Use python to render scene in Blender 3D.

The python script is very simple.

I used my scene with Mickey Mouse (my boy like this funny cartoon).

This is the python script.

import bpy
bpy.context.scene.render.use_border = False
bpy.context.scene.render.use_crop_to_border = False
bpy.ops.render.render()
R="Render Result"
bpy.data.images[R].save_render("/home/your_username/test_render.png")

See the output image:

The next source code it's used for border and crop.

Only if you want to use it.

bpy.context.scene.render.use_border = False
bpy.context.scene.render.use_crop_to_border = False

Also you can use this to set resolution percentage.

For example if you want to render just 10% of resolution use this:

bpy.context.scene.render.resolution_percentage =10

Using fnmatch python module ...

The module fnmatch provides support for Unix shell-style wildcards, which are not the same as regular expressions.

Why , because the special characters used are : * , ? , [seq] , [!seq] .

This is default example from fnmach website.

>>> for file in os.listdir('.'):
...  if fnmatch.fnmatch(file, '*.txt'):
...   print file
... 
tableta.txt
verf.txt
a.txt
python-modules.txt
untitled.txt
resetbios.txt
>>> 

Now I want to show you another way to use this module.

Using Blender with multiple objects and python script can be very hard way.

For example if you have many objects or one matrix of objects create manually or with some scripts the named object is like in the next image:

Just use the fnmatch to sort this objects.

>>> import bpy 
>>> import fnmatch

Now get all meshes objects.

>>> all_objects = bpy.data.objects

Put names of all meshes as a list of strings.

>>> list_all_objects= [all_objects[i].name for i in range(len(all_objects))]

Use the python module fnmatch to filter the name of objects.

>>> new_list_objects = fnmatch.filter(list_all_objects, 'Cube.*')]

Now you can use this new list to make some change. I use print to show test the list.

>>> print(new_list_objects)
['Cube.001', 'Cube.002', 'Cube.003'

The goal of fnmatch module in Blender 3D can be use one module to make list of objects and enables searching for files given a file name pattern.

It's two features in one module.

Also this python module can be used to get some

>>> regular_expression_txt = fnmatch.translate('*.txt')
>>> regular_expression_txt
'.*\\.txt\\Z(?ms)'
>>> print(regular_expression_txt)
.*\.txt\Z(?ms)

Just remove \Z(?ms) and use it.

I try to use some regular expression and seam working well.

Simple way to reverse strings

Just see the next source code:

>>> text='0123456789'
>>> reverse_text=text[::-1]
>>> print reverse_text
9876543210
>>> 

Make Newton fractal with python

A fractal is a mathematical set that has a fractal dimension that usually exceeds its topological dimension , see Fractal wikipedia.

Today I used my mind and also my python skills to make one fractal image.

I use Newton's method to make all points and PIL python module to save the result.

Let's see the source code and comments.

from PIL import Image
#size of image
imgx = 600
imgy = 400
#make image buffer
image = Image.new("RGB", (imgx, imgy))

# area of fractal
xa = -2.0
xb = 2.0
ya = -2.0
yb = 2.0

#define constants
max_iterations = 10 # max iterations allowed
step_derivat = 0.002e-1 # step size for numerical derivative
error = 5e-19 # max error allowed

# function will generate the newton fractal
def f(z): return z * z  + complex(-0.31,0.031)

# draw derivate fractal for each y and x 
for y in range(imgy):
 zy = y * (yb - ya)/(imgy - 1) + ya
 for x in range(imgx):
  zx = x * (xb - xa)/(imgx - 1) + xa
  z = complex(zx, zy)
  for i in range(max_iterations):
   # make complex numerical derivative
   dz = (f(z + complex(step_derivat, step_derivat)) - f(z))/complex(step_derivat,step_derivat)
 # Newton iteration see wikipedia   
   z0 = z - f(z)/dz 
   # stop to the error 
   if abs(z0 - z) < error: 
    break
   z = z0
  #I use modulo operation expression to do RGB colors of the pixels 
  image.putpixel((x, y), (i % 8 * 16, i % 4 * 32,i % 2 * 64))
  
#save the result 
image.save("fractal.png", "PNG")

This is the final result of Newton fractal image:

PP 1.6.4 is released ...

The new version : PP 1.6.4 is released and working well.

What is PP python module?

PP is a python module which provides mechanism for parallel execution of python code on SMP and clusters.

SMP - systems with multiple processors or cores;

clusters - computers connected via network;

Read more Parallel Python.

Using Flask to build websites in Python.

The python module Flask is a small web framework.

Install the module using pip.

(my_new_env)[free-tutorials@free-tutorials ~]$ pip install Flask
Downloading/unpacking Flask
  Downloading Flask-0.9.tar.gz (481kB): 481kB downloaded
  Running setup.py egg_info for package Flask
    
    warning: no files found matching '*' under directory 'tests'
    ...
    ...
Successfully installed Flask Werkzeug Jinja2
Cleaning up...

Create the next python script and save as : flask-web.py .

from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello World!'

if __name__ == '__main__':
    app.run()

Run the python script:

(my_new_env)[free-tutorials@free-tutorials ~]$ python flask-web.py 
 * Running on http://127.0.0.1:5000/
127.0.0.1 - - [25/Jan/2013 00:10:35] "GET / HTTP/1.1" 200 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /favicon.ico HTTP/1.1" 404 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /robots.txt HTTP/1.1" 404 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /favicon.ico HTTP/1.1" 404 -
127.0.0.1 - - [25/Jan/2013 00:10:36] "GET /robots.txt HTTP/1.1" 404 -

You will see something like this:

Also you can try the quickstart tutorial here.