Mgvalleys: Add Dry Riverbeds
Lower water table where base humidity is low. Alter heat and humidity to compensate for river humidity and altitude chill. Correct misuse of surface_max_y in generateTerrain. Remove sand trails in the water at river mouths. Remove river water below water_level. Correct heat/humidity calculations where noises are less than zero. Correct heightmap errors as much as possible. Make humidity calculations more readable.
This commit is contained in:
Duane Robertson
paramat
parent
158bd76e87
commit
6969dd4224
|
|
@ -399,8 +399,21 @@ void MapgenValleys::calculateNoise()
|
|||
|
||||
//mapgen_profiler->avg("noisemaps", tcn.stop() / 1000.f);
|
||||
|
||||
float heat_offset = 0.f;
|
||||
float humidity_scale = 1.f;
|
||||
|
||||
// Altitude chill tends to reduce the average heat.
|
||||
if (use_altitude_chill)
|
||||
heat_offset = 5.f;
|
||||
|
||||
// River humidity tends to increase the humidity range.
|
||||
if (humid_rivers) {
|
||||
humidity_scale = 0.8f;
|
||||
}
|
||||
|
||||
for (s32 index = 0; index < csize.X * csize.Z; index++) {
|
||||
noise_heat->result[index] += noise_heat_blend->result[index];
|
||||
noise_heat->result[index] += noise_heat_blend->result[index] + heat_offset;
|
||||
noise_humidity->result[index] *= humidity_scale;
|
||||
noise_humidity->result[index] += noise_humidity_blend->result[index];
|
||||
}
|
||||
|
||||
|
|
@ -481,9 +494,10 @@ float MapgenValleys::terrainLevelFromNoise(TerrainNoise *tn)
|
|||
}
|
||||
|
||||
// base - depth : height of the bottom of the river
|
||||
// water_level - 6 : don't make rivers below 6 nodes under the surface
|
||||
// water_level - 3 : don't make rivers below 3 nodes under the surface
|
||||
// We use three because that's as low as the swamp biomes go.
|
||||
// There is no logical equivalent to this using rangelim.
|
||||
mount = MYMIN(MYMAX(base - depth, (float) (water_level - 6)), mount);
|
||||
mount = MYMIN(MYMAX(base - depth, (float)(water_level - 3)), mount);
|
||||
|
||||
// Slope has no influence on rivers.
|
||||
*tn->slope = 0.f;
|
||||
|
|
@ -503,7 +517,7 @@ float MapgenValleys::adjustedTerrainLevelFromNoise(TerrainNoise *tn)
|
|||
for (s16 y = y_start; y <= y_start + 1000; y++) {
|
||||
float fill = NoisePerlin3D(&noise_inter_valley_fill->np, tn->x, y, tn->z, seed);
|
||||
|
||||
if (fill * *tn->slope <= y - mount) {
|
||||
if (fill * *tn->slope < y - mount) {
|
||||
mount = MYMAX(y - 1, mount);
|
||||
break;
|
||||
}
|
||||
|
|
@ -552,6 +566,15 @@ float MapgenValleys::terrainLevelAtPoint(s16 x, s16 z)
|
|||
|
||||
int MapgenValleys::generateTerrain()
|
||||
{
|
||||
// Raising this reduces the rate of evaporation.
|
||||
static const float evaporation = 300.f;
|
||||
// from the lua
|
||||
static const float humidity_dropoff = 4.f;
|
||||
// constant to convert altitude chill (compatible with lua) to heat
|
||||
static const float alt_to_heat = 20.f;
|
||||
// humidity reduction by altitude
|
||||
static const float alt_to_humid = 10.f;
|
||||
|
||||
MapNode n_air(CONTENT_AIR);
|
||||
MapNode n_river_water(c_river_water_source);
|
||||
MapNode n_sand(c_sand);
|
||||
|
|
@ -564,42 +587,56 @@ int MapgenValleys::generateTerrain()
|
|||
|
||||
for (s16 z = node_min.Z; z <= node_max.Z; z++)
|
||||
for (s16 x = node_min.X; x <= node_max.X; x++, index_2d++) {
|
||||
s16 river_y = floor(noise_rivers->result[index_2d]);
|
||||
s16 surface_y = floor(noise_terrain_height->result[index_2d]);
|
||||
float river_y = noise_rivers->result[index_2d];
|
||||
float surface_y = noise_terrain_height->result[index_2d];
|
||||
float slope = noise_inter_valley_slope->result[index_2d];
|
||||
float t_heat = noise_heat->result[index_2d];
|
||||
|
||||
heightmap[index_2d] = surface_y;
|
||||
heightmap[index_2d] = -MAX_MAP_GENERATION_LIMIT;
|
||||
|
||||
if (surface_y > surface_max_y)
|
||||
surface_max_y = surface_y;
|
||||
surface_max_y = ceil(surface_y);
|
||||
|
||||
if (humid_rivers) {
|
||||
// Derive heat from (base) altitude. This will be most correct
|
||||
// at rivers, since other surface heights may vary below.
|
||||
if (use_altitude_chill && (surface_y > 0.f || river_y > 0.f))
|
||||
t_heat -= alt_to_heat * MYMAX(surface_y, river_y) / altitude_chill;
|
||||
|
||||
// If humidity is low or heat is high, lower the water table.
|
||||
float delta = noise_humidity->result[index_2d] - 50.f;
|
||||
if (delta < 0.f) {
|
||||
float t_evap = (t_heat - 32.f) / evaporation;
|
||||
river_y += delta * MYMAX(t_evap, 0.08f);
|
||||
}
|
||||
}
|
||||
|
||||
u32 index_3d = (z - node_min.Z) * zstride + (x - node_min.X);
|
||||
u32 index_data = vm->m_area.index(x, node_min.Y - 1, z);
|
||||
|
||||
// Mapgens concern themselves with stone and water.
|
||||
for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
|
||||
float fill = 0.f;
|
||||
fill = noise_inter_valley_fill->result[index_3d];
|
||||
|
||||
if (vm->m_data[index_data].getContent() == CONTENT_IGNORE) {
|
||||
bool river = (river_y > surface_y);
|
||||
float fill = noise_inter_valley_fill->result[index_3d];
|
||||
float surface_delta = (float)y - surface_y;
|
||||
bool river = y + 1 < river_y;
|
||||
|
||||
if (river && y == surface_y) {
|
||||
if (fabs(surface_delta) <= 0.5f && y > water_level && river) {
|
||||
// river bottom
|
||||
vm->m_data[index_data] = n_sand;
|
||||
} else if (river && y <= surface_y) {
|
||||
} else if (slope * fill > surface_delta) {
|
||||
// ground
|
||||
vm->m_data[index_data] = n_stone;
|
||||
} else if (river && y < river_y) {
|
||||
// river
|
||||
vm->m_data[index_data] = n_river_water;
|
||||
} else if ((!river) && myround(fill * slope) >= y - surface_y) {
|
||||
// ground
|
||||
vm->m_data[index_data] = n_stone;
|
||||
heightmap[index_2d] = surface_max_y = y;
|
||||
if (y > heightmap[index_2d])
|
||||
heightmap[index_2d] = y;
|
||||
if (y > surface_max_y)
|
||||
surface_max_y = y;
|
||||
} else if (y <= water_level) {
|
||||
// sea
|
||||
vm->m_data[index_data] = n_water;
|
||||
} else if (river) {
|
||||
// river
|
||||
vm->m_data[index_data] = n_river_water;
|
||||
} else {
|
||||
vm->m_data[index_data] = n_air;
|
||||
}
|
||||
|
|
@ -609,18 +646,51 @@ int MapgenValleys::generateTerrain()
|
|||
index_3d += ystride;
|
||||
}
|
||||
|
||||
// Although the original valleys adjusts humidity by distance
|
||||
// from seawater, this causes problems with the default biomes.
|
||||
// Adjust only by freshwater proximity.
|
||||
const float humidity_offset = 0.8f; // derived by testing
|
||||
if (humid_rivers)
|
||||
noise_humidity->result[index_2d] *= (1 + pow(0.5f, MYMAX((surface_max_y
|
||||
- noise_rivers->result[index_2d]) / 3.f, 0.f))) * humidity_offset;
|
||||
// This happens if we're generating a chunk that doesn't
|
||||
// contain the terrain surface, in which case, we need
|
||||
// to set heightmap to a value outside of the chunk,
|
||||
// to avoid confusing lua mods that use heightmap.
|
||||
if (heightmap[index_2d] == -MAX_MAP_GENERATION_LIMIT) {
|
||||
s16 surface_y_int = myround(surface_y);
|
||||
if (surface_y_int > node_max.Y + 1 || surface_y_int < node_min.Y - 1) {
|
||||
// If surface_y is outside the chunk, it's good enough.
|
||||
heightmap[index_2d] = surface_y_int;
|
||||
} else {
|
||||
// If the ground is outside of this chunk, but surface_y
|
||||
// is within the chunk, give a value outside.
|
||||
heightmap[index_2d] = node_min.Y - 2;
|
||||
}
|
||||
}
|
||||
|
||||
// Assign the heat adjusted by altitude.
|
||||
if (use_altitude_chill && surface_max_y > 0)
|
||||
noise_heat->result[index_2d] *=
|
||||
pow(0.5f, (surface_max_y - altitude_chill / 3.f) / altitude_chill);
|
||||
if (humid_rivers) {
|
||||
// Use base ground (water table) in a riverbed, to
|
||||
// avoid an unnatural rise in humidity.
|
||||
float t_alt = MYMAX(noise_rivers->result[index_2d], (float)heightmap[index_2d]);
|
||||
float humid = noise_humidity->result[index_2d];
|
||||
float water_depth = (t_alt - river_y) / humidity_dropoff;
|
||||
humid *= 1.f + pow(0.5f, MYMAX(water_depth, 1.f));
|
||||
|
||||
// Reduce humidity with altitude (ignoring riverbeds).
|
||||
// This is similar to the lua version's seawater adjustment,
|
||||
// but doesn't increase the base humidity, which causes
|
||||
// problems with the default biomes.
|
||||
if (t_alt > 0.f)
|
||||
humid -= alt_to_humid * t_alt / altitude_chill;
|
||||
|
||||
noise_humidity->result[index_2d] = humid;
|
||||
}
|
||||
|
||||
// Assign the heat adjusted by any changed altitudes.
|
||||
// The altitude will change about half the time.
|
||||
if (use_altitude_chill) {
|
||||
// ground height ignoring riverbeds
|
||||
float t_alt = MYMAX(noise_rivers->result[index_2d], (float)heightmap[index_2d]);
|
||||
if (humid_rivers && heightmap[index_2d] == (s16)myround(surface_y))
|
||||
// The altitude hasn't changed. Use the first result.
|
||||
noise_heat->result[index_2d] = t_heat;
|
||||
else if (t_alt > 0.f)
|
||||
noise_heat->result[index_2d] -= alt_to_heat * t_alt / altitude_chill;
|
||||
}
|
||||
}
|
||||
|
||||
return surface_max_y;
|
||||
|
|
@ -645,7 +715,7 @@ MgStoneType MapgenValleys::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);
|
||||
bool water_above = (c_above == c_water_source || c_above == c_river_water_source);
|
||||
|
||||
// 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.
|
||||
|
|
@ -714,7 +784,7 @@ MgStoneType MapgenValleys::generateBiomes(float *heat_map, float *humidity_map)
|
|||
water_above = true;
|
||||
} else if (c == c_river_water_source) {
|
||||
vm->m_data[vi] = MapNode(biome->c_river_water);
|
||||
nplaced = U16_MAX; // Sand was already placed under rivers.
|
||||
nplaced = depth_top; // Enable filler placement for next surface
|
||||
air_above = false;
|
||||
water_above = true;
|
||||
} else if (c == CONTENT_AIR) {
|
||||
|
|
|
|||
Loading…
Reference in New Issue