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mapgen stuff

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This commit is contained in:
Perttu Ahola 2011-02-05 14:55:16 +02:00
parent 7f2aa30bf2
commit ea6740e900
17 changed files with 239 additions and 3396 deletions
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230
src/utility.cpp
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@ -144,236 +144,6 @@ void mysrand(unsigned seed)
next = seed;
}
/*
PointAttributeList
*/
// Float with distance
struct DFloat
{
float v;
u32 d;
};
float PointAttributeList::getInterpolatedFloat(v2s16 p)
{
const u32 near_wanted_count = 5;
// Last is nearest, first is farthest
core::list<DFloat> near_list;
for(core::list<PointWithAttr>::Iterator
i = m_points.begin();
i != m_points.end(); i++)
{
PointWithAttr &pwa = *i;
u32 d = pwa.p.getDistanceFrom(p);
DFloat df;
df.v = pwa.attr.getFloat();
df.d = d;
// If near list is empty, add directly and continue
if(near_list.size() == 0)
{
near_list.push_back(df);
continue;
}
// Get distance of farthest in near list
u32 near_d = 100000;
if(near_list.size() > 0)
{
core::list<DFloat>::Iterator i = near_list.begin();
near_d = i->d;
}
/*
If point is closer than the farthest in the near list or
there are not yet enough points on the list
*/
if(d < near_d || near_list.size() < near_wanted_count)
{
// Find the right place in the near list and put it there
// Go from farthest to near in the near list
core::list<DFloat>::Iterator i = near_list.begin();
for(; i != near_list.end(); i++)
{
// Stop when i is at the first nearer node
if(i->d < d)
break;
}
// Add df to before i
if(i == near_list.end())
near_list.push_back(df);
else
near_list.insert_before(i, df);
// Keep near list at right size
if(near_list.size() > near_wanted_count)
{
core::list<DFloat>::Iterator j = near_list.begin();
near_list.erase(j);
}
}
}
// Return if no values found
if(near_list.size() == 0)
return 0.0;
/*
20:58:29 < tejeez> joka pisteelle a += arvo / etäisyys^6; b += 1 / etäisyys^6; ja
lopuks sit otetaan a/b
*/
float a = 0;
float b = 0;
for(core::list<DFloat>::Iterator i = near_list.begin();
i != near_list.end(); i++)
{
if(i->d == 0)
return i->v;
//float dd = pow((float)i->d, 6);
float dd = pow((float)i->d, 5);
float v = i->v;
//dstream<<"dd="<<dd<<", v="<<v<<std::endl;
a += v / dd;
b += 1 / dd;
}
return a / b;
}
#if 0
float PointAttributeList::getInterpolatedFloat(v3s16 p)
{
const u32 near_wanted_count = 2;
const u32 nearest_wanted_count = 2;
// Last is near
core::list<DFloat> near;
for(core::list<PointWithAttr>::Iterator
i = m_points.begin();
i != m_points.end(); i++)
{
PointWithAttr &pwa = *i;
u32 d = pwa.p.getDistanceFrom(p);
DFloat df;
df.v = pwa.attr.getFloat();
df.d = d;
// If near list is empty, add directly and continue
if(near_list.size() == 0)
{
near_list.push_back(df);
continue;
}
// Get distance of farthest in near list
u32 near_d = 100000;
if(near_list.size() > 0)
{
core::list<DFloat>::Iterator i = near_list.begin();
near_d = i->d;
}
/*
If point is closer than the farthest in the near list or
there are not yet enough points on the list
*/
if(d < near_d || near_list.size() < near_wanted_count)
{
// Find the right place in the near list and put it there
// Go from farthest to near in the near list
core::list<DFloat>::Iterator i = near_list.begin();
for(; i != near_list.end(); i++)
{
// Stop when i is at the first nearer node
if(i->d < d)
break;
}
// Add df to before i
if(i == near_list.end())
near_list.push_back(df);
else
near_list.insert_before(i, df);
// Keep near list at right size
if(near_list.size() > near_wanted_count)
{
core::list<DFloat>::Iterator j = near_list.begin();
near_list.erase(j);
}
}
}
// Return if no values found
if(near_list.size() == 0)
return 0.0;
/*
Get nearest ones
*/
u32 nearest_count = nearest_wanted_count;
if(nearest_count > near_list.size())
nearest_count = near_list.size();
core::list<DFloat> nearest;
{
core::list<DFloat>::Iterator i = near_list.getLast();
for(u32 j=0; j<nearest_count; j++)
{
nearest.push_front(*i);
i--;
}
}
/*
TODO: Try this:
20:58:29 < tejeez> joka pisteelle a += arvo / etäisyys^6; b += 1 / etäisyys^6; ja
lopuks sit otetaan a/b
*/
/*
Get total distance to nearest points
*/
float nearest_d_sum = 0;
for(core::list<DFloat>::Iterator i = nearest.begin();
i != nearest.end(); i++)
{
nearest_d_sum += (float)i->d;
}
/*
Interpolate a value between the first ones
*/
dstream<<"nearest.size()="<<nearest.size()<<std::endl;
float interpolated = 0;
for(core::list<DFloat>::Iterator i = nearest.begin();
i != nearest.end(); i++)
{
float weight;
if(nearest_d_sum > 0.001)
weight = (float)i->d / nearest_d_sum;
else
weight = 1. / nearest.size();
/*dstream<<"i->d="<<i->d<<" nearest_d_sum="<<nearest_d_sum
<<" weight="<<weight<<std::endl;*/
interpolated += weight * i->v;
}
return interpolated;
}
#endif
/*
blockpos: position of block in block coordinates
camera_pos: position of camera in nodes