diff --git a/src/mapgen.cpp b/src/mapgen.cpp index 32f7e29eb..b5c48a471 100644 --- a/src/mapgen.cpp +++ b/src/mapgen.cpp @@ -213,27 +213,86 @@ void Mapgen::updateHeightmap(v3s16 nmin, v3s16 nmax) //printf("updateHeightmap: %dus\n", t.stop()); } +inline bool Mapgen::isLiquidHorizontallyFlowable(u32 vi, v3s16 em) +{ + u32 vi_neg_x = vi; + vm->m_area.add_x(em, vi_neg_x, -1); + if (vm->m_data[vi_neg_x].getContent() != CONTENT_IGNORE) { + const ContentFeatures &c_nx = ndef->get(vm->m_data[vi_neg_x]); + if (c_nx.floodable && !c_nx.isLiquid()) + return true; + } + u32 vi_pos_x = vi; + vm->m_area.add_x(em, vi_pos_x, +1); + if (vm->m_data[vi_pos_x].getContent() != CONTENT_IGNORE) { + const ContentFeatures &c_px = ndef->get(vm->m_data[vi_pos_x]); + if (c_px.floodable && !c_px.isLiquid()) + return true; + } + u32 vi_neg_z = vi; + vm->m_area.add_z(em, vi_neg_z, -1); + if (vm->m_data[vi_neg_z].getContent() != CONTENT_IGNORE) { + const ContentFeatures &c_nz = ndef->get(vm->m_data[vi_neg_z]); + if (c_nz.floodable && !c_nz.isLiquid()) + return true; + } + u32 vi_pos_z = vi; + vm->m_area.add_z(em, vi_pos_z, +1); + if (vm->m_data[vi_pos_z].getContent() != CONTENT_IGNORE) { + const ContentFeatures &c_pz = ndef->get(vm->m_data[vi_pos_z]); + if (c_pz.floodable && !c_pz.isLiquid()) + return true; + } + return false; +} void Mapgen::updateLiquid(UniqueQueue *trans_liquid, v3s16 nmin, v3s16 nmax) { - bool isliquid, wasliquid; + bool isignored, isliquid, wasignored, wasliquid, waschecked, waspushed; v3s16 em = vm->m_area.getExtent(); - for (s16 z = nmin.Z; z <= nmax.Z; z++) { - for (s16 x = nmin.X; x <= nmax.X; x++) { - wasliquid = true; + for (s16 z = nmin.Z + 1; z <= nmax.Z - 1; z++) + for (s16 x = nmin.X + 1; x <= nmax.X - 1; x++) { + wasignored = true; + wasliquid = false; + waschecked = false; + waspushed = false; - u32 i = vm->m_area.index(x, nmax.Y, z); - for (s16 y = nmax.Y; y >= nmin.Y; y--) { - isliquid = ndef->get(vm->m_data[i]).isLiquid(); + u32 vi = vm->m_area.index(x, nmax.Y, z); + for (s16 y = nmax.Y; y >= nmin.Y; y--) { + isignored = vm->m_data[vi].getContent() == CONTENT_IGNORE; + isliquid = ndef->get(vm->m_data[vi]).isLiquid(); - // there was a change between liquid and nonliquid, add to queue. - if (isliquid != wasliquid) + if (isignored || wasignored || isliquid == wasliquid) { + // Neither topmost node of liquid column nor topmost node below column + waschecked = false; + waspushed = false; + } else if (isliquid) { + // This is the topmost node in the column + bool ispushed = false; + if (isLiquidHorizontallyFlowable(vi, em)) { trans_liquid->push_back(v3s16(x, y, z)); - - wasliquid = isliquid; - vm->m_area.add_y(em, i, -1); + ispushed = true; + } + // Remember waschecked and waspushed to avoid repeated + // checks/pushes in case the column consists of only this node + waschecked = true; + waspushed = ispushed; + } else { + // This is the topmost node below a liquid column + u32 vi_above = vi; + vm->m_area.add_y(em, vi_above, 1); + if (!waspushed && (ndef->get(vm->m_data[vi]).floodable || + (!waschecked && isLiquidHorizontallyFlowable(vi_above, em)))) { + // Push back the lowest node in the column which is one + // node above this one + trans_liquid->push_back(v3s16(x, y + 1, z)); + } } + + wasliquid = isliquid; + wasignored = isignored; + vm->m_area.add_y(em, vi, -1); } } } diff --git a/src/mapgen.h b/src/mapgen.h index f673007b5..90ac84bd8 100644 --- a/src/mapgen.h +++ b/src/mapgen.h @@ -199,6 +199,10 @@ public: virtual int getSpawnLevelAtPoint(v2s16 p) { return 0; } private: + // isLiquidHorizontallyFlowable() is a helper function for updateLiquid() + // that checks whether there are floodable nodes without liquid beneath + // the node at index vi. + inline bool isLiquidHorizontallyFlowable(u32 vi, v3s16 em); DISABLE_CLASS_COPY(Mapgen); };