tiistai 21. joulukuuta 2010

Using threads in Blender game engine

I just made an experiment of using threads in Blender's game engine. Even though using threads in Python does not necessarily make code any faster (see GIL), in this case using thread(s) has a really big difference.

AFAIK, rendering and execution of python scripts are running sequential in BGE. This is a bad thing if you have to make some heavy lifting in the script. Whole game engine have to wait until the job is done ruining your FPS. By using threads, the heavy lifting can be done parallel (or at least semiparallel) to main rendering loop.

The script can be found from Blenderartists.

maanantai 20. joulukuuta 2010

Towards Blender 2.55

I had a little break from Blender but now its time to go back and see what devs have been doing. I just converted my old pyramidaze script for 2.55. It is REALLY simple but it was my first python script back in 2006 :)

It just iterates through selected faces of the object and adds a pyramid top of them (see image above).

Here is 2.55 version:
# - This script adds a "pyramid" over every selected face
# - Open this file in the Blender's text window
# - Select faces
# - set settings (see below)
# - run script (Alt + P)
# there is nothing special in this script but it shows how to iterate 
# through all faces in selected object, how to get normal and how to 
create new mesh object.
# Feel free to use this script any way you like, I'm sure this is very useful ;)
#Ari Hayrinen 29.11.2006 
# updated for Blender 2.55 20.12.2010
# - GUI 

import bpy
import mathutils

# settings
py_height = 1       # pyramid height if use_area is 0, negative value inverts pyramid
use_area = 1        # if 1, uses face area as pyramid height
area_multi = 1      # multiplier for face area, negative values inverts pyramid


objekti = bpy.context.active_object
scene = bpy.context.scene

# list for new faces
coords = []
faces = []

# counter so we know where to add new faces 
verts = 0  
vertices = objekti.data.vertices

# let's go through all faces in selected object
for face in objekti.data.faces:
#use only selected faces    

if face.select:

center = face.center

#number of vertices
vco = len(face.vertices) 

if use_area:
py_height = face.area * area_multi

#multiple normal with pyramid height and add result to the center of the face
center.x = center.x + face.normal[0] * py_height
center.y = center.y + face.normal[1] * py_height
center.z = center.z + face.normal[2] * py_height

#create vertices 
verts +=1

for i in range(vco):
verts +=1

#create triangles
cco = vco + 1                        # number of created vertices
for j in range(vco):    
if j < (vco-1):
faces.append([verts-cco, verts-(cco-(j+1)), verts-(vco-j-1)])
faces.append([verts-cco, verts-(cco-(j+1)), verts-(cco-1)])

# Create new mesh block and add faces to it
mesh = bpy.data.meshes.new('myMesh')


new_obj = bpy.data.objects.new("koe", mesh)

new_obj.location = objekti.location