### Author Topic: Asteroid collisions  (Read 24675 times)

#### annikk.exe

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##### Asteroid collisions
« on: December 15, 2010, 09:47:12 PM »
Hello,

I'm working on a new level.

It has gravity and Infected AI.
My problem is that I want the asteroids to bounce off each other, instead of passing straight through one another.

This problem is twofold:

1) I need a collision engine to detect when asteroids have collided, and which two asteroids were involved in the collision.
2) Then I need to decide how the asteroids will bounce.  To do that, I need to modify the MomentumX and MomentumY values for those asteroids in a way that is appropriate to the force, relative size, and direction that each roid is travelling in, as well as the angle at which they strike one another.

I am pleased to say that I have part 1 totally sorted.
I use pythagoras to work out the distance between the centres of both asteroids.  Then, if that distance is less than Asteroid 1 Radius + Asteroid 2 Radius, they have collided.
This code works fine.

For part 2, I am struggling.
I am having real difficulty figuring out the formal rules of collision here, and how I express what happens when say, 2 billiard balls collide, in LUA.
I've no clue what sort of equations I should be modelling, or any of the maths that is involved.

Here's a diagram showing the limitations of my current understanding.

For my examples, I assume all objects are of the same size, density, and elasticity/bounciness - though I will also need to gain an understanding of the role these parameters play.

Help with this would be very much appreciated.
« Last Edit: December 15, 2010, 10:08:04 PM by annikk.exe »

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #1 on: December 15, 2010, 11:04:52 PM »
I found some useful equations here.  Hopefully they will work good...

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #2 on: December 16, 2010, 12:04:18 AM »
My notes:

Code: [Select]
`1. Get a normal vector for the 2 colliding roids. nvectorX = CoordX[1] - CoordX[2] nvectorY = CoordY[1] - CoordY[2]2. Next we need a unit vector (or "normalised" vector). That's a vector with a length of 1. To find this, we divide each vector component by the length of the vector. So: unitvectorX = normal vector X / length of normal vector unitvectorY = normal vector Y / length of normal vector uvectorX = nvectorX / math.sqrt((CoordX[1] * CoordX[1]) + (CoordY[2] * CoordY[2])) uvectorY = nvectorY / math.sqrt((CoordX[1] * CoordX[1]) + (CoordY[2] * CoordY[2]))3.  Now we have the Unit Vector, we need the Unit Tangent Vector. utanvectorX = nvectorY * -1 utanvectorY = nvectorX4.  Now we require the speed that each asteroid is travelling. To do this we use Pythagoras triangular shenanigans on the MomentumX and MomentumY values. speed of first asteroid = math.sqrt((MomentumX[1] * MomentumX[1]) + (MomentumY[1] * MomentumY[1])) speed of secnd asteroid = math.sqrt((MomentumX[2] * MomentumX[2]) + (MomentumY[2] * MomentumY[2]))5. Now we need a dot product. To find the dot product of these two vectors: (10,-5) (4,7) We would use this calculation: (10 * 4) + (-5 * 7) = 40 + (-35) = 5 This result is a SCALAR because it expresses an amount only, and not a direction! The calculations we need are: vfirstroidnormal = (unitvectorX * speed of first asteroid) + (unitvectorY * speed of first asteroid) vfirstroidtan    = (utanvectorX * speed of first asteroid) + (utanvectorY * speed of first asteroid) vsecndroidnormal = (unitvectorX * speed of first asteroid) + (unitvectorY * speed of first asteroid) vsecndroidtan    = (utanvectorX * speed of first asteroid) + (utanvectorY * speed of first asteroid)6.  Now we can find the new velocities (as scalars - only speed, no direction specified yet) bouncedvelocity1 = vfirstroidnormal * (roid 1 mass - roid 2 mass) + (2 * roid 2 mass * vsecndroidnormal) / (roid 1 mass + roid 2 mass) bouncedvelocity2 = vsecndroidnormal * (roid 2 mass - roid 1 mass) + (2 * roid 1 mass * vfirstroidnormal) / (roid 1 mass + roid 2 mass) (mass is found by multiplying area by density.  area = pi * radius * radius)7.  `
unfinished..

#### Alex

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##### Re: Asteroid collisions
« Reply #3 on: December 16, 2010, 01:54:05 AM »

#### Pilchard123

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##### Re: Asteroid collisions
« Reply #4 on: December 16, 2010, 03:24:52 AM »

Ok, screeching done. Is this your big bang map? Momentum really gets fun when things join together.

IIRC, it's possible to just deal with the X and Y values for momentum separately, which may make your map easier.

'Kay,

Case 1 - dealt with.
Case 2 - momentum is always conserved, so the total momentum after the collision is 25 + (-75) = -50, so 50 kgm/s to the left.
Case 3 - X : 25 + (-75) = -50, so 50 kgm/s to the left.
Y : (-25) + 75 = 50, so 50 kgm/s to the to.
Case 4 - X : 25 + (-75) = -50, so 50 kgm/s to the left.
Y : 0 + 0 = 0, so as the two bodies have equal masses they must travel vertically at equal and opposite velocities.
« Last Edit: December 16, 2010, 04:45:19 AM by Pilchard123 »

#### Sniped50

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##### Re: Asteroid collisions
« Reply #5 on: December 17, 2010, 05:24:07 AM »
@Pilchard123
Heh heh heh...   Eufloria doesn't use 3D asteroids you know. You're thinking of SPHERES. Eufloria only uses 2D CIRCLES, so annikk got it right the first time. Sorry to rain on your parade, though.

@Annikk.exe
Quick question, are these collisions going to be elastic (i.e. no kinetic energy is lost)? It would not only help to keep the map moving, but it would also stop the asteroids from clumping together in the centre because they lost most of their momentum AND because of gravity.
Just thought I'd mention it. It would be embarassing if you released a beta version of the map and THAT came up!

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##### Re: Asteroid collisions
« Reply #6 on: December 18, 2010, 01:24:05 AM »
It's 2D so the mass is equal to the area * density

Case 4.  Think of two pool balls striking each other in that way, glancing off each other.  Does your conclusion seem logical?  It does not, to me...  if they strike at an angle, they go bouncing off at an angle.

Also yes these are elastic collisions.

#### Pilchard123

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##### Re: Asteroid collisions
« Reply #7 on: December 18, 2010, 01:47:15 AM »
It is logical: the vertical components of the velocities will be equal, so the vertical speeds will be the same. Horizontally, the speeds could be totally different.

More stuff - it is possible to work it all out. Momentum is mass*velocity, kinetic (movement) energy is (mass*velocity*velocity)/2. Both must be conserved.

http://en.wikipedia.org/wiki/Elastic_collision#Two-_and_three-dimensional
« Last Edit: December 18, 2010, 01:57:18 AM by Pilchard123 »

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #8 on: December 18, 2010, 11:16:38 AM »
Maybe it's not so clear from the diagram.  Case 4 differs from the others in that the balls don't strike head on.  Instead, they glance off each other by an unspecified amount.

Have you ever played pool?  Or snooker or something?  If a ball strikes another, but it doesn't hit it dead on, it causes the struck ball to spin off at an angle - and not the same angle as the striking ball was travelling in.  I don't know what the angle is, or what maths governs it..  but it's definitely an angle.

In the diagram in Case 4, after the collision I would expect the ball on the left to end up travelling north-west.  The ball on the right would be travelling south-west, I think.
The fact that they strike each other at an angle - and that they are both round - causes them to have vertical as well as horizontal components to their momentum following the collision.  I am having trouble trying to figure out the maths that governs these angles.

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #9 on: December 18, 2010, 11:29:38 AM »
This diagram from the wikipedia article you linked shows exactly what I mean :>

It also kind of shows me how to work it out, I think...  The article gives the equations for if the second body is at rest, but I think I can see how I would combine it with another momentum vector.. :>

I just got back from an epic journey, though.  Sleep time now.  :>

#### Pilchard123

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##### Re: Asteroid collisions
« Reply #10 on: December 19, 2010, 09:00:24 PM »
Ooh - possible problem.

Your MomentumX and MomentumY - are they the velocities of the roids, or are they really the momentum? Could have a bearing on how you code, etc.

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #11 on: December 19, 2010, 10:59:20 PM »
There are three parameters that pertain to movement: Coord, Momentum and Acceleration:

CoordX[1]
CoordY[1]
MomentumX[1]
MomentumY[1]
AccelerationX[1]
AccelerationY[1]

Coords describe the X and Y position of an asteroid's centre.
Momentum describes how much that asteroid will move (X and Y) in the next cycle of the gravity engine.  Each cycle, the momentum is added (or subtracted) from the Coord, so as to give the new position of the asteroid.
Acceleration describes how much ADDITIONAL momentum will be added or subtracted from the corresponding Momentum value, based on gravity (and any bouncing) during the next cycle of the gravity engine.  Acceleration is zeroed each cycle and recalculated for the new positions and corresponding gravitational influence of all asteroids.

The velocity of an asteroid would be a scalar (magnitude only) obtained by finding the Hypotenuse of the triangle with sides MomentumX and MomentumY for the Adjacent and Opposite, for any given asteroid.  Converting between them shouldn't be a problem..

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #12 on: December 19, 2010, 11:40:40 PM »
Not working :\

Code: [Select]
` -- first up, what's the total mass of these colliding objects? imass = math.pi * roidradius[i] * roidradius[i] jmass = math.pi * roidradius[j] * roidradius[j] totalmass = imass + jmass -- what proportion from 0 to 1 of the mass belongs to i? jprop = imass / jmass -- and what proportion of the mass belongs to j? iprop = jmass / imass -- change the momentums of both roids for the bounce. --Calculate the collision angle (A) by using atan2 applied to the difference of the coordinates of each object (x, y): A = math.atan2((CoordY[i] - CoordY[j]), (CoordX[i] - CoordX[j])) -- calculate the velocity of both roids -- i ivelocity = math.sqrt((MomentumX[i] * MomentumX[i]) + (MomentumY[i] * MomentumY[i])) -- j jvelocity = math.sqrt((MomentumX[j] * MomentumX[j]) + (MomentumY[j] * MomentumY[j])) -- Use the collision angle (A), the ball's initial velocity (u) and ball's initial direction (D) to derive it's x/y velocity in the new rotated coordinate system: Di = math.tan(CoordX[i] / CoordY[i]) Dj = math.tan(CoordX[j] / CoordY[j]) v1x = ivelocity * math.cos(Di - A) v1y = ivelocity * math.sin(Di - A) v2x = jvelocity * math.cos(Dj - A) v2y = jvelocity * math.sin(Dj - A) -- Now that we have the collision aligned along the x-axis, all we have to do is apply the 1D collision equation to vx. We will call the final x-velocities for each ball f1x and f2x: f1x = (v1x * (imass - jmass) + (2 * jmass * v2x)) / totalmass f2x = (v2x * (imass - jmass) + (2 * jmass * v1x)) / totalmass -- Now that we we have the final x and y velocities in the rotated coordinate system, we must convert everything back to a normal Cartesian coordinate system, as follows: v1 = math.sqrt((f1x * f1x) + (v1y * v1y)) v2 = math.sqrt((f2x * f2x) + (v2y * v2y)) D1 = math.atan2(v1y,f1x) + A D2 = math.atan2(v2y,f2x) + A -- Now we have the final angle and momentum as a hypotenuse... we can calculate the opposite and adjacent to obtain new momentumX and momentumY MomentumY[i] = v1 * math.cos(D1) MomentumX[i] = v1 * math.sin(D1) MomentumX[j] = v2 * math.cos(D2) MomentumY[j] = v2 * math.sin(D2)`

« Last Edit: December 19, 2010, 11:48:01 PM by annikk.exe »

#### Widget

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##### Re: Asteroid collisions
« Reply #13 on: December 19, 2010, 11:51:34 PM »
Ack, I wish I could help but I've not used any maths worthy of the name in the last decade. It's a really exciting idea but well over my head.

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #14 on: December 20, 2010, 12:31:32 AM »
Think I've cracked it :>

Here's the code.

Code: [Select]
` -- check if there has been a collision -- if collision = true then comboradius = roidradius[i] + roidradius[j] if collision[i] ~= true then collision[i] = false end if collision[j] ~= true then collision[j] = false end if math.sqrt(((CoordX[j] - CoordX[i])^2 + (CoordY[j] - CoordY[i])^2)) < comboradius then -- a collision has occurred! -- modify momentum for bounce values collision[j] = true collision[i] = true -- first up, what's the total mass of these colliding objects? imass = math.pi * roidradius[i] * roidradius[i] jmass = math.pi * roidradius[j] * roidradius[j] totalmass = imass + jmass -- change the momentums of both roids for the bounce. dx = MomentumX[i] - MomentumX[j] dy = MomentumY[i] - MomentumY[j] collision_angle = math.atan2(dy, dx) magnitude_1 = math.sqrt((MomentumX[i] * MomentumX[i]) + (MomentumY[i] * MomentumY[i])) magnitude_2 = math.sqrt((MomentumX[j] * MomentumX[j]) + (MomentumY[j] * MomentumY[j])) direction_1 = math.atan2(MomentumY[i], MomentumX[i]) direction_2 = math.atan2(MomentumY[j], MomentumX[j]) new_xspeed_1 = magnitude_1 * math.cos(direction_1 - collision_angle) new_yspeed_1 = magnitude_1 * math.sin(direction_1 - collision_angle) new_xspeed_2 = magnitude_2 * math.cos(direction_2 - collision_angle) new_yspeed_2 = magnitude_2 * math.sin(direction_2 - collision_angle) final_xspeed_1 = ((imass - jmass) * new_xspeed_1 + (jmass + jmass) * new_xspeed_2) / totalmass final_xspeed_2 = ((imass + imass) * new_xspeed_1 + (jmass - imass) * new_xspeed_2) / totalmass final_yspeed_1 = new_yspeed_1 final_yspeed_2 = new_yspeed_2 MomentumX[i] = math.cos(collision_angle) * final_xspeed_1 + math.cos(collision_angle + math.pi / 2) * final_yspeed_1 MomentumY[i] = math.sin(collision_angle) * final_xspeed_1 + math.sin(collision_angle + math.pi / 2) * final_yspeed_1 MomentumX[j] = math.cos(collision_angle) * final_xspeed_2 + math.cos(collision_angle + math.pi / 2) * final_yspeed_2 MomentumY[j] = math.sin(collision_angle) * final_xspeed_2 + math.sin(collision_angle + math.pi / 2) * final_yspeed_2 else -- else if there wasn't a collision then -- ..add the appropriate amount of acceleration as normal AccelerationX[i] = AccelerationX[i] + (NormalisedVectorX * Fgx / ((roidradius[i] * roidradius[i]) * math.pi) * density[i]) AccelerationY[i] = AccelerationY[i] + (NormalisedVectorY * Fgy / ((roidradius[i] * roidradius[i]) * math.pi) * density[i]) xdiff = CoordX[i] - CoordX[j] ydiff = CoordY[i] - CoordY[j] NormalisedVectorX = xdiff / vectorlength NormalisedVectorY = ydiff / vectorlength AccelerationX[j] = AccelerationX[j] + (NormalisedVectorX * Fgx / ((roidradius[j] * roidradius[j]) * math.pi) * density[j]) AccelerationY[j] = AccelerationY[j] + (NormalisedVectorY * Fgy / ((roidradius[j] * roidradius[j]) * math.pi) * density[j]) end`

#### Widget

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##### Re: Asteroid collisions
« Reply #15 on: December 20, 2010, 12:45:00 AM »
I hope that's the case, and very well done. This'll be a really exciting mechanic to play with.
I'm always amazed by the ambition of your ideas

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #16 on: December 20, 2010, 12:55:40 AM »
I'm having a problem with asteroids getting stuck inside each other.  I guess I'll figure out something to stop that from happening..

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #17 on: December 20, 2010, 02:31:05 AM »
Ok, they shake themselves free now... But I think ultimately, the reason why they are sometimes getting stuck together instead of bouncing off like they should is because the collision detection doesn't detect perfectly where they would intersect, so they are allowed to overlap... and then with the influence of gravity pulling them together, sometimes the "bounce" doesn't bounce them clear of each other...and they get stuck.  The next cycle sees them overlapping and bounces them again, the opposite way... and they sort of judder about together until eventually wriggling free.

So.

I'm currently bouncing after the asteroids have already overlapped.  What I really need to do is reverse them by just the right amount so that they are _just_ touching, but not overlapping.  I need to move them backward to those positions, then carry out the bounce from there.  :>

Wonder how I do that. :>

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #18 on: December 20, 2010, 05:10:29 AM »
Hmm, I didn't completely solve that problem... but regardless, I now have something approaching a pretty playable level.

Testing it now.  It's fun. :D

#### Sniped50

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##### Re: Asteroid collisions
« Reply #19 on: December 20, 2010, 06:03:30 AM »
Oooh, could we have a play around with it?

For research purposes, you understand...

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #20 on: December 20, 2010, 06:11:25 AM »
After I add victory conditions.  And a screen wrap bounding box.  And maybe a paralax scrolling engine.

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #21 on: December 20, 2010, 09:27:37 PM »
Ok the bounding box is in.  Not sure if I'll bother with a parallax engine for this level, or leave it for the next level.  However, there is a big problem with the AI.  It stops spreading to new asteroids after a while, and just sits there.  I may need to overhaul the AI engine...

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #22 on: December 20, 2010, 11:59:53 PM »
Eh... might as well, I guess.  It's going to take me a while to re-write the Infected AI, so I guess the interested folks can take a look at this in the mean time.
This has Infected AI version 1, which is not very good on dynamic maps like this one.  So it won't be much challenge to beat it, I think.  There also aren't any victory/loss conditions in this.  Very much in development.. :P

Copy and paste this into a LUA file.
Feel free to play around with the code and change stuff or whatever, but please don't release any levels with any of the new functionalities in this, until I've made my own debut.  :>

Code: [Select]
`function LevelSetup() -- ** None of these are strictly necessary for Gravity... change as you like. ** SetBackdropColour(0,0,0) Globals.Agents.MaxSpeed=600 Globals.Agents.MinSpeed=200 Globals.Mines.MinSpeed=1200 Globals.Mines.MaxSpeed=1200 Globals.Mines.MinHealth=2000 Globals.Mines.MaxHealth=2000 Globals.Asteroids.MaxTrees=3 Globals.Asteroids.MinRadius=125    Globals.Asteroids.MaxRadius=725    Globals.Asteroids.RadiusPowerRule=1.5 Globals.Asteroids.MinCoreHealth=50 Globals.Asteroids.MaxCoreHealth=900 Globals.Asteroids.CoreHealthPower=1    Globals.Asteroids.MinSendDistance=60000    Globals.Asteroids.MaxSendDistance=60000    Globals.Asteroids.SendPowerRule=1.4 Globals.Asteroids.SpawnCap=40 Globals.Asteroids.SeedlingCap=1000 Globals.G.Asteroids=(0) Globals.AI.GraceTimer=(9999999) Globals.G.EnemyFactionsMin=(0) Globals.G.EnemyFactionsMax=(0) Globals.G.MinAsteroidSeparation=100 Globals.G.MaxAsteroidNeighbourDist=60000 Globals.G.GreysProbability=0 Globals.Structures.FlowerProbability=(0.1) SetVignetteAlpha(0) -- ** -- ** Initialise Gravity Variables.  No need to change anything here. AccelerationX = {} AccelerationY = {} MomentumX = {} MomentumY = {} density = {} CoordX = {} CoordY = {} roidradius = {} str = {} ene = {} spe = {} collision = {} collisiontimer = {} Timer = 0 collidedbefore = {} oldCoordX = {} oldCoordY = {} -- ** -- ** G is the gravitational constant.  Affects how powerful gravity is in the entire map.  Change this as you like. ** G = 0.01 -- ** -- **************************************** -- **********Asteroid Creation************* -- **************************************** -- -- How To. -- * First we declare the asteroid ID to the Gravity Engine. -- EG: -- roid = 0 -- * Next comes the Acceleration array slot init.  These should always be set to 0. -- EG: -- AccelerationX[roid] = 0 -- AccelerationY[roid] = 0 -- * MomentumX and MomentumY declare the initial velocity of the asteroid. -- EG: -- MomentumX[roid] = 10 -- MomentumY[roid] = 0 -- This example would produce an asteroid that is drifting east when the game begins. -- * Density governs how dense the asteroid is.  An asteroid that was made of metal has a higher density than an asteroid made of gas.  Higher density means stronger gravity per unit of radius. -- EG: -- density[roid] = 1 -- * The coordinates of the asteroid when the game begins. -- EG: -- CoordX[roid] = 12000 -- CoordY[roid] = -8000 -- * Finally, we set the radius of the asteroid.  Bigger asteroids have more gravity, but also weigh more so move in a "heavier" fashion. -- EG: -- roidradius[roid] = 400 -- Now we have declared all necessary gravity variables for the new asteroid, we can create it. -- EG: -- a = AddAsteroidWithAttribs(CoordX[roid],CoordY[roid],0.5,0.5,1) -- a.Owner = 1 -- a.TreeCap = 2 -- a:SetRadius(roidradius[roid]) -- a:Reveal(1) -- a.Moveable = False -- any other commands you would like to run on this asteroid... -- There are 3 different possible gravity behaviours; well-only, and full gravity, and static. -- The asteroids MUST be created in the correct sections. -- Please see below examples of all three different classes of asteroids. -- *** -- 1.  THE BELOW ASTEROIDS HAVE A GRAVITY WELL BUT DO NOT THEMSELVES MOVE -- *** -- Asteroid 0 - A Sun -- gravity variables roid = 0 AccelerationX[roid] = 0 AccelerationY[roid] = 0 MomentumX[roid] = 0 MomentumY[roid] = 0 density[roid] = 10 CoordX[roid] = 0 CoordY[roid] = 0 oldCoordX[roid] = 0 oldCoordY[roid] = 0 roidradius[roid] = 300 -- Creation a = AddAsteroidWithAttribs(CoordX[roid],CoordY[roid],0.5,0.5,1) a.Owner = 1 a.TreeCap = 6 a:SetRadius(roidradius[roid]) a:Reveal(1) a.Moveable = False a:AddSeedlings(60) a:AddDysonTree() -- ** counter for gravity behaviour divisions, do not remove ** wellonlythreshold = roid + 1 -- ** -- *** -- 2.  THE BELOW ASTEROIDS HAVE A GRAVITY WELL, AND MOVE -- *** -- Asteroid 1 - A moving asteroid -- gravity variables name = 0 for setcollide = 0, 25 do collidedbefore[setcollide] = 0 end for makeroids = 1,25 do roid = makeroids AccelerationX[roid] = 0 AccelerationY[roid] = 0 CoordX[roid] = math.random(-15000,15000) CoordY[roid] = math.random(-15000,15000) oldCoordX[roid] = CoordX[roid] oldCoordY[roid] = CoordY[roid] if CoordX[roid] < 0 then MomentumY[roid] = math.random(1,5) else MomentumY[roid] = math.random(-5,1) end if CoordY[roid] < 0 then MomentumX[roid] = math.random(-5,1) else MomentumX[roid] = math.random(1,5) end density[roid] = 1 roidradius[roid] = math.random(110,260) str[roid] = (math.random(1,10) / 10) * (roidradius[roid] / 260) ene[roid] = (math.random(1,10) / 10) * (roidradius[roid] / 260) spe[roid] = (math.random(1,10) / 10) * (roidradius[roid] / 260) -- Creation a = AddAsteroidWithAttribs(CoordX[roid],CoordY[roid],str[roid],ene[roid],spe[roid]) a.Owner = 2 a.TreeCap = 4 a:SetRadius(roidradius[roid]) a:Reveal(1) a.Moveable = False name = name + 1 a.Name = name end GetAsteroid(2):AddSeedlings(250, 2, 0.1, 0.1, 1) -- ** counter for gravity behaviour divisions, do not remove ** gravroidsthreshold = roid -- ** -- 3.  THE BELOW ASTEROIDS DO NOT MOVE AND DO NOT HAVE A GRAVITY WELL -- spacer asteroid, used to make sure the level is big enough for asteroids to wander about on long, eliptical orbits.  Change to taste. a = AddAsteroidWithAttribs(55000,5000,0.5,0.5,0.5) a.Owner = 0 a.TreeCap = 4 a:SetRadius(1) a.Moveable = False roidnumber = roid -- END ASTEROID CREATION -- START AI ENGINE INITIALISATION rcolour = 0 endfinal = false finality = false dangertimer = {} purgetimer = 0 for dset = 0,roidnumber do dangertimer[dset] = GetGameTime() - 90 end danger = {} torchlit = {} constructionmetric = {} gathermetric = {} gatherexists = 0 gatherpoint = GetAsteroid(33) -- END AI ENGINE INITIALISATION timeoff = false endfunction LevelDraw() -- left line Line1x1 = -18000 Line1y1 = -18000 Line1x2 = -18000 Line1y2 = 18000 -- bottom line Line2x1 = -18000 Line2y1 = -18000 Line2x2 = 18000 Line2y2 = -18000 -- right line Line3x1 = 18000 Line3y1 = -18000 Line3x2 = 18000 Line3y2 = 18000 -- top line Line4x1 = -18000 Line4y1 = 18000 Line4x2 = 18000 Line4y2 = 18000 DrawLine(Line1x1,Line1y1,Line1x2,Line1y2,0,0,1,1,0,1,0,1,20) DrawLine(Line2x1,Line2y1,Line2x2,Line2y2,0,0,1,1,0,1,0,1,20) DrawLine(Line3x1,Line3y1,Line3x2,Line3y2,0,0,1,1,0,1,0,1,20) DrawLine(Line4x1,Line4y1,Line4x2,Line4y2,0,0,1,1,0,1,0,1,20) endfunction LevelLogic() -- Zoom the camera SetCameraZoom(9) -- *** Set the send distances you want for each asteroid here. -- *** I know you normally do it in Level Setup but in gravityland we do it here. GetAsteroid(0).SendDistance = 6000 for ii = 1,roidnumber do GetAsteroid(ii).SendDistance = 500 + roidradius[ii] * 10 end -- *** End setting of send distances while GameRunning() do -- *** YOUR LOOPED COMMANDS GO HERE *** -- for wrap = 0,roidnumber do if CoordX[wrap] > 18000 then CoordX[wrap] = -18000 end if CoordY[wrap] > 18000 then CoordY[wrap] = -18000 end if CoordX[wrap] < -18000 then CoordX[wrap] = 18000 end if CoordY[wrap] < -18000 then CoordY[wrap] = 18000 end end -- Make the asteroids appear, one by one... -- for slow = 0,roidnumber do-- if MomentumX[slow] > 15 or MomentumX[slow] < -15 then-- MomentumX[slow] = MomentumX[slow] * 0.98-- end-- if MomentumY[slow] > 15 or MomentumY[slow] < -15 then-- MomentumY[slow] = MomentumY[slow] * 0.98-- end-- end -- *** YOUR LOOPED COMMANDS END HERE *** --- -- START GRAVITY ENGINE -- change things below this line at your own peril!! -- Rate Limiter - necessary to pause gravity simulation if the game is paused. if GetGameTime() > Timer + 0.0 then Timer = GetGameTime() -- Get values for the the array for i = 0, gravroidsthreshold do for j = i + 1, gravroidsthreshold do -- calculate Fgx and Fgy between i and j, then... Fgx = (G * ((roidradius[i] * roidradius[i]) * math.pi * density[i]) * ((roidradius[j] * roidradius[j]) * math.pi * density[j])) / ((CoordX[j] - CoordX[i])^2 + (CoordY[j] - CoordY[i])^2) Fgy = (G * ((roidradius[i] * roidradius[i]) * math.pi * density[i]) * ((roidradius[j] * roidradius[j]) * math.pi * density[j])) / ((CoordX[j] - CoordX[i])^2 + (CoordY[j] - CoordY[i])^2) -- now we have the force of gravity x and y, as a scalar.  we must find the direction to point in: xdiff = CoordX[j] - CoordX[i] ydiff = CoordY[j] - CoordY[i] -- find the length of the vector.. vectorlength = math.sqrt(xdiff^2 + ydiff^2) -- divide the vectors by the length to normalise NormalisedVectorX = xdiff / vectorlength NormalisedVectorY = ydiff / vectorlength -- these normalised vectors are values between 0 and 1 that give us a direction :> -- check if there has been a collision -- if collision = true then comboradius = roidradius[i] + roidradius[j] if collision[i] ~= true then collision[i] = false end if collision[j] ~= true then collision[j] = false end if math.sqrt(((CoordX[j] - CoordX[i])^2 + (CoordY[j] - CoordY[i])^2)) < comboradius then -- a collision has occurred! -- update the positions of the colliding (and overlapping) roids to the positions from the previous cycle (lazy method) -- CoordX[i] = oldCoordX[i] -- CoordY[i] = oldCoordY[i] -- CoordX[j] = oldCoordX[j] -- CoordY[j] = oldCoordY[j] -- modify momentum for bounce values collidedbefore[i] = collidedbefore[i] + 1 collidedbefore[j] = collidedbefore[j] + 1 collision[j] = true collision[i] = true -- first up, what's the total mass of these colliding objects? imass = math.pi * roidradius[i] * roidradius[i] jmass = math.pi * roidradius[j] * roidradius[j] totalmass = imass + jmass -- change the momentums of both roids for the bounce. if collidedbefore[i] < 2 and collidedbefore[j] < 2 then -- These asteroids are not stuck together - bounce them. dx = MomentumX[i] - MomentumX[j] dy = MomentumY[i] - MomentumY[j] collision_angle = math.atan2(dx, dy) magnitude_1 = math.sqrt((MomentumX[i] * MomentumX[i]) + (MomentumY[i] * MomentumY[i])) magnitude_2 = math.sqrt((MomentumX[j] * MomentumX[j]) + (MomentumY[j] * MomentumY[j])) direction_1 = math.atan2(MomentumY[i], MomentumX[i]) direction_2 = math.atan2(MomentumY[j], MomentumX[j]) new_xspeed_1 = 1.05 * magnitude_1 * math.cos(direction_1 - collision_angle) new_yspeed_1 = 1.05 * magnitude_1 * math.sin(direction_1 - collision_angle) new_xspeed_2 = 1.05 * magnitude_2 * math.cos(direction_2 - collision_angle) new_yspeed_2 = 1.05 * magnitude_2 * math.sin(direction_2 - collision_angle) final_xspeed_1 = ((imass - jmass) * new_xspeed_1 + (jmass + jmass) * new_xspeed_2) / totalmass final_xspeed_2 = ((imass + imass) * new_xspeed_1 + (jmass - imass) * new_xspeed_2) / totalmass final_yspeed_1 = new_yspeed_1 final_yspeed_2 = new_yspeed_2 MomentumX[i] = math.cos(collision_angle) * final_xspeed_1 + math.cos(collision_angle + math.pi / 2) * final_yspeed_1 MomentumY[i] = math.sin(collision_angle) * final_xspeed_1 + math.sin(collision_angle + math.pi / 2) * final_yspeed_1 MomentumX[j] = math.cos(collision_angle) * final_xspeed_2 + math.cos(collision_angle + math.pi / 2) * final_yspeed_2 MomentumY[j] = math.sin(collision_angle) * final_xspeed_2 + math.sin(collision_angle + math.pi / 2) * final_yspeed_2 else -- These asteroids are stuck together - don't bounce. end -- ..Now add the appropriate amount of acceleration AccelerationX[i] = AccelerationX[i] + (NormalisedVectorX * Fgx / ((roidradius[i] * roidradius[i]) * math.pi) * density[i]) AccelerationY[i] = AccelerationY[i] + (NormalisedVectorY * Fgy / ((roidradius[i] * roidradius[i]) * math.pi) * density[i]) xdiff = CoordX[i] - CoordX[j] ydiff = CoordY[i] - CoordY[j] NormalisedVectorX = xdiff / vectorlength NormalisedVectorY = ydiff / vectorlength AccelerationX[j] = AccelerationX[j] + (NormalisedVectorX * Fgx / ((roidradius[j] * roidradius[j]) * math.pi) * density[j]) AccelerationY[j] = AccelerationY[j] + (NormalisedVectorY * Fgy / ((roidradius[j] * roidradius[j]) * math.pi) * density[j]) else collidedbefore[i] = 0 collidedbefore[j] = 0 -- else if there wasn't a collision then -- ..add the appropriate amount of acceleration as normal AccelerationX[i] = AccelerationX[i] + (NormalisedVectorX * Fgx / ((roidradius[i] * roidradius[i]) * math.pi) * density[i]) AccelerationY[i] = AccelerationY[i] + (NormalisedVectorY * Fgy / ((roidradius[i] * roidradius[i]) * math.pi) * density[i]) xdiff = CoordX[i] - CoordX[j] ydiff = CoordY[i] - CoordY[j] NormalisedVectorX = xdiff / vectorlength NormalisedVectorY = ydiff / vectorlength AccelerationX[j] = AccelerationX[j] + (NormalisedVectorX * Fgx / ((roidradius[j] * roidradius[j]) * math.pi) * density[j]) AccelerationY[j] = AccelerationY[j] + (NormalisedVectorY * Fgy / ((roidradius[j] * roidradius[j]) * math.pi) * density[j]) end end end for pass = wellonlythreshold,gravroidsthreshold do MomentumX[pass] = MomentumX[pass] + AccelerationX[pass] MomentumY[pass] = MomentumY[pass] + AccelerationY[pass] -- national speed limit if math.sqrt(MomentumX[pass]^2 + MomentumY[pass]^2) > 160 then MomentumX[pass] = MomentumX[pass] * 0.93 MomentumY[pass] = MomentumY[pass] * 0.93 end if math.sqrt(MomentumX[pass]^2 + MomentumY[pass]^2) > 60 then MomentumX[pass] = MomentumX[pass] * 0.98 MomentumY[pass] = MomentumY[pass] * 0.98 end if math.sqrt(MomentumX[pass]^2 + MomentumY[pass]^2) > 10 then MomentumX[pass] = MomentumX[pass] * 0.999 MomentumY[pass] = MomentumY[pass] * 0.999 end -- MOVE GETASTEROID(PASS) by MomentumX and MomentumY if collision[pass] == false then oldCoordX[pass] = CoordX[pass] oldCoordY[pass] = CoordX[pass] end CoordX[pass] = CoordX[pass] + MomentumX[pass] CoordY[pass] = CoordY[pass] + MomentumY[pass] GetAsteroid(pass):MoveTo(CoordX[pass], CoordY[pass]) AccelerationX[pass] = 0 AccelerationY[pass] = 0 end end -- END GRAVITY ENGINE -- *** START INFECTED AI ENGINE *** -- if rcolour > 0 then rcolour = rcolour - 1 end --SetBackdropColour(rcolour,0,0) --AI for check = 0,roidnumber do checkedroid = GetAsteroid(check) if GetGameTime() > purgetimer + 35 then purgetimer = 0 end -- First, find out which asteroids are close enough to travel in 1 jump, and traversable = {} pathsavailable = 0 attackable = {} attackpaths = 0 actiontaken = 0 increasemetricvote = 1 increasegathermetricvote = 1 confirmedzero = 0 confirmedgatherpoint = 0 if GetEmpire(2):OwnsAsteroidID(checkedroid.ID) then -- MINE CHECK NOT REQUIRED IN THIS MAP --if checkedroid:GetNumSeedlings(1) == 0 and checkedroid:GetNumSeedlings(2) > 5 then -- for minecheck = 0,roidnumber do -- if GetEmpire(2):OwnsAsteroidID(minecheck) == true and GetAsteroid(minecheck):GetNumMines(1) > 0 and checkedroid:GetNumMines(1) == 0 then -- checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),GetAsteroid(minecheck)) -- end -- end --end for u = 0,roidnumber do if GetAsteroid(u) ~= checkedroid then -- only learn about this asteroid if it's not the one being checked -- can we send seeds to this roid from the checked one? if (GetAsteroid(checkedroid.ID):GetSendDistance() + roidradius[u]) > math.sqrt(((CoordX[u] - CoordX[checkedroid.ID])^2) + ((CoordY[u] - CoordY[checkedroid.ID])^2)) then -- we can !  Now is this a friendly path or an attackable path? if GetEmpire(2):OwnsAsteroidID(u) == false then attackable[attackpaths] = GetAsteroid(u) attackpaths = attackpaths + 1 -- moar aggression ! advantage pressing, etc if checkedroid:GetNumSeedlings(2) > 120 and GetAsteroid(u):GetNumSeedlings(1) < (checkedroid:GetNumSeedlings(2) / 2) and checkedroid:GetNumSeedlings(1) < 10 then checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),GetAsteroid(u)) if rcolour < 105 then rcolour = rcolour + 150 end end elseif GetAI(2):OwnsAsteroidID(u) == true then traversable[pathsavailable] = GetAsteroid(u) pathsavailable = pathsavailable + 1 if GetAsteroid(u):GetNumTrees() < GetAsteroid(u).TreeCap then constructionmetric[u] = 0 end else end end -- ok, this roid is not in range for us. end -- ok, we were trying to check ourselves. end -- end of neighbour-checking sequence -- end of metric checking sequence else torchlit[checkedroid.ID] = nil constructionmetric[checkedroid.ID] = nil if checkedroid.ID ~= 4 or checkedroid.ID ~= 5 then gathermetric[checkedroid.ID] = nil end end -- we have selected "checkedroid" for checking.  We must find out all we can about the asteroid and it's surroundings, and act appropriately. if GetAI(2):OwnsAsteroidID(checkedroid.ID) == true and checkedroid:GetNumMines(1) > 0 then -- do buggerysquat. elseif GetAI(2):OwnsAsteroidID(checkedroid.ID) == true then -- this roid is ours ! :> -- if pathsavailable == 0 then -- Orphan Control -- boltfriendly = GetEmpire(2):GetRandomAsteroid() -- letsgo = 0 -- for iii = 0,attackpaths do -- if attackable[iii] ~= nil then -- letsgo = letsgo + (attackable[iii]:GetNumSeedlings(1)) -- end -- end -- if letsgo > checkedroid:GetNumSeedlings(2) and checkedroid:GetNumSeedlings(2) > 10 and checkedroid:GetNumSeedlings(2) < 39 then -- checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),boltfriendly) -- elseif letsgo < checkedroid:GetNumSeedlings(2) and checkedroid:GetNumSeedlings(2) > (39 + (attackable[0]:GetNumDysonTrees() * 5) + (attackable[0]:GetNumDefenseTrees() * 15)) then -- checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),attackable[0]) -- if rcolour < 105 then -- rcolour = rcolour + 150 -- end -- elseif attackable[0]:GetNumSeedlings(2) > 5 then -- checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),attackable[0]) -- end -- end -- how many player seedlings are here? -- more than what we have, and enough to be dangerous.  Also, we do have at least 1 tree here, right? if checkedroid:GetNumSeedlings(2) < checkedroid:GetNumSeedlings(1) and checkedroid:GetNumSeedlings(1) > 10 and checkedroid:GetNumTrees() > 0 then -- *** WE OWN THIS ASTEROID, THE ENEMY OUTNUMBER US.  WE HAVE AT LEAST ONE TREE HERE.  We are under attack.  torchmetric 0! *** torchlit[checkedroid.ID] = 0 -- *** -- elseif checkedroid:GetNumSeedlings(2) < checkedroid:GetNumSeedlings(1) and checkedroid:GetNumSeedlings(1) > 10 and checkedroid:GetNumTrees() == 0 then -- *** ITS A FALSE ALARM....but dont try to build here unless the player leaves. *** --torchlit[checkedroid.ID] = nil --constructionmetric[checkedroid.ID] = nil -- but once we get a bit more powerful, we can have a crack at it :> -- if purgetimer == 0 then -- purgetimer = GetGameTime() + 30 -- end -- if GetGameTime() > purgetimer then -- torchlit[checkedroid.ID] = 0 --for purge = 0,roidnumber do -- if GetEmpire(2):OwnsAsteroidID(purge) == true and torchlit[purge] == nil and GetGameTime() > purgetimer + 45 then --GetAsteroid(purge):SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(1),checkedroid) -- if rcolour < 105 then -- rcolour = rcolour + 150 -- end -- end -- end -- purgetimer = 0 -- end -- *** --  more than zero but less than what we have elseif checkedroid:GetNumSeedlings(1) > 0 and checkedroid:GetNumSeedlings(2) > checkedroid:GetNumSeedlings(1) then -- *** WE OWN THIS ASTEROID, THERE ARE ENEMIES BUT WE OUTNUMBER THEM.  Not elligible for sending reinforcements to other asteroids, but not in serious danger either. *** -- *** -- No enemies here at all. elseif checkedroid:GetNumSeedlings(1) < 1 then -- how many of our seedlings are here? if checkedroid:GetNumSeedlings(2) > 1 then -- 1 or more --how many trees are here? if checkedroid:GetNumTrees() < checkedroid.TreeCap and checkedroid:GetNumSeedlings(2) > 9 then -- less than four trees -- *** WE OWN THIS ASTEROID, THERE ARE NO ENEMIES HERE.  WE HAVE AT LEAST 10 SEEDLINGS AND LESS THAN 4 TREES.  Plant a tree. *** -- but... is the enemy building up a force nearby, ready to take our freshly built trees..? danger[checkedroid.ID] = false for ooo = 0,roidnumber do if GetEmpire(1):OwnsAsteroidID(ooo) and GetAsteroid(ooo):GetSendDistance() > math.sqrt(((CoordX[ooo] - CoordX[checkedroid.ID])^2) + ((CoordY[ooo] - CoordY[checkedroid.ID])^2)) then if GetAsteroid(ooo):GetNumSeedlings(1) > 150 then danger[checkedroid.ID] = true dangertimer[checkedroid.ID] = GetGameTime() end end end if danger[checkedroid.ID] == true and checkedroid:GetNumSeedlings(2) > 12 then checkedroid:PlantDysonTree(2) elseif danger[checkedroid.ID] == false and GetGameTime() > dangertimer[checkedroid.ID] + 5 then checkedroid:PlantDysonTree(2) end -- *** elseif checkedroid:GetNumTrees() == checkedroid.TreeCap then -- max trees.  ELLIGIBLE FOR SENDING REINFORCEMENTS! if constructionmetric[checkedroid.ID] == 0 then -- we just built the last tree.  now we should stop advertising to neighbours that we need more seedlings for construction. constructionmetric[checkedroid.ID] = nil end -- is my torch metric nil? if torchlit[checkedroid.ID] ~= nil then -- no, my torch metric is not Nil. -- is my torch metric 0?  Cause, like, I don't have any enemies orbiting me dudez... if torchlit[checkedroid.ID] == 0 then -- *** ok, so my torch metric is 0 but there are no enemies here.  Switch all torches off....if other roids are under attack they will just switch theirs on again straight away. *** -- *** this step is needed to prevent the rest of the torch metrics from spiralling upward out of control.  *** for g = 0,roidnumber do torchlit[g] = nil end -- *** else -- so my torch IS lit, but it's value is NOT zero.  checkedroid is not nil and not 0. totm = true for ooo = 0,pathsavailable do if traversable[ooo] ~= nil then trav = traversable[ooo] hopIDint = trav.ID if torchlit[hopIDint] == 0 and GetGameTime() < 180 then for emerg = 0,roidnumber do if GetEmpire(2):OwnsAsteroidID(emerg) == true then GetAsteroid(emerg):SendSeedlingsToTarget(2,GetAsteroid(emerg):GetNumSeedlings(2),traversable[ooo]) end end totm = false elseif torchlit[hopIDint] == 0 then -- *** WE HAVE FOUND A NEIGHBOUR THAT HAS A ROUTE TO AN ASTEROID IN NEED OF DEFENCE.  Send seedlings *** if GetAsteroid(hopIDint):GetNumSeedlings(1) < 10 then checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),traversable[ooo]) elseif GetAsteroid(hopIDint):GetNumSeedlings(2) > GetAsteroid(hopIDint):GetNumSeedlings(1) * 0.6 then checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),traversable[ooo]) elseif checkedroid:GetNumSeedlings(2) > (GetEmpire(2).NumSeedlings / 20) then checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),traversable[ooo]) end totm = false torchlit[checkedroid.ID] = 1 -- elseif torchlit[checkedroid.ID] == nil then -- totm = false -- torchlit[checkedroid.ID] = torchlit[hopIDint] + 1 -- shortestpath = hopIDint elseif torchlit[hopIDint] == nil then -- do nothing, maybe there's no more attack and the metric should be turned off. -- my torch metric is already non-nil, so set mine to be his + 1 if he has a shorter path than me. elseif torchlit[hopIDint] < torchlit[checkedroid.ID] - 1 then totm = false torchlit[checkedroid.ID] = torchlit[hopIDint] + 1 shortestpath = hopIDint checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),traversable[ooo]) elseif torchlit[hopIDint] == torchlit[checkedroid.ID] - 1 then totm = false torchlit[checkedroid.ID] = torchlit[hopIDint] + 1 shortestpath = hopIDint checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),traversable[ooo]) end end end -- *** WE OWN THIS ASTEROID.  THERE ARE NO ENEMIES HERE.  WE HAVE AT LEAST 10 SEEDLINGS AND MAXIMUM TREES.  OUR TORCH METRIC INDICATES *** -- *** THAT A NEARBY ASTEROID REQUIRES SEEDLINGS FOR DEFENSE.  Find a neighbour with the lower metric and send 10 seedlings there.  *** end elseif torchlit[checkedroid.ID] == nil then -- yes my torch metric is nil, now lets see if any neighbours have a torch metric of 0.. totm = true for ooo = 0,pathsavailable do if traversable[ooo] ~= nil then trav = traversable[ooo] hopIDint = trav.ID if torchlit[hopIDint] == 0 then -- *** WE HAVE FOUND A NEIGHBOUR THAT NEEDS MORE SEEDS TO DEFEND WITH.  Send 10 seedlings, or more if we have them available. *** checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ooo]) totm = false torchlit[checkedroid.ID] = 1 elseif torchlit[hopIDint] ~= nil then if torchlit[hopIDint] > 0 then -- seedlings needed in this direction! -- my torch metric is nil at the moment, so set it to his + 1. if torchlit[checkedroid.ID] == nil then totm = false torchlit[checkedroid.ID] = torchlit[hopIDint] + 1 shortestpath = hopIDint end -- my torch metric is already non-nil, so set mine to be his + 1 if he has a shorter path than me. if torchlit[hopIDint] < torchlit[checkedroid.ID] - 1 then totm = false torchlit[checkedroid.ID] = torchlit[hopIDint] + 1 shortestpath = hopIDint end end end end end -- send seeds along the shortest torch path if torchlit[checkedroid.ID] ~= nil then if torchlit[checkedroid.ID] > 1 then checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),GetAsteroid(shortestpath)) end end if totm == true and torchlit[checkedroid.ID] ~= nil then torchlit[checkedroid.ID] = nil end -- check if we are still under attack on any asteroids stillattacked = false for o = 0,roidnumber do if GetAsteroid(o):GetNumTrees() > 0 and GetAI(2):OwnsAsteroidID(o) and GetAsteroid(o):GetNumSeedlings(1) > 1 then stillattacked = true end end if stillattacked == false then for l = 0,roidnumber do torchlit[l] = nil end end -- yes, my torch metric is Nil and so is all my neighbours' - check my construction metric next. -- turn off construction metric tocm = true for cc = 0,pathsavailable do if traversable[cc] ~= nil then trav = traversable[cc] hopIDint = trav.ID if constructionmetric[hopIDint] == 0 and GetAsteroid(hopIDint):GetNumSeedlings(1) < 8 then -- *** WE HAVE FOUND A NEIGHBOUR THAT NEEDS MORE SEEDS TO BUILD WITH.  Send 10 seedlings, or more if we have them available. *** checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[cc]) tocm = false constructionmetric[checkedroid.ID] = 1 elseif danger[checkedroid.ID] == true or GetGameTime() < (dangertimer[checkedroid.ID] + 90) then -- *** WAIT A BIT... THERE'S STILL A BIG FORCE NEARBY *** tocm = false constructionmetric[checkedroid.ID] = 1 elseif constructionmetric[hopIDint] ~= nil then if constructionmetric[hopIDint] >= 0 then -- seedlings needed in this direction! -- my construction metric is nil at the moment, so set it to his + 1. if constructionmetric[checkedroid.ID] == nil then tocm = false constructionmetric[checkedroid.ID] = constructionmetric[hopIDint] + 1 shortestpath = hopIDint end -- my construction metric is already non-nil, so set mine to be his + 1 if he has a shorter path than me. if constructionmetric[hopIDint] < constructionmetric[checkedroid.ID] - 1 then tocm = false constructionmetric[checkedroid.ID] = constructionmetric[hopIDint] + 1 shortestpath = hopIDint end end end end end -- send seeds along the shortest construction path if constructionmetric[checkedroid.ID] ~= nil then if constructionmetric[checkedroid.ID] > 1 then checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),GetAsteroid(shortestpath)) end end if tocm == true and constructionmetric[checkedroid.ID] ~= nil then constructionmetric[checkedroid.ID] = nil end -- check if we are finished building trees on all asteroids stillbuilding = false for o = 0,roidnumber do if GetAsteroid(o):GetNumTrees() < GetAsteroid(o).TreeCap and GetAI(2):OwnsAsteroidID(o) then stillbuilding = true end end if stillbuilding == false then for l = 0,roidnumber do constructionmetric[l] = nil end end end -- ok, we didn't hit on torch metric or construction metric.  So lets do some gathering instead. if torchlit[checkedroid.ID] == nil and constructionmetric[checkedroid.ID] == nil and GetGameTime() > 6 then -- is there already a gather point? -- gatherexists = 0 gathertrue = false for h = 0,roidnumber do if gathermetric[h] == 0 then gatherexists = 1 gathertrue = true end end if gathertrue == false then gatherexists = 0 end -- there's no gather point at the moment. if gatherexists == 0 then -- ok, is there at least one player-owned asteroid and one traversable asteroid within my send distance? if pathsavailable > 0 and attackpaths > 0 then -- yep. -- *** THEN I'M THE NEW GATHER POINT!! Bringin all the seedlings to the yard, y0. *** gathermetric[checkedroid.ID] = 0 gatherexists = 1 -- MessageBox("new gather point") --MessageBox(checkedroid.ID) else -- nope. -- *** I CAN'T BE THE GATHER POINT because I am totally surrounded by either all friendly neighbours or all enemy asteroids. *** end if gathermetric[checkedroid.ID] ~= nil then -- no, my gather metric is not Nil. -- so my torch IS lit, but it's value is NOT zero. for ddd = 0,pathsavailable do if traversable[ddd] ~= nil then trav = traversable[ddd] hopIDint = trav.ID if gathermetric[hopIDint] == 0 then -- *** WE HAVE FOUND A NEIGHBOUR THAT HAS A ROUTE TO AN ASTEROID IN NEED OF SEEDS.  Send 10 seedlings, or more if we have them available. *** checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ddd]) gathermetric[checkedroid.ID] = 1 electiontimer = GetGameTime() elseif gathermetric[hopIDint] ~= nil then if gathermetric[hopIDint] > 0 then -- both checkedroid and the neighbour we are looking at have a gather metric set.  Also, the neighbour has a metric of at least 1. -- seedlings needed in this direction! -- my gather metric is already non-nil, so set mine to be his + 1 if he has a shorter path than me. if gathermetric[hopIDint] < gathermetric[checkedroid.ID] - 1 then gathermetric[checkedroid.ID] = gathermetric[hopIDint] + 1 shortestpath = hopIDint elseif gathermetric[hopIDint] == gathermetric[checkedroid.ID] - 1 then if shortestpath == nil then shortestpath = hopIDint end if gathermetric[shortestpath] ~= nil then if gathermetric[hopIDint] < gathermetric[shortestpath] then shortestpath = hopIDint end end end end end end end if gathermetric[checkedroid.ID] ~= nil and gathermetric[shortestpath] ~= nil then if gathermetric[shortestpath] < gathermetric[checkedroid.ID] then checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),GetAsteroid(shortestpath)) end end -- *** WE OWN THIS ASTEROID.  THERE ARE NO ENEMIES HERE.  WE HAVE AT LEAST 10 SEEDLINGS AND MAXIMUM TREES.  OUR TORCH METRIC INDICATES *** -- *** THAT A NEARBY ASTEROID REQUIRES SEEDLINGS FOR DEFENSE.  Find a neighbour with the lower metric and send 10 seedlings there.  *** elseif gathermetric[checkedroid.ID] == nil then -- yes my gather metric is nil, now lets see if any neighbours have a gather metric of 0.. for ddd = 0,pathsavailable do if traversable[ddd] ~= nil then trav = traversable[ddd] hopIDint = trav.ID if gathermetric[hopIDint] == 0 then -- *** WE HAVE FOUND A NEIGHBOUR THAT IS A GATHER POINT.  Send 10 seedlings, or more if we have them available. *** checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ddd]) gathermetric[checkedroid.ID] = 1 elseif gathermetric[hopIDint] ~= nil then if gathermetric[hopIDint] > 0 then -- seedlings needed in this direction! -- my gather metric is nil at the moment, so set it to his + 1. if shortestpath == nil then shortestpath = hopIDint end gathermetric[checkedroid.ID] = gathermetric[hopIDint] + 1 end end end end end -- a gather point already exists. else -- Am I the gather point? if gathermetric[checkedroid.ID] == 0 then -- I AM the gather point! :> -- is there still at least 1 player asteroid and 1 friendly asteroid nearby? --validpath = 0 --validattack = 0 --for i = 0,pathsavailable do -- if traversable[i] ~= nil then -- travv = traversable[i] -- travvy = travv.ID -- if GetAI(2):OwnsAsteroidID(travvy) == true then -- there's at least one friendly asteroid nearby. -- validpath = 1 -- end -- if GetAI(2):OwnsAsteroidID(travvy) == false then -- there's at least one player asteroid nearby. -- validattack = 1 -- end -- end --end if attackpaths > 0 and pathsavailable > 0 then -- yes, there's at least 1 friendly and 1 enemy asteroid nearby. -- add up all the player seedlings in the nearby enemy systems.  Do I have at least that, plus 50? totalseeds = 50 currentlowest = 9000 attackpaths = attackpaths - 1 for j = 0,attackpaths do totalseeds = totalseeds + attackable[j]:GetNumSeedlings(1) -- this bit checks which of the asteroids has the lowest number of seedlings. if attackable[j]:GetNumSeedlings(1) < currentlowest then currentlowest = attackable[j]:GetNumSeedlings(1) RAPETARGET = attackable[j] end end -- "if i have more seeds than the enemy does, then..." if checkedroid:GetNumSeedlings(2) > totalseeds + (RAPETARGET:GetNumDysonTrees() * 5) + (RAPETARGET:GetNumDefenseTrees() * 23) then if checkedroid:GetNumSeedlings(1) < 15 then checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),RAPETARGET) if rcolour < 105 then rcolour = rcolour + 150 end end --MessageBox("Rape time!") -- *** RAEP TIEM!!!"!" elseif checkedroid:GetNumSeedlings(2) > 1000 and checkedroid:GetNumSeedlings(1) == 0 then -- if i have silly numbers of seeds, just gogo anyway. if checkedroid:GetNumSeedlings(1) < 15 then checkedroid:SendSeedlingsToTarget(2,checkedroid:GetNumSeedlings(2),RAPETARGET) if rcolour < 105 then rcolour = rcolour + 150 end end else -- *** Hold, precious... we have not enough seeds yet to launch an attack... *** -- *** end -- this bit checks if we have a "Cold War" situation on our hands - if so, we'd be better off moving to a different gather point with less player defenses nearby. -- if totalseeds > 300 and totalseeds > checkedroid:GetNumSeedlings(2) and GetEmpire(1):GetNumOwnedAsteroids() > attackpaths + 1 then -- MessageBox("ColdWar Detected - reset gather point") -- for gathreset = 0,roidnumber do -- gathermetric[gathreset] = nil -- end -- gatherexists = 0 -- end else -- *** I AM NO LONGER A SUITABLE GATHER POINT.  RESET ALL GATHER POINTS for r = 6,roidnumber do gathermetric[r] = nil end gatherexists = 0 -- *** end else -- I am not the gather point. :< -- so send some seedlings to whichever traversable asteroid has the lowest gather metric. -- ADD SOEM CODE HERE DRUIDS if gathermetric[checkedroid.ID] ~= nil then -- no, my gather metric is not Nil. -- so my torch IS lit, but it's value is NOT zero. for ddd = 0,pathsavailable do if traversable[ddd] ~= nil then trav = traversable[ddd] hopIDint = trav.ID if gathermetric[hopIDint] == 0 then -- *** WE HAVE FOUND A NEIGHBOUR THAT HAS A ROUTE TO AN ASTEROID IN NEED OF SEEDS.  Send 10 seedlings, or more if we have them available. *** checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ddd]) gathermetric[checkedroid.ID] = 1 electiontimer = GetGameTime() elseif gathermetric[hopIDint] ~= nil then if gathermetric[hopIDint] > 0 then -- both checkedroid and the neighbour we are looking at have a gather metric set.  Also, the neighbour has a metric of at least 1. -- seedlings needed in this direction! -- my gather metric is already non-nil, so set mine to be his + 1 if he has a shorter path than me. if gathermetric[hopIDint] < gathermetric[checkedroid.ID] - 1 then gathermetric[checkedroid.ID] = gathermetric[hopIDint] + 1 shortestpath = hopIDint checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ddd]) elseif gathermetric[hopIDint] == gathermetric[checkedroid.ID] - 1 then if shortestpath == nil then shortestpath = hopIDint end if gathermetric[shortestpath] ~= nil then if gathermetric[hopIDint] < gathermetric[shortestpath] then shortestpath = hopIDint end end checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ddd]) end end end end end checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),GetAsteroid(shortestpath)) -- *** WE OWN THIS ASTEROID.  THERE ARE NO ENEMIES HERE.  WE HAVE AT LEAST 10 SEEDLINGS AND MAXIMUM TREES.  OUR TORCH METRIC INDICATES *** -- *** THAT A NEARBY ASTEROID REQUIRES SEEDLINGS FOR DEFENSE.  Find a neighbour with the lower metric and send 10 seedlings there.  *** elseif gathermetric[checkedroid.ID] == nil then -- yes my gather metric is nil, now lets see if any neighbours have a gather metric of 0.. for ddd = 0,pathsavailable do if traversable[ddd] ~= nil then trav = traversable[ddd] hopIDint = trav.ID if gathermetric[hopIDint] == 0 then -- *** WE HAVE FOUND A NEIGHBOUR THAT IS A GATHER POINT.  Send 10 seedlings, or more if we have them available. *** checkedroid:SendSeedlingsToTarget(2,((checkedroid:GetNumSeedlings(2)/pathsavailable) + 10),traversable[ddd]) gathermetric[checkedroid.ID] = 1 elseif gathermetric[hopIDint] ~= nil then if gathermetric[hopIDint] > 0 then -- seedlings needed in this direction! -- my gather metric is nil at the moment, so set it to his + 1. if shortestpath == nil then shortestpath = hopIDint end gathermetric[checkedroid.ID] = gathermetric[hopIDint] + 1 end end end end end end end end end end -- how many of our seedlings are here? if checkedroid:GetNumSeedlings(2) < 10 then -- 9 or less -- how many trees are here? if checkedroid:GetNumTrees() < checkedroid.TreeCap then -- less than four trees -- *** WE OWN THIS ASTEROID, THERE ARE NO ENEMIES HERE.  WE HAVE LESS THAN 10 SEEDLINGS AND LESS THAN 4 TREES.  We need seedlings for more trees!  Advertise to neighbours that we need some. constructionmetric[checkedroid.ID] = 0 -- *** end end end else -- *** THIS ROID IS NOT OURS, it's a PLAYER asteroid!!  Do nothing with it.  :> *** -- *** end if GetEmpire(1):GetNumOwnedAsteroids() < 4 and GetEmpire(2).NumSeedlings > 800 and finality == false then finality = true for doom = 0,roidnumber do if GetEmpire(2):OwnsAsteroidID(doom) then GetAsteroid(doom):SendSeedlingsToTarget(2,GetAsteroid(doom):GetNumSeedlings(2),GetEmpire(1):GetRandomAsteroid()) end end end if electiontimer ~= nil then if GetGameTime() > electiontimer + 45 then -- we haven't managed to send any seedlings to a gather point for 45 seconds now.  Lets try resetting all the gather metrics to trigger a new gather point election. for greset = 6,roidnumber do gathermetric[greset] = nil end --MessageBox("Due to low activity a new gather point election was held") -- lets see if this helps, and seeds now start moving towards the gather point.  if it doesn't, hold a new gather point election in 15 seconds. electiontimer = electiontimer + 45 gatherexists = 0 end end gatherzero = false for gatherzerocheck = 0,roidnumber do if gathermetric[gatherzerocheck] == 0 then gatherzero = true end end if gatherzero == false then gatherexists = 0 end if GetEmpire(2).NumSeedlings > 8000 and GetEmpire(2):GetNumOwnedAsteroids() > roidnumber / 2 and endfinal == false then endfinal = true for final = 0,roidnumber do if GetEmpire(2):OwnsAsteroidID(final) then GetAsteroid(final):SendSeedlingsToTarget(2,GetAsteroid(final):GetNumSeedlings(2),GetEmpire(1):GetRandomAsteroid()) end end end end -- *** END INFECTED AI ENGINE *** -- coroutine.yield() endend`

#### Sniped50

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##### Re: Asteroid collisions
« Reply #23 on: December 21, 2010, 07:36:56 AM »
I've had a look. It doesn't look finished but...

DAMN. IT LOOKS FRICKING AWESOME!
Can't wait to see what it'd be like when it IS finished! The bounding box is also a nice touch...

I can't believe you managed to (sort of) get it working! Thank you!

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #24 on: December 21, 2010, 08:13:35 AM »
Glad you like it.  :> Wait till you see the other stuff I'm working on!

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #25 on: December 23, 2010, 12:53:19 AM »
I've tried putting the Infected AI v2 engine into this map, and it works a treat.  :>
There is one minor bug with the AI behaviour so far, but the performance is miles better than v1.

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #26 on: January 01, 2011, 02:48:16 PM »
I'm currently bouncing after the asteroids have already overlapped.  What I really need to do is reverse them by just the right amount so that they are _just_ touching, but not overlapping.  I need to move them backward to those positions, then carry out the bounce from there.  :>

Wonder how I do that. :>

I had a brainwave tonight (er, this morning..) and figured out how to do his.

Some preparation was necessary.  At various points I had to record the existing momentums and coords for both roids, so that they can be restored following a modification.

Here's an explanation of how I did it:

1.  Basically I realised I needed to find two values: The amount the asteroids moved in the latest frame which resulted in a collision, and the amount by which this movement caused them to overlap with each other.

2.  Dividing the latter by the former always gives you a value between 0 and 1, which I have decided to refer to as the ratio of overlap.  This ratio is crucial to the calculations that follow.

3.  So next, I move the asteroid back to where it was the previous frame, recording the current momentums.

4.  Then I move both asteroids forward by momentum * (1 - ratio of overlap), and this brings them to the _exact_ point where the two asteroids touch.

5.  I restore the original momentum values from step 3 in preparation for the bounce.

6.  The bounce calculation is carried out - and it is an "ideal bounce".  The bounce results in new momentum values for both asteroids.

7.  The new momentums are saved.

8.  The momentum is then multiplied by the ratio of overlap.  This gives the remainder of the movement that occurs for this frame, _after_ the "ideal bounce".

9.  Then the asteroids are moved forward in the resultant new direction by whatever amount of ratio * momentum is leftover after the bounce.

10. Then the saved momentums from step 7 are restored.

At this point, the perfect bounce is complete and normal acceleration/movement/gravity calculations can continue.

This was not simple.  :>  But it looks excellent...  Moving asteroids do not get stuck inside each other anymore.  They bounce perfectly every time.

However, this has introduced a new problem.  Due to the screen wrapping, eventually all the asteroids clump up together in the middle!  This is not an incorrect result though - they would naturally do that.  The behaviour simply falls out of the equations naturally.
I will try experimenting to make the asteroids bounce away from each other with more force than they collided with.  Maybe that will prevent the clumping behaviour.
« Last Edit: January 01, 2011, 02:55:16 PM by annikk.exe »

#### pigpenguin

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##### Re: Asteroid collisions
« Reply #27 on: January 01, 2011, 05:02:09 PM »
So lets see here that is 3 new mechanics you managed to add to a game with using only scripts in the map editor they got their modding better then most games do. They also have some very creative smart people working on it. Its way over my head atm so I just came to compliment

#### annikk.exe

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##### Re: Asteroid collisions
« Reply #28 on: January 01, 2011, 09:03:07 PM »
Yep, it's pretty damn powerful :>  That's why I enjoy it so much...the massive creative freedom..
One of the main reasons I've been able to do all this, though, is because of the sympathetic ears of Alex and Rudolf who have actually added scripting commands by request - which is an amazing thing.  For example it didn't used to be possible to move asteroids, but now thanks to their support that is possible.  A gravity engine would have been out of the question had it not been for their kindly intervention.  :>  I think it's important to remember that the game would not exist in the first place without them.

It's hugely satisfying when you get a new mechanic working.  I'm going to release a new level soon, which will include the gravity engine with ideal bounce, parallax scrolling, and AIv2.  That's enough new features to justify a new Annikk map, I think. :>

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