There is an issue with detecting collision on the bodies travailing very fast.In a regular way it may occur that at the next collision test the object (bullet ) is already past the collision point. For this CCD is the solution .Ray is a simplest solution however. You cast it in the direction of the bullet path.You get the hit ( the distance to the collision point) .Assuming that the travel time is CONSTANT ray model works fine .Because in this case you get the exact time of the hit and have an ability to predict the impact.If the speed is changing or the impacted object is dynamic you should better got CCD solution.It really depends on if you want to have a physical behavior of the projectile becasue in this vase you should take into account (acceleration,gravity ,drag forces etc) or just a simple bullet constant speed model which would be pretty easy to simulate."Physics for Game Programers" book is very nice resource to learn this stuff.
On Thu, Mar 17, 2011 at 3:34 PM, Arkadianen <[email protected]> wrote: > How CCD differs from collision iteration? > Can we calculate collisions in GPU ? What other operations can be made > in GPU? > > > On Mar 16, 10:05 pm, Michael Iv <[email protected]> wrote: > > Usually in fps shooters ray is used to get hit position . Another method > for bullets hit test is CCD ( continuous collision detection ) . It can be > used with rays or on it's own . Google for the exact implementation . If I > recall right Seb Lee had an example on his blog . Also check JigLib may be > it has got built in CCD > > > > Sent from my iPhone > > > > On Mar 16, 2011, at 9:02 PM, pokey <[email protected]> wrote: > > > > > > > > > Hi there, > > > > > I'm new to Away3D, and trying to create an oh so simple little > > > shooting gallery: it will have a plane with some cubes scattered on > > > it, and you will use the mouse as a crosshair to fire projectiles at > > > the cubes, from a vantage point hovering over the plane. > > > > > My hangup is getting the projectile firing, and testing whether it > > > hits a target (the cubes, or the plane itself). I'll have some > > > function defining the position of the projectiles as a function of > > > time and where the crosshairs were aimed when they were released. At > > > this point, I could just have iterate through every cube (and the > > > plane) at each frame testing if one of the projectiles has collided > > > with it. I'm wondering if anyone could suggest a simpler way to > > > proceed utilizing some Away3D libraries? The getIntersect() method in > > > Ray.as looks promising, though it's not completely clear to me what > > > this does (nor can I find much documentation). > > > > > Cheers, > > > P > -- Michael Ivanov ,Programmer Neurotech Solutions Ltd. Flex|Air |3D|Unity| www.neurotechresearch.com http://blog.alladvanced.net Tel:054-4962254 [email protected] [email protected]
