree for Blenders compositor to simulate an old non-autofocus SLR viewfinder focusing screen

Author: Berlin, Update: 29. Jan. 2012


(Click to watch the short demo video of the first test, using a scene from 'Vivre sa vie' Jean-Luc Godard 1962 with Anna Karina)

My old Pentax MX SLR was the reference. The compositing in Blender 2.6 is not perfect (can never be perfect) but it is very close to the real viewfinder.
Btw.: Buy film not megapixels (tokyocamerastyle.com)

Download:

viewfinder_final.blend 3.8 MB incl. all Images (29. Jan. 2012)

Node setup info screenshot

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Stereoscopic Rendering in Blender 2.6

How to implement an off-axis camera to produce correct stereo pairs via Python Add-on in Blender

Author: Berlin, Update: 18. Nov. 2011

Since there is no stereoscopic camera in Blender, I decided to write a python script to implement an 'Off-Axis' stereo camera. This script sets the 'Stereo Window' or zero parallax in Blender and not via postproduction. It creates a parallel off-axis camera rig, the best way to produce stereo pairs without vertical parallax. You can use Blenders Node Editor to control the left and right camera render results and combine them to a Side-by-Side or Anaglyph image.

Download:

Download Version 1.6.6 (18. Nov. 2011)
Python script 53KB for Blender 2.6

Video tutorial (youtube.com)
Download the original H.264 video here

Extra video:
How to render a stereo Side-by-Side animation (youtube.com)

Mathematics:

For those who are interested in off-axis calculation and how to build the 'stereo comfort zone', here are some formulas.

1. Calculating off-axis shift (delta) in pixel:

b = stereo base (horiz. separation of left and right camera)
w = render width in pixel
f0 = focal distance to zero parallax (stereo window)
FoV = horiz. Field of View (camera angle)

2) Calculating max. disparity (disp) in pixel at near- and far-plane (simple sine rule):

theta = max. parallax angle, given by the user (default 1.0°)
vdist = distance between viewer and projection screen
ppi = Pixel Per Inch of the projection screen

3) Calculating distance (pdist) to near- and far-plane to get the 'stereo comfort zone':

b = stereo base (horiz. separation of left and right camera)
delta = off-axis shift of the first formular in pixel
disp = max. disparity at near- and far-plane (2nd formular) in pixel (disp is for Nearplane (+) positive and for Farplane (-) negative)
FoV = horiz. Field of View (camera angle)

4) Calculating the 'Toe-In' angle in degree for the converge camera rig:

b = stereo base (horiz. separation of left and right camera)
f0 = focal distance to zero parallax (stereo window)

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Strange Attractors in Blender 2.6

A simple Python Add-on to create diffrent shapes of beautiful 'Peter de Jong', 'Clifford' or 'Lorenz' attractors.

Author: Berlin, Update: 09. Jul. 2011

Download:

Download Add-On v0.3 (09. Jul. 2011)
Python script 12KB for Blender 2.6.0

Video tutorial (youtube.com)
Download the original H.264 video here

Note: Instead of using 'Halos' to visualize every single point of the attractor cloud in Blender, you can also use a 'Wire' material with zero-length edges to get a nicer and sharper result. How to do this: 1. Select the attractor, 2. Switch to 'Edit Mode' (Tab-Key), 3. Extrude the vertices by pressing e-key and don't move the mouse, just hit Enter, 4. Go to the material panel and select 'Wire' (and change colour, emit etc. if you want), 5. Optional: uncheck Anti-Aliasing in the render panel

Peter de Jong in Python:

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  1. itr = 0
  2. while itr < MAX:
  3.     new_x = math.sin(a*y)-math.cos(b*x)
  4.     new_y = math.sin(c*x)-math.cos(d*y)
  5.     x = new_x
  6.     y = new_y
  7.     # save (x,y) coordinates into array
  8.     itr += 1

Example

Clifford in Python:

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  1. itr = 0
  2. while itr < MAX:
  3.     new_x = math.sin(a*y)+c*math.cos(a*x)
  4.     new_y = math.sin(b*x)+d*math.cos(b*y)
  5.     x = new_x
  6.     y = new_y
  7.     # save (x,y) coordinates into array
  8.     itr += 1

Example

Lorenz in Python:

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  1. itr = 0
  2. while itr < MAX:
  3.     new_x = x + h * a * (y - x)
  4.     new_y = y + h * (x * (b - z) - y)
  5.     new_z = z + h * (x * y - c * z)
  6.     x = new_x
  7.     y = new_y
  8.     z = new_z
  9.     # save (x,y,z) coordinates into array
  10.     itr += 1

Example

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Panorama view from a short trip to the Baltic Sea

In this image, the tree is cut in half, but I like this imperfect result more than a boring perfect photomerge.

Author: Berlin, Update: 03. Apr. 2011

Sound example of the Baltic Sea: sound.mp3  HiMD record, stereo 8:42 min.

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Stereoscopic Rendering in Blender 2.49

How to implement an off-axis camera to produce correct stereo pairs in good old Blender 2.49

Author: Berlin, Update: 24. Sep. 2010

There are actually three old scripts for Blender 2.49b. The first verison (see screenshot below) is not that easy to use but gives the best results. The alternative script 0.4 changes the 'shiftX' camera parameter to set the 'Stereo Window' in Blender. This script is much more comfortable to use. Unfortunately the 'shiftX' parameter in Blender 2.49 only accept values between -2.00 and 2.00 (with only two decimals), but the script calculates the shift in pixel and a relative value with six decimals, which is more accurate. Due to this mismatch the result will never be perfect. The third script adds a simple 'Toe-In' Camera Rig (Note: 'Toe-In' produces vertical parallax).

Download:

1) Python Script for Blender 2.49 (best results)
Download: BStereoOffAxisCamera_1_5.py
Watch: Video Tutorial (Vers. 1.3)

2) ShiftX Version (more comfortable to use)
Download: BStereoOffAxisCamera_0_4.py
Watch: Video Tutorial (Vers. 0.3)

3) Simple 'Toe-In' Version
toein_stereo_camera_249.py

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Haus Zwei im November

Old semester work inspired by Michel Gondry's Sugar Water videoclip for Cibo Matto

Author: Berlin, Date: Unknown

von: Ajaz Ansari und Sebastian Schneider
Ort: Siegmundshof Berlin Haus 2
mit: Qian Wang

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