RenderSet::references_t RenderSet::
computeChildrenRenderSet( Reference ref )
{
references_t R;
RenderInfo::LevelOfDetal lod = render_info->testLod (ref );
switch(lod) {
case RenderInfo::Lod_NeedBetterF:
R |= computeChildrenRenderSet( ref.bottom() );
R |= computeChildrenRenderSet( ref.top() );
break;
case RenderInfo::Lod_NeedBetterT:
R |= computeChildrenRenderSet( ref.left() );
if ( render_info->region(ref.right ()).a.time < L) {
R |= computeChildrenRenderSet( ref.right() );
}
break;
case RenderInfo::Lod_Ok:
R |= ref;
break;
case RenderInfo::Lod_Invalid: // ref is not within the current view frustum
break;
}
return R;
}
RenderInfo::LevelOfDetal RenderInfo::
testLod( Reference ref ) const
{
float timePixels, scalePixels;
Region r = RegionFactory ( bl )(ref);
if (!computePixelsPerUnit( r, timePixels, scalePixels ))
return Lod_Invalid;
if(0) if (-10==ref.log2_samples_size[0] && -8==ref.log2_samples_size[1]) {
fprintf(stdout, "Ref (%d,%d)\t%g\t%g\n", ref.block_index[0], ref.block_index[1], timePixels,scalePixels);
fflush(stdout);
}
GLdouble needBetterF, needBetterT;
if (0==scalePixels)
needBetterF = 1.01;
else
needBetterF = scalePixels / (redundancy*bl.texels_per_column ());
if (0==timePixels)
needBetterT = 1.01;
else
needBetterT = timePixels / (redundancy*bl.texels_per_row ());
if (!ReferenceInfo(ref.top(), bl, vp).boundsCheck(ReferenceInfo::BoundsCheck_HighS) &&
!ReferenceInfo(ref.bottom(), bl, vp).boundsCheck(ReferenceInfo::BoundsCheck_HighS))
needBetterF = 0;
if (!ReferenceInfo(ref.left(), bl, vp).boundsCheck(ReferenceInfo::BoundsCheck_HighT))
needBetterT = 0;
if ( needBetterF > needBetterT && needBetterF > 1 )
return Lod_NeedBetterF;
else if ( needBetterT > 1 )
return Lod_NeedBetterT;
else
return Lod_Ok;
}
Reference RenderSet::
computeRefAt( Heightmap::Position p, Reference entireHeightmap ) const
{
Reference ref = entireHeightmap;
// The first 'ref' will be a super-ref containing all other refs, thus
// containing 'p' too. This while-loop zooms in on a ref containing
// 'p' with enough details.
// If 'p' is not within entireHeightmap this algorithm will choose some ref
// along the border closest to the point 'p'.
while (true)
{
RenderInfoI::LevelOfDetal lod = render_info->testLod(ref);
Region r = render_info->region(ref);
switch(lod)
{
case RenderInfoI::Lod_NeedBetterF:
if ((r.a.scale+r.b.scale)/2 > p.scale)
ref = ref.bottom();
else
ref = ref.top();
break;
case RenderInfoI::Lod_NeedBetterT:
if ((r.a.time+r.b.time)/2 > p.time)
ref = ref.left();
else
ref = ref.right();
break;
default:
return ref;
}
}
}
