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vineri, 13 august 2010

OpenGL and Python - GLSL example

Today I played a bit with GLSL.
Here is the final result in the image below:

The source code used by me:

vertex shader
varying vec3 normal;
void main() {
  normal = gl_NormalMatrix * gl_Normal;
  gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
 }
fragment shader
varying vec3 normal;
void main() {
 float scale = 1.0 / 10.0;
 float frx = fract(gl_FragCoord.x * scale);
 float fry = fract(gl_FragCoord.y * scale);
 gl_FragColor = vec4(frx,fry,0.0,1.0);
 }

joi, 12 august 2010

PyOpenGL - first lines of code.

What is the best way to write the first line of code on pyopengl ?
Please see below :
Python 2.6.4 (r264:75706, Jun  4 2010, 18:20:16) 
[GCC 4.4.4 20100503 (Red Hat 4.4.4-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from OpenGL import platform
>>> dir(platform)
['CurrentContextIsValid', 'GL', 'GLE', 'GLU', 'GLUT', 'GLUT_GUARD_CALLBACKS', 'GetCurrentContext',
 'OpenGL', 'PLATFORM', 'PlatformPlugin', '__builtins__', '__doc__', '__file__', '__name__', '__package__',
  '__path__', '_load', 'baseplatform', 'copyBaseFunction', 'createBaseFunction', 'createExtensionFunction',
   'ctypesloader', 'getGLUTFontPointer', 'glx', 'os', 'safeGetError', 'sys']
>>> gl=platform.OpenGL
>>> print gl

>>> glCreateShaderObjectARB = gl.glCreateShaderObjectARB
>>> glShaderSourceARB = gl.glShaderSourceARB
As we can see, is simple to start it.
Just use gl.function_opengl.
You can see more examples here.

luni, 19 iulie 2010

Sunflow rendering on Fedora 13

How to install Sunflow ?
It's pretty simple just download the zip archive from here.
Unzip and edit the sh script sunflow.sh
from the sunflow folder.
By default the script is:

#/bin/sh

mem=1G

java -Xmx$mem -server -jar sunflow.jar $*

If we run this script will have this error :
$ sh sunflow.sh 
Invalid maximum heap size: -Xmx1G

Could not create the Java virtual machine.

The solution is:
$ whereis java
java: /usr/bin/java ...

Now change the script :
#!/bin/bash
/usr/bin/java -Xmx1024M -server -jar sunflow.jar $*

And run it ...
$ sh sunflow.sh 

The result is :

duminică, 18 iulie 2010

Blender 3D - ISSUE 28: Blender 2.5

As you know the magazine Blender Magazine is a magazine known to those who use Blender 3D software.
The title of this magazine is "Blender 2.5. In this issue we find some interesting articles related to version 2.5.
However I expect some to be more specific. I expected to find some more specific tutorials.
New version 2.5 has new tools and hardware required. For this reason I wanted to see something more complex.
The magazine comes with sample files. However it seems that the magazine is a success.

FEATURED CONTENTS :
Articles/Tutorials on Creating 3D contents using Blender 2.5
I love my Bubble
Up to Speed
Blender 2.49 Scripting (Book Review)
High resolution rendering @ speed of the light
and more ...
The issue and files can be found here.