/// <summary>
/// Gets a bounding volume transformed by a matrix.
/// </summary>
/// <param name="m">The matrix to transform by.</param>
/// <returns>The transformed box.</returns>
/// <see cref="TransformProjectBy"/>
public FBox TransformBy(FMatrix m)
{
// if we are not valid, return another invalid box.
if (!IsValid)
{
return(default(FBox));
}
FVector vecMin = Min;
FVector vecMax = Max;
FVector m0 = m.GetRow(0);
FVector m1 = m.GetRow(1);
FVector m2 = m.GetRow(2);
FVector m3 = m.GetRow(3);
FVector half = new FVector(0.5f, 0.5f, 0.5f);
FVector origin = (vecMax + vecMin) * half;
FVector extent = (vecMax - vecMin) * half;
FVector newOrigin = FVector.Replicate(origin, 0) * m0;
newOrigin += (FVector.Replicate(origin, 1) * m1);
newOrigin += (FVector.Replicate(origin, 2) * m2);
newOrigin += m3;
FVector newExtent = (FVector.Replicate(extent, 0) * m0).GetAbs();
newExtent += (FVector.Replicate(extent, 1) * m1).GetAbs();
newExtent += (FVector.Replicate(extent, 2) * m2).GetAbs();
FVector newVecMin = newOrigin - newExtent;
FVector newVecMax = newOrigin + newExtent;
FBox newBox;
newBox.Min = newVecMin;
newBox.Max = newVecMax;
newBox.isValid = 1;
return(newBox);
}
/// <summary>
/// Gets a bounding volume transformed by a matrix.
/// </summary>
/// <param name="m">The matrix.</param>
/// <returns>The transformed volume.</returns>
public FBoxSphereBounds TransformBy(FMatrix m)
{
FBoxSphereBounds result;
FVector vecOrigin = Origin;
FVector vecExtent = BoxExtent;
FVector m0 = m.GetRow(0);
FVector m1 = m.GetRow(1);
FVector m2 = m.GetRow(2);
FVector m3 = m.GetRow(3);
FVector newOrigin = FVector.Replicate(vecOrigin, 0) * m0;
newOrigin += (FVector.Replicate(vecOrigin, 1) * m1);
newOrigin += (FVector.Replicate(vecOrigin, 2) * m2);
newOrigin = newOrigin + m3;
FVector newExtent = (FVector.Replicate(vecExtent, 0) * m0).GetAbs();
newExtent += (FVector.Replicate(vecExtent, 1) * m1).GetAbs();
newExtent += (FVector.Replicate(vecExtent, 2) * m2).GetAbs();
result.BoxExtent = newExtent;
result.Origin = newOrigin;
FVector maxRadius = m0 * m0;
maxRadius += m1 * m1;
maxRadius += m2 * m2;
maxRadius = FVector.ComponentMax(FVector.ComponentMax(maxRadius, FVector.Replicate(maxRadius, 1)), FVector.Replicate(maxRadius, 2));
result.SphereRadius = FMath.Sqrt(maxRadius[0]) * SphereRadius;
// For non-uniform scaling, computing sphere radius from a box results in a smaller sphere.
float boxExtentMagnitude = FMath.Sqrt(FVector.DotProduct(newExtent, newExtent));
result.SphereRadius = FMath.Min(result.SphereRadius, boxExtentMagnitude);
result.DiagnosticCheckNaN();
return(result);
}
