'Quick Lava Tutorial'

Here are a few tips to quickly making a stream of flowing lava. I hope somebody out there can use it.

Start by making a box like this. You will need to make it large enough to contain all the lava for the entire animation.

Add a turbosmooth and some noise, for geometrical variation:

Create an FFD box (as a separate object, NOT as a modifier!) around part of the lava, like this, and bind the lava to the FFD with a space-warp bind

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Bend the lava into shape by moving the FFD box control points:

Go to the final frame in the timeline, turn on ANIMATE, and move the lava through the FFD box

Voila, you're done! Play back the animation, and the lava is flowing.

Here is an animation of the lava.
http://www.duck.dk/cgi/jussing_lava_animation_web.mov

Note that you will need to change the key-frame types to linear, if you want the lava's speed to be constant.

Also, as it appears in the picture above, as soon as the lava exits the FFD box, it will pop back to its unmodified position. You will need to take this into account.

source:----------------------------------------------
http://www.3dtotal.com/team/Tutorials_3/quick_lava_stream/quick_lava_tutorial01.php

Particle Systems ?.. What is that ?

Particles are essentially 2D images rendered in 3D space. They are primarily used for effects such as smoke, fire, water droplets, or leaves. A Particle System is made up of three separate Components: Particle Emitter, Particle Animator, and a Particle Renderer. You can use a Particle Emitter and Renderer together if you want static particles. The Particle Animator will move particles in different directions and change colors. You also have access to each individual particle in a particle system via scripting, so you can create your own unique behaviors that way if you choose.

Please view the Particle Scripting Reference here.

The remainder of this page's text is from the Particle Component Reference pages.

Particle Components

Particle Systems

Particle Systems in Unity are used to make clouds of smoke, steam, fire and other atmospheric effects. Particle Systems work by using one or two Textures & drawing them many times, creating a chaotic effect.

A Particle System included in the Standard Assets

A typical Particle System in Unity is an object that contains a Particle Emitter, a Particle Animator and a Particle Renderer. The Particle Emitter generates the particles, the Particle Animator moves them over time, and the Particle Renderer draws them on the screen.

If you want your particles to interact with the world, add a Particle Collider Component to the GameObject.

Ellipsoid Particle Emitter

The Ellipsoid Particle Emitter spawns particles inside a sphere. Use the Ellipsoid property below to scale & stretch the sphere.

The Ellipsoid Particle Emitter Inspector

Properties

Emit	If enabled, the emitter will emit particles.
Min Size	The minimum size each particle can be at the time when it is spawned.
Max Size	The maximum size each particle can be at the time when it is spawned.
Min Energy	The minimum lifetime of each particle, measured in seconds.
Max Energy	The maximum lifetime of each particle, measured in seconds.
Min Emission	The minimum number of particles that will be spawned every second.
Max Emission	The maximum number of particles that will be spawned every second.
World Velocity	The starting speed of particles in world space, along X, Y, and Z.
Local Velocity	The starting speed of particles along X, Y, and Z, measured in the object's orientation.
Rnd Velocity	A random speed along X, Y, and Z that is added to the velocity.
Emitter Velocity Scale	The amount of the emitter's speed that the particles inherit.
Tangent Velocity	The starting speed of particles along X, Y, and Z, across the Emitter's surface.
Simulate In World Space	If enabled, the particles don't move when the emitter moves. If false, when you move the emitter, the particles follow it around.
One Shot	If enabled, the particle numbers specified by min & max emission is spawned all at once. If disabled, the particles are generated in a long stream.
Ellipsoid	Scale of the sphere along X, Y, and Z that the particles are spawned inside.
MinEmitterRange	Determines an empty area in the center of the sphere - use this to make particles appear on the edge of the sphere.

Details

Ellipsoid Particle Emitters (EPEs) are the basic emitter, and are included when you choose to add a Particle System to your scene from Components->Particles->Particle System. You can define the boundaries for the particles to be spawned, and give the particles an initial velocity. From here, use the Particle Animator to manipulate how your particles will change over time to achieve interesting effects.

Particle Emitters work in conjunction with Particle Animators and Particle Renderers to create, manipulate, and display Particle Systems. All three Components must be present on an object before the particles will behave correctly. When particles are being emitted, all different velocities are added together to create the final velocity.

Spawning Properties

Spawning properties like Size, Energy, Emission, and Velocity will give your particle system distinct personality when trying to achieve different effects. Having a small Size could simulate fireflies or stars in the sky. A large Size could simulate dust clouds in a musky old building.

Energy and Emission will control how long your particles remain onscreen and how many particles can appear at any one time. For example, a rocket might have high Emission to simulate density of smoke, and high Energy to simulate the slow dispersion of smoke into the air.

Velocity will control how your particles move. You might want to change your Velocity in scripting to achieve interesting effects, or if you want to simulate a constant effect like wind, set your X and Z Velocity to make your particles blow away.

Simulate in World Space

If this is disabled, the position of each individual particle will always translate relative to the Position of the emitter. When the emitter moves, the particles will move along with it. If you have Simulate in World Space enabled, particles will not be affected by the translation of the emitter. For example, if you have a fireball that is spurting flames that rise, the flames will be spawned and float up in space as the fireball gets further away. If Simulate in World Space is disabled, those same flames will move across the screen along with the fireball.

Emitter Velocity Scale

This property will only apply if Simulate in World Space is enabled.

If this property is set to 1, the particles will inherit the exact translation of the emitter at the time they are spawned. If it is set to 2, the particles will inherit double the emitter's translation when they are spawned. 3 is triple the translation, etc.

One Shot

One Shot emitters will create all particles within the Emission property all at once, and cease to emit particles over time. Here are some examples of different particle system uses with One Shot Enabled or Disabled:

Enabled:

• Explosion
• Water splash
• Magic spell

Disabled:

• Gun barrel smoke
• Wind effect
• Waterfall

Min Emitter Range

The Min Emitter Range determines the depth within the ellipsoid that particles can be spawned. Setting it to 0 will allow particles to spawn anywhere from the center core of the ellipsoid to the outer-most range. Setting it to 1 will restrict spawn locations to the outer-most range of the ellipsoid.

Min Emitter Range of 0

Min Emitter Range of 1

Hints

• Be careful of using many large particles. This can seriously hinder performance on low-level machines. Always try to use the minimum number of particles to attain an effect.
• The Emit property works in conjunction with the AutoDestruct property of the Particle Animator. Through scripting, you can cease the emitter from emitting, and then AutoDestruct will automatically destroy the Particle System and the GameObject it is attached to.

Mesh Particle Emitter

The Mesh Particle Emitter emits particles around a mesh. Particles are spawned from the surface of the mesh, which can be necessary when you want to make your particles interact in a complex way with objects.

The Mesh Particle Emitter Inspector

Properties

Emit	If enabled, the emitter will emit particles.
Min Size	The minimum size each particle can be at the time when it is spawned.
Max Size	The maximum size each particle can be at the time when it is spawned.
Min Energy	The minimum lifetime of each particle, measured in seconds.
Max Energy	The maximum lifetime of each particle, measured in seconds.
Min Emission	The minimum number of particles that will be spawned every second.
Max Emission	The maximum number of particles that will be spawned every second.
World Velocity	The starting speed of particles in world space, along X, Y, and Z.
Local Velocity	The starting speed of particles along X, Y, and Z, measured in the object's orientation.
Rnd Velocity	A random speed along X, Y, and Z that is added to the velocity.
Emitter Velocity Scale	The amount of the emitter's speed that the particles inherit.
Tangent Velocity	The starting speed of particles along X, Y, and Z, across the Emitter's surface.
Simulate In World Space	If enabled, the particles don't move when the emitter moves. If false, when you move the emitter, the particles follow it around.
One Shot	If enabled, the particle numbers specified by min & max emission is spawned all at once. If disabled, the particles are generated in a long stream.
Interpolate Triangles	If enabled, particles are spawned all over the mesh's surface. If disabled, particles are only spawned from the mesh's vertrices.
Systematic	If enabled, particles are spawned in the order of the vertices defined in the mesh. Although you seldom have direct control over vertex order in meshes, most 3D modelling applications have a very systematic setup when using primitives. It is important that the mesh contains no faces in order for this to work.
Min Normal Velocity	Minimum amount that particles are thrown away from the mesh.
Max Normal Velocity	Maximum amount that particles are thrown away from the mesh.

Details

Mesh Particle Emitters (MPEs) are used when you want more precise control over the spawn position & directions than the simpler Ellipsoid Particle Emitter gives you. They can be used for making advanced effects.

MPEs work by emitting particles at the vertices of the attached mesh. Therefore, the areas of your mesh that are more dense with polygons will be more dense with particle emission.

Particle Emitters work in conjunction with Particle Animators and Particle Renderers to create, manipulate, and display Particle Systems. All three Components must be present on an object before the particles will behave correctly. When particles are being emitted, all different velocities are added together to create the final velocity.

Spawning Properties

Spawning properties like Size, Energy, Emission, and Velocity will give your particle system distinct personality when trying to achieve different effects. Having a small Size could simulate fireflies or stars in the sky. A large Size could simulate dust clouds in a musky old building.

Energy and Emission will control how long your particles remain onscreen and how many particles can appear at any one time. For example, a rocket might have high Emission to simulate density of smoke, and high Energy to simulate the slow dispersion of smoke into the air.

Velocity will control how your particles move. You might want to change your Velocity in scripting to achieve interesting effects, or if you want to simulate a constant effect like wind, set your X and Z Velocity to make your particles blow away.

Simulate in World Space

If this is disabled, the position of each individual particle will always translate relative to the Position of the emitter. When the emitter moves, the particles will move along with it. If you have Simulate in World Space enabled, particles will not be affected by the translation of the emitter. For example, if you have a fireball that is spurting flames that rise, the flames will be spawned and float up in space as the fireball gets further away. If Simulate in World Space is disabled, those same flames will move across the screen along with the fireball.

Emitter Velocity Scale

This property will only apply if Simulate in World Space is enabled.

If this property is set to 1, the particles will inherit the exact translation of the emitter at the time they are spawned. If it is set to 2, the particles will inherit double the emitter's translation when they are spawned. 3 is triple the translation, etc.

One Shot

One Shot emitters will create all particles within the Emission property all at once, and cease to emit particles over time. Here are some examples of different particle system uses with One Shot Enabled or Disabled:

Enabled:

• Explosion
• Water splash
• Magic spell

Disabled:

• Gun barrel smoke
• Wind effect
• Waterfall

Interpolate Triangles

Enabling your emitter to Interpolate Triangles will allow particles to be spawned between the mesh's vertices. This option is off by default, so particles will only be spawned at the vertices.

A sphere with Interpolate Triangles off (the default)

Enabling this option will spawn particles on and in-between vertices, essentially all over the mesh's surface (seen below).

A sphere with Interpolate Triangles on

It bears repeating that even with Interpolate Triangles enabled, particles will still be denser in areas of your mesh that are more dense with polygons.

Systematic

Enabling Systematic will cause your particles to be spawned in your mesh's vertex order. The vertex order is set by your 3D modeling application.

An MPE attached to a sphere with Systematic enabled

Normal Velocity

Normal Velocity controls the speed at which particles are emitted along the normal from where they are spawned.

For example, create a Mesh Particle System, use a cube mesh as the emitter, enable Interpolate Triangles, and set Normal Velocity Min and Max to 1. You will now see the particles emit from the faces of the cube in a straight line.

See Also

• How to make a Mesh Particle Emitter

Hints

• Be careful of using many large particles. This can seriously hinder performance on low-level machines. Always try to use the minimum number of particles to attain an effect.
• The Emit property works in conjunction with the AutoDestruct property of the Particle Animator. Through scripting, you can cease the emitter from emitting, and then AutoDestruct will automatically destroy the Particle System and the GameObject it is attached to.
• MPEs can also be used to make glow from a lot of lamps placed in a scene. Simply make a mesh with one vertex in the center of each lamp, and build an MPE from that with a halo material. Great for evil sci-fi worlds.

Particle Animator

Particle Animators move your particles over time, you use them to apply wind, drag & color cycling to your particle systems.

The Particle Animator Inspector

Properties

Does Animate Color	If enabled, particles cycle their color over their lifetime.
Color Animation	The 5 colors particles go through. All particles cycle over this - if some have a shorter life span than others, they will animate faster.
World Rotation Axis	An optional world-space axis the particles rotate around. Use this to make advanced spell effects or give caustic bubbles some life.
Local Rotation Axis	An optional local-space axis the particles rotate around. Use this to make advanced spell effects or give caustic bubbles some life.
Size Grow	Use this to make particles grow in size over their lifetime. As randomized forces will spread your particles out, it is often nice to make them grow in size so they don't fall apart. Use this to make smoke rise upwards, to simulate wind, etc.
Rnd Force	A random force added to particles every frame. Use this to make smoke become more alive.
Force	The force being applied every frame to the particles, measure relative to the world.
Damping	How much particles are slowed every frame. A value of 1 gives no damping, while less makes them slow down.
Autodestruct	If enabled, the GameObject attached to the Particle Animator will be destroyed when all particles disappear.

Details

Particle Animators allow your particle systems to be dynamic. They allow you to change the color of your particles, apply forces and rotation, and choose to destroy them when they are finished emitting. For more information about Particle Systems, reference Mesh Particle Emitters, Ellipsoid Particle Emitters, and Particle Renderers.

Animating Color

If you would like your particles to change colors or fade in/out, enable them to Animate Color and specify the colors for the cycle. Any particle system that animates color will cycle through the 5 colors you choose. The speed at which they cycle will be determined by the Emitter's Energy value.

If you want your particles to fade in rather than instantly appear, set your first or last color to have a low Alpha value.

An Animating Color Particle System

Rotation Axes

Setting values in either the Local or World Rotation Axes will cause all spawned particles to rotate around the indicated axis (with the Transform's position as the center). The greater the value is entered on one of these axes, the faster the rotation will be.

Setting values in the Local Axes will cause the rotating particles to adjust their rotation as the Transform's rotation changes, to match its local axes.

Setting values in the World Axes will cause the particles' rotation to be consistent, regardless of the Transform's rotation.

Forces & Damping

You use force to make particles accelerate in the direction specified by the force.

Damping can be used to decelerate or accelerate without changing their direction:

• A value of 1 means no Damping is applied, the particles will not slow down or accelerate.
• A value of 0 means particles will stop immediately.
• A value of 2 means particles will double their speed every second.

Destroying GameObjects attached to Particles

You can destroy the Particle System and any attached GameObject by enabling the AutoDestruct property. For example, if you have an oil drum, you can attach a Particle System that has Emit disabled and AutoDestruct enabled. On collision, you enable the Particle Emitter. The explosion will occur and after it is over, the Particle System and the oil drum will be destroyed and removed from the scene.

Note that automatic destruction takes effect only after some particles have been emitted. The precise rules for when the object is destroyed when AutoDestruct is on:

• If there have been some particles emitted already, but all of them are dead now, or
• If the emitter did have Emit on at some point, but now Emit is off.

Hints

• Use the Color Animation to make your particles fade in & out over their lifetime - otherwise, you will get nasty-looking pops.
• Use the Rotation Axes to make whirlpool-like swirly motions.

Particle Collider

The World Particle Collider is used to collide particles against other Colliders in the scene.

A Particle System colliding with a Mesh Collider

Properties

Bounce Factor	Particles can be accelerated or slowed down when they collide against other objects. This factor is similar to the Particle Animator's Damping property.
Collision Energy Loss	Amount of energy (in seconds) a particle should lose when colliding. If the energy goes below 0, the particle is killed.
Min Kill Velocity	If a particle's Velocity drops below Min Kill Velocity because of a collision, it will be eliminated.
Collides with	Which Layers the particle will collide against.
Send Collision Message	If enabled, every particle sends out a collision message that you can catch through scripting.

Details

To create a Particle System with Particle Collider:

1. Create a Particle System using GameObject->Create Other->Particle System
2. Add the Particle Collider using Component->Particles->World Particle Collider

Messaging

If Send Collision Message is enabled, any particles that are in a collision will send the message OnParticleCollision() to both the particle's GameObject and the GameObject the particle collided with.

Hints

• Send Collision Message can be used to simulate bullets and apply damage on impact.
• Particle Collision Detection is slow when used with a lot of particles. Use Particle Collision Detection wisely.
• Message sending introduces a large overhead and shouldn't be used for normal Particle Systems.

Particle Renderer

The Particle Renderer renders the Particle System on screen.

The Particle Renderer Inspector

Properties

Materials	Reference to a list of Materials that will be displayed in the position of each individual particle.
Camera Velocity Scale	The amount of stretching that is applied to the Particles based on Camera movement.
Stretch Particles	Determines how the particles are rendered.
Billboard	The particles are rendered as if facing the camera.
Stretched	The particles are facing the direction they are moving.
SortedBillboard	The particles are sorted by depth. Use this when using a blending material.
VerticalBillboard	All particles are aligned flat along the X/Z axes.
HorizontalBillboard	All particles are aligned flat along the X/Y axes.
Length Scale	If Stretch Particles is set to Stretched, this value determines how long the particles are in their direction of motion.
Velocity Scale	If Stretch Particles is set to Stretched, this value determines the rate at which particles will be stretched, based on their movement speed.
UV Animation	If either of these are set, the UV coordinates of the particles will be generated for use with a tile animated texture. See the section on Animated Textures below.
X Tile	Number of frames located across the X axis.
Y Tile	Number of frames located across the Y axis.
Cycles	How many times to loop the animation sequence.

Details

Particle Renderers are required for any Particle Systems to be displayed on the screen.

A Particle Renderer makes the Gunship's engine exhaust appear on the screen

Choosing a Material

When setting up a Particle Renderer it is very important to use an appropriate material and shader. Most of the time you want to use a Material with one of the built-in Particle Shaders. There are some premade materials in the Standard Assets->Particles->Sources folder.

Creating a new material is easy:

1. Select Assets->Create Other->Material from the menu bar.
2. The Material has a shader popup, choose one of the shaders in the Particles group. Eg. Particles->Multiply.
3. Now assign a Texture. The different shaders use the alpha channel of the textures slightly differently, but most of the time a value of black will make it invisible and white in the alpha channel will display it on screen.

Distorting particles

By default particles are rendered billboarded. That is simple square sprites. This is good for smoke and explosions and most other particle effects.

Particles can be made to either stretch with the velocity. This is useful for sparks, lightning or laser beams. Length Scale and Velocity Scale affects how long the stretched particle will be.

Sorted Billboard can be used to make all particles sort by depth. Sometimes this is necessary, mostly when using Alpha Blended particle shaders. This can be expensive and should only be used if it really makes a quality difference when rendering.

Animated textures

Particle Systems can be rendered with an animated tile texture. To use this feature, make the texture out of a grid of images. As the particles go through their life cycle, they will cycle through the images. This is good for adding more life to your particles, or making small rotating debris pieces.

source:----------------------------------------------
http://unity3d.com/support/documentation/Manual/Particle%20Systems.html

Super Cool Watercolor Effect in 10 steps in Photoshop

Last year I wrote a Photoshop tutorial for PSDTUTS showing how to create a very nice design using watercolor brushes. It was inspired by the work of guys such as Bruno Fujii, Margot Mace, Raphaël of My Dead Pony and Stina Person. This time I will create another effect but it will be using Masks and Watercolor brushesl; it's inspired by another great digital artist, the master Scott Hansen the mind behind ISO 50 and also some images from the Daily Inspiration.

So in this tutorial we will use Photoshop, some brushes from Brusheezy and some stock photos.

Step 1

Open Photoshop and create a new document, I'm using 1920x1200 pixels.

Step 2

Add a new layer, fill it with white then make sure you have black and white for the foreground and background colors. Then go to Filter>Texture>Texturizer. Use Canvas for the Texture, 75% for the Scaling, 3 for the Relief and for the Light choose Top Right.

Step 3

Let's add a nice texture. You can use the image of your choice it could be parchment paper for example. I'm using a image from Shutterstock that you can buy it at: http://www.shutterstock.com/pic-20845342-old-yellow-paper-background-with-scratches.html

Place the image in the document on top of the other layers. After that, change the Opacity to 75%.

Step 4

Now let's place an image in our document. I'm using a photo of a guy walking in the field from Shutterstock, you can get it here. The image has to go beneath the texture layer. After that go to Layer>Group Layer. The layer of the image will be inside a folder in the Layer Palette. Select the folder and go to Layer>Layer Mask>Hide all.

Step 5

The image is hiding because of the mask. So now, let's use some Watercolor Brushes. The ones I use are from Brusheezy and you can download them here http://www.brusheezy.com/brushes?search=watercolor.

So select one of the watercolor brushes and them white for the color and paint on the layer mask of the group. You will notice that the image will start showing.

Step 6

Pick another Brush and paint again.

Step 7

Keep painting untill you can see the image without losing the brush splatters.

Step 8

Now add another layer, this time beneath the Folder that the image is in. Then again using the watercolor brushes paint over the layer using colors like: pink, blue and yellow. Use the image below for reference.

Step 9

Let's just adjust the color of the image. Select the image and go to Image>Adjustment>Photo Filter. Select Warning Filter (85) and 55% for the Density. Also select the Preserve Luminosity option

Step 10

Select the image and go to Filter>Artistic>Dry Brush. Use 0 for the Brush Size, 9 for the Brush Detail and 1 for the Texture.

Conclusion

Just place your logo and that it you will have a really cool effect and super simple to achieve. That can be used for website headers to create a simply awesome design, and, of course to create posters. Also you can reduce the opacity of the paper texture. I reduced to 50%, that way we can drive the viewer's attention to the watercolor effect.

Version 2

You can try different images as well like the one below.

Download the Photoshop File

Click here to download the Photoshop file used for this tutorial


source:----------------------------------------------
http://abduzeedo.com/super-cool-watercolor-effect-10-steps-photoshop

Transformers: Revenge of the Fallen (2009)

Nothing too special from the film transformers sekuel second, though supported by the visual effect is very powerful but not fully satisfactory in the case of continuous flow of the story too slump impressed so ragged, but that little payy off no time with the robot action This lego robot-dance over canvas basin modeling .. or may be times striptease dancers .. hehe

Michael Bay, director of the opening 'Transformers: Revenge of the Fallen' scene with a group of Transformers robots to build a giant machine on the earth 17 thousand BC. The scene is a guide to ease you to follow the film plot.

Proceeded to the scene of the present, when the Autobots and the United States to join the army formed NEST. A secret organization tasked to pursue the remaining Decepticon forces that lurk.

One time, NEST to find some Decepticon in Shanghai, China and the sideways Demolishor which are large. Without the constraints encountered, Optimus Cs was successful in destroying two Decepticon. But before killed, Demolishor had said something to the Optimus. "The Fallen will rise," said Demolishor.

In other places, Sam Witwicky (Shia LaBeouf) is preparing to move to the residence to continue his study. However, when put in order, Sam found a small snippet of the AllSpark, a cube-shaped object appears in the first movie 'Transformers,' in his jacket.

Accidentally, Sam touch. The sudden, things that directly re mind with Sam codes mysterious ancient Cybertronian. Well, start from there-scenes exciting and tense scenes flow downpours.

'Transformers: Revenge of the Fallen' show more robots. There are 30 more robots in action in the film that also been by Steven Spielberg. One of the robots that the presence, Devastator or the more commonly known as The Constructicons.

It is not surprising if the Shia LaBeouf and Megan Fox injuries often use to film this time. 'Transformers: Revenge of the Fallen' explosion-laden with the large-scale explosion.

Visual effects the film does not need to doubt its quality and should get two thumbs up. Autobot and Decepticon look very detail, his move perfect without any defects.

In addition to visual effects, and so forth, actor-actress this film should get the shaft. Moreover, the section's Megan Fox as a confection capable so additional attraction for 'Transformers: Revenge of the Fallen'.

Next forward for the third Transformers.

Tutorial: Its all in the Eyes

Eyes

Creating a character is one thing but creating a character in 3d that has depth is another. In life, the eye is a window to the soul. Eyes show inner thought because they have depth to them. At some level we read the eye ball without even knowing how or why certain looks evoke an emotion. We can compare this to body language. We can tell when a human is feeling sad by looking at their "pose" and the way they move slowly and kind of careless. But we can further more tell that they are sad by the way their eyes look and move. The eyes of this sad subject may be more wet because of tears and their movement may be slowed, maybe even timid. Also the eyes will kind of stare at something symbolizing a more focused inner thought. Believe it or not this is all common sense, your mind knows all of these things. However you may have never thought about it consciously.

As 3d artists we have the ability to create photo real images. In that case we must pay great attention to detail when it comes to relating the thought, or emotion that we're trying to convey to our audience. One way to do this is to pay great attention to the eye ball. The most simplest form is a texture map on a sphere. In some small cases this is enough such as background extras, or characters that will be shaded in a special way etc. (click here for an example of a sphere and texture map eye created by me) However I tend to subscribe to the Pixar's belief that the eye needs a lot of attention in order to convey life. To me, a lifeless eye can ruin an image. An artist can model a photo realistic head in 3d but it will look lifeless if the eyes lacks depth.

So how do we create depth? Well like i sad, a sphere with texture map works for some scenes especially if its a more cartoony or stylized character, and its even better if there's a bump map as well. However looking at Pixar's "A Bugs Life, we see a lot of depth in the eyeball. From this we can assume that they didn't use a simple sphere with a texture map. In fact this suggests they've modeled the eye more physically correct. Now I'm no surgeon so I'm not going to chart out the entire structure of an eye. I'm an artist so I'll fake it. That's what we do. One thing to remember is that if it looks good... its good enough.

Before we look at the eye. When I set out to figure out how to make a better eye for my characters i thought about dolls and the way their eyes were shaped and how they looked. You may find that this eye reminds you of older style dolls.

Lets look at the eye

Here's the eye. This eye is more of a "Pixar'ish" kind of eye in that its clean looking. Additional texture maps can make this eye more photo real, such as a pinkish map with some small vein like lines. I like the Pixar look so that's the inspiration for this eye and its shaders.

How real this eye looks depends on 3 factors: the actual geometry, shaders, and lighting. First we'll examine the geometry...

Geometry

The eye is modeled in 4 parts. They are:

• The actual circular structure of the eye white

• Pupil

• Cornea

• Iris

Each of these 4 parts are modeled individually. As you can see I've modeled the eye ball more physically correct in that the iris (the color of the eye) bends inward. This is very important to properly simulate the highlight and diffuse illumination that the iris has in real life. This angle allows the iris to literally catch light.

The Pupil is a simple flat black 2d circle that sits in the iris.

The Cornea is a key component to the eye. It allows us to catch sharp highlights and it gives the eye depth. Actually the combination of the cornea, iris and pupil are what give the appearance of depth but without the cornea this eye would look flat. The cornea is transparent and has a light reflection map. Its main purpose is to catch a sharp highlight

So far our example as been a polygon object. The same thing can be accomplished just fine in b-spline patch surfaces and nurbs. Lets look out a regular b-spline patch version of the eye made in 3dsmax (not a nurbs version)

As you can see the same thing is easily accomplished. Its just a different surface type. I prefer this surface type because it is very resolution independent. The polygon version is a meshsmooth object so i can acheive higher detail levels with the polygon one. The patch one allows me to tesselate down to a very small amount of polys, thus increasing viewport speed when animating interactivly.

Above you can see that i've turned down the patch surface tesselation parameters to 5. this allows realtime interactivity while retaining the ability the eyeballs perfectly smooth with a higher tesselation value. So if i was doing film res stuff... i could easily turn up the step setting so that my eyes dont have any poly facets in them.

The Good and Bad of patch eye ball surfaces.

GOOD:

• Resolution independent

• Fast interactivity

BAD:

• Doesnt work well with FFD's unless you have a lot of patch crossections. Mesh objects have no problem with FFD lattices

• Max has mapping issues with patches in r3 that prevent propper mapping of patches. The only way to get around this is to meshselect above the patch modifier and then map it as a polygon. This works fine as a work around but its not a desired work flow.

Now that we've examined the geometry. We must look further into what makes the eye more real such as lighting. The key to lighting the eye properly is partially in the structure but shaders are just as important.

The Shaders

Shaders and lighting go hand in hand, so in order for the eye to light properly we need to have proper shaders.

Each part of the eye contains a separate shader. There are 4 shaders in all.

• The Eye White shader

  

  The eye white shader simulates a fresnel like reflection where the reflection is more visible around the sides of the object and is less visible head on (although it doesn't look like it, there's is). It has a very high specularity value in order to create a sharp specular reflection.

• Pupil shader

  

  The pupil shader is very simple. Its a flat black color. There is no specularity or shininess settings. It doesn't have an ambient value either. This way it will be black when

  responding to light.

  
  

• Iris shader

  

  The iris shader has a texture map for color. The specular color is a map as well so it lights in a realistic manner. The specular settings are set in a way that you get a wide highlight but not a sharp one.

  
  

• Cornea shader

  

  The cornea shader is almost completely transparent. It has the same specular and shininess settings that the eye white shader has. It also has the same frensel reflection of the eye white shader. This is because they should appear to be all one structure and the highlights and reflections need to behave the same on both surfaces.

Other things to consider

This is very important. If you are using a shadow maps you need to tell the cornea object to not cast a shadow and to not receive them. Its transparent anyway so its ok that it doesn't cast a shadow. If you don't do this the cornea will black out the iris and you wont see the inner eye at all. If you are using ray tracing i suppose you don't have to worry.

Lighting the Eye

Modeling the eye is only a part of creating the illusion of depth. Lighting is the final touch. One must always have at least 1 specular highlight in the eyes. You can usually do this in most rendering software by defining a light source that only effects the eyeballs and further more this light source should only cast specular light. In other words this light will only effect the specularity of the eyeballs. In 3D-Studio Max you can easily do this by creating a light source and toggling the diffuse check box off, in the light source parameters. And don't forget to do "INCLUDE the eyeball objects only" in the light sources exclude/include parameter box

Animating the Eyeballs

Animating the eye is fairly simple. If your in 3D-Studio Max i suggest using the tape measure helper to animate the eye. A very good friend of mine and animation partner, Boris Ustaev came up with this. Its actually a lot better than using the Look at controller in Max. If you're a Maya user, just go ahead and aim constraint the eyes to a null. I suggest constraining each eyeball to its own null, and then constrain those 2 nulls to one. That way you have the ability to animate each eye separately if you need to.

If you'd like to dilate the pupils you can setup a linked xform in Max. This linked xform would be assigned to the vertecies around the inner edge of the iris. You will need to assign the vertecies around the outer part of the pupil as well to a linked xform. And then create a dummy in the middle of the pupil, and use that dummy to control both linked xform modifiers.

source:----------------------------------------------
http://www.3dluvr.com/rogueldr/tutorials/eye/eyes.html