From ca6548c30a35f5be87e35037f63fe1371422bbf6 Mon Sep 17 00:00:00 2001 From: Jordan Date: Tue, 30 Jan 2018 21:03:35 +0000 Subject: [PATCH] Changed gradient idx table to match previous implementation, removed seeds from public API --- stb_perlin.h | 119 ++++++++++++++++++++++++++------------------------- 1 file changed, 61 insertions(+), 58 deletions(-) diff --git a/stb_perlin.h b/stb_perlin.h index 2d95dd6..14b6e4d 100644 --- a/stb_perlin.h +++ b/stb_perlin.h @@ -1,4 +1,4 @@ -// stb_perlin.h - v0.4 - perlin noise +// stb_perlin.h - v0.3 - perlin noise // public domain single-file C implementation by Sean Barrett // // LICENSE @@ -71,10 +71,10 @@ #ifdef __cplusplus extern "C" { #endif -extern float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, unsigned char seed); -extern float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float gain, float offset, int octaves, unsigned char seed); -extern float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float gain, int octaves, unsigned char seed); -extern float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves, unsigned char seed); +extern float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap); +extern float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float gain, float offset, int octaves); +extern float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float gain, int octaves); +extern float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves); #ifdef __cplusplus } #endif @@ -126,45 +126,46 @@ static unsigned char stb__perlin_randtab[512] = // perlin's gradient has 12 cases so some get used 1/16th of the time // and some 2/16ths. We reduce bias by changing those fractions -// to 21/256ths and 22/256ths +// to 5/64ths and 6/64ths -// same as array above but with value % 12 -static unsigned char stb__perlin_randtab_mod12[512] = +// this array is designed to match the previous implementation +// of gradient hash: indices[stb__perlin_randtab[i]&63] +static unsigned char stb__perlin_randtab_grad_idx[512] = { - 11, 5, 5, 4, 7, 9, 10, 1, 7, 5, 11, 1, 4, 6, 8, 3, - 8, 10, 1, 9, 3, 6, 1, 10, 0, 4, 4, 1, 9, 6, 11, 0, - 7, 3, 5, 6, 1, 4, 0, 3, 1, 8, 3, 6, 9, 8, 6, 0, - 8, 2, 0, 1, 1, 6, 5, 11, 9, 1, 3, 6, 2, 6, 11, 9, - 9, 4, 10, 1, 0, 2, 5, 0, 7, 6, 1, 0, 8, 2, 7, 5, - 10, 8, 4, 9, 2, 11, 9, 3, 3, 10, 10, 10, 11, 8, 6, 4, - 9, 2, 7, 6, 10, 11, 2, 10, 1, 7, 4, 10, 7, 2, 1, 3, - 5, 7, 10, 8, 1, 8, 7, 8, 8, 3, 4, 8, 4, 4, 7, 2, - 2, 8, 9, 7, 11, 9, 7, 4, 2, 5, 2, 3, 4, 6, 4, 4, - 10, 11, 0, 11, 8, 0, 6, 10, 0, 2, 3, 7, 3, 8, 4, 6, - 0, 0, 11, 0, 0, 6, 2, 1, 10, 2, 0, 1, 2, 4, 5, 3, - 7, 1, 5, 1, 1, 6, 5, 0, 7, 4, 5, 8, 9, 10, 9, 3, - 2, 11, 5, 6, 1, 9, 5, 11, 7, 8, 6, 2, 11, 10, 10, 5, - 11, 11, 7, 3, 6, 9, 11, 3, 0, 8, 5, 10, 9, 0, 2, 2, - 3, 3, 0, 2, 11, 8, 2, 0, 7, 9, 7, 5, 3, 9, 4, 3, - 1, 4, 11, 9, 6, 7, 10, 3, 5, 9, 11, 5, 0, 8, 10, 5, + 7, 9, 5, 0, 11, 1, 6, 9, 3, 9, 11, 1, 8, 10, 4, 7, + 8, 6, 1, 5, 3, 10, 9, 10, 0, 8, 4, 1, 5, 2, 7, 8, + 7, 11, 9, 10, 1, 0, 4, 7, 5, 0, 11, 6, 1, 4, 2, 8, + 8, 10, 4, 9, 9, 2, 5, 7, 9, 1, 7, 2, 2, 6, 11, 5, + 5, 4, 6, 9, 0, 1, 1, 0, 7, 6, 9, 8, 4, 10, 3, 1, + 2, 8, 8, 9, 10, 11, 5, 11, 11, 2, 6, 10, 3, 4, 2, 4, + 9, 10, 3, 2, 6, 3, 6, 10, 5, 3, 4, 10, 11, 2, 9, 11, + 1, 11, 10, 4, 9, 4, 11, 0, 4, 11, 4, 0, 0, 0, 7, 6, + 10, 4, 1, 3, 11, 5, 3, 4, 2, 9, 1, 3, 0, 1, 8, 0, + 6, 7, 8, 7, 0, 4, 6, 10, 8, 2, 3, 11, 11, 8, 0, 2, + 4, 8, 3, 0, 0, 10, 6, 1, 2, 2, 4, 5, 6, 0, 1, 3, + 11, 9, 5, 5, 9, 6, 9, 8, 3, 8, 1, 8, 9, 6, 9, 11, + 10, 7, 5, 6, 5, 9, 1, 3, 7, 0, 2, 10, 11, 2, 6, 1, + 3, 11, 7, 7, 2, 1, 7, 3, 0, 8, 1, 1, 5, 0, 6, 10, + 11, 11, 0, 2, 7, 0, 10, 8, 3, 5, 7, 1, 11, 1, 0, 7, + 9, 0, 11, 5, 10, 3, 2, 3, 5, 9, 7, 9, 8, 4, 6, 5, // and a second copy so we don't need an extra mask or static initializer - 11, 5, 5, 4, 7, 9, 10, 1, 7, 5, 11, 1, 4, 6, 8, 3, - 8, 10, 1, 9, 3, 6, 1, 10, 0, 4, 4, 1, 9, 6, 11, 0, - 7, 3, 5, 6, 1, 4, 0, 3, 1, 8, 3, 6, 9, 8, 6, 0, - 8, 2, 0, 1, 1, 6, 5, 11, 9, 1, 3, 6, 2, 6, 11, 9, - 9, 4, 10, 1, 0, 2, 5, 0, 7, 6, 1, 0, 8, 2, 7, 5, - 10, 8, 4, 9, 2, 11, 9, 3, 3, 10, 10, 10, 11, 8, 6, 4, - 9, 2, 7, 6, 10, 11, 2, 10, 1, 7, 4, 10, 7, 2, 1, 3, - 5, 7, 10, 8, 1, 8, 7, 8, 8, 3, 4, 8, 4, 4, 7, 2, - 2, 8, 9, 7, 11, 9, 7, 4, 2, 5, 2, 3, 4, 6, 4, 4, - 10, 11, 0, 11, 8, 0, 6, 10, 0, 2, 3, 7, 3, 8, 4, 6, - 0, 0, 11, 0, 0, 6, 2, 1, 10, 2, 0, 1, 2, 4, 5, 3, - 7, 1, 5, 1, 1, 6, 5, 0, 7, 4, 5, 8, 9, 10, 9, 3, - 2, 11, 5, 6, 1, 9, 5, 11, 7, 8, 6, 2, 11, 10, 10, 5, - 11, 11, 7, 3, 6, 9, 11, 3, 0, 8, 5, 10, 9, 0, 2, 2, - 3, 3, 0, 2, 11, 8, 2, 0, 7, 9, 7, 5, 3, 9, 4, 3, - 1, 4, 11, 9, 6, 7, 10, 3, 5, 9, 11, 5, 0, 8, 10, 5, + 7, 9, 5, 0, 11, 1, 6, 9, 3, 9, 11, 1, 8, 10, 4, 7, + 8, 6, 1, 5, 3, 10, 9, 10, 0, 8, 4, 1, 5, 2, 7, 8, + 7, 11, 9, 10, 1, 0, 4, 7, 5, 0, 11, 6, 1, 4, 2, 8, + 8, 10, 4, 9, 9, 2, 5, 7, 9, 1, 7, 2, 2, 6, 11, 5, + 5, 4, 6, 9, 0, 1, 1, 0, 7, 6, 9, 8, 4, 10, 3, 1, + 2, 8, 8, 9, 10, 11, 5, 11, 11, 2, 6, 10, 3, 4, 2, 4, + 9, 10, 3, 2, 6, 3, 6, 10, 5, 3, 4, 10, 11, 2, 9, 11, + 1, 11, 10, 4, 9, 4, 11, 0, 4, 11, 4, 0, 0, 0, 7, 6, + 10, 4, 1, 3, 11, 5, 3, 4, 2, 9, 1, 3, 0, 1, 8, 0, + 6, 7, 8, 7, 0, 4, 6, 10, 8, 2, 3, 11, 11, 8, 0, 2, + 4, 8, 3, 0, 0, 10, 6, 1, 2, 2, 4, 5, 6, 0, 1, 3, + 11, 9, 5, 5, 9, 6, 9, 8, 3, 8, 1, 8, 9, 6, 9, 11, + 10, 7, 5, 6, 5, 9, 1, 3, 7, 0, 2, 10, 11, 2, 6, 1, + 3, 11, 7, 7, 2, 1, 7, 3, 0, 8, 1, 1, 5, 0, 6, 10, + 11, 11, 0, 2, 7, 0, 10, 8, 3, 5, 7, 1, 11, 1, 0, 7, + 9, 0, 11, 5, 10, 3, 2, 3, 5, 9, 7, 9, 8, 4, 6, 5, }; static float stb__perlin_lerp(float a, float b, float t) @@ -201,7 +202,7 @@ static float stb__perlin_grad(int grad_idx, float x, float y, float z) return grad[0]*x + grad[1]*y + grad[2]*z; } -float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, unsigned char seed) +float stb_perlin_noise3_internal(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap, unsigned char seed) { float u,v,w; float n000,n001,n010,n011,n100,n101,n110,n111; @@ -233,14 +234,14 @@ float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z r10 = stb__perlin_randtab[r1+y0]; r11 = stb__perlin_randtab[r1+y1]; - n000 = stb__perlin_grad(stb__perlin_randtab_mod12[r00+z0], x , y , z ); - n001 = stb__perlin_grad(stb__perlin_randtab_mod12[r00+z1], x , y , z-1 ); - n010 = stb__perlin_grad(stb__perlin_randtab_mod12[r01+z0], x , y-1, z ); - n011 = stb__perlin_grad(stb__perlin_randtab_mod12[r01+z1], x , y-1, z-1 ); - n100 = stb__perlin_grad(stb__perlin_randtab_mod12[r10+z0], x-1, y , z ); - n101 = stb__perlin_grad(stb__perlin_randtab_mod12[r10+z1], x-1, y , z-1 ); - n110 = stb__perlin_grad(stb__perlin_randtab_mod12[r11+z0], x-1, y-1, z ); - n111 = stb__perlin_grad(stb__perlin_randtab_mod12[r11+z1], x-1, y-1, z-1 ); + n000 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r00+z0], x , y , z ); + n001 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r00+z1], x , y , z-1 ); + n010 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r01+z0], x , y-1, z ); + n011 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r01+z1], x , y-1, z-1 ); + n100 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r10+z0], x-1, y , z ); + n101 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r10+z1], x-1, y , z-1 ); + n110 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r11+z0], x-1, y-1, z ); + n111 = stb__perlin_grad(stb__perlin_randtab_grad_idx[r11+z1], x-1, y-1, z-1 ); n00 = stb__perlin_lerp(n000,n001,w); n01 = stb__perlin_lerp(n010,n011,w); @@ -253,7 +254,12 @@ float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z return stb__perlin_lerp(n0,n1,u); } -float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float gain, float offset, int octaves, unsigned char seed) +float stb_perlin_noise3(float x, float y, float z, int x_wrap, int y_wrap, int z_wrap) +{ + return stb_perlin_noise3_internal(x,y,z,x_wrap,y_wrap,z_wrap,0); +} + +float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float gain, float offset, int octaves) { int i; float frequency = 1.0f; @@ -262,19 +268,18 @@ float stb_perlin_ridge_noise3(float x, float y, float z, float lacunarity, float float sum = 0.0f; for (i = 0; i < octaves; i++) { - float r = stb_perlin_noise3(x*frequency,y*frequency,z*frequency,0,0,0,seed); + float r = stb_perlin_noise3_internal(x*frequency,y*frequency,z*frequency,0,0,0,(unsigned char)i); r = offset - fabs(r); r = r*r; sum += r*amplitude*prev; prev = r; frequency *= lacunarity; amplitude *= gain; - seed++; } return sum; } -float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float gain, int octaves, unsigned char seed) +float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float gain, int octaves) { int i; float frequency = 1.0f; @@ -282,15 +287,14 @@ float stb_perlin_fbm_noise3(float x, float y, float z, float lacunarity, float g float sum = 0.0f; for (i = 0; i < octaves; i++) { - sum += stb_perlin_noise3(x*frequency,y*frequency,z*frequency,0,0,0,seed)*amplitude; + sum += stb_perlin_noise3_internal(x*frequency,y*frequency,z*frequency,0,0,0,(unsigned char)i)*amplitude; frequency *= lacunarity; amplitude *= gain; - seed++; } return sum; } -float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves, unsigned char seed) +float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float gain, int octaves) { int i; float frequency = 1.0f; @@ -298,11 +302,10 @@ float stb_perlin_turbulence_noise3(float x, float y, float z, float lacunarity, float sum = 0.0f; for (i = 0; i < octaves; i++) { - float r = stb_perlin_noise3(x*frequency,y*frequency,z*frequency,0,0,0,seed)*amplitude; + float r = stb_perlin_noise3_internal(x*frequency,y*frequency,z*frequency,0,0,0,(unsigned char)i)*amplitude; sum += fabs(r); frequency *= lacunarity; amplitude *= gain; - seed++; } return sum; }