bool PivotScaled(ScaleValue& sv)
{
ScaleValue noscale(Point3(1,1,1));
Point3 p = sv.s - noscale.s;
Point3 q(sv.q.x - noscale.q.x, sv.q.y - noscale.q.y, sv.q.z - noscale.q.z);
float w = sv.q.w - noscale.q.w;
float v = p.LengthSquared() + q.LengthSquared() + w * w;
return v > gTolerenceEpsilon;
}
bool IsScaled(Matrix3& tm)
{
Matrix3 t(1);
t = tm - t;
Point3 x = t.GetRow(0), y = t.GetRow(1), z = t.GetRow(2), u = t.GetRow(3);
float v = x.LengthSquared() + y.LengthSquared() + z.LengthSquared() + u.LengthSquared();
if(v > gTolerenceEpsilon)
return true;
else
return false;
}
// Calculate bounding sphere using average position of the points. Better fit but slower.
void CalcCenteredSphere(Mesh& mesh, Point3& center, float& radius)
{
int nv = mesh.getNumVerts();
Point3 sum(0.0f, 0.0f, 0.0f);
for (int i=0; i<nv; ++i)
sum += mesh.getVert(i);
center = sum / float(nv);
float radsq = 0.0f;
for (int i=0; i<nv; ++i){
Point3 diff = mesh.getVert(i) - center;
float mag = diff.LengthSquared();
radsq = max(radsq, mag);
}
radius = Sqrt(radsq);
}
Point3 plDistributor::IPerpAxis(const Point3& p) const
{
const float kMinLengthSquared = 1.e-1f;
int minAx = p.MinComponent();
Point3 ax(0,0,0);
ax[minAx] = 1.f;
Point3 perp = p ^ ax;
if( perp.LengthSquared() < kMinLengthSquared )
{
// hmm, think we might be screwed, but this shouldn't happen.
}
return perp = perp.FNormalize();
}
// Generate local to world from face info (pos, normal, etc)
Matrix3 plDistributor::IGenerateTransform(int iRepNode, int iFace, const Point3& pt, const Point3& bary) const
{
const float kMinVecLengthSq = 1.e-6f;
Matrix3 l2w(true);
// First, set the scale
Point3 scale;
switch( fScaleLock )
{
case kLockX | kLockY:
scale.x = fRand.RandRangeF(fScaleLo.x, fScaleHi.x);
scale.y = scale.x;
scale.z = fRand.RandRangeF(fScaleLo.z, fScaleHi.z);
break;
case kLockX | kLockY | kLockZ:
scale.x = fRand.RandRangeF(fScaleLo.x, fScaleHi.x);
scale.y = scale.z = scale.x;
break;
default:
scale.x = fRand.RandRangeF(fScaleLo.x, fScaleHi.x);
scale.y = fRand.RandRangeF(fScaleLo.y, fScaleHi.y);
scale.z = fRand.RandRangeF(fScaleLo.z, fScaleHi.z);
break;
}
l2w.Scale(scale);
// Next up, get the rotation.
// First we'll randomly rotate about local Z
float azimRot = fRand.RandMinusOneToOne() * fAzimuthRange;
Matrix3 azimMat;
azimMat.SetRotateZ(azimRot);
l2w = l2w * azimMat;
// Now align with the surface.
// Get the interpolated surface normal.
Point3 surfNorm = IGetSurfaceNormal(iFace, bary);
Matrix3 repNodeTM = fRepNodes[iRepNode]->GetNodeTM(TimeValue(0));
Point3 alignVec = repNodeTM.GetRow(2);
alignVec = alignVec * fWorldToSurfVec;
alignVec = FNormalize(alignVec);
Point3 norm = surfNorm + (alignVec - surfNorm) * fAlignWgt;
// The norm can come out of this zero length, if the surace normal
// is directly opposite the "natural" up direction and the weight
// is 50% (for example). In that case, this is just a bad place
// to drop this replicant.
if( norm.LengthSquared() < kMinVecLengthSq )
{
l2w.IdentityMatrix();
return l2w;
}
norm = norm.Normalize();
// Randomize through the cone around that.
Point3 rndNorm = norm;
Point3 rndDir = IPerpAxis(norm);
Point3 rndOut = rndDir ^ norm;
rndDir *= fRand.RandMinusOneToOne();
float len = sqrt(1.f - rndDir.LengthSquared());
rndOut *= len;
if( fRand.RandMinusOneToOne() < 0 )
rndOut *= -1.f;
Point3 rndPol = rndDir + rndOut;
float polScale = fRand.RandZeroToOne() * fTanPolarRange;
// Combine using the bunching factor
polScale = polScale * (1.f - fPolarBunch) + polScale * polScale * fPolarBunch;
rndPol *= polScale;
rndNorm += rndPol;
norm = rndNorm.Normalize();
// Have "up" alignment, now just generate random dir vector perpindicular to up
Point3 dir = repNodeTM.GetRow(1);
dir = dir * fWorldToSurfVec;
Point3 out = dir ^ norm;
if( out.LengthSquared() < kMinVecLengthSq )
{
if( fAzimuthRange < M_PI * 0.5f )
{
l2w.IdentityMatrix();
return l2w;
}
else
{
dir = IPerpAxis(norm);
out = dir ^ norm;
}
}
out = FNormalize(out);
dir = norm ^ out;
// If our "up" direction points into the surface, return an "up" direction
// tangent to the surface. Also, make the "dir" direction point out from
// the surface. So if the alignVec/fAlignWgt turns the replicant around
// to penetrate the surface, it just lies down instead.
//
// There's an early out here, for the case where the surface normal is
// exactly opposed to the destination normal. This usually means the
// surface normal is directly opposite the alignVec. In that
// case, we just want to bag it.
if( DotProd(norm, surfNorm) < 0 )
{
dir = surfNorm;
dir = dir.Normalize();
out = dir ^ norm;
if( out.LengthSquared() < kMinVecLengthSq )
{
l2w.IdentityMatrix();
return l2w;
}
out = out.Normalize();
norm = out ^ dir;
}
Matrix3 align;
align.Set(out, dir, norm, Point3(0,0,0));
l2w = l2w * align;
// Lastly, set the position.
Point3 pos = pt;
const float offset = fRand.RandRangeF(fOffsetMin, fOffsetMax);
pos += norm * offset;
l2w.Translate(pos);
l2w = l2w * fSurfNode->GetObjectTM(TimeValue(0));
return l2w;
}
