Subscription based models

A few months ago, Digital Tutors introduced their subscription based model. Instead of buying individual tutorials, you pay a fee to get access to all their material.

Not long ago, Gnomon Workshop followed suit. They have three tiers, Visual Effects only, Design only , or all tutorials. Pay a yearly fee and get access to all Visual Effects-tutorials, all Design-tutorials or all tutorials whatsoever.

The advantage with this that I can see is that you don't have to choose. As long as you are a subscriber, you have access to all tutorials and can take a look at them as the need arises.

The disadvantage is just that, it's only as long as you are a subscriber. Stop your subscription, and you lose all the tutorials again. Basically, you are paying for something that you can't keep.

(Of course, nothing is stopping you from taking notes etc, but sometimes it's just not the same thing).

One difference I can see between Digital Tutors and Gnomon is that you can get montly subscriptions for DT, while Gnomon only let's you subscribe on a yearly basis. This makes the step into DT a bit smoother, you can try it out for a month before commiting several 100 USD to the service for a yearly subscription.

What's happening with Maya?

Today, on my workplace, I finally got to install Maya2010 and see what new things it contained.

The answer: Basically nothing! All the changes are external from the actual software (Complete-version dead, Toxic and Matchmover included etc), but within Maya, almost nothing has changed.

So, what is happening? Is maya going the way of the Dodo?

I don't think so. I do think 2010 is a dissapointment, but I also think there is a reason for it. From what I've gathered on forums like CGTalk etc, it seems that a major overhaul of Maya is underway. For instance, the GUI-handler will be replaced by something that will be a bit faster, a lot more cross-plattform-able.

My own guess is that the Maya-developers are busy working on the new version, rather than adding things to the "old" platform. So, let's keep our fingers crossed for a nice and impressive release of Maya 2011.

Just some pictures.. and a secret!!!

Today I went out to a nearby path that runs along a river (just a few minutes drive from where I live) and took some pictures.
The equipment is my Nikon D90 with the stock objective that comes with it (which I know isn't the best there is)

However, I'm quite pleased with how the photos turned out, and I owe it all to one secret:

I was there at the right time!

When it comes to landscape photography like this, the time of day is crucial. The fact that I left my warm and cosy bed at 7.20 on a saturday resulted in me getting a fair amount of decent pictures with nice light and greath atmosphere (including a couple of pictures of our new Subaru Legacy as well).

When I was at the place, it was just a matter of taking as many pictures as possible.
Another small tip I can give is to use a tele-objective with as much zoom as possible. This enhances the influence of any fog or mist in the air and gives more depth to the images.

Fusion 6 is on it's way

One of my favorite packages is Fusion from Eyeon. About two months ago I was at an early demo of the upcoming version, 6.0 and it looked impressive (well, Fusion looks impressive as it is, so that was no surprise there). However, at that time the release was quite far away. Fortunately, it isn't anymore. It seems like they have an open release candidate for their current subscribers.

For more on the new version, read on this link on Fusion 6.0

Blender 2.5 - a preview

The next major version of Blender, 2.5, is slowly maturing. All around the net, previews are leaking out. This video is one preview that shows a little bit about the interface.

Blender 2.5, - Got flexible? from Pablo Vazquez on Vimeo.

You can read more about blender on blender.org

Free image editors

Adobe Photoshop is a great tool, but it's also an expensive one. Six Revisions have put together a summary of 10 good open-source/free Image Editing tools to try out if Photoshop is out of your reach economically.

10 Excellent Open Source and Free Alternatives to Photoshop

Photo tips

This post in the blog Prophotolife contains a number of interesting links with resources for digital photography.

atn 36: links from creativity to photo instruction

Interesting thread on matte painting

This thread shows an interesting workflow when it comes to matte painting. It's a nice read if you are interested in finding new workflows/ getting new ideas for painting sceneries in Photoshop (for instance).

Animating a piston in Maya

Making a piston move correctly can be tricky, but here is a way to do it. I'm using expressions to solve it, because this makes it a bit easier and manageable.

First of all, consider this picture:
The distance between the center of the wheel is the sum of x1 and x2. Finding x1 is simple trigonometry (x1 = cos(rotation of the wheel)*L1).

Finding x2 is a bit trickier. Not much though.

Y, L2 and X2 also forms a triangle. We can set L2 to whatever length we want it to. Y varies with the rotation, and can be found with sin(rotation of the wheel)*L1.

So, we know have L2 and Y, and using Pythagoras theorem, we can calculate x2.

The code can look something like this:

float $l2 = 10; // Decide on L2
float $y = LOC_Radius.translateY*sind(LOC_Center.rotateX+90); //Calculate Y
float $x1 = LOC_Radius.translateY*cosd(LOC_Center.rotateX-90); //Calculate x1

float $x2 = sqrt($l2*$l2-$y*$y); //Calculate x2 from y and L2
LOC_Piston.translateZ = $x1+$x2; //Add x1 and x2 together to get the total translation.

LOC_Radius - where the first cylinder connects to the wheel
LOC_Center - Center of the wheel
LOC_Piston - the "pushing point" of the piston

After that, I just added some geometry to the locators so that it looks like a wheel and a piston. Mostly done with some parenting, point constraings and one aim constraint.

The result can be seen here:

Command line rendering and render queues in Maya

One little nifty trick one can do is to use the command line renderer that ships with maya. Or rather: When you start the Batch render -process from within maya, you are actually starting a separate process. Thing is, you can start this process from outside of maya, using just the command prompt. There are some advantages to this, two of these are
- Not having to spend system resources on Maya itself, the renders are slightly faster
- With a simple trick, you can put multiple scenes on queue.

The basics are simple, just open a command prompt from windows (or open the Maya Terminal in OSX). type Render myscene.mb.

Now, there are many flags you can set when using this command, but if everything is set in maya, that is all there is to it. Some other useful flags follow here:

-x int and -y int : The resolution of the Render
-s int and -e int: The starting frame and the last frame of the render
-rd : output directory
-im : output image file name

Render Queue

In windows, you have something called batch-files. These are text files that can contain several command prompt commands. For instance, you can create a file called myRenders.bat. In it you have two lines
Render scene1.mb
Render scene2.mb

When you run the batch-file (double click it or type myRenders.bat in the command prompt, the two commands will run after each other. In this case, you will render out first scene1 and then scene2.
This is useful if you have multiple scenes you want to render overnight. Just type a number of Render-commands in a batch file and you are ready to go.

With the use of flags, you can make multiple renders of the same scene as well. For instance, it would be easy to make a batch-file that did both the entire scenes, and also rendered out a particular frame from each scene in higher resolution (if you would want something like that.)

New book on Renderman

Two days ago I recieved a book I ordered. It's called The Renderman Shading Language Guide and is a thorough introduction to shader programming using the Renderman Shading Language.

So far it seems very good, although it focuses perhaps a bit to much on peripheral things like how to put up a good development environment rather than the actual programming. With that said, however, it seems like it goes into a great depth on shader programming. I will return with a more exhaustive review when I have read it through.

The official site of the book

3Delight - A high-end production Renderman renderer

I have been interested and fascinated by the Renderman renderer for quite some time now. It has, however, been slightly out of my reach due to it's costs. After looking at some of the open-source solutions out there I finally found the 3Delight engine. It's a profesional Renderman compliant engine that is used in high-end productions. It also integrates with Maya and XSI.

The cool thing is that they let you use the first license for free, including for commercial use. I have recently downloaded it and done some simple tests. I will return with more info and tips when I get more experience with it.

If you want to try it out for yourselves, the link is www.3delight.com

Combining two bump maps in Maya

Sometimes you want to combine two bump maps in Maya. How to do this isn't entierly clear, however. What you need to do is the following:

Let's say we have got two textures, textureA and textureB. We want to use them both as a bump map in maya.

• Connect the two textures to a bump2d-node each
• Connect one of the bump2d-nodes to the other.
• bump2d1.outNormal -> bump2d2.normalCamera
• Done!

The outNormal and normalCamera-attributes can be Hidden, and if you don't see them, check Left Display->Show Hidden and Right Display->ShowHidden in the connection editor.

Interesting read

Pixar has published a lot of papers on their different techniques on they used in their movies. They can be a bit technical, but interesting nonetheless.

http://graphics.pixar.com/

File Formats

.. is not something to be taken easy. I did a little study today, and found out, among other things, the following.

• Although Mental Ray supports the z-channel in OpenEXR, Mental Ray for Maya doesn't.
• RLE is an 8-bit format, but makes for the smoothest workflow when you need a z-channel from Maya to Adobe After Effects.
• iff can be used as a 16-bit format, but isn't widely supported
• Maya has a very short range in it's z-channel (from 0 to 1 at the most)

More points to be added as they show up..

More alien abstracti-isms

Another work of abstract Maya-art. My aim is to rediscover the joy and experimentation of 3d-work.

Experiment with abstract forms

This week I did some experimenting with abstract forms. I like the combination of organic irregular shapes and the contrasting regular sphere.

Workflow and tips on keeping the scene clean

This thread has some good advice about how to work with clean and organized scenes. Basically, it boils down to dividing your shot into multiple scenes, and then combining the rendered passes in compositing (among other things).

L-Systems, part II

In the last post, we looked at L-Systems and the basic principles of an L-System. This time we will take a quick look at how to use that in computer graphics.

An L-System can based on a string of characters, as seen in the previous post. Now, consider the following statement:

Each letter in this string represents an action.

Lets say that the system consists of three letters, D,R and L. Each of these letters represent an action.

D: Draw a line 1 unit long
R: Turn 90 degrees right. Do nothing else
L: Turn 90 degrees left. Do nothing else

So, the combination DRD would mean "Draw a line, turn right, and then draw another line in the new direction."

DRDRDRD would mean Draw a line, turn right, draw a line, turn right, draw a line, turn right and draw a final line. This would result in a cube.

Now, let's say we use rules to transform a string of these commands.

Example:

Starting string: DRD

Rules: D = D
R = DRDLDRD
L = DLDRDLD

As a small excerscise, draw the shapes DRD and it's "child" DDRDLDRDD.

As you see, small corners are added to each corner. For each generation, more corners are getting "cut out".

This is a simple start on how to use L-Systems for drawing. There are more advanced examples, and we will get back to those in a later post.

Powered by ScribeFire.

L-Systems pt I

L-Systems are commonly used to create complex patterns and constructs.

This and following posts are my attempt to understand these L-Systems more.

First of all, what is an L-System?

An L-system consists of two parts (roughly speaking). A chain (or a text string) and rules.

The chain can consist of any pre-defined components. To demonstrate I will use a chain of letters. The string AABA could be such a chain.

The rules describe how this chain should change. For instance

A = A
B = AB

You let the chain grow or change by running it through the rules, one component at a time. Let's consider the example above:

Chain: AABA
Rules: A=A
B=AB

First run:
First letter: A, becomes an A
Second letter: A, becomes an A
Third letter: B, becomes AB
Fourth letter: A, becomes A

The result is A+A+AB+A = AAABA

Second run:
First letter: A, becomes an A
Second letter: A, becomes an A
Third letter: A, becomes an A
Fourth letter: B, becomes AB
Fifthletter: A, becomes A

The result is A+A+A+AB+A = AAAABA

In this example, the chain was put through the same set of rules twice. In theory an L-System could be run any number of times, applying the rules over and over again.

Which each iteration, the string evolves and changes according to the rules.

There are a couple of basic patterns that is worth mentioning.

The first one is where you add complexity in the middle of the string.
Example:
Chain: ABA
Rules A = AB, B = A

First run: AB+A+AB = ABAAB
Second run: AB+A+AB+AB+A = ABAABABA
Third run: AB+A+AB+AB+A+AB+A+AB = ABAABABAABAAB

and so on. As can be seen, the string grows longer, and more complex all the time.

Consider instead this string, and in this case, I'll use three letters. The basic principle is the same.

Chain ABX
Rules, A=A, B=B, X=ABX

First run A+B+ABX = ABABX
Second run: A+B+A+B+ABX = ABABABX
Third run: A+B+A+B+A+B+ABX = ABABABABX

In this example, the inner structure isn't changed, instead a tail is added to the end for each run. This is accomplished with a tail component that adds a string+the tail component for each run.

These L-systems can use an indefinite number of rules and components. I could have an L-System with all the letters of the alphabet and a multitude of rules, creating something very complex.

So, what can we do with this then?