Chapter 7 OverviewAlthough the project itself was an exercise in creating a virtual set for animated use, an animation was produced to show the city as a set. The sequence that was created is a compendium of shots from various animations that would have used the city as a set, and as result has no storyline as such. This can be likened to a promotional video for a production studio. The sequence was animated to fit the soundtrack chosen, which was decided to be a piece from Channel 4’s series ‘The Lonely Planet’ entitled ‘Natya Sastra – Dramatic Science’. The soundtrack worked very well to give the desired feel, although a small amount of editing within Sonic Foundry’s SoundForge application and Adobe Premier was necessary. This chapter aims to give a general view of how certain parts of the animation were completed to give the final sequence. This chapter will also show the variation in animation methods used throughout the final sequence. A Tribute to Universal Studios
If there is one movie company that
has done more to bring the mystery and magic of Ancient
Egypt to the imaginations of the general population then
Universal Studios has to be it. There have been over 200
films made about ancient
As a tribute to Universal Studios it was decided to have the opening of the animation parody the famous title logo sequence used by Universal at the beginning of each movie. The only area to be changed would be the word ‘UNIVERSAL’ into ‘UNIVERSITY’, as this is a university project The sequence itself was fairly easy to recreate. A sphere was mapped with an image of the Earth to create a globe, which was then animated to rotate very slowly. At the centre point of the globe an omni light was placed. The omni light had its attenuation set to falloff a little beyond the globe’s surface. In the environment rollout a volume effect was attached to the light and given orange and yellow colours to represent the fiery rays that are seen to travel across the globe in the original Universal sequence. A copy of the original sphere was created and, with the texture visible in the viewport, edited to remove random faces where the continents lay. When the normals were inverted the geometry acted as a 3d mask for the volume lighting. Animating this mask allowed the volume light effect to travel across the globe. The text
was created by finding a similar font to the one used by Universal and editing the resultant spline to create as close a facsimile as possible. This spline was then extruded and animated along a path in order to orbit the globe. A camera was set up to pull back from a close up shot of the globe, and in the Video Post box a star field was composited into the background. The sequence was given image-motion-blur to complete the animation. Daytime in Amarna
This sequence, lasting approximately 20 seconds, was probably the most time consuming to create. The sequence itself was not technically demanding in itself, once the city model had been built and textured it was simply a case of animating a camera fly-through. The main problem was in the render time of around 30 minutes a frame, which meant that the scene had to be correct before committing to over a week of computer processing. The frame time was not thought to be too bad given the fact that the scene consisted of over 4 million polygons and detailed shadows. The render time would have been increased dramatically if automatic reflections had not been disabled, but as the sequence did not merit from any reflective surfaces, this was deemed necessary, even though the river is still viewable in the distance. The sequence was originally meant to incorporate crowd animation, but as time was against the project, and the crowd system had not been completed at this point, it was thought that this may be possible to add afterwards in post production. Unfortunately, this was not the case and the crowd system was to be used elsewhere. Rendering this part of the animation became problematic when the computer system consistently crashed after only a few frames. A careful examination of the scene showed that some of the textures where unnecessarily large increasing the memory overheads quite considerably. After the offending textures were resized, and some non essential geometry deleted, the software stabilized and the rendering could continue with minimal interruption. The Priestess and Anubis Affair
The idea behind this piece was derived from the decree Pharaoh Akhenaten made during his reign. Akhenaten outlawed the worship of all other gods in favour of the Solar Disk – Aten. This eventually led to the destruction of the city of Amarna and the erasure of his name from nearly every monument in an attempt to wipe him from all eternity. This sequence takes the idea that without worship there are no gods, and that the exiled deities were about to fight for there very existence. The original piece was to have various deities materializing into ‘real-life’ using the methods that they were worshiped for, in some cases this would have been the well known ‘Earth, Wind, Sea & Fire’ properties. The sequence shows a priestess walking, trance-like, through a hidden dark inner sanctum of some temple, passing images of various deities, until she reaches ‘her’ god – Anubis. As Anubis is the god of the underworld and embalming he needs living energy to bring him into the ‘real-world’. The priestess offers him her life-force and he materializes within the sanctum.
The decision to create this sequence with Anubis was due to his recognizable features as an Egyptian God. He was created as a spline cage and converted into polygonal mesh for animation with Character Studio. The priestess was modeled in a similar fashion and also animated via Character Studio. The walk for the priestess was created using the footstep system, in order to quickly block out the motion, and converted into freeform mode to give an individual motion to the character, tweaking the animation by hand. As Anubis doesn’t walk anywhere in the sequence, all of his animation was completed in freeform mode. The effect of Anubis materializing from the wall freeze was created entirely within 3dsmax without any external post-production. To accomplish this, effective use of the Material Channel and the Geometry Buffer where called on. First the image of Anubis used for the wall freeze was traced into splines within 3dsmax and extruded to give a solid geometric outline. The outline was then distorted along its z-axis slightly, using a noise modifier. When animated passing through the wall from behind, this would allow parts of the outline to appear at different stages, giving a ‘bleeding’ feel. The effect was finished off by adding a glow to the outline keyed off the G-buffer, whilst keeping the object invisible. A similar approach was taken with the Anubis character, as his visibility track was animated a separate glow was keyed off his G-buffer. The hot coals, seen as the priestess walks past, used a variation on the glow effect by using the Material Channel within the objects’ texture to key off. The glow size was animated with the addition of a noise modifier and synchronized with the movement of the omni lights placed within each pyre, to give a subtle variation from the hot coals.
Multiple camera angles were rendered and cut together using passing columns as the basis for each transition. The final piece shows the priestess bringing Anubis into the ‘real-world’ and his realization that he ‘exists’. The Bugs
This was the first attempt at generating crowds using Character Studio. The idea behind this piece was a follow on from the destruction of Amarna theme, where in this case the city becomes infested with demonic bug-like creatures from the underworld. The bugs were created from spline cages, optimized and converted to polygonal geometry. The body parts were linked together in a hierarchical structure and given basic animation for flight. In addition to the crowd system, a dynamics system was implemented in order to create the falling slabs which release the bugs.
The Crowd system is implemented in two parts, and is accessed via the Create > Helper tab in the Main Command Panel. The system is comprised of a Crowd helper, which is basically a complex behavioural particle system, and one or more Delegate helpers, which are more like intelligent particles with there own built in dynamics attributes. The Crowd helper can be placed anywhere in the scene in the form of an icon and works as the controller, whilst the Delegates take the form of small pyramid shaped objects with the point tip being the direction of forward motion. The Delegates are eventually linked to the geometry that is to be animated.
Once a Crowd helper object and a Delegate have been created within the scene, the next step is to use the Scatter tool within the Crowd rollout to create the necessary number of Delegate clones for the simulation. The Scatter tool can also be used to set the initial position and orientation of the Delegates. It is at this point that the Scatter tool can be used to create clones of the geometry objects for animation. When all the parts of the simulation have been created then the next step is to create associations between the Delegates and the geometry, this is done within the Object/Delegate Associations dialog box within the Crowd rollout. This is an important step as it also aligns the object to the Delegate, preventing objects moving sideways or backwards. Although each Delegate can be given it’s own motion weighting the Crowd rollout has a feature for editing multiple Delegates in one go, a very useful feature when there are many Delegates within the scene.
When the system has been set up as described the next main step is to give the Crowd behaviours. In the Crowd rollout there is a behaviours box, this will allow various behavioural algorithms to be attached to the system. By pressing the ‘New’ button a list of available behaviours can be found, each of which has its own rollout and settings which can be modified later by accessing the relevant behaviour from the drop down list box in the Crowd rollout. One of the most important behaviours is ‘Avoid’, without this all the delegates would pass through each other taking their associated geometry with them. Other behaviours needed for the bug sequence included ‘Wall Repel’ which when used with non-visible grids, for collision detection, prevented the objects flying through the city walls and ground plane. ‘Seek’ behaviour was coupled with another invisible object in order for the bugs to have some direction or purpose in their flight. Finally the Delegates were grouped within a ‘Team’ and the behaviours were assigned to the team. This is a useful feature if the animation requires differing actions by certain Delegates as there can be many groupings into various behavioural teams. The Gateway to the Underworld – AKA The Broken PatioThe Bugs needed some entry point into the sequence and so this was provided by a rift opening up within the Palace Courtyard. The sequence included a dynamics system where 400 geometric blocks were animated falling into a void. Reactor is the dynamics simulator now built into 3dsmax. It is a very accurate system including soft & rigid body dynamics, cloth simulation, ropes and water. For the purpose of this sequence rigid body dynamics was used to create the animation for the falling blocks.
The blocks were created by creating an array of a single edited mesh box. A small offset was added to each box in the Array Panel in order to assist with collision detection in the dynamics simulation. The dynamics system is accessed via the Create > Helper tab within the Command Panel. An RBCollection (rigid body) helper was created within the viewport and, in the rollout; all 400 blocks were added to simulation via the collection list. The main Reactor simulation control rollout can be found in the Utilities Tab within the Command Panel, from there the simulation is given additional properties such as gravity and weight/density. This is also where the simulation calculation is executed. After the simulation has been calculated you are given the option to reduce the keys within the animation – a good idea when there are a large quantity of objects. 2’s Company – 51’s a Crowd
The crowd sequence was an interesting piece to work on. The method used was very similar to that used in the bug sequence, but instead of the ‘delegates’ controlling pre-animated bugs, this time it was a more procedural approach using bipeds and motion flow scripting.
The idea behind motion flow scripting is quite simple, but can lead to very complex animation being produced. First, all of the moves, needed to have a biped walk around, are created and stored as separate *.bip files, which is Character Studio’s native motion capture format e.g. ‘walk_start.bip’, ‘walk_stop.bip’, ‘walk.bip’, ‘walk_180.bip’, ‘walk_bendleft.bip’, ‘walk_bendright.bip’, ‘walk_L45.bip’, ‘walk_L90.bip’, ‘walk_R45.bip’, ‘walk_R90.bip’, ‘loiter01.bip’, ‘loiter02.bip’, etc.
Once all the separate motions have been created, they are then compiled into a motion flow script; this is a list of all the possible transitions that can be made from the available motion files. Fortunately this is achieved quite quickly by using the built-in visual motion flow chart tools. The next step is to associate the bipeds with the crowd system delegates, add a few behaviours then click the ‘solve’ button. The crowd sequence was also an exercise in compositing. To minimize the time spent rendering the crowd animation and the city it was decided that background plates would be rendered and the crowd sequence would be composited onto the plates. In order for this to work correctly the crowd figures needed to be able to cast their shadows onto an invisible floor. A shadow/matte floor was created using low resolution geometry from earlier builds of the city and 3dsmax’s built in shadow/matte material. The camera which rendered the background plate was used to set up the crowd scene for rendering. Originally the idea was to have more of a variation in the crowd, e.g. women, children, priest’s etc. Unfortunately there was no time left to implement these for this project, however, the system was proven to work and plans are underway to exploit this in the future.
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