X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Fnoise.h;h=d2287835ea9966dd618602c683e782e1f186cef1;hb=3444dec2db30b8aa8a4e9c268fdba2f84b870ce3;hp=1f7bdbbf46e025ceb8943a5c5073898945d0a103;hpb=2fd3d5202051e03303ac2b8e76976a7c4c8477f3;p=minetest.git diff --git a/src/noise.h b/src/noise.h index 1f7bdbbf4..d2287835e 100644 --- a/src/noise.h +++ b/src/noise.h @@ -32,43 +32,65 @@ extern FlagDesc flagdesc_noiseparams[]; -class PseudoRandom -{ +// Note: this class is not polymorphic so that its high level of +// optimizability may be preserved in the common use case +class PseudoRandom { public: - PseudoRandom(): m_next(0) - { - } - PseudoRandom(int seed): m_next(seed) + const static u32 RANDOM_RANGE = 32767; + + inline PseudoRandom(int seed=0): + m_next(seed) { } - void seed(int seed) + + inline void seed(int seed) { m_next = seed; } - // Returns 0...32767 - int next() + + inline int next() { m_next = m_next * 1103515245 + 12345; - return((unsigned)(m_next/65536) % 32768); + return (unsigned)(m_next / 65536) % (RANDOM_RANGE + 1); } - int range(int min, int max) + + inline int range(int min, int max) { - if(max-min > 32768/10) - { - //dstream<<"WARNING: PseudoRandom::range: max > 32767"< max) - { - assert(0); - return max; - } - return (next()%(max-min+1))+min; + assert(max >= min); + /* + Here, we ensure the range is not too large relative to RANDOM_MAX, + as otherwise the effects of bias would become noticable. Unlike + PcgRandom, we cannot modify this RNG's range as it would change the + output of this RNG for reverse compatibility. + */ + assert((u32)(max - min) <= (RANDOM_RANGE + 1) / 10); + + return (next() % (max - min + 1)) + min; } + private: int m_next; }; +class PcgRandom { +public: + const static s32 RANDOM_MIN = -0x7fffffff - 1; + const static s32 RANDOM_MAX = 0x7fffffff; + const static u32 RANDOM_RANGE = 0xffffffff; + + PcgRandom(u64 state=0x853c49e6748fea9bULL, u64 seq=0xda3e39cb94b95bdbULL); + void seed(u64 state, u64 seq=0xda3e39cb94b95bdbULL); + u32 next(); + u32 range(u32 bound); + s32 range(s32 min, s32 max); + void bytes(void *out, size_t len); + s32 randNormalDist(s32 min, s32 max, int num_trials=6); + +private: + u64 m_state; + u64 m_inc; +}; + #define NOISE_FLAG_DEFAULTS 0x01 #define NOISE_FLAG_EASED 0x02 #define NOISE_FLAG_ABSVALUE 0x04 @@ -87,7 +109,8 @@ struct NoiseParams { float lacunarity; u32 flags; - NoiseParams() { + NoiseParams() + { offset = 0.0f; scale = 1.0f; spread = v3f(250, 250, 250); @@ -122,13 +145,14 @@ struct NoiseParams { class Noise { public: - NoiseParams *np; + NoiseParams np; int seed; int sx; int sy; int sz; - float *noisebuf; - float *buf; + float *noise_buf; + float *gradient_buf; + float *persist_buf; float *result; Noise(NoiseParams *np, int seed, int sx, int sy, int sz=1); @@ -137,7 +161,6 @@ class Noise { void setSize(int sx, int sy, int sz=1); void setSpreadFactor(v3f spread); void setOctaves(int octaves); - void resizeNoiseBuf(bool is3d); void gradientMap2D( float x, float y, @@ -151,10 +174,54 @@ class Noise { float *perlinMap2D(float x, float y, float *persistence_map=NULL); float *perlinMap3D(float x, float y, float z, float *persistence_map=NULL); + inline float *perlinMap2D_PO(float x, float xoff, float y, float yoff, + float *persistence_map=NULL) + { + return perlinMap2D( + x + xoff * np.spread.X, + y + yoff * np.spread.Y, + persistence_map); + } + + inline float *perlinMap3D_PO(float x, float xoff, float y, float yoff, + float z, float zoff, float *persistence_map=NULL) + { + return perlinMap3D( + x + xoff * np.spread.X, + y + yoff * np.spread.Y, + z + zoff * np.spread.Z, + persistence_map); + } + +private: + void allocBuffers(); + void resizeNoiseBuf(bool is3d); void updateResults(float g, float *gmap, float *persistence_map, size_t bufsize); - void transformNoiseMap(); + }; +float NoisePerlin2D(NoiseParams *np, float x, float y, int seed); +float NoisePerlin3D(NoiseParams *np, float x, float y, float z, int seed); + +inline float NoisePerlin2D_PO(NoiseParams *np, float x, float xoff, + float y, float yoff, int seed) +{ + return NoisePerlin2D(np, + x + xoff * np->spread.X, + y + yoff * np->spread.Y, + seed); +} + +inline float NoisePerlin3D_PO(NoiseParams *np, float x, float xoff, + float y, float yoff, float z, float zoff, int seed) +{ + return NoisePerlin3D(np, + x + xoff * np->spread.X, + y + yoff * np->spread.Y, + z + zoff * np->spread.Z, + seed); +} + // Return value: -1 ... 1 float noise2d(int x, int y, int seed); float noise3d(int x, int y, int z, int seed); @@ -174,44 +241,12 @@ float noise3d_perlin(float x, float y, float z, int seed, float noise3d_perlin_abs(float x, float y, float z, int seed, int octaves, float persistence, bool eased=false); -inline float easeCurve(float t) { +inline float easeCurve(float t) +{ return t * t * t * (t * (6.f * t - 15.f) + 10.f); } float contour(float v); -#define NoisePerlin2D(np, x, y, s) \ - ((np)->offset + (np)->scale * noise2d_perlin( \ - (float)(x) / (np)->spread.X, \ - (float)(y) / (np)->spread.Y, \ - (s) + (np)->seed, (np)->octaves, (np)->persist)) - -#define NoisePerlin2DNoTxfm(np, x, y, s) \ - (noise2d_perlin( \ - (float)(x) / (np)->spread.X, \ - (float)(y) / (np)->spread.Y, \ - (s) + (np)->seed, (np)->octaves, (np)->persist)) - -#define NoisePerlin2DPosOffset(np, x, xoff, y, yoff, s) \ - ((np)->offset + (np)->scale * noise2d_perlin( \ - (float)(xoff) + (float)(x) / (np)->spread.X, \ - (float)(yoff) + (float)(y) / (np)->spread.Y, \ - (s) + (np)->seed, (np)->octaves, (np)->persist)) - -#define NoisePerlin2DNoTxfmPosOffset(np, x, xoff, y, yoff, s) \ - (noise2d_perlin( \ - (float)(xoff) + (float)(x) / (np)->spread.X, \ - (float)(yoff) + (float)(y) / (np)->spread.Y, \ - (s) + (np)->seed, (np)->octaves, (np)->persist)) - -#define NoisePerlin3D(np, x, y, z, s) ((np)->offset + (np)->scale * \ - noise3d_perlin((float)(x) / (np)->spread.X, (float)(y) / (np)->spread.Y, \ - (float)(z) / (np)->spread.Z, (s) + (np)->seed, (np)->octaves, (np)->persist)) - -#define NoisePerlin3DEased(np, x, y, z, s) ((np)->offset + (np)->scale * \ - noise3d_perlin((float)(x) / (np)->spread.X, (float)(y) / (np)->spread.Y, \ - (float)(z) / (np)->spread.Z, (s) + (np)->seed, (np)->octaves, \ - (np)->persist, true)) - #endif