public static decimal forceBetweenParticles(particle acting, particle actedUpon)
{
var posDiff = actedUpon.position - acting.position;
decimal dist = posDiff.magnitude * scale;
if (dist == 0)
{
dist = 0.000000001M;
}
return((k * acting.charge * q * actedUpon.charge * q) / (dist * dist));
}
public simulationCell(simPoint tlBoundary, simPoint brBoundary, List <simPoint> geometry, int numberOfParticles, particle prototype, vector startingVector = null)
{
topLeftBoundary = tlBoundary;
bottomRightBoundary = brBoundary;
containedGeometry = geometry;
initialPrototype = prototype;
initialVectorPrototype = startingVector;
spawnParticles(numberOfParticles, prototype, startingVector);
}
private void spawnParticles(int particles, particle proto, vector v)
{
var height = bottomRightBoundary.y - topLeftBoundary.y;
var width = bottomRightBoundary.x - topLeftBoundary.x;
if (height == 0 || width == 0)
{
throw new Exception("Can't define simulation zone with zero area!");
}
decimal ratio = height / width;
decimal inverseRatio = 1 / ratio;
decimal numberToMultiply = vector.Sqrt(particles);
int wide = (int)(inverseRatio * numberToMultiply);
int high = (int)(ratio * numberToMultiply);
if (containedParticles == null)
{
containedParticles = new List <particle>();
}
for (int x = 0; x < wide; x++)
{
for (int y = 0; y < high; y++)
{
particle p = proto.copyWithNewID;
decimal posx = topLeftBoundary.x + (width / wide) * x;
decimal posy = topLeftBoundary.y + (height / high) * y;
p.position = new simPoint(posx, posy);
if (v != null)
{
p.momentum = v;
}
containedParticles.Add(p);
}
}
}
//air will always flow right to left
public simulation(List <simPoint> geometryPoints, int width = 700, int height = 300, int cellsHigh = 6, int cellsWide = 16, decimal baseDensity = 0.0125M, vector startingVelocity = null, particle p = null)
{
spawnCells = new List <simulationCell>();
int realWidth = width * 2;
int realCellsWide = cellsWide + 2;//* 2;
if (startingVelocity == null)
{
startingVelocity = new vector(-0.1M, 0);
}
if (p == null)
{
p = new particle()
{
momentum = startingVelocity, repellanceCoefficient = airCoefficient, position = vector.zero.asPoint
}
}
;
if (cells == null)
{
cells = new List <simulationCell>();
}
decimal cellWidth = (decimal)(width / cellsWide);
decimal cellHeight = (decimal)(height / cellsHigh);
int particlesPerCell = (int)(cellWidth * cellHeight * baseDensity);
spawncount = particlesPerCell;
Dictionary <Tuple <int, int>, simulationCell> cellDict = new Dictionary <Tuple <int, int>, simulationCell>();
for (int x = -1; x <= realCellsWide; x++)
{
for (int y = -1; y <= cellsHigh; y++)
{
simPoint topLeftB = new simPoint(x * cellWidth, y * cellHeight);
simPoint bottomRightB = new simPoint((x + 1) * cellWidth, (y + 1) * cellHeight);
//make real simulation cells
simulationCell c;
if (y >= 0 && y < cellsHigh)
{
if (x > cellsWide && x < realCellsWide)
{
c = new simulationCell(topLeftB, bottomRightB, new List <simPoint>(), particlesPerCell, p);
spawnCells.Add(c);
}
else if (x >= 0)
{
List <simPoint> ptsRelevant = geometryPoints.FindAll((s) => {
if (s.x <= bottomRightB.x && s.x >= topLeftB.x && s.y >= topLeftB.y && s.y < bottomRightB.y)
{
return(true);
}
else
{
return(false);
}
});
c = new simulationCell(topLeftB, bottomRightB, ptsRelevant, 0, p);
}
else
{
c = new simulationCell(particlesPerCell / 2, topLeftB, bottomRightB);
}
}
else
{
c = new simulationCell(particlesPerCell / 2, topLeftB, bottomRightB);
}
cellDict[new Tuple <int, int>(x, y)] = c;
cells.Add(c);
}
}
for (int x = 0; x < realCellsWide; x++)
{
for (int y = 0; y < cellsHigh; y++)
{
cellDict[new Tuple <int, int>(x, y)].bottom = cellDict[new Tuple <int, int>(x, y + 1)];
cellDict[new Tuple <int, int>(x, y)].top = cellDict[new Tuple <int, int>(x, y - 1)];
cellDict[new Tuple <int, int>(x, y)].right = cellDict[new Tuple <int, int>(x + 1, y)];
cellDict[new Tuple <int, int>(x, y)].left = cellDict[new Tuple <int, int>(x - 1, y)];
cellDict[new Tuple <int, int>(x, y)].bottomRight = cellDict[new Tuple <int, int>(x + 1, y + 1)];
cellDict[new Tuple <int, int>(x, y)].bottomLeft = cellDict[new Tuple <int, int>(x - 1, y + 1)];
cellDict[new Tuple <int, int>(x, y)].topRight = cellDict[new Tuple <int, int>(x + 1, y - 1)];
cellDict[new Tuple <int, int>(x, y)].topLeft = cellDict[new Tuple <int, int>(x - 1, y - 1)];
}
}
}
