//[/commonTester]
//[commonPerfTester]
public static void Performance(ISimulatorTester simulator, int numBodies)
{
const float clusterScale = 1.0f;
const float velocityScale = 1.0f;
const float deltaTime = 0.001f;
const float softeningSquared = 0.00125f;
const float damping = 0.9995f;
const int steps = 10;
Console.WriteLine("Perfomancing {0} with {1} bodies...", simulator.Description, numBodies);
float4[] pos, vel;
BodyInitializer.Initialize(new BodyInitializer1(), clusterScale, velocityScale, numBodies,
out pos, out vel);
simulator.Integrate(pos, vel, numBodies, deltaTime, softeningSquared, damping, steps);
}
static public void Initialize(BodyInitializer initializer, float clusterScale,
float velocityScale, int numBodies,
out float4[] positions, out float4[] velocities)
{
var pscale = clusterScale * Math.Max(1.0f, numBodies / 1024.0f);
var vscale = velocityScale * pscale;
initializer.NumBodies = numBodies;
initializer.PScale = pscale;
initializer.VScale = vscale;
positions = Enumerable.Range(0, numBodies).Select(initializer.Position).ToArray();
velocities = positions.Select(initializer.Velocity).ToArray();
// now we try to adjust velocity to make total momentum = zero.
var momentums = velocities.Select(Momentum).ToArray();
var totalMomentum = momentums.Aggregate(new float4(0.0f, 0.0f, 0.0f, 0.0f),
(accum, momentum) =>
new float4(accum.x + momentum.x,
accum.y + momentum.y,
accum.z + momentum.z,
accum.w + momentum.w));
Console.WriteLine("total momentum and mass 0 = {0}", totalMomentum);
var len = velocities.Length;
// adjust velocities
velocities = velocities.Select((vel, i) => new float4(
vel.x - totalMomentum.x / len / vel.w,
vel.y - totalMomentum.y / len / vel.w,
vel.z - totalMomentum.z / len / vel.w,
vel.w)).ToArray();
// see total momentum after adjustment
momentums = velocities.Select(Momentum).ToArray();
totalMomentum = momentums.Aggregate(new float4(0.0f, 0.0f, 0.0f, 0.0f),
(accum, momentum) =>
new float4(accum.x + momentum.x,
accum.y + momentum.y,
accum.z + momentum.z,
accum.w + momentum.w));
Console.WriteLine("total momentum and mass 1 = {0}", totalMomentum);
}
//[commonTester]
public static void Test(
BodyInitializer initializer,
ISimulatorTester expectedSimulator,
ISimulatorTester actualSimulator,
int numBodies)
{
const float clusterScale = 1.0f;
const float velocityScale = 1.0f;
const float deltaTime = 0.001f;
const float softeningSquared = 0.00125f;
const float damping = 0.9995f;
const int steps = 5;
Console.WriteLine("Testing {0} against {1} with {2} bodies...",
actualSimulator.Description,
expectedSimulator.Description,
numBodies);
Console.WriteLine("Using body initializer {0}...", initializer);
float4[] expectedPos, expectedVel;
BodyInitializer.Initialize(initializer, clusterScale, velocityScale, numBodies,
out expectedPos, out expectedVel);
for (var i = 0; i < steps; i++)
{
const double tol = 1e-5;
var actualPos = new float4[numBodies];
var actualVel = new float4[numBodies];
Array.Copy(expectedPos, actualPos, numBodies);
Array.Copy(expectedVel, actualVel, numBodies);
expectedSimulator.Integrate(expectedPos, expectedVel, numBodies, deltaTime,
softeningSquared, damping, 1);
actualSimulator.Integrate(actualPos, actualVel, numBodies, deltaTime,
softeningSquared, damping, 1);
for (var j = 0; j < expectedPos.Length; j++)
{
Assert.AreEqual(actualPos[j].x, expectedPos[j].x, tol);
Assert.AreEqual(actualPos[j].y, expectedPos[j].y, tol);
Assert.AreEqual(actualPos[j].z, expectedPos[j].z, tol);
Assert.AreEqual(actualPos[j].w, expectedPos[j].w, tol);
}
}
}
static public void Initialize(BodyInitializer initializer, float clusterScale,
float velocityScale, int numBodies,
out float4[] positions, out float4[] velocities)
{
var pscale = clusterScale*Math.Max(1.0f, numBodies/1024.0f);
var vscale = velocityScale*pscale;
initializer.NumBodies = numBodies;
initializer.PScale = pscale;
initializer.VScale = vscale;
positions = Enumerable.Range(0, numBodies).Select(initializer.Position).ToArray();
velocities = positions.Select(initializer.Velocity).ToArray();
// now we try to adjust velocity to make total momentum = zero.
var momentums = velocities.Select(Momentum).ToArray();
var totalMomentum = momentums.Aggregate(new float4(0.0f, 0.0f, 0.0f, 0.0f),
(accum, momentum) =>
new float4(accum.x + momentum.x,
accum.y + momentum.y,
accum.z + momentum.z,
accum.w + momentum.w));
Console.WriteLine("total momentum and mass 0 = {0}", totalMomentum);
var len = velocities.Length;
// adjust velocities
velocities = velocities.Select((vel, i) => new float4(
vel.x - totalMomentum.x / len / vel.w,
vel.y - totalMomentum.y / len / vel.w,
vel.z - totalMomentum.z / len / vel.w,
vel.w)).ToArray();
// see total momentum after adjustment
momentums = velocities.Select(Momentum).ToArray();
totalMomentum = momentums.Aggregate(new float4(0.0f, 0.0f, 0.0f, 0.0f),
(accum, momentum) =>
new float4(accum.x + momentum.x,
accum.y + momentum.y,
accum.z + momentum.z,
accum.w + momentum.w));
Console.WriteLine("total momentum and mass 1 = {0}", totalMomentum);
}
//[commonTester]
public static void Test(
BodyInitializer initializer,
ISimulatorTester expectedSimulator,
ISimulatorTester actualSimulator,
int numBodies)
{
const float clusterScale = 1.0f;
const float velocityScale = 1.0f;
const float deltaTime = 0.001f;
const float softeningSquared = 0.00125f;
const float damping = 0.9995f;
const int steps = 5;
Console.WriteLine("Testing {0} against {1} with {2} bodies...",
actualSimulator.Description,
expectedSimulator.Description,
numBodies);
Console.WriteLine("Using body initializer {0}...", initializer);
float4[] expectedPos, expectedVel;
BodyInitializer.Initialize(initializer, clusterScale, velocityScale, numBodies,
out expectedPos, out expectedVel);
for (var i = 0; i < steps; i++)
{
const double tol = 1e-5;
var actualPos = new float4[numBodies];
var actualVel = new float4[numBodies];
Array.Copy(expectedPos, actualPos, numBodies);
Array.Copy(expectedVel, actualVel, numBodies);
expectedSimulator.Integrate(expectedPos, expectedVel, numBodies, deltaTime,
softeningSquared, damping, 1);
actualSimulator.Integrate(actualPos, actualVel, numBodies, deltaTime,
softeningSquared, damping, 1);
for (var j = 0; j < expectedPos.Length; j++)
{
Assert.AreEqual(actualPos[j].x, expectedPos[j].x, tol);
Assert.AreEqual(actualPos[j].y, expectedPos[j].y, tol);
Assert.AreEqual(actualPos[j].z, expectedPos[j].z, tol);
Assert.AreEqual(actualPos[j].w, expectedPos[j].w, tol);
}
}
}
//[/LockPositions]
public SimWindow() : base(800, 600, GraphicsMode.Default, "Gravitational n-body simulation")
{
_numBodies = 256 * 64;
const float clusterScale = 1.0f;
const float velocityScale = 1.0f;
_deltaTime = 0.001f;
_softeningSquared = 0.00125f;
_damping = 0.9995f;
//[CreateWorker]
_worker = Worker.CreateByFunc(Generate);
//[/CreateWorker]
_stopwatch = Stopwatch.StartNew();
_fpsCalcLag = 128;
_frameCounter = 0;
//[CreateSimulatros]
_simulators = new Queue <ISimulator>();
var target = GPUModuleTarget.Worker(_worker);
var simulatorGpuDynamicBlockSizeModule = new GpuDynamicSimulatorModule(target); // need dispose
var simulatorGpuDynamicBlockSize64 = simulatorGpuDynamicBlockSizeModule.Create(64);
var simulatorGpuDynamicBlockSize128 = simulatorGpuDynamicBlockSizeModule.Create(128);
var simulatorGpuDynamicBlockSize256 = simulatorGpuDynamicBlockSizeModule.Create(256);
var simulatorGpuDynamicBlockSize512 = simulatorGpuDynamicBlockSizeModule.Create(512);
var simulatorGpuStaticBlockSizeModule64 = new GpuStaticSimulatorModule64(target); // need dispose
var simulatorGpuStaticBlockSizeModule128 = new GpuStaticSimulatorModule128(target); // need dispose
var simulatorGpuStaticBlockSizeModule256 = new GpuStaticSimulatorModule256(target); // need dispose
var simulatorGpuStaticBlockSizeModule512 = new GpuStaticSimulatorModule512(target); // need dispose
// First, enquene one simulator which is 256 blocksize so we can compare with C code for performance.
_simulators.Enqueue(simulatorGpuStaticBlockSizeModule256);
// Enqueue several dynamic block size simulators.
_simulators.Enqueue(simulatorGpuDynamicBlockSize64);
_simulators.Enqueue(simulatorGpuDynamicBlockSize128);
_simulators.Enqueue(simulatorGpuDynamicBlockSize256);
_simulators.Enqueue(simulatorGpuDynamicBlockSize512);
// Enqueue several static block size simulators.
_simulators.Enqueue(simulatorGpuStaticBlockSizeModule64);
_simulators.Enqueue(simulatorGpuStaticBlockSizeModule128);
_simulators.Enqueue(simulatorGpuStaticBlockSizeModule256);
_simulators.Enqueue(simulatorGpuStaticBlockSizeModule512);
// We do not enqueue any cpu simulator as it is much too slow.
//_simulators.Enqueue(new CpuSimulator(_worker, _numBodies));
_disposeSimulators = () =>
{
simulatorGpuDynamicBlockSizeModule.Dispose();
simulatorGpuStaticBlockSizeModule64.Dispose();
simulatorGpuStaticBlockSizeModule128.Dispose();
simulatorGpuStaticBlockSizeModule256.Dispose();
simulatorGpuStaticBlockSizeModule512.Dispose();
};
_simulator = _simulators.Dequeue();
//[/CreateSimulatros]
//[CreateBuffers]
_buffers = new uint[2];
for (var i = 0; i < _buffers.Length; i++)
{
_buffers[i] = 0;
}
GL.GenBuffers(_buffers.Length, _buffers);
foreach (var buffer in _buffers)
{
GL.BindBuffer(BufferTarget.ArrayBuffer, buffer);
GL.BufferData(BufferTarget.ArrayBuffer,
(IntPtr)(Microsoft.FSharp.Core.Operators.SizeOf <float4>() * _numBodies),
IntPtr.Zero, BufferUsageHint.DynamicDraw);
var size = 0;
unsafe
{
GL.GetBufferParameter(BufferTarget.ArrayBuffer, BufferParameterName.BufferSize, &size);
}
if (size != Microsoft.FSharp.Core.Operators.SizeOf <float4>() * _numBodies)
{
throw new Exception("Pixel Buffer Object allocation failed!");
}
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
CUDAInterop.cuSafeCall(CUDAInterop.cuGLRegisterBufferObject(buffer));
}
_resources = new IntPtr[_buffers.Length];
for (var i = 0; i < _buffers.Length; i++)
{
var res = IntPtr.Zero;
unsafe
{
CUDAInterop.cuSafeCall(CUDAInterop.cuGraphicsGLRegisterBuffer(&res, _buffers[i], 0u));
}
_resources[i] = res;
}
//[/CreateBuffers]
//[FinalizeGL]
_vel = _worker.Malloc <float4>(_numBodies);
float4[] hpos, hvel;
BodyInitializer.Initialize(new BodyInitializer3(), clusterScale, velocityScale, _numBodies,
out hpos, out hvel);
_worker.Scatter(hvel, _vel.Ptr, Microsoft.FSharp.Core.FSharpOption <int> .None,
Microsoft.FSharp.Core.FSharpOption <int> .None);
LockPos(
(pos0, pos1) =>
_worker.Scatter(hpos, pos1, Microsoft.FSharp.Core.FSharpOption <int> .None,
Microsoft.FSharp.Core.FSharpOption <int> .None));
Help();
Description();
//[/FinalizeGL]
}
