- v3s16 cpn = block->getPos() * MAP_BLOCKSIZE;
- cpn += v3s16(MAP_BLOCKSIZE / 2, MAP_BLOCKSIZE / 2, MAP_BLOCKSIZE / 2);
- float step = BS * 1;
- float stepfac = 1.1;
- float startoff = BS * 1;
- // The occlusion search of 'isOccluded()' must stop short of the target
- // point by distance 'endoff' (end offset) to not enter the target mapblock.
- // For the 8 mapblock corners 'endoff' must therefore be the maximum diagonal
- // of a mapblock, because we must consider all view angles.
- // sqrt(1^2 + 1^2 + 1^2) = 1.732
- float endoff = -BS * MAP_BLOCKSIZE * 1.732050807569;
- v3s16 spn = cam_pos_nodes;
- s16 bs2 = MAP_BLOCKSIZE / 2 + 1;
- // to reduce the likelihood of falsely occluded blocks
- // require at least two solid blocks
- // this is a HACK, we should think of a more precise algorithm
- u32 needed_count = 2;
- if (occlusion_culling_enabled &&
- // For the central point of the mapblock 'endoff' can be halved
- isOccluded(this, spn, cpn,
- step, stepfac, startoff, endoff / 2.0f, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(bs2,bs2,bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(bs2,bs2,-bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(bs2,-bs2,bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(bs2,-bs2,-bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(-bs2,bs2,bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(-bs2,bs2,-bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(-bs2,-bs2,bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef) &&
- isOccluded(this, spn, cpn + v3s16(-bs2,-bs2,-bs2),
- step, stepfac, startoff, endoff, needed_count, m_nodedef)) {