Mgv5/mgv7: Trigger biome recalculation at underwater surfaces

diff --git a/src/mapgen_v5.cpp b/src/mapgen_v5.cpp
index abea2f7142ce3b693927e2d5000056b5fd78e203..7c2a149fbc076583b6436e7b91d446b469bf43d8 100644 (file)
--- a/src/mapgen_v5.cpp
+++ b/src/mapgen_v5.cpp
@@ -415,21 +415,24 @@ MgStoneType MapgenV5::generateBiomes(float *heat_map, float *humidity_map)
                // generated mapchunk or if not, a node of overgenerated base terrain.
                content_t c_above = vm->m_data[vi + em.X].getContent();
                bool air_above = c_above == CONTENT_AIR;
+               bool water_above = c_above == c_water_source;
 
-               // If there is air above enable top/filler placement, otherwise force nplaced to
-               // stone level by setting a number that will exceed any possible filler depth.
-               u16 nplaced = (air_above) ? 0 : (u16)-1;
+               // If there is air or water above enable top/filler placement, otherwise force
+               // nplaced to stone level by setting a number exceeding any possible filler depth.
+               u16 nplaced = (air_above || water_above) ? 0 : (u16)-1;
 
                for (s16 y = node_max.Y; y >= node_min.Y; y--) {
                        content_t c = vm->m_data[vi].getContent();
 
-                       // Biome is only (re)calculated for each stone/water upper surface found
-                       // below air while working downwards. The chosen biome then remains in
-                       // effect for all nodes below until the next biome recalculation.
-                       // Biome is (re)calculated when a stone/water node is either: detected
-                       // below an air node, or, is at column top and might be underground
-                       // or underwater and therefore might not be below air.
-                       if (c != CONTENT_AIR && (y == node_max.Y || air_above)) {
+                       // Biome is recalculated each time an upper surface is detected while
+                       // working down a column. The selected biome then remains in effect for
+                       // all nodes below until the next surface and biome recalculation.
+                       // Biome is recalculated:
+                       // 1. At the surface of stone below air or water.
+                       // 2. At the surface of water below air.
+                       // 3. When stone or water is detected but biome has not yet been calculated.
+                       if ((c == c_stone && (air_above || water_above || !biome)) ||
+                                       (c == c_water_source && (air_above || !biome))) {
                                biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
                                depth_top = biome->depth_top;
                                base_filler = MYMAX(depth_top + biome->depth_filler
@@ -466,17 +469,21 @@ MgStoneType MapgenV5::generateBiomes(float *heat_map, float *humidity_map)
                                }
 
                                air_above = false;
+                               water_above = false;
                        } else if (c == c_water_source) {
                                vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
                                                biome->c_water_top : biome->c_water);
                                nplaced = 0;  // Enable top/filler placement for next surface
-                               air_above = false;  // Biome is not recalculated underwater
+                               air_above = false;
+                               water_above = true;
                        } else if (c == CONTENT_AIR) {
                                nplaced = 0;  // Enable top/filler placement for next surface
-                               air_above = true;  // Biome will be recalculated at next surface
+                               air_above = true;
+                               water_above = false;
                        } else {  // Possible various nodes overgenerated from neighbouring mapchunks
                                nplaced = (u16)-1;  // Disable top/filler placement
                                air_above = false;
+                               water_above = false;
                        }
 
                        vm->m_area.add_y(em, vi, -1);

diff --git a/src/mapgen_v7.cpp b/src/mapgen_v7.cpp
index 41e35cb00ae95c3a6d8919c2bfa67d0f3c0db42e..be7212e0e0d40c21ebf5fc28be6a24057e87a521 100644 (file)
--- a/src/mapgen_v7.cpp
+++ b/src/mapgen_v7.cpp
@@ -610,21 +610,24 @@ MgStoneType MapgenV7::generateBiomes(float *heat_map, float *humidity_map)
                // generated mapchunk or if not, a node of overgenerated base terrain.
                content_t c_above = vm->m_data[vi + em.X].getContent();
                bool air_above = c_above == CONTENT_AIR;
+               bool water_above = c_above == c_water_source;
 
-               // If there is air above enable top/filler placement, otherwise force nplaced to
-               // stone level by setting a number that will exceed any possible filler depth.
-               u16 nplaced = (air_above) ? 0 : (u16)-1;
+               // If there is air or water above enable top/filler placement, otherwise force
+               // nplaced to stone level by setting a number exceeding any possible filler depth.
+               u16 nplaced = (air_above || water_above) ? 0 : (u16)-1;
 
                for (s16 y = node_max.Y; y >= node_min.Y; y--) {
                        content_t c = vm->m_data[vi].getContent();
 
-                       // Biome is only (re)calculated for each stone/water upper surface found
-                       // below air while working downwards. The chosen biome then remains in
-                       // effect for all nodes below until the next biome recalculation.
-                       // Biome is (re)calculated when a stone/water node is either: detected
-                       // below an air node, or, is at column top and might be underground
-                       // or underwater and therefore might not be below air.
-                       if (c != CONTENT_AIR && (y == node_max.Y || air_above)) {
+                       // Biome is recalculated each time an upper surface is detected while
+                       // working down a column. The selected biome then remains in effect for
+                       // all nodes below until the next surface and biome recalculation.
+                       // Biome is recalculated:
+                       // 1. At the surface of stone below air or water.
+                       // 2. At the surface of water below air.
+                       // 3. When stone or water is detected but biome has not yet been calculated.
+                       if ((c == c_stone && (air_above || water_above || !biome)) ||
+                                       (c == c_water_source && (air_above || !biome))) {
                                biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
                                depth_top = biome->depth_top;
                                base_filler = MYMAX(depth_top + biome->depth_filler
@@ -661,17 +664,21 @@ MgStoneType MapgenV7::generateBiomes(float *heat_map, float *humidity_map)
                                }
 
                                air_above = false;
+                               water_above = false;
                        } else if (c == c_water_source) {
                                vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
                                                biome->c_water_top : biome->c_water);
                                nplaced = 0;  // Enable top/filler placement for next surface
-                               air_above = false;  // Biome is not recalculated underwater
+                               air_above = false;
+                               water_above = true;
                        } else if (c == CONTENT_AIR) {
                                nplaced = 0;  // Enable top/filler placement for next surface
-                               air_above = true;  // Biome will be recalculated at next surface
+                               air_above = true;
+                               water_above = false;
                        } else {  // Possible various nodes overgenerated from neighbouring mapchunks
                                nplaced = (u16)-1;  // Disable top/filler placement
                                air_above = false;
+                               water_above = false;
                        }
 
                        vm->m_area.add_y(em, vi, -1);