in asociation with BBC Film Network and BBC

Modeler.

Modeller
London. ENGLAND

I had the pleasure to work in this short film, by Peter Szewczyk, modeling the humminbird

here the shortFilm Colour Bleed

Modeler.

I had the fortune to work in this amazing project. I did work modeling characters, environments and props.  Also cloth, hair, and several statues mainly sculpted in high detail with Mudbox.

The detail in every model was total, and the amount of work done for this project like never seen. We took part in a whole process of building a complete city thanks to the FX department. These guys developed their own procedural city system, where we supplied just the assets, they did the rest. A must seen

An amazing environment, direction and all possible technical resources, training and support for a best performance and indeed a top quality work to be proud of.

Well the movie will say this better than me. Sure is not for missing it.

here the website and trailer

web

]]> http://www.asepulveda.com/2010/05/megamind/feed/ 0 http://www.asepulveda.com/2010/05/shrek-forever-after/ http://www.asepulveda.com/2010/05/shrek-forever-after/#comments Sun, 09 May 2010 23:47:32 +0000 admin http://www.asepulveda.com/?p=971 Dreamworks Animation

Modeler.

Just arrived to PDI Dreamworks and have the chance to work in this sequel, but in my opinion probably the best of all of them. Sadly an started project already so I worked mainly in environment and props, but some small characters as well.

The attention to detail and elaboration was a new challenge for me. Of course a big name behind as Shrek and a good budget to do things the best possible. Art direction over every possible improvement on the models.

The final result even for props or environment amazing, Drewamworks !!! what more

website

Character Modeler and Lighter.

Character Modeller // Lighter
Framestore Animation – London. ENGLAND
Character modelling, Facial Shapes, Lighting

This movie is from Universal Studios being done by Framestore Animation (UK).

I worked as a Lighter using Renderman. It was  such a challenge and great experience due to the complex pipeline we were working with.

The look required the usage of a number of CG features like: fur, crowds, and others, made it such a big complex project with an amazing result.

Some Lighting examples

Before going to the lighting department I worked as a Character Modeler,  taking care of topologies design and also Face Shapes. I did work on some main characters,  secondary and crowds, male humans and rats.

Most generic humans and some of the secondary characters were built using the same mesh topology. This allowed us to transfer the facial blendshapes easily from one character to another.

Some models samples

The King

Boticelli

Pietro

Guards

Uncle Ned

Town Crier

Crowds

And also some environment and props….

The Tale of Despereaux

by Armando Sepulveda

Introduction

Modern 3D scanning technology is widely used in CG production as a first step in the creation of 3D models. Despite the current advances in existing tools, it is still a non trivial process.

One obstacle is that some models can not be scanned in a single pass due to its complex form, in such cases it is required to break apart the model and then scan each part separately. The modeler artist is then responsible for rebuilding the original 3D model from the scanned parts.

However a for more difficult issue one must deal with is the clean up of the scanned 3D data. We need to adjust the resolution of the model to the production needs of the project and more importantly — specially in CG animation — the whole topology of the mesh data must be revised to allow proper deformations. By topology we refer to the flow of polygonal lines, vertex count of its intersection and the overall layout of these features on the 3D model

Overview

The objective of this article is to present a production tested workflow for the conversion of scan data into a valid 3D geometric and topological structure for CG animation. We will also cover the specific problem of dealing with multipart scans.

Our workflow is based on well known commercial packages: Maya, Nex, Mudbox and Photoshop.

Thanks to Mudbox or ZBrush we will be able to translate our scan data into a hierarchical subdivision surface, where it is far easier to model low resolution detail working on a low count polygonal mesh and at the same time we can still add highly precise detail in the higher res version of the same sub surface. All this switch back and forth from low to high resolution in a seamless manner.

We nevertheless can benefit from using extra software like Topogun. However let us leave for the moment the details of how to use these plugins for a future article.

#step 1. Importing the data

We are going to assume that the 3D scanning department is going to provide us with several resolution scans of the parts in the model. This is by far the most common work routine. In the example bellow, for example, we are going to have a low and hires versions of the left arm, right arm, torso, etc.

We need to bring all this data into our maya environment, scale it, oriented properly and setting all the parts in place.

Since working with potentially millions of polygons for the main body, scaling, rotating etc is very cumbersome and potentially slow process we are going to use a simple trick in maya to do the job once in the low res and apply it on the highres for free.

So here are the first steps:

- Open Maya and import the low res version of the scan

- Use Ctrl:g to assign the geometry to a new group

- Now select the newly created group and transform its scale, orientation and position until the model is place in the desire target location and scale.

- Lock the group to prevent modifying its transform by accident

#step 2. Transforming the data

Next we are going to reuse the group we just created to apply the same rotation, scaling and translation operations to other parts

- Import the next part of the model into maya

- Parent it under the previous group node

- Reset the transform of the new part so that it gets move to its proper location

In the next figure we added an skeleton to the maya scene in order to verify that arms, joints and proportions are all correct.

#Step 3. Organizing the data

The parts of the model we are importing can be organized in very complex hierarchical structures in order to have the flexibility of changing the pose, for example rotating an arm. One can then create a number of groups under the first root group for this purpose. Always keep an important detail in mind: set the pivots of the new groups in the appropriate locations.

In the case shown in the next figure, we rotated the RightArm group after resetting it to the proper location attached to the torso. Now when one imports the hires version of the same arm, and parents it/reset it under this transform it should go to the same exact location and orientation.

-We can create specific layers for each LOD and parts into the scan data for a better control.

#Step 4. Modeling the geometry

Next we are going to use a maya plugin called Nex to create a cleaner version of the same model. This plugin allows us to re-sample the scanned data and generate geometry with the desired resolution and topology.

Before proceeding there is an intermediate step one has to take care first. Since we rotated the location of the arms, the joint shoulder scanned data doesn’t match exactly anymore. Using Mudbox this is easily fixable.

Just creating a low res version of the model with a correct topology is enough. It’s not necessary to match every detail on the scan data right now. Later on, Mudbox will take care of that baking the high res data into the low.

NEX Plugin

Nex is a plugin for Maya very handy for modeling over live surfaces. Take a look at this link and its videos, mainly the Quad Draw Tool.

Draster

I’ll be using the Quad Draw tool. So first thing is setting the mesh as Live Reference.

After setting the scan as the reference, every vertex, edge or polygion we create or move will be snapped to the surface. The Quad Draw tool allows you to create vertex freely on the surface and then create the polygons with them.

It’s very easy to combine the maya tools with Nex, so just extruding an edge and then Shrink it to the Live Mesh.

Most of main modeling tools are already included into Nex. So even when we add loops they will be snapped automaticly to the surface.

And finally after creating and editing, and always keeping the volume, I have a final (almost) low res mesh with a proper Topology. For a better explanation about topologies go to this post where I give some orientation or ideas.

Topologies in Production

#Step 5.Uvs

Using a right topology and flow will make things easier for the time we create the uvs.

I’ll create a symmetrical modell, so I’ll have as well symetricall uvs, therefore I’ll have to place them in the center of the uv space ready to be mirrored.

Our final Uvs

#Step 6. Baking the Scan Data

Now we will transfer the volume info from the scan to our clean Mesh getting a Displacement Map to work with. Our goal is to mirror this map and apply it back again to the mesh obtaining a final HighRes mesh with subdivision history into Mudbox.

It’s also the time to use the high res scandata exported from Maya, following the intial steps to get its proper transforms. This scan data is closer to 1M polys

Due to the rotation in the arms it will need some modeling work in Mudbox, as well as some cleaning on the surface before baking it.

Once ready the Highres Scan we import our low res geo with the right topology and uvs. We named everything properly into Mudbox and we baked it.

Utilities/Texture Baking/New Operation and these are the settings

We can use the Image Browser to check our final Displament Map. After that we will mirror it and get a new complete and symmetrical map.

We bake back this mirrored map into the Low res Geo to get our Subdivided mesh.

Utilities/Mesh Displacement/New Operation and these are the settings

#step 7. Final Touch

Of course once the Disp Map is mirrored and baked back to our geo we will get some artifacts, so we will have to do some cleaning.

And here is the final result with the different levels of detail.

After that, our final model can be baked back again into our Low Res Geo and get a final clean Displacement Map ready for render, and of course another new Low res Geo matching the volume of the Scan.

Here is a Maya snapshot with the final Low res Geo and a clean topology ready to be rigged and animated.

]]> http://www.asepulveda.com/2008/07/working-with-scan-data/feed/ 0 http://www.asepulveda.com/2008/07/topologies-in-production/ http://www.asepulveda.com/2008/07/topologies-in-production/#comments Tue, 15 Jul 2008 13:57:30 +0000 admin http://www.asepulveda.com/?p=157 direction about the right topology in production

by Armando Sepulveda

Topology introduction

I don’t think there is a perfect topology and each production could require an specific topology design. Feature Animation, Film, Video Games, they all work in a total different way at the time of moving and deforming models, therefore with different topologies necessities. Even based on the engine Mental Ray, Renderman, etc, topologies might require some specific designs in order to be rendered properly. So, there is always and special situation for each model and topology design, but anyway there are some conditions to follow to do a better model.

As a modeller and understanding how a pipeline/workflow works into a production, is important to have in mind who is coming after us to work on the model, what the character (in this case) is suppose to do or even for later cleaning, editing, etc.

Sometimes a better topology makes easier and faster to change the geometry based on the requests coming from other departments or even Art Director/Director. Adding loops, removing them, adding details, etc. Sometimes even reusing the geometry to create a new character.

Probably the most important aspect in a topology is that gives a perfect deformation when the character is rigged and animated.

Here is an screen shot of a realistic rigged hand. Is NOT a modelled pose, this is the deformation coming from the rig (here is a link to a post about this rig setup by Igor Stefanovic)

Hand Study Rig

Depending on the complexity of movement, flesh or sliding skin, or even the category of the CG, Film or Feature animation topologies could differ. Here you can compare two examples of them.

In both cases the flow of loops goes in the direction of the foldings, helping a better deformation

We also know that the model will be subdivided and in this process some surface artifacts might show up, because a wrong topology, triangles, wrong reductions, extraordinary vertex (more than four edges) in the wrong place, etc. So a clean mesh will result in a smother and more controllable surface

Some models could be deformed very well, but very hard to tweak, or even to be reused. So our challenge comes when we try to reach all this necessities.

It’s impossible to avoid vertex with more than four edges, where several flows meet in one point. We called this vertex “extraordinary vertex” of in nurbs “five patch corner”, and is there where all this patches are stitched.

I follow as a rule trying to keep them in a same loop.

Well if we were working in nurbs ther is no other way, but talking about polys is just because makes easier to edit, tweak, reuse or even combine with other geometries. Lets say an ear, that we can just separate and take it to another head.

Adding or removing loops won’t be difficult at all, if some department ask for that. Here is an example

So, the main difficulty is giving the right volume and interpretation at the same time we follow just a few rules, to make the geometry more effective and these are those rules.

A. Flow direction based on volume and deformation

B. Continuity between extraordinary vertex

C. Clean geometry avoiding triangles or any other different than a four side polygon

D. Patch modelling or defined areas

Here some production examples

Armando Sepulveda Modeling

HUMAN HAND STUDY – A DEFORMATION RIG DEMO

Introduction

In a production environment, it is important to have a rigging pipeline that provides high quality output, and enables easy corrections and finalling. On projects involving multiple characters, it is also important to provide easy portability between characters. Designing a system with these requirements in mind can be a huge benefit in productions, where time is always valuable resource.

This is an overview of such a system, demonstrated on realistic human hand. The system consists of several components, and I named it The Tracker System.

Final deformed NURBS model, and a view of the Tracker System, used for tweaking pose-specific deformations.

Overview

Tracker system is a pose based deformation system. It consists of deformation joints parented to animation joints, set of pose readers which read rotations of animation joints, and trackers which define behavior of deformation joints based on poses.

Deformation joints are assigned to low resolution cage geometry, which is a simplified version of final model. It is designed to have one deformation joint for each vertex, for easier weighting process and to make deformation of final model smoother. This way weighting process is very short and routine. Also, it is important to place low res cage vertices strategically, since deformation of final model depends on their positions.

Low resolution cage, used as a driver for final high res model. Topology is designed to follow deformations.

At the end, low res cage is deforming final model as influence object. Since cage is matching model in shape and volume, final behavior is very accurate without additional corrections.

Pipeline

Here is the overall graph of the pipeline:

Animation joints

A standard fk/ik skeleton representing bones in character’s body, which is used for animation. These joints are parents to all deformation joints.

Pose readers

A set of nodes used for measuring relative angle between child and parent animation joints. These angles are converted to pose values between 0 and 1, similar to target values for blend shapes. For one-dimensional rotations (such as in fingers, elbow, knee) there are usually two reachable poses (in pose and out pose). For two-dimensional rotations (thumb base, clavicle bone) there are four reachable poses (e.g. in, out, up and down). For three-dimensional rotations (shoulder, wrist, hip, ankle) there are four directional poses (in, out, up, down) and two additional twist poses (in twist and out twist). The outputs of pose reading system are values between 0 and 1 for each of the poses for a specific animation joint. These values should be exclusive, so that total sum of pose values for a single animation joint is 1.

Pose reader attributes are converting rotations to pose values, and setting the threshold for pose trackers visibility.

For one-dimensional rotations, these values can be set up using simple set driven keys. For two-dimensional rotations, system should be able to avoid gimbal locks of animation joints, by using quaternion rotations or a prebuilt pose reader like Comet Pose Reader. For three-dimensional rotations, system should be an upgraded two-dimensional reader which reads twist on top.

Deformation joints

They are created procedurally, based on positions of specific locators. That way, by repositioning the locators, system can easily be rebuilt for multiple characters. In one point, there are usually multiple deformation joints, and they are organized into specific hierarchy:

Generic deformation joints hierarchy.

Main deformation joint places the hierarchy into specific position in space (defined by locator), so in default pose all its children are matching its position. Underneath it, behavior of each of deformation joints 1 through n can be influenced by different pose reader. For instance, a single point in shoulder area can be influenced by spine rotation, spine twist, clavicle rotation, shoulder rotation, breathing, jiggle etc. Each of these deformations needs to have its own joint in hierarchy. So the position of last joint in hierarchy, final skinning joint, is defined as a sum of translation vectors of all deformation joints in the hierarchy.

In the hand example, these combinations of influences are most pronounced in palm and thumb base areas.

Example of deformation hierarchy for a joint in thumb base area, including deformations dependent on wrist, base of thumb, and middle thumb segment.

Tracker system

Is used to define the behavior of each deformation joint in the hierarchy.

Each deformation joint has a tracker group associated with it, parented to same parent and in the same position in space. This group contains tracker objects, which are standard nurbs geometries. There is a single tracker for each pose associated to specific deformation joint.

Translation of each tracker is multiplied by relevant pose value (by multiplyDivide node), and added to the final translate value of deformation joint (by plusMinusAverage node):

Final position of a single joint is a sum of all pose offsets.

Visibility of trackers is connected to pose values, so they automatically become visible once rotation of animation joints passes certain threshold.

The resulting workflow means going through all poses by rotating specific animation joints, and for each pose tweaking translation of related trackers.

To speed up the process, dependencies between deformation joints are added on top. This is achieved by adding more elements to plusMinusAverage node which controls translation of deformation joint. These elements are translation offsets of neighboring joints, multiplied by influence value between 0 and 1 to decrease effect. In this way a specific deformation joint can have dependent behavior from neighboring joints plus its own independent behavior. This allows to have several major deformation joints to define rough shape and more dependent joints to tweak details, and yet to preserve fast workflow.

Final position of a single joint can include dependencies toward the neighboring joints.

Here are the steps of the complete workflow:

1 – Model the low res cage;

2 – Snap the deformation locators to cage vertices;

3 – Procedurally create animation joints;

4 – Procedurally create pose readers;

5 – Procedurally creaate deformation joints with trackers;

6 – Procedurally create depencencies between deformation joints;

7 – Procedurally assing low res cage to all skinning deformation joints;

8 – Go through all poses for all animation joints and tweak the trackers;

9 – Assign low res cage to high res model as influence object and check final deformations.

Perspective: Combining The Tracker System with muscle-based deformers

Muscle dynamics provide good deformations in areas around middle of the bones in body (such as biceps and triceps areas). However, in areas around joints and knuckles, especially if there is a significant amount of freedom in rotation, it is easier to manually correct behavior and deformation. That is why a system like The Tracker System, which provide a large level of control over behavior, delivers better, more predictable, and more optimized results.

Integrating The Tracker System with muscle behavior such as jiggle and contractions will be demonstrated in a full body setup which will come shortly. Also realistic face rig is on the way, using the same principles to create per-muscle expressions. In here, trackers are also used for tweaking deformations, and pose readers are not measuring relative angles, but expression targets which are animated.

Here a link to the Cgtalk article:

http://forums.cgsociety.org/archive/index.php/t-675068.html

and a video demo of the deforming rig and process:

http://www.igorstefanovic.com/demoreel/IgorStefanovic_handStudyReel2008.avi

Character Modeller using Zbrush creating high res models based on ILM movie.

Senior Modeller
Eurocom Entertainment – Derby. ENGLAND
Character modelling, Facial Shapes,

This game was done by Eurocom Entertainment (England).
Client: Disney

I worked as a Character Modeller, modeling High res and Low res Models, as well as Face Shapes, to be mixed with the Motion Capture animation data. After a very detailed modeling using Zbrush we have to bake several maps to be added to the low res model into the engine. Normal maps, Ambient Occlusion, diffuse or even specualr maps were baked all from Maya.

We did the generic women for the game, divided in three main peaces: head, torso, and bottom. We did several versions of each of these parts that could be combined between them. The engine will do a random to combine them creating its own versions.

Here is a capture from maya with Normal Map aplied and organization of this variants

and some examples of those random combinations

Some captures from the models I did for the game

]]> http://www.asepulveda.com/2006/12/pirates-of-the-caribbean/feed/ 0 http://www.asepulveda.com/2006/02/don-quijote/ http://www.asepulveda.com/2006/02/don-quijote/#comments Fri, 17 Feb 2006 16:50:28 +0000 admin http://www.asepulveda.com/?p=325 Bren Entertainment / Filmax Animation
La Coruña (SPAIN)

Character Modeller, Lighter and FX

Senior Modeller // Lighter // FX Artist
Bren Entertainment – La Coruña. SPAIN
Character modelling, Facial Shapes, Lighting FX

In Donkey Xote I did Character modeling and Face Shapes. Some samples of my work in this movie

Don Quijote (first version)

The Duke

James

After modeling I moved to Lighting/FX. In these shots I did the lighting, some vegetations and other Fx as well.