diff options
Diffstat (limited to 'src/mapgen_fractal.cpp')
| -rw-r--r-- | src/mapgen_fractal.cpp | 86 |
1 files changed, 72 insertions, 14 deletions
diff --git a/src/mapgen_fractal.cpp b/src/mapgen_fractal.cpp index 14dfe5c85..6c03c4ca9 100644 --- a/src/mapgen_fractal.cpp +++ b/src/mapgen_fractal.cpp @@ -66,7 +66,7 @@ MapgenFractal::MapgenFractal(int mapgenid, MapgenParams *params, EmergeManager * MapgenFractalParams *sp = (MapgenFractalParams *)params->sparams; this->spflags = sp->spflags; - this->formula = sp->formula; + this->fractal = sp->fractal; this->iterations = sp->iterations; this->scale = sp->scale; this->offset = sp->offset; @@ -77,6 +77,9 @@ MapgenFractal::MapgenFractal(int mapgenid, MapgenParams *params, EmergeManager * this->julia_z = sp->julia_z; this->julia_w = sp->julia_w; + this->formula = fractal / 2 + fractal % 2; + this->julia = fractal % 2 == 0; + //// 2D terrain noise noise_seabed = new Noise(&sp->np_seabed, seed, csize.X, csize.Z); noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z); @@ -141,7 +144,7 @@ MapgenFractalParams::MapgenFractalParams() { spflags = 0; - formula = 1; + fractal = 1; iterations = 11; scale = v3f(4096.0, 1024.0, 4096.0); offset = v3f(1.79, 0.0, 0.0); @@ -163,7 +166,7 @@ void MapgenFractalParams::readParams(const Settings *settings) { settings->getFlagStrNoEx("mgfractal_spflags", spflags, flagdesc_mapgen_fractal); - settings->getU16NoEx("mgfractal_formula", formula); + settings->getU16NoEx("mgfractal_fractal", fractal); settings->getU16NoEx("mgfractal_iterations", iterations); settings->getV3FNoEx("mgfractal_scale", scale); settings->getV3FNoEx("mgfractal_offset", offset); @@ -185,7 +188,7 @@ void MapgenFractalParams::writeParams(Settings *settings) const { settings->setFlagStr("mgfractal_spflags", spflags, flagdesc_mapgen_fractal, U32_MAX); - settings->setU16("mgfractal_formula", formula); + settings->setU16("mgfractal_fractal", fractal); settings->setU16("mgfractal_iterations", iterations); settings->setV3F("mgfractal_scale", scale); settings->setV3F("mgfractal_offset", offset); @@ -368,7 +371,7 @@ bool MapgenFractal::getFractalAtPoint(s16 x, s16 y, s16 z) { float cx, cy, cz, cw, ox, oy, oz, ow; - if (formula % 2 == 0) { // Julia sets, formula = 2, 4, 6, 8 + if (julia) { // Julia set cx = julia_x; cy = julia_y; cz = julia_z; @@ -377,7 +380,7 @@ bool MapgenFractal::getFractalAtPoint(s16 x, s16 y, s16 z) oy = (float)y / scale.Y - offset.Y; oz = (float)z / scale.Z - offset.Z; ow = slice_w; - } else { // Mandelbrot sets, formula = 1, 3, 5, 7 + } else { // Mandelbrot set cx = (float)x / scale.X - offset.X; cy = (float)y / scale.Y - offset.Y; cz = (float)z / scale.Z - offset.Z; @@ -388,32 +391,87 @@ bool MapgenFractal::getFractalAtPoint(s16 x, s16 y, s16 z) ow = 0.0f; } + float nx = 0.0f; + float ny = 0.0f; + float nz = 0.0f; + float nw = 0.0f; + for (u16 iter = 0; iter < iterations; iter++) { - float nx = 0.0f; - float ny = 0.0f; - float nz = 0.0f; - float nw = 0.0f; - if (formula == 1 || formula == 2) { // 4D "Roundy" Mandelbrot/Julia Set + if (formula == 1) { // 4D "Roundy" nx = ox * ox - oy * oy - oz * oz - ow * ow + cx; ny = 2.0f * (ox * oy + oz * ow) + cy; nz = 2.0f * (ox * oz + oy * ow) + cz; nw = 2.0f * (ox * ow + oy * oz) + cw; - } else if (formula == 3 || formula == 4) { // 4D "Squarry" Mandelbrot/Julia Set + } else if (formula == 2) { // 4D "Squarry" nx = ox * ox - oy * oy - oz * oz - ow * ow + cx; ny = 2.0f * (ox * oy + oz * ow) + cy; nz = 2.0f * (ox * oz + oy * ow) + cz; nw = 2.0f * (ox * ow - oy * oz) + cw; - } else if (formula == 5 || formula == 6) { // 4D "Mandy Cousin" Mandelbrot/Julia Set + } else if (formula == 3) { // 4D "Mandy Cousin" nx = ox * ox - oy * oy - oz * oz + ow * ow + cx; ny = 2.0f * (ox * oy + oz * ow) + cy; nz = 2.0f * (ox * oz + oy * ow) + cz; nw = 2.0f * (ox * ow + oy * oz) + cw; - } else if (formula == 7 || formula == 8) { // 4D "Variation" Mandelbrot/Julia Set + } else if (formula == 4) { // 4D "Variation" nx = ox * ox - oy * oy - oz * oz - ow * ow + cx; ny = 2.0f * (ox * oy + oz * ow) + cy; nz = 2.0f * (ox * oz - oy * ow) + cz; nw = 2.0f * (ox * ow + oy * oz) + cw; + } else if (formula == 5) { // 3D "Mandelbrot/Mandelbar" + nx = ox * ox - oy * oy - oz * oz + cx; + ny = 2.0f * ox * oy + cy; + nz = -2.0f * ox * oz + cz; + } else if (formula == 6) { // 3D "Christmas Tree" + // Altering the formula here is necessary to avoid division by zero + if (fabs(oz) < 0.000000001f) { + nx = ox * ox - oy * oy - oz * oz + cx; + ny = 2.0f * oy * ox + cy; + nz = 4.0f * oz * ox + cz; + } else { + float a = (2.0f * ox) / (sqrt(oy * oy + oz * oz)); + nx = ox * ox - oy * oy - oz * oz + cx; + ny = a * (oy * oy - oz * oz) + cy; + nz = a * 2.0f * oy * oz + cz; + } + } else if (formula == 7) { // 3D "Mandelbulb" + if (fabs(oy) < 0.000000001f) { + nx = ox * ox - oz * oz + cx; + ny = cy; + nz = -2.0f * oz * sqrt(ox * ox) + cz; + } else { + float a = 1.0f - (oz * oz) / (ox * ox + oy * oy); + nx = (ox * ox - oy * oy) * a + cx; + ny = 2.0f * ox * oy * a + cy; + nz = -2.0f * oz * sqrt(ox * ox + oy * oy) + cz; + } + } else if (formula == 8) { // 3D "Cosine Mandelbulb" + if (fabs(oy) < 0.000000001f) { + nx = 2.0f * ox * oz + cx; + ny = 4.0f * oy * oz + cy; + nz = oz * oz - ox * ox - oy * oy + cz; + } else { + float a = (2.0f * oz) / sqrt(ox * ox + oy * oy); + nx = (ox * ox - oy * oy) * a + cx; + ny = 2.0f * ox * oy * a + cy; + nz = oz * oz - ox * ox - oy * oy + cz; + } + } else if (formula == 9) { // 4D "Mandelbulb" + float rxy = sqrt(ox * ox + oy * oy); + float rxyz = sqrt(ox * ox + oy * oy + oz * oz); + if (fabs(ow) < 0.000000001f && fabs(oz) < 0.000000001f) { + nx = (ox * ox - oy * oy) + cx; + ny = 2.0f * ox * oy + cy; + nz = -2.0f * rxy * oz + cz; + nw = 2.0f * rxyz * ow + cw; + } else { + float a = 1.0f - (ow * ow) / (rxyz * rxyz); + float b = a * (1.0f - (oz * oz) / (rxy * rxy)); + nx = (ox * ox - oy * oy) * b + cx; + ny = 2.0f * ox * oy * b + cy; + nz = -2.0f * rxy * oz * a + cz; + nw = 2.0f * rxyz * ow + cw; + } } if (nx * nx + ny * ny + nz * nz + nw * nw > 4.0f) |