Wrangle x Python book I tried it [1]

What is this?

Distributed at COMITIA115 (2016/01/31 at Tokyo Big Sight) ** Houdini Practical Handbook Wrangle x Python ** (Circle "Magic Distilled Water") http://majou.jp/archives/667/

This is a memo when I tried to work on a Python example sentence.

p.10 "3 Wrangle x Python practice" 3.1 Point movement

Preparation

New scene → geometry node creation

Once inside (delete the original file1) Create grid Create python Connect

setPosition() The example sentence on p.10. I will write in the Python Code column in the Python node

The first two lines were written when the Python node was created, so Only the next 4 lines. (* The first two lines are described on p.6)

python

for point in geo.points():
    pos = point.position()
    pos += hou.Vector3(0,2,0)
    point.setPosition(pos)

This is the only secret that I typed the points of geo.points () to the point and became "Are".

result I moved 2 in the Y direction.

I also rewrite it as follows and play

Rewrite 1

for point in geo.points():
    point.setPosition( point.position()+hou.Vector3(0,2,0) )

Rewrite 2

x = 0
y = 2
z = 0
pos = hou.Vector3(x,y,z)

for point in geo.points():
    point.setPosition( point.position()+pos )

hmath.buildTranslate

p.10 Second example sentence

python

for point in geo.points():
    pos = point.position()
    mtx = hou.hmath.buildTranslate((0,2,0))
    pos = pos * mtx
    point.setPosition(pos)

pos = pos * mtx can be an assignment operator. pos * = mtx

Summary

For the time being, only the Python example sentences on p.10.

Wrangle x Python book, Toranoana seems to be orderable https://www.toranoana.jp/mailorder/article/04/0030/38/99/040030389986.html ~~ It seems to be scarce ~~ <When I confirmed it at the timing of writing [2], it was sold out!

Remarks

Suggestion

Input completion appears in the middle of typing, such as around hou.hmath.b

Function description

When you start typing the function arguments, you will see a description of the function.

print and help

If you put print orhelp ()in Python Code It will be displayed in a separate window called ** "Houdini Console" **.

Please note that if there are too many lines, it will flow. For example, the above figure is an example when help (hou.hmath) is done, but the beginning part flowed and could not be read. (As expected, help is in Python Shell ~)

reference

Vector3 http://sidefx.jp/doc/hom/hou/Vector3.html

Matrix4 http://sidefx.jp/doc/hom/hou/Matrix4.html

setPosition http://sidefx.jp/doc/hom/hou/Point.html#setPosition

hmath http://sidefx.jp/doc/hom/hou/hmath.html

Since the published Japanese documents are not translated into Japanese unexpectedly, it is often quick to go to the head family quietly.

By the way, about Houdini's Python environment I also touched a little here

Python interpreter in Maya, Houdini, blender, Nuke http://qiita.com/it_ks/items/ae1d0ae01d831c2fc9ae#houdini