Physics and Dynamics3D Animation & Realism

COMPUTER GAMES

Monday, 16 June 14

Basic informationComputer animation physics or game physics involves the introduction of the laws of physics into a simulation or game engine, particularly in 3D computer graphics for the purpose of making the effects appear more real to the observer. Typically, simulation physics is only a close approximation to real physics, and computation is performed using discrete values.

There are two central types of physics simulations; rigid body and soft-body simulators. In a rigid body simulation objects are grouped into categories based on how they should interact and are less performance intensive. Soft-body physics involves simulating individual sections of each object such that it behaves in a more realistic way.

Monday, 16 June 14

There has been a tendency, especially within big Triple A rated games, to make 3D Animation more realistic. With advancements in physics engines coupled with Motion Capture are now the go to tool in the industry for making realistic & believable human behaviour in games. However, it was a long process to get to the stage we are at now, now being the “Next-Gen” stage. There are still some problems or “Limitations” that still occur with the use of Motion Capture systems.

3D Animation

Monday, 16 June 14

Problems with Body Motion Capture

For the most part Motion Capture has the ability to capture actual movement, through use of body actors and body suits, very well. However, there are just a few disadvantages that come with that. Whilst having realistic motion is always a bonus, its now made it even harder to use in games, as games at their very nature are not meant to be real.

The article below states that it is tricky to combine & adapt to certain situations. Such as environmental factors, questions about how does realistic action fit within computer generated worlds need to be raised. Major games that use this are games such as GTA 5, WATCH DOGS & ASSASSINS CREED. What these all have in common is that the realistic motion works because of the very realistic environments, be it modern day or historic are all man made, thus fitting and working well with Motion capture. However, what if the world the game was set in was not contemporary or even Earth. How would they transfer over then?

http://www.cs.jhu.edu/~cohen/RendTech99/Lectures/Computer_Animation.color.pdf

Monday, 16 June 14

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

According to the wikipedia entry above, movements that do not follow the natural law of physics cannot be captured in Motion capture technology. This provides problems for when a captured sequence needs to have added to It, an un-natural movement.

The clip features an ability you can perform in the game Assassins Creed : Revelations, a movement called a hook and run, where you can use Enzio's hidden blade to hook over an opponent to escape. Watch the jarring action between the natural running motion, captured with Motion Capture, and the un- natural Hook and run, which was created using animation you can clearly see a difference.

Problems with Body Motion Capture

Monday, 16 June 14

Problems with Body Motion Capture

http://www.techradar.com/news/gaming/motion-capture-is-the-death-of-half-life-3-alleges-voice-actor-john-patrick-lowrie-1173697

The magazine article above raises some other issues with Motion Capture technology in relation to the the game Half Life 3. The Half Life series is meant to give players the freedom of controlling the direction of the plot and storyline. Whilst you will all meet at the same ending, decisions taken by players may affect the progression of the story of the game. That makes us part of the problem in that making the gameplay based on motion captured actors, instead of using animation to create the different possibilities in which the player can control a character, motion capture means you are simply limited to that was captured in Motion Capture process. This makes for an extremely ambitious game.

Monday, 16 June 14

Problems with Facial Motion Capture

Despite the challenges listed in the previous section,body motion capture has made far more significant strides than facial motion capture.The resolution and detail required to create accurate expressions & facial features are far greater than those needed for body motion capture.

http://www.develop-online.net/tools-and-tech/motion-capture-moving-with-the-times/0117523

In the article above it states, “The real challenge according to Mick Morris, MD of mo-cap service provider AudioMotion, however, is a matter staring the industry in the face. The human face is, of course, the most expressive part of our body, and at the very centre of almost any performance. Captured incorrectly, it can let an entire game down, and it is still tough for mo-cap solutions to grasp the essence of.”

Monday, 16 June 14

Facial Motion Capture

As you will see in the video link below, the character animators for the big Triple A game 'The Last of Us' developed by Naughty Dog studios, use the facial expressions, performed by the body actors, as a guide but not as the piece they edit. They create the facial features from scratch. The animators said they get to create far greater detail by adding features and expression manually frame by frame. So like with anything, it has its drawbacks. However, Motion Capture is by far the way forward for animation in video games.

http://youtu.be/R0l7LzC_h8I

Monday, 16 June 14

More Examples of Physics and Dynamics

RIGID-BODYRigid-body dynamics studies the movement of systems of interconnected bodies under the action of external forces. The assumption that the bodies are rigid, which means that they do not deform under the action of applied forces, simplifies the analysis by reducing the parameters that describe the configuration of the system to the translation and rotation of reference frames attached to each body.

SOFT-BODYThe applications are mostly in video games and film. Unlike in simulation of rigid bodies, the shape of soft bodies can change, meaning that the relative distance of two points on the object is not fixed. While the relative distances of points are not fixed, the body is expected to retain its shape to some degree, unlike a fluid.

Monday, 16 June 14

RIGID-BODY SOFT-BODY

Monday, 16 June 14

PARTICLE SYSTEMSA common aspect of computer games that model some type of conflict is the explosion. Early computer games used the simple expedient of repeating the same explosion in each circumstance. However, in the real world an explosion can vary depending on the terrain, altitude of the explosion, and the type of solid bodies being impacted. Depending on the processing power available, the effects of the explosion can be modelled as the split and shattered components propelled by the expanding gas. This is modelled by means of a particle system simulation. A particle system model allows a variety of other physical phenomena to be simulated, including smoke, moving water, precipitation, and so forth. The individual particles within the system are modelled using the other elements of the physics simulation rules, with the limitation that the number of particles that can be simulated is restricted by the computing power of the hardware. Thus explosions may need to be modelled as a small set of large particles, rather than the more accurate huge number of fine particles.

Monday, 16 June 14

Examples In Gameplay

Monday, 16 June 14