bool plDistributor::IFailsProbBitmap(int iFace, const Point3& bary) const
{
// If we don't have a probability map, or we don't have
// valid coordinates into it, just return false. That is,
// with no valid probability map, everything goes.
int uvwChan = 1;
Matrix3 uvtrans(true);
Bitmap* bm = nil;
UINT filtType = BMM_FILTER_PYRAMID;
if( fProbBitmapTex )
{
uvwChan = fProbBitmapTex->GetMapChannel();
fProbBitmapTex->GetUVTransform(uvtrans);
bm = fProbBitmapTex->GetBitmap(TimeValue(0));
if( bm && !bm->HasFilter() )
{
switch( fProbBitmapTex->GetFilterType() )
{
default:
case FILTER_PYR:
filtType = BMM_FILTER_PYRAMID;
break;
case FILTER_SAT:
filtType = BMM_FILTER_SUM;
break;
case FILTER_NADA:
filtType = BMM_FILTER_NONE;
break;
}
}
}
else if( fProbLayerTex )
{
uvwChan = fProbLayerTex->GetMapChannel();
fProbLayerTex->GetUVTransform(uvtrans);
bm = fProbLayerTex->GetBitmap(TimeValue(0));
}
if( !bm )
return false;
if( !bm->HasFilter() )
bm->SetFilter(filtType);
bm->PrepareGChannels(&bm->Storage()->bi);
if( !fSurfMesh->mapSupport(uvwChan) )
return false;
if( !fSurfMesh->mapFaces(uvwChan) || !fSurfMesh->mapVerts(uvwChan) )
return false;
// Lookup the appropriate texel value
Point3 uvw;
uvw = fSurfMesh->mapVerts(uvwChan)[fSurfMesh->mapFaces(uvwChan)[iFace].getTVert(0)] * bary[0];
uvw += fSurfMesh->mapVerts(uvwChan)[fSurfMesh->mapFaces(uvwChan)[iFace].getTVert(1)] * bary[1];
uvw += fSurfMesh->mapVerts(uvwChan)[fSurfMesh->mapFaces(uvwChan)[iFace].getTVert(2)] * bary[2];
uvw = uvw * uvtrans;
float fu = uvw.x - int(uvw.x);
if( fu < 0 )
fu += 1.f;
float fv = 1.0f - (uvw.y - int(uvw.y));
if( fv < 0 )
fv += 1.f;
float du = 1.f / bm->Width();
float dv = 1.f / bm->Height();
BMM_Color_fl evCol;
bm->GetFiltered(fu, fv, du, dv, &evCol);
float frac;
switch( fProbColorChan )
{
case kRed:
frac = evCol.r;
break;
case kGreen:
frac = evCol.g;
break;
case kBlue:
frac = evCol.b;
break;
case kAlpha:
frac = evCol.a;
break;
case kAverageRedGreen:
frac = (evCol.r + evCol.g) / 2.f;
break;
case kAverageRedGreenTimesAlpha:
frac = (evCol.r + evCol.g) / 2.f * evCol.a;
break;
case kAverage:
frac = (evCol.r + evCol.g + evCol.b ) / 3.f;
break;
case kAverageTimesAlpha:
frac = (evCol.r + evCol.g + evCol.b ) / 3.f * evCol.a;
break;
case kMax:
case kMaxColor:
frac = hsMaximum(evCol.r, hsMaximum(evCol.g, evCol.b));
break;
case kMaxColorTimesAlpha:
frac = hsMaximum(evCol.r, hsMaximum(evCol.g, evCol.b)) * evCol.a;
break;
case kMaxRedGreen:
frac = hsMaximum(evCol.r, evCol.g);
break;
case kMaxRedGreenTimesAlpha:
frac = hsMaximum(evCol.r, evCol.g) * evCol.a;
break;
}
if( fProbRemapFromHi != fProbRemapFromLo )
frac = fProbRemapToLo + (frac - fProbRemapFromLo) / (fProbRemapFromHi - fProbRemapFromLo) * (fProbRemapToHi - fProbRemapToLo);
else
frac = frac > fProbRemapFromHi ? fProbRemapToHi : fProbRemapToLo;
return frac < fRand.RandZeroToOne();
}
