Monday, September 29, 2014

Term Paper - Archeage Physics

In the world of video games physics can be easily bended.  Sometimes it is intentional for the immersion of the video game like moves that disable your gravity, or a roundhouse kick that sends you across a massive room. Other times you can confuse the physics engine’s force detection and calculation which end up adding forces to a particular object that should not exist in the first place.  I have solid evidence that such exploits or perhaps immersion techniques are used in the video game Archeage Online.
                One of the transportation methods in Archeage is the ability to deploy a glider and use it to ride the wind for great distances and sometimes when it feels there is no wind at all.  However if you ride the glider for too long or decide to put the glider away while midflight the obvious happens, you fall to the ground.  I hypothesize due to the laws of gravity that during a freefall upon reaching the ground my character will die or be critically injured in the process.



                As you can see during the freefall I activated an ability that allows my character to do a backwards dodge.  This removed my entire downwards momentum and instead somehow generated a force in the reverse direction out of the air.  In the real world for someone to experience what just happened there must be a force given back by an object strong enough to propel one that far, something to exert a force back on my character.  In Archeage this is not the case. When the ability is activated the physics engine grants the character a force in said direction.  Also as you may notice a bit of damage was incurred by character but not enough for it to be lethal and far from life-like.  This was the momentum my character gained from the end of my ability and as you can see the downward acceleration from gravity was nullified. In a real world situation if one somehow managed to experience such a force to propel them backwards they would feel the same amount of pain, or death, regardless of the forces acting in the orthogonal directions. 
                Another transportation method in Archeage is the ability to traverse the open seas in a boat which come in different shapes and sizes.  The boat I am manning in the next video has a harpoon attached to the front intended to grapple on to other boats so you can board and plunder them. However something that is not intended is the ability to fire the harpoon to the sea floor, and pull oneself under.  Isolating the physics of the boat only I hypothesis that the boat will continually sink once it has been submerged by the harpoon cannon.


                Honestly the actual outcome was more entertaining that watching a boat sink.  In the real world the boat would sink because the boat is heavier than water and the buoyancy of the boat is negligible if there is water on the deck.  Once water has made it aboard the boat, once there is enough of it, it will weigh the boat down and lower its potential buoyancy until the point where it will just continually sink.  The physics in Archeage does not calculate it that way.  The engine is told that the object you are on is a boat and as such it is to float weightlessly on water. Should it be in contact with water the physics engine will repel the boat. When the whole boat becomes submerged the calculated physics when the harpoon line is cut is the repel force is massive since the boats position has already been moved so far underwater and such the boat experiences that massive force away from the water. 
                This video also brings up a lot of other physics based anomalies.  Such as the fact that the harpoon is hand cranked. Can you imagine the amount of torque a human would have to apply to a harpoon to completely submerge such a big boat? Or perhaps how my character’s stance did not change as she was tilted 90 degrees.  Did my character experience any force by the water as she was pulled under?  Many games do not implement these physics phenomenons into their engine because it would be too hard to calculate and keep track of all of them at once.
                For my next trick I shall attack a fellow enemy player by using a skill called Bubble Trap and experience its effects.  I hypothesize that my victim will feel the effects of the bubble trap and be suspended and unable to move.  This experiment, unlike the other two, bends real world physics for the idea of immersion the others were exploits of bugs in the physics engine.  



As you can see from the video my victim was in fact suspended by a water bubble for several seconds.  The interesting thing to note is it actually will lift  a character and in some cases it can lift them to a lethal height where upon breaking gravity can be used to smite your enemy.  This sadly was not high enough but the mind bending physics is noticeable.  What happens here is when someone is affected by Bubble Trap is their current forces are nullified; the victim is raised and held for a few seconds then is dropped. No explanation goes into how a fragile bubble can possibly hold a person, it is sorcery after all, so in this case the physics of Archeage is to immerse the player in how it would feel to cast magic.  Also there happen to be a lot of skills in the game that nullify the current forces of the target, some are bugs and others are for effect.

As a whole most video game engines don't take into account every little physical experience that can happen in the real world, just enough to get the job done.  But as we have seen the short-comings of the engine can be intended for immersion to make an imaginary world, or perhaps just make the game more fun even if it’s unintended like with sling-shotting boats into the sky.