// Returns starting position for a body in simulation space coordinates
public SimPoint GetStartingPosition(GravitySim.BodyStartPosition startPos)
{
const double stagePosition = 0.5; // For the "stage" positions - proportion of the way from the center of the stage to the edge
// in all directions
double simBoxMaxXY = simSpace.SimBoxHeightAndWidth / 2.0;
double stageXY = simBoxMaxXY * stagePosition;
double screenMaxX = screenSimulationDimensions.X / 2.0;
double screenMaxY = screenSimulationDimensions.Y / 2.0;
switch (startPos)
{
case GravitySim.BodyStartPosition.StageLeft:
return(new SimPoint(-stageXY, 0.0));
case GravitySim.BodyStartPosition.StageRight:
return(new SimPoint(stageXY, 0.0));
case GravitySim.BodyStartPosition.StageTop:
return(new SimPoint(0.0, stageXY));
case GravitySim.BodyStartPosition.StageBottom:
return(new SimPoint(0.0, -stageXY));
case GravitySim.BodyStartPosition.StageTopLeft:
return(new SimPoint(-stageXY, stageXY));
case GravitySim.BodyStartPosition.StageTopRight:
return(new SimPoint(stageXY, stageXY));
case GravitySim.BodyStartPosition.StageBottomLeft:
return(new SimPoint(-stageXY, -stageXY));
case GravitySim.BodyStartPosition.StageBottomRight:
return(new SimPoint(stageXY, -stageXY));
case GravitySim.BodyStartPosition.ScreenLeft:
return(new SimPoint(-screenMaxX, 0.0));
case GravitySim.BodyStartPosition.ScreenRight:
return(new SimPoint(screenMaxX, 0.0));
case GravitySim.BodyStartPosition.ScreenTop:
return(new SimPoint(0.0, screenMaxY));
case GravitySim.BodyStartPosition.ScreenBottom:
return(new SimPoint(0.0, -screenMaxY));
case GravitySim.BodyStartPosition.CenterOfTheUniverse:
return(new SimPoint(0.0, 0.0));
case GravitySim.BodyStartPosition.RandomStagePosition:
return(new SimPoint(rand.Next((int)-simBoxMaxXY, (int)simBoxMaxXY),
rand.Next((int)-simBoxMaxXY, (int)simBoxMaxXY)));
case GravitySim.BodyStartPosition.RandomScreenPosition:
return(new SimPoint(rand.Next((int)-screenMaxX, (int)screenMaxX),
rand.Next((int)-screenMaxY, (int)screenMaxY)));
// This approach gives us higher density toward the center of the circle
case GravitySim.BodyStartPosition.RandomDenseCenterCircularCluster:
double length = rand.NextDouble() * simBoxMaxXY * 0.9;
double angle = rand.NextDouble() * Math.PI * 2.0; // radians
return(new SimPoint(length * Math.Cos(angle), length * Math.Sin(angle)));
// This approach gives us uniform density throughout the circle
case GravitySim.BodyStartPosition.RandomUniformDensityCircularCluster:
SimPoint newBodyPosition;
double limitXY = 0.9 * simBoxMaxXY;
do
{
newBodyPosition = new SimPoint(rand.Next((int)-limitXY, (int)limitXY),
rand.Next((int)-limitXY, (int)limitXY));
}while (newBodyPosition.Magnitude() > limitXY);
return(newBodyPosition);
default:
return(new SimPoint(0.0, 0.0));
}
}
// Use GravitySim.BodyStartPosition.RandomDenseCenterCircularCluster OR GravitySim.BodyStartPosition.RandomUniformDensityCircularCluster
// sizeFactor 1.0 = tiny, sizeFactor 5.0 = "normal"
public static void LoadXBodiesCircularCluster(GravitySim sim, int numBodies, double sizeFactor, Renderer.ColorScheme colorScheme, GravitySim.BodyStartPosition bodyStartPosition)
{
const double baseMass = 100000.0;
SetScenarioName(sim, String.Format("{0} Bodies Circular Cluster Scenario ({1})", numBodies, colorScheme));
Random rand = new Random();
sim.ClearSim();
sim.SetSimSpace(new SimulationSpace(SimulationSpace.Space.Toy));
for (int i = 0; i < numBodies; i++)
{
double size = rand.NextDouble() * 3.0 + 1.0; // Mass as square of size
sim.AddBody(size * size * baseMass, size * sizeFactor, RandomColor(colorScheme, rand), bodyStartPosition);
}
sim.SetMonitoredBody(numBodies - 1);
sim.SetMonitoredValues();
sim.SetAccelerationLimits(true, toySpaceScenariosDefaultAccelerationLimit, toySpaceScenariosDeaultMinimumSeparation);
}
