public NbodyPanel(
int width, // width of the panel
int height, // height of the panel
float xMin, // the smallest visible x-coordinate
float xMax, // the largest visible x-coordinate
float yMin, // the smallest visible y-coordinate
float yMax, // the largest visible y-coordinate
float dt, // the time step-size
Body[] bodies, // the bodies to be shown
bool parallel // should the calculations be done in parallel
)
{
this.Size = new Size(width, height);
this.DoubleBuffered = true;
this.BackColor = Color.Black;
float xScale = (float)(width / (xMax - xMin));
float yScale = (float)(height / (yMax - yMin));
float xTranslate = (float)Math.Abs(xMin * xScale);
float yTranslate = (float)Math.Abs(yMin * yScale);
float planetRadius = ((xMax - xMin) / width) * 10;
Timer timer = new Timer();
timer.Interval = 1;
timer.Tick += delegate(Object sender, EventArgs e)
{
Bitmap bmpNew = new Bitmap(width, height);
Graphics g = Graphics.FromImage(bmpNew);
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
g.Transform = new System.Drawing.Drawing2D.Matrix(xScale, 0, 0, yScale, xTranslate, yTranslate);
if (parallel)
{
NBodySolver.ParallelCalcForceAndUpdate(bodies, dt);
}
else
{
NBodySolver.SequentialCalcForceAndUpdate(bodies, dt);
}
NBodySolver.SequentialDraw(bodies, g, planetRadius);
this.bmp = bmpNew;
Refresh();
};
timer.Start();
}
private static void NBodyConsole()
{
int N = 10000;
int steps = 1;
double dt = 100000;
Body[] bodies = NBodySolver.GenerateRandomBodies(N);
// To make a fair comparison, we call
// each method once, to let the JIT kick in
NBodySolver.ParallelCalcForceAndUpdate(bodies, dt);
NBodySolver.SequentialCalcForceAndUpdate(bodies, dt);
Console.WriteLine("Starting parallel N-body solver...");
long start = DateTime.Now.Ticks / 10000;
for (int i = 0; i < steps; i++)
{
NBodySolver.ParallelCalcForceAndUpdate(bodies, dt);
}
long end = DateTime.Now.Ticks / 10000;
long tPar = end - start;
Console.WriteLine("Time spent: " + tPar);
Console.WriteLine("Starting sequential N-body solver...");
start = DateTime.Now.Ticks / 10000;
for (int i = 0; i < steps; i++)
{
NBodySolver.SequentialCalcForceAndUpdate(bodies, dt);
}
end = DateTime.Now.Ticks / 10000;
long tSeq = end - start;
Console.WriteLine("Time spent: " + tSeq);
Console.WriteLine("Speed up: " + ((double)tSeq / tPar));
}
