Product Rendering: Futuristic PDA?

I started a new course in Product Visualization and Rendering with Maya/Mental Ray. They stressed how we need to keep up with industrial design, design mags...ie have to keep checking out what is cool and in style so that our reel/demo reflects what is in demand. Our first assignment was to design a PDA of the future, model and render with Maya, and composite it with a photo we shot. I came up with one that is compact, has a flexible,clear, and retractable OLED screen, and is super thin. That's what i would want anyway. I took a shot of my own hand and then composited it. I tried to make it into a mock ad, so I guess I went a bit far but was having fun so what the heck..

Week 9: Dynamics-Texture emission from an object

Just finished working on probably the toughest particle challenge yet...the exercise here was to camera project a background plate with coke can sitting on a hydrant onto a 3d version of the can. Then, the can will 'emit' particles in the same color as its label and be blow away by the wind revealing a 'glass' can underneath. whew! Took a bit longer to do then to explain, but learned a lot about hardware rendering with this one.

Enjoy!

Week 9: Dynamics_Particle Emitters

We started the last and final week with a bang: dynamics. More specifically we focused on particles and forces and ways to control them with scripting expressions. Emitters are the way particles are born into the scene( rate of emission, inital velocity...). Just like geometry objects, emitters can be placed on motion paths for effects like the one above.

Particles are what are emitted and they are a few types for different looks (dots, spheres, streaks...). Certain types can be rendered with the Maya software renderer, but most are done with hardware rendering, which takes advantage of the hardware on your video card (if you have a decent one). It's must faster than software rendering and with some motion blur and some post work, can look pretty great.

Forces are ways to control particles once they emit, such as gravity, wind, drag, vortex. In the above example i have gravity on the sparks so they tend to fall dowward but an upward directional force on the smoke to make it drift upward, as well as some turbulence to make it swirl a bit.

I would have loved to make it explode at the end, but we dont have that kind of time..on to the next lesson! : )

Week 8: Skinning

Been offline for a while since skinning week was really intense and not much time for much else. Unlike other weeks, there aren't that many examples to show as the concept is rather simple but the work is very tedious and difficult to do get exacting results without lots of work.

The term 'skinning' is not unlike the hunting term (where animal's skin is removed) but in this case we are putting on skin, not taking off. Just like a real person, characters have a skeleton with joints that move and the skin follows along. It's the same in 3d but..and its a big but..it the skin moving with the bones doesn't just happen automatically. One has to go in assign each vertex in the outer skin to a joint inside and then decide how much influence that joint has over that point. If its 100 percent, then moving that joint will make that point follow it 100%. if 50% assignment, then the movement of that skin vertex will move some average of that joint and of the position of whatever other bones of which that vertex is a member. When done correctly, arms bend and stretch correctly, wrists turn and everything behaves as it should. This kind of work is only noticible to most people when something doesn't look right. So it's kind of an invisible art. I think skinning and rigging artists are the unsung heros of 3d character animation.

In the image above, the white areas are showing 100 percent assingment to the elbow and black areas have no assignment, i.e. wont deform when the joint is bent. Grey areas have multiple joints assinged to the those vertices. The cool part is if you have a pen and tablet, like a wacom, you can paint these assignments with the pen using white and black colors. So literally you are painting the influence a selected joint has on the skin. It makes the process faster and more bearable then if had to just use a mouse or assign the numbers by data input. The red circle in the image is the brush shape i was painting with.

The finishing touches related to skinning include the use of deformers. Skinning itself is a deformation proces but with other deformers on top you can make a muscle flex when the arm is bent or correct and area around a joint that isn't deforming/bending propertly. Once assinged, just bending the arm will make the bicpes flex, etc. It's really cool.

In the clip above, I'm showing the calethenics test that characters are put through when doing skinning. It's the best way to see how things are bending and what areas need more tweaking. Also you can see me grab come small points called clusters which are a type of deformer I assigned to the areas in and around the biceps/elblow are to correct the bend and make the bicep flex when the arm is bent.

Not much else to say or show about skinning, as i said it's easy in concept but just lots and lots of testing and tweaking. I liked it since i got to feel some sense of painting again, but I don't think I would like doing it everyday for months on end.

Last (and coolest) week coming up: Dyamics :P

Week 7: Rigging/Kinematics - Set Driven Keys

Wrapping up this week we covered the last of the constraints, Set Driven Keys. For artist who aren't so versed in coding in MEL (or don't care to be), this was of visually constraining one objects value to another's is a godsend. That's the long and short of it really...we are telling Maya that when object 'A' is in this position or state, put object 'B' (or C, D or as many as like) in that position or state. You can even use Set Driven to connect an object's value to a slider control that appears in the work area so making a mouth open/close, wing flap is really easy.

In the screencap above, I wired the rotations of the joints of a hand to the position of crosshair's position. Moving the crosshair from left to right causes the joints to rotate and the hand closes. Then wired the positon of the locator to the slider I made called 'Grip' so just changing that value makes the same action. Having this kind of east control allows animators to focus on animating and not on finding objects in the scene and speeds up their workflow.

Week 7: Rigging/Kinematics - Ant rig

Rigging week was very interesting , but for me the most challenging week yet. You really need to think like an engineer and being really good at math doesn't hurt either. Maks, our instructor did a great job to trying to teach some tough material. My brain really hurt by the end of the week..haha. It is really fun though, trying to solve puzzles of how the get the relationship or control you want in skeleton or hierarchy.

In the above screen cap, I'm just showing a rig we worked on for class which is a skeleton for an ant, using IK (inverse kinematics) for the legs and FK (forward kinematics) for the spine. All IK means is that a chain of joints reacts/orients based on the placement of the end of the joint chain(effector). It's a quick method to pose arms and legs, but you lose the nice arcs you get with FK, like in the natural motion arcs of our arms and legs. FK, on the other hand, works by rotating the 'top' joint first (say the hip) and then then rotating the knee joint, then the ankle...etc. It's a lot of animating compared to IK. So much in fact, that IK is almost always done for a walk cycle.

It might be easier to see in the clip above. The legs of the ant are IK and the spine is FK. A good rig make the animator's job easier because he/she just have to move or animate a few controls and can access them easily. the circle's near the feet of the ant are an example of this.

Week 7: Rigging/Kinematics

This week we are doing rigging, which is the process of creating skeletons basically, for characters or mechanical objects. It's pretty involved and we are still working on creating a skeleton (or 'rig') for a character, so nothing to show yet : (. Rigging has always intimidated me a bit and it's one of the most, if not the most, technical area of 3d, but Maks (our instructor) is doing a great job making it easier to understand. He is a super talented guy who has worked on many motion feature films as a rigging artist for Beowolf, Bad Boys, Matrix, Stuart Little, Harry Potter, just to name a few. Check out his film credits here... feel lucky to have such an experienced instructor. : )

more later!