Blender 3D 2.49 Scripting Book Review

Blender 2.49 Scripting

Personally I have been searching for books and tutorials online and anywhere I can on scripting…Finally I have found one.

Blender 2.49 Scripting is another Packt Publishing Book. It’s written by Michael Anders, a guy who studied Chemistry and Physics. You would never guess that he would write a book on Blender especially scripting although he admits to being naïve about blender.

The book has 269 pages and divided into 9 chapters.

CHAPTER 1

In this chapter we explore how to use in-built blender and python in scripting. Questions such as:

•       How to use built in Blender

•       Writing a simple script that adds an object onto a scene.

•       How to register a script.

We get a brief description of how to use basic scripting in blender and using tools that I am sure many have wondered about.

•       There is a continuous exploration on modules.

•       Familiarizing yourself with the built in editor.

•       Integrating a script into blenders’ menus/help system.

•       Adding different kinds of objects into a scene.

CHAPTER 2

We get to learn how to create creepy crawls from an application that you are shown how to make. There’s nothing I enjoy more than building something from scratch and in this section we get to learn to do that.

We get a step by step process of creating body parts of crawling creatures.

What excited me also was the adaptability of blender to many functions when using scripting. I have always wondered how 3d bar charts were made and animated and I found my answer here:

We import a spreadsheet in csv format and then automating the creating and rendering of the bar chart and a detailed process is explained on how to arrive at an automated bar chart. I got to admit that I barely understood what I was looking at but then again it’s not a one night lesson. After taking a shot at it a number of times I’ll get somewhere.

The whole book looks like algebra if you were to scroll through it fast and if you never liked math in high school you might feel a bit …….aarrggghhhh. Take a closer look… it’s not algebra.

On many occasions blender is used in Architectural visualization although it’s not really a CAD program. I use it too for that. After giving up on character modeling because I am just too impatient, architectural modeling just took my time instead… [It’s funny, I can spend hours on a building but even an hour on a character is just too much for me]

CHAPTER 3

This chapter delves into vertices and how to ease your work of dealing with large numbers of vertices by assigning them to vertex groups and exploring the different areas where vertex groups can be applied like in dealing with armatures and modifiers and also applying color and materials to different vertex groups and leaving others. The explanation is pretty straight forward despite the fact that it’s scripting we are learning here and we have examples to help us along understand the different segments in a chapter in the whole book.

Modifiers can and cannot be affected or used together with modifiers:

Displacement modifier can work with vertex groups but Array modifier cannot work with vertex groups.

The chapter goes on to cover engraving text onto a mesh and converting the whole thing after engraving to mesh and also a simple rigging experiment of a clock.

CHAPTER 4

This chapter is about defining complex relationships between animated objects by using py-drivers. We learn how to define constraints that may be used just like the built-in constraints.

Blender being a complex system, we are made to understand the concepts involved in python scripting.

Understanding: IPOs

Constraints and the differences between the drivers.

Programming with Constraints and IPOs.

Pydrivers and Pyconstraints.

CHAPTER 5

Acting on frame changes, as in setting up scripts to run automatically after certain occasions…I got more and more excited as I moved from chapter to chapter. The idea of making something appear or disappear in 3d without enlisting the hell of aftereffects or other effects programmes is pretty cool. We are given an example of fading an object from black to white.

CHAPTER 6

Chapter 6 is about shapes, keys, IPOs and curves….we explore:

Defining of IPOs

Defining shape keys on a mesh

Defining IPOs for those shape keys

Pose armatures

Group changes in poses into actions-we are given an example of a cartoon character swallowing food and the peristaltic movements that follow. It would be hard to achieve that by simply using shape keys….so how do you do it?

One exciting segment covered is about synching keys to sound that I learned to do in 3dmax but didn’t know how in my adopted software. How to make speakers reverberate according to the music.

CHAPTER 7

In most occasions I have had difficulty achieving the level of texturing that I want although in most occasions good results are still achieved. In advanced level of texturing of using nodes…pretty cool stuff if you know what you are doing because you have complete control over the textures. Here we have Pynodes….we basically use scripting to achieve the level of texturing desired.

In this chapter we learn:

How to write Pynodes that create simple color patterns.

Writing Pynodes that produce patterns with normals.

Writing animated Pynodes.

Writing height and slope dependent materials.

Writing to create shaders that react to the angle of incident light.

We explore how to form realistic rain patterns, ripples, bubbles.

Exciting stuff!!

CHAPTER 8

Chapter 8 is basically about rendering and image manipulation. Rendering here is automated. You can render individual and frames as well as animations and this would save what would otherwise be tedious work. Cameras have been a bit difficult for me at least when it comes to getting that right angle…I spend a lot of time trying to get that right angle and it’s stressful. We get to learn how to render something using scripting from different views and combining all the views into one image using blender’s image manipulation capabilities and an external module called PIL [Python Imaging Library].

As we move along, we come across rendering Billboards.

Billboards are a technique used to apply  a picture of a complex object onto a simple object such as a single square face and replicating the object as many times as needed. This technique is fairly easy to learn and saves a lot of rendering time and the results will be fairly realistic depending on where the objects are placed preferably in far or middle distance.

CHAPTER 9

Expanding your Toolset…..this chapter is basically about making it easier for a learner to understand Blender Scripting. The chapter covers:

•       Listing and archiving assets such as image maps- Images textures that are no longer in use can be archived and stored in a zip file creating order in your system.

•       Publishing rendered images using FTP [File Transfer Protocol] – Meaning we can save a rendered image in a remote server and remembers the server name and [optionally] the password.

•       Extending the functionality of the built-in editor with regular expression searches

•       Speed up computations by using Psyco- A just-in-time compiler

•       Adding version control to your scripts with subversion.

This book won’t be complete without information on where to go to get information on relevant Blender subjects. We get useful tips on how to go about getting information from the internet and forums about Blender. Most questions asked have been asked before and searching forum archives or the web extensively will get you he answers required because in some occasions some questions are not answered because they have been covered before.

Below are links provided in the book?

General Blender-related forums and blogs

Blender’s home page is an important source of information and the following pages should be considered a must read:

• www.blender.org: The home page with news on Blender developments.

• wiki.blender.org: The wiki that contains the manual, tutorials, and links to resources.

Some general Blender-related forums are worth noticing as they attract the attention of a large part of the Blender community:

• www.blendernation.com: This site tries to be the central hub of all Blender-related news and succeeds quite well at it. Its RSS feed is a useful addition to your browser navigation bar to stay up-to-date.

Python programming

This section lists some general Python-related resources. Blender scripting resources are listed in the next section.

• www.python.org: It’s the main site and very well organized, nevertheless some main sections deserve to be mentioned separately here.

• www.python.org/download/: Download your full Python distribution here if you do not already have it installed or if the installed version doesn’t match Blender’s built-in version exactly.

For newcomers and seasoned programmers alike, the following pages offer some useful tutorials on Python in general and some ‘how-tos’ on specific subjects. All the articles on these pages have a fairly low learning curve:

• docs.python.org/tutorial: It is especially worth reading for people experienced in other programming languages who want to learn Python. It covers most Python-related issues and should be sufficient for most people to get started with Python.

• docs.python.org/howto: Detailed information on subjects such as regular expressions, Internet programming, and Python style.

Blender scripting

Specific information on Blender scripting is readily available too.

• http://wiki.blender.org/index.php/Doc:Manual/Extensions/Python: Gives important information on how to install and use Python with Blender on different platforms and includes information on the built-in editor.

• http://www.blender.org/documentation/249PythonDoc/: The official documentation of Blender’s Python API. This is the page we refer to in this book when we mention “the API documentation”. Before you start scripting, read this at least twice from start to finish. It will give you an excellent overview of what is possible and by reading it completely, you will find it easier to find something when you need the information.

• wiki.blender.org/index.php/Extensions:Py/Scripts: A catalog of the many, many scripts available for Blender, both the bundled ones and the additional ones people have written. Before trying to invent something on your own, check to see if someone already invented it for you.

• www.opengl.org/sdk/docs/man/: The Blender Python API also gives access to many OpenGL functions to draw things directly on screen. The API documentation refers to these pages for detailed information. OpenGL is not a subject taken up lightly so you might want to check some tutorials first if you want to get fancy. http://www.opengl.org/code/ lists some entries that might give a start.

OVERVIEW

The book has no grammatical errors as far as I am concerned and explanation on matters are straight forward meaning one can understand  it with time or after research on the same somewhere else. And the fact that relevant links concerning different aspects of Blender have been provided.

The information on Blender 2.5 and Python was helpful.

GOOD READ!