/// <summary>
/// Light probe runtime data is auto-computed when lightprobes are added/removed. If you move them at runtime, please call this method.
/// </summary>
/// <remarks>
/// This will also update coefficients.
/// </remarks>
public void UpdateLightProbePositions()
{
RuntimeData = null;
needPositionUpdate = false;
// Initial load
try
{
// Collect LightProbes
var lightProbes = new FastList <LightProbeComponent>();
foreach (var lightProbe in ComponentDatas)
{
lightProbes.Add(lightProbe.Key);
}
// Need at least 4 light probes to form a tetrahedron
if (lightProbes.Count < 4)
{
return;
}
RuntimeData = LightProbeGenerator.GenerateRuntimeData(lightProbes);
}
catch
{
// Allow failures
// TODO: Log
}
}
public static unsafe void UpdateCoefficients(LightProbeRuntimeData runtimeData)
{
fixed(Color3 *destColors = runtimeData.Coefficients)
{
for (var lightProbeIndex = 0; lightProbeIndex < runtimeData.LightProbes.Length; lightProbeIndex++)
{
var lightProbe = runtimeData.LightProbes[lightProbeIndex];
// Copy coefficients
if (lightProbe.Coefficients != null)
{
var lightProbeCoefStart = lightProbeIndex * LambertHamonicOrder * LambertHamonicOrder;
for (var index = 0; index < LambertHamonicOrder * LambertHamonicOrder; index++)
{
destColors[lightProbeCoefStart + index] = index < lightProbe.Coefficients.Count ? lightProbe.Coefficients[index] : new Color3();
}
}
}
}
}
public static unsafe LightProbeRuntimeData GenerateRuntimeData(FastList <LightProbeComponent> lightProbes)
{
// TODO: Better check: coplanar, etc... (maybe the check inside BowyerWatsonTetrahedralization might be enough -- tetrahedron won't be in positive order)
if (lightProbes.Count < 4)
{
throw new InvalidOperationException("Can't generate lightprobes if less than 4 of them exists.");
}
var lightProbePositions = new FastList <Vector3>();
var lightProbeCoefficients = new Color3[lightProbes.Count * LambertHamonicOrder * LambertHamonicOrder];
fixed(Color3 *destColors = lightProbeCoefficients)
{
for (var lightProbeIndex = 0; lightProbeIndex < lightProbes.Count; lightProbeIndex++)
{
var lightProbe = lightProbes[lightProbeIndex];
// Copy light position
lightProbePositions.Add(lightProbe.Entity.Transform.WorldMatrix.TranslationVector);
// Copy coefficients
if (lightProbe.Coefficients != null)
{
var lightProbeCoefStart = lightProbeIndex * LambertHamonicOrder * LambertHamonicOrder;
for (var index = 0; index < LambertHamonicOrder * LambertHamonicOrder; index++)
{
destColors[lightProbeCoefStart + index] = index < lightProbe.Coefficients.Count ? lightProbe.Coefficients[index] : new Color3();
}
}
}
}
// Generate light probe structure
var tetra = new BowyerWatsonTetrahedralization();
var tetraResult = tetra.Compute(lightProbePositions);
var matrices = new Vector4[tetraResult.Tetrahedra.Count * 3];
var probeIndices = new Int4[tetraResult.Tetrahedra.Count];
// Prepare data for GPU: matrices and indices
for (int i = 0; i < tetraResult.Tetrahedra.Count; ++i)
{
var tetrahedron = tetraResult.Tetrahedra[i];
var tetrahedronMatrix = Matrix.Identity;
// Compute the tetrahedron matrix
// https://en.wikipedia.org/wiki/Barycentric_coordinate_system#Barycentric_coordinates_on_tetrahedra
var vertex3 = tetraResult.Vertices[tetrahedron.Vertices[3]];
*((Vector3 *)&tetrahedronMatrix.M11) = tetraResult.Vertices[tetrahedron.Vertices[0]] - vertex3;
*((Vector3 *)&tetrahedronMatrix.M12) = tetraResult.Vertices[tetrahedron.Vertices[1]] - vertex3;
*((Vector3 *)&tetrahedronMatrix.M13) = tetraResult.Vertices[tetrahedron.Vertices[2]] - vertex3;
tetrahedronMatrix.Invert(); // TODO: Optimize 3x3 invert
tetrahedronMatrix.Transpose();
// Store position of last vertex in last row
tetrahedronMatrix.M41 = vertex3.X;
tetrahedronMatrix.M42 = vertex3.Y;
tetrahedronMatrix.M43 = vertex3.Z;
matrices[i * 3 + 0] = tetrahedronMatrix.Column1;
matrices[i * 3 + 1] = tetrahedronMatrix.Column2;
matrices[i * 3 + 2] = tetrahedronMatrix.Column3;
probeIndices[i] = *(Int4 *)tetrahedron.Vertices;
}
var lightProbesCopy = new LightProbeComponent[lightProbes.Count];
for (int i = 0; i < lightProbes.Count; ++i)
{
lightProbesCopy[i] = lightProbes[i];
}
var result = new LightProbeRuntimeData
{
LightProbes = lightProbesCopy,
Vertices = tetraResult.Vertices,
UserVertexCount = tetraResult.UserVertexCount,
Tetrahedra = tetraResult.Tetrahedra,
Faces = tetraResult.Faces,
Coefficients = lightProbeCoefficients,
Matrices = matrices,
LightProbeIndices = probeIndices,
};
return(result);
}
