Velocity....

While busy at work, I noticed that my understanding of Velocity when compared to other people, wasn't the same.  So, I'm going to do a little simple tutorial on Velocity soon, just to see how the math/physic's look in ICE.

I will be updating this post over the weekend or so.

:D

SO what is Velocity?

Velocity: the speed and direction of an object, or its rate of change in position. This is a vector.

http://download.autodesk.com/global/docs/softimage2013/en_us/userguide/index.html

SO according to ICE, Velocity has to do with . . . "position", "direction" , and "change in position which = speed/rate"

And the formula for Velocity looks like this :

or.....

which basically means Velocity = Displacement( "position", "direction") divided by change in time("change in position which = speed/rate")

a.k.a change in position over a change in time


Finding the rate or speed:

You might be thinking how can I find out what the rate or speed of said strand/particle/point is? Speed is a Scalar value, this means it has direction over time but not a position as with velocity/vectors.

Here is the formula for speed/rate:

Some cool Tutorials on Velocity\speed and acceleration can be found here:
http://www.khanacademy.org/science/physics


too be continued..... :D

Making a turbulence fall off along a strand

Got a Comment from Chris on fall offs for turbulence, Sorry for the late replay been hectic at work(and diablo :D)

But anyway, straight to it then.

Bring into your Ice Tree the TF_Frizz_Strands_by_Turbulence node, it looks like this:

*click to make bigger*

Now to add the fall off you will have to go inside the compound and add the following nodes:

*click to make bigger*

Basically what you are doing is multiplying the turbulence with the fcurve, where its value is zero there will be no turbulence, where the value is 1(1.5) there will be turbulence.

*click to make bigger*

So before the fall off it looked like-----

*click to make bigger*

And after ------

*click to make bigger*

Hope that helps with your project Chris :D

Cool Post from the Simon

Alo blog,

just a link to my friend Simons blog, quite a cool post he put up

http://vinyldevelopment.wordpress.com/2012/06/12/debugging-your-rigs-scene/


:D

DIABLO 3

Alo blog,

Got Diablo 3 sooooooo been playing that, and probably will for sometime. Will get back to exploring ice as soon as I get tired of killing Zombies and stuff :D

over and out

Fur, Feathers, and Scales

Fur, Feathers, and scales

The last year or so I have been making lots of the above mentioned. And now after all my suffering I would love to build these systems for myself, so that if I EVER have to use them again that I would be ready and prepared ..... kinda.

I'm going to use my blog as a way to keep track of everything I learn and everything I try sooooo Hopefully it will help me not get distracted too much.

To start:

I have been using a combination of melena, normal soft strands, and 3dquacks verlet integration to make Khumba's fur. I found this to be an "ok" way to make fur, but it is heavy and "jittery". So I'm hoping to improve on this.

The feathers are melena but with a huge twist, and the scales is a whole new system i made on the fly so these two need the most work :D

Yeah for ICE \:D/

Vector Fields and simple Math

Alo blog :D

Last night while waiting for some feather stuff for work to render, I played with a Vector visualizer I got from a cool guy named  Fabricio Chamon. Well at fist I was just messing around with normal turbulence and then I fed some curves through it, but I got bored :D so I got a thinking what simple math would look like in there. What a lot of fun I had doing that..... this weekend I want to put some images up for you all to see. Best way ever to make new and interesting forces.

O here is an example of the math

y = x^2 * z^2

Back to Vector Fields

Just an update on this subject. :D

I found Exocortex/Slipstream yesterday and boy how cool is their use of Vector Fields, I'm so green with Envy right now. Will be learning as much as I can from their system, obviously.

http://www.exocortex.com/plugins/slipstreamvx

On my wish list of things I really want to be able to make. XD

Fur Nodes using Melena Base for Khumba

Alo again :D

Here are the Compounds I made and used to create the fur,feathers and Scales for Khumba the Movie.
P.S. It needs melena as a base. Hopefully when I'm done with the whole system it wont need that any more as I found that the curve sets it creates are super heavy. Any way here is the link......

https://docs.google.com/file/d/0B8MfxqvWZh32dXd5ZnV5ZFpEWnM/edit

Just a note, I'm still a noob at Ice in general sooooo, just saying :D

Enjoy

Vector Flow

Alo blog,

In my making of a Pangolin character at work, I was told about these cool Tutorials about vector flow with a curve.

http://vimeo.com/36709750

And it got me wondering about vector fields in general, and how they can be modified.  Sooooo.... I went to Wiki to find out what a vector field is, really.

http://en.wikipedia.org/wiki/Vector_field

And that looks pretty awesome, but how do I bring this into ICE for me to use?

Tutorial on Ice Fundamentals.

ICE Fundamentals.

ICE — the Interactive Creative Environment is a visual programming system in Autodesk^® Softimage^®

ICE Attributes 

Attributes can be inherent, predefined, or custom.

Inherent 

Inherent attributes represent data that is always available in the scene.

Predefined

Predefined attributes are recognized and used by certain basic nodes. However, unlike inherent attributes they are dynamic, meaning that they do not exist until they are set.

Custom

Your ICE tree needs to use a compound that explicitly gets this attribute and uses it in some way.

ICE Attributes

ICE Simulation

Simulated means that the result of the current frame depends on the result of the previous frame rather than on the results of the construction regions that are below it. This is what differentiates a simulation from other types of modifications to an object. For example, if you use a Push deformation on a sphere, at each frame the Push operator gets the undeformed sphere and applies the push. If you move one frame forward, the Push gets the undeformed geometry again and applies the same push.

The only way to modify the push deformation over time is to animate its parameters. However, if the Push operator is in the Simulation region, at each frame it takes the results of the sphere's pushed points from the previous frame and pushes them out more. As you play the simulated push, you see the sphere gradually inflating, without any animation being defined. The only way to return to the undeformed sphere is to go back to the first frame.

When a simulation is active, the regions below the Simulation region are not re-evaluated. This means that if you have any operators in the Animation region, those operators are not evaluated again after the simulation is active. If you want to return to using the animation operators instead of the simulation, simply select and delete the Simulation marker from the stack so that there's no Simulation region.

Simulate Particles Node

The Simulate Particles node is the "standard" particles node that updates the position and velocity of each particle at each frame by doing the following. It:

• Calculates the point accelerations based on mass and force.
• Updates the point velocities based on acceleration.
• Updates the point positions based on velocity.

Sets the simulated frame fraction to 1. The SimulatedFrameFraction attribute defines the fraction of a frame that has already been simulated for a point. Setting this value to 1 prevents points from being resimulated by other Simulate nodes in the same tree (such as the Simulate Rigid Bodies node) or in other trees on the same object.

The Emitter compounds that use this node automatically set the SimulatedFrameFraction to (1 – Age/SimulationStep) so that on its first frame of existence, a particle moves only for a distance proportional to its age. As a result, it appears as if particles have been emitted continuously throughout the frame instead of all at once.

ICE Forces

•  Velocity: the speed and direction of an object, or its rate of change in position. This is a vector.
•  Speed: the amplitude of the velocity (the length of the velocity vector) but without the direction that velocity has. This is the ratio of the distance an object moves versus the time it takes.
•  Acceleration: the rate of change of velocity.
  For more information on velocity, speed, and acceleration.
•  Force: a push on an object that infers a change in velocity. It is also a vector that indicates the direction of the push. Its length determines the strength of the push.
  Force is a vector that gets applied to an object to change its velocity, and the object's mass is taken into consideration (Force = Mass * Acceleration). The Force is calculated by the change in velocity multiplied by the mass.
  When the Simulate Particles node applies force to a particle's position, it takes into account the particle mass.
•  Mass: the quantity of matter of an object. The mass determines how quickly objects react to the forces applied to them and how they react in a collision with an obstacle. Objects with a higher mass tend to keep their velocity when exerting forces on them. Therefore, to make a change in an object's motion, you need to apply stronger forces to an object with more mass than to one with little mass.
  
  
•  Gravity: the attraction between all objects that have mass. Earth's gravity is a downward acceleration exerted on objects.
  
  
•  Drag: a force applied by a fluid on a solid object in the opposite direction to its velocity. The force depends on the velocity of the object and its size, and on the density of the fluid.

ICE Simulation Regions and Nodes
ICE Forces


Here is the Ice Tree we used as an example:   

*click to make bigger*

And that's it :D

Thanks