private float[] CalculateSurfaceAreas(out float totalSurfaceArea)
{
int idx = 0;
totalSurfaceArea = 0.0f;
float[] surfaceAreas = new float[triangles.Length / 3];
for (int triangleIndex = 0; triangleIndex < triangles.Length; triangleIndex += 3)
{
Vector3 p1 = vertices[triangles[triangleIndex]];
Vector3 p2 = vertices[triangles[triangleIndex + 1]];
Vector3 p3 = vertices[triangles[triangleIndex + 2]];
// http://www.wikihow.com/Sample/Area-of-a-Triangle-Side-Length
float a = (p1 - p2).sqrMagnitude;
float b = (p1 - p3).sqrMagnitude;
float c = (p2 - p3).sqrMagnitude;
// faster with only 1 square root: http://www.iquilezles.org/blog/?p=1579
// A² = (2ab + 2bc + 2ca – a² – b² – c²)/16
float areaSquared = ((2.0f * a * b) + (2.0f * b * c) + (2.0f * c * a) - (a * a) - (b * b) - (c * c)) / 16.0f;
float area = PathGenerator.SquareRoot(areaSquared);
surfaceAreas[idx++] = area;
totalSurfaceArea += area;
}
return(surfaceAreas);
}
public Vector3 RandomDirection3D(System.Random r)
{
float z = (2.0f * (float)r.NextDouble()) - 1.0f; // z is in the range [-1,1]
Vector2 planar = RandomDirection2D(r) * PathGenerator.SquareRoot(1.0f - (z * z));
return(new Vector3(planar.x, planar.y, z));
}
public void GenerateLightningBoltPath(LightningBolt bolt, Vector3 start, Vector3 end, LightningBoltParameters p)
{
if (p.Points.Count < 2)
{
Debug.LogError("Lightning path should have at least two points");
return;
}
int generation = p.Generations;
int totalGenerations = generation;
float offsetAmount, d;
int smoothingFactor = p.SmoothingFactor - 1;
Vector3 distance, randomVector;
LightningBoltSegmentGroup group = bolt.AddGroup();
group.LineWidth = p.TrunkWidth;
group.Generation = generation--;
group.EndWidthMultiplier = p.EndWidthMultiplier;
group.Color = Color.white;
p.Start = p.Points[0] + start;
p.End = p.Points[p.Points.Count - 1] + end;
end = p.Start;
for (int i = 1; i < p.Points.Count; i++)
{
start = end;
end = p.Points[i];
distance = (end - start);
d = PathGenerator.SquareRoot(distance.sqrMagnitude);
if (p.ChaosFactor > 0.0f)
{
if (bolt.CameraMode == CameraMode.Perspective)
{
end += (d * p.ChaosFactor * RandomDirection3D(p.Random));
}
else if (bolt.CameraMode == CameraMode.OrthographicXY)
{
end += (d * p.ChaosFactor * RandomDirection2D(p.Random));
}
else
{
end += (d * p.ChaosFactor * RandomDirection2DXZ(p.Random));
}
distance = (end - start);
}
group.Segments.Add(new LightningBoltSegment {
Start = start, End = end
});
offsetAmount = d * p.ChaosFactor;
RandomVector(bolt, ref start, ref end, offsetAmount, p.Random, out randomVector);
if (ShouldCreateFork(p, generation, totalGenerations))
{
Vector3 branchVector = distance * p.ForkMultiplier() * smoothingFactor * 0.5f;
Vector3 forkEnd = end + branchVector + randomVector;
GenerateLightningBoltStandard(bolt, start, forkEnd, generation, totalGenerations, 0.0f, p);
}
if (--smoothingFactor == 0)
{
smoothingFactor = p.SmoothingFactor - 1;
}
}
}