private void GenerateSamples(int amount = 10)
{
meshCollider.sharedMesh = currentPointCloud.mesh.mesh;
var camRay = camera.ScreenPointToRay(Input.mousePosition);
var dir = camRay.direction;
var(dist, _) = PolySurface.RayMarch(coefficients, camRay.origin, dir, 1000.0f, surface.Center);
var hit = camRay.origin + (dist + 0.001f) * camRay.direction;
hit = currentCenter - currentNormal * 0.001f;
dir = -currentNormal;
int count = 0;
while (count < amount)
{
int stepCount = 0;
var exit = TestDataGenerator.SimulatePath(
samplesRandom,
surface.Coefficients,
hit, dir,
surface.Center,
surface.g, surface.SigmaSReduced, surface.sigmaT,
distScale,
null,
ref stepCount);
if (exit != null)
{
count += 1;
var ray = new Ray(exit.Value, -PolySurface.GetNormalAt(surface.Coefficients, exit.Value, surface.Center));
if (autoProjectSamples && meshCollider.Raycast(ray, out var h, float.MaxValue))
{
var go = GameObject.Instantiate(samplePointPrefab, transform);
go.transform.position = h.point;
samples.Add(go);
//samples.Add(new MeshDBSample
//{
// position = h.point,
// gradient = -ray.direction,
//});
}
else
{
var go = GameObject.Instantiate(samplePointPrefab, transform);
go.transform.position = exit.Value;
samples.Add(go);
//samples.Add(new MeshDBSample
//{
// position = exit.Value,
// gradient = -ray.direction
//});
}
}
}
private void GetSamplesFromModel(Vector3 center, Vector3 normal, Vector3 direction)
{
Debug.Log("Start generator");
foreach (var go in samples)
{
GameObject.Destroy(go);
}
samples.Clear();
var coefficients = surface.Coefficients.ToArray();
var normalToZ = new Frame(normal);
var zToDirection = new Frame(-direction).Invert();
TestDataGenerator.RotatePolynomial(coefficients, normalToZ.x, normalToZ.y, normalToZ.z);
if (!incidentIsNormal)
{
TestDataGenerator.RotatePolynomial(coefficients, zToDirection.x, zToDirection.y, zToDirection.z);
}
string[] arguments = null;
string fileExe = null;
var model = string.IsNullOrWhiteSpace(modelVersion) ? $"{modelName}/final" : $"{modelName}/{modelVersion}";
switch (sampleSource)
{
case SampleSource.Cpp:
fileExe = @"D:\Bachelorarbeit\CppModelTest\x64\Release\CppModelTest.exe";
arguments = new string[]
{
model,
samplesToGenerate.ToString(),
modelStddev.ToString(),
$"{string.Join(",", coefficients)},{surface.alphaEff},{surface.g},{surface.ior}"
};
break;
case SampleSource.Python:
fileExe = "python.exe";
arguments = new string[]
{
@"D:\Bachelorarbeit\Bachelorarbeit\Model\generate_samples.py",
model,
samplesToGenerate.ToString(),
modelStddev.ToString(),
$"{string.Join(",", coefficients)},{surface.alphaEff},{surface.g},{surface.ior}"
};
break;
default:
fileExe = @"D:\Bachelorarbeit\CppModelTest\x64\Release\CppModelTest.exe";
arguments = new string[]
{
model,
samplesToGenerate.ToString(),
modelStddev.ToString(),
$"{string.Join(",", coefficients)},{surface.alphaEff},{surface.g},{surface.ior}"
};
break;
}
var p = new System.Diagnostics.Process();
p.StartInfo.FileName = fileExe;
p.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
p.StartInfo.WorkingDirectory = @"D:\Bachelorarbeit\Bachelorarbeit\Model";
p.StartInfo.UseShellExecute = false;
p.StartInfo.CreateNoWindow = true;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.Arguments = string.Join(" ", arguments.Select(a => $"\"{a}\""));
Debug.Log(p.StartInfo.Arguments);
var r = new System.Random();
p.OutputDataReceived += (sender, args) => {
if (args.Data != null && args.Data.StartsWith("# "))
{
var parts = args.Data.Substring(2).Split(',').Select(s => float.Parse(s)).ToArray();
var pos = new Vector3(parts[0], parts[1], parts[2]);
var n = PolySurface.GetNormalAt(coefficients, pos, Vector3.zero);
//pos = new Vector3(0, 0, (float)r.NextDouble());
if (!incidentIsNormal)
{
pos = zToDirection.ToMatrix() * pos;
n = zToDirection.ToMatrix() * n;
}
pos = normalToZ.ToMatrix() * pos;
n = normalToZ.ToMatrix() * n;
pos += center;
samplesTemp.Add(new MeshDBSample
{
position = pos,
gradient = n
});
}
};
p.Start();
p.BeginOutputReadLine();
process = p;
}
public static Vector3?SimulatePath(System.Random random, float[] coefficients, Vector3 origin, Vector3 direction, Vector3 center, float g, float sigmaSRed, float sigmaA, float distScale, Action <PathPoint> onInteraction, ref int stepCount)
{
direction = direction.normalized;
float maxDist = float.MaxValue;
maxDist = GetScatterDistance(random, sigmaSRed) * distScale;
float throughput = 1.0f;
for (int i = 0; i < 500; i++)
{
stepCount += 1;
var(dist, inside) = PolySurface.RayMarch(coefficients, origin, direction, maxDist, center);
var newPoint = origin + direction * dist;
var point = new PathPoint {
position = newPoint,
direction = direction
};
var normal = PolySurface.GetNormalAt(coefficients, newPoint, center);
origin = newPoint - normal * PolySurface.SURF_DIST * 2;
if (!inside)
{
// exited surface
return(newPoint);
}
direction = GetRandomNewDirection(random, g, direction);
// still inside, set random direction and maxDist
//if (g == 0) {
// direction = OnUnitSphere(random);
//} else {
// float rand = RandomRange(random, 0.0f, 1.0f);
// float cosAngle = InvIntPhaseFunction(rand, g);
// float theta = Mathf.Acos(cosAngle);
// float d = 1 / Mathf.Tan(theta);
// // Debug.Log($"rand: {rand}, cosAngle: {cosAngle}, theta: {theta}, d: {d}");
// if (d == float.PositiveInfinity) {
// // do nothing
// //direction = direction;
// } else if (d == float.NegativeInfinity) {
// direction = -direction;
// } else {
// var right = GetPerpendicular(direction).normalized;
// var up = Vector3.Cross(right, direction).normalized;
// var uv = InsideUnitCircle(random);
// point.uv = uv;
// point.right = right;
// point.up = up;
// // Debug.Log($"right: {right}, up: {up}, uv: {uv}");
// direction = uv.x * right + uv.y * up + d * direction;
// direction = direction.normalized;
// }
//}
// Debug.Log($"direction: {direction}");
maxDist = GetScatterDistance(random, sigmaSRed) * distScale;
point.direction = point.direction * Vector3.Dot(point.direction, direction * maxDist);
onInteraction?.Invoke(point);
float transmission = Mathf.Exp(-sigmaA * maxDist);
throughput = throughput * transmission;
// russian roulette
if (i > 5)
{
if ((float)random.NextDouble() > throughput)
{
return(null);
}
throughput = 1;
}
}
// reached max steps, ray counts as absorbed
return(null);
}
