void cCaveTunnel::Randomize(cNoise & a_Noise)
{
// Repeat 4 times:
for (int i = 0; i < 4; i++)
{
// For each already present point, insert a point in between it and its predecessor, shifted randomly.
int PrevX = m_Points.front().m_BlockX;
int PrevY = m_Points.front().m_BlockY;
int PrevZ = m_Points.front().m_BlockZ;
int PrevR = m_Points.front().m_Radius;
cCaveDefPoints Pts;
Pts.reserve(m_Points.size() * 2 + 1);
Pts.push_back(m_Points.front());
for (cCaveDefPoints::const_iterator itr = m_Points.begin() + 1, end = m_Points.end(); itr != end; ++itr)
{
int Random = a_Noise.IntNoise3DInt(PrevX, PrevY, PrevZ + i) / 11;
int len = (PrevX - itr->m_BlockX) * (PrevX - itr->m_BlockX);
len += (PrevY - itr->m_BlockY) * (PrevY - itr->m_BlockY);
len += (PrevZ - itr->m_BlockZ) * (PrevZ - itr->m_BlockZ);
len = 3 * (int)sqrt((double)len) / 4;
int Rad = std::min(MAX_RADIUS, std::max(MIN_RADIUS, (PrevR + itr->m_Radius) / 2 + (Random % 3) - 1));
Random /= 4;
int x = (itr->m_BlockX + PrevX) / 2 + (Random % (len + 1) - len / 2);
Random /= 256;
int y = (itr->m_BlockY + PrevY) / 2 + (Random % (len / 2 + 1) - len / 4);
Random /= 256;
int z = (itr->m_BlockZ + PrevZ) / 2 + (Random % (len + 1) - len / 2);
Pts.push_back(cCaveDefPoint(x, y, z, Rad));
Pts.push_back(*itr);
PrevX = itr->m_BlockX;
PrevY = itr->m_BlockY;
PrevZ = itr->m_BlockZ;
PrevR = itr->m_Radius;
}
std::swap(Pts, m_Points);
}
}
void cCaveTunnel::FinishLinear(void)
{
// For each segment, use Bresenham's 3D line algorithm to draw a "line" of defpoints
cCaveDefPoints Pts;
std::swap(Pts, m_Points);
m_Points.reserve(Pts.size() * 3);
cCaveDefPoint & PrevPoint = Pts.front();
int PrevX = PrevPoint.m_BlockX;
int PrevY = PrevPoint.m_BlockY;
int PrevZ = PrevPoint.m_BlockZ;
for (cCaveDefPoints::const_iterator itr = Pts.begin() + 1, end = Pts.end(); itr != end; ++itr)
{
int x1 = itr->m_BlockX;
int y1 = itr->m_BlockY;
int z1 = itr->m_BlockZ;
int dx = abs(x1 - PrevX);
int dy = abs(y1 - PrevY);
int dz = abs(z1 - PrevZ);
int sx = (PrevX < x1) ? 1 : -1;
int sy = (PrevY < y1) ? 1 : -1;
int sz = (PrevZ < z1) ? 1 : -1;
int R = itr->m_Radius;
if (dx >= std::max(dy, dz)) // x dominant
{
int yd = dy - dx / 2;
int zd = dz - dx / 2;
for (;;)
{
m_Points.push_back(cCaveDefPoint(PrevX, PrevY, PrevZ, R));
if (PrevX == x1)
{
break;
}
if (yd >= 0) // move along y
{
PrevY += sy;
yd -= dx;
}
if (zd >= 0) // move along z
{
PrevZ += sz;
zd -= dx;
}
// move along x
PrevX += sx;
yd += dy;
zd += dz;
}
}
else if (dy >= std::max(dx, dz)) // y dominant
{
int xd = dx - dy / 2;
int zd = dz - dy / 2;
for (;;)
{
m_Points.push_back(cCaveDefPoint(PrevX, PrevY, PrevZ, R));
if (PrevY == y1)
{
break;
}
if (xd >= 0) // move along x
{
PrevX += sx;
xd -= dy;
}
if (zd >= 0) // move along z
{
PrevZ += sz;
zd -= dy;
}
// move along y
PrevY += sy;
xd += dx;
zd += dz;
}
}
else
{
// z dominant
ASSERT(dz >= std::max(dx, dy));
int xd = dx - dz / 2;
int yd = dy - dz / 2;
for (;;)
{
m_Points.push_back(cCaveDefPoint(PrevX, PrevY, PrevZ, R));
if (PrevZ == z1)
{
break;
}
if (xd >= 0) // move along x
{
PrevX += sx;
xd -= dz;
}
if (yd >= 0) // move along y
{
PrevY += sy;
yd -= dz;
}
// move along z
PrevZ += sz;
xd += dx;
yd += dy;
}
} // if (which dimension is dominant)
} // for itr
}
