diff options
| -rw-r--r-- | fog.cginc | 50 |
1 files changed, 35 insertions, 15 deletions
@@ -21,15 +21,7 @@ struct Fog00PBR { float depth; }; -#define FOG_PERLIN_NOISE_MODE 1 - -#if FOG_PERLIN_NOISE_MODE == 0 -#define FOG_PERLIN_NOISE perlin_noise_3d -#define FOG_PERLIN_NOISE_SCALE 1 -#else -#define FOG_PERLIN_NOISE perlin_noise_3d_tex #define FOG_PERLIN_NOISE_SCALE 32 -#endif float perlin_noise_3d_tex(float3 p) { @@ -37,12 +29,46 @@ float perlin_noise_3d_tex(float3 p) return _Gimmick_Fog_00_Noise.SampleLevel(trilinear_repeat_s, p.xyz * 0.00390625, 0); } +#define FBM_OCTAVES 4 + +float perlin_noise_3d_tex_fbm(float3 p) +{ + float res = perlin_noise_3d_tex(p); + float p_scale = 1; + float d_scale = .6666; + for (uint i = 1; i < FBM_OCTAVES; i++) { + p_scale *= 2; + d_scale *= .5; + res += perlin_noise_3d_tex(p*p_scale)*d_scale; + } + return res; +} + float3 perlin_noise_3d_tex_normal(float3 p) { // 1/256 = 0.00390625 return _Gimmick_Fog_00_Noise_Normals.SampleLevel(trilinear_repeat_s, p.xyz * 0.00390625, 0) * 2 - 1; } +float3 perlin_noise_3d_tex_normal_fbm(float3 p) +{ + float3 res = perlin_noise_3d_tex_normal(p); + float p_scale = 1; + float d_scale = .6666; + for (uint i = 1; i < FBM_OCTAVES; i++) { + p_scale *= 2; + d_scale *= .5; + res += perlin_noise_3d_tex_normal(p*p_scale)*d_scale; + } + return res; +} + +// idea from here https://iquilezles.org/articles/warp/ +float perlin_noise_3d_tex_warp(float3 p) +{ + return perlin_noise_3d_tex_fbm(p + perlin_noise_3d_tex(p) * 500); +} + float3 light_fog00( float3 albedo, float NoL, @@ -66,14 +92,8 @@ float map(float3 p, out float3 normal) { float radius2 = clamp(_Gimmick_Fog_00_Radius * _Gimmick_Fog_00_Radius - dot(p, p), 0, RADIUS_TRANS_WIDTH) * RADIUS_TRANS_WIDTH_RCP; float3 pp = p * _Gimmick_Fog_00_Noise_Scale * FOG_PERLIN_NOISE_SCALE; - float density = FOG_PERLIN_NOISE(pp+t) * radius2 * 0.7; + float density = perlin_noise_3d_tex_warp(pp+t) * radius2; normal = perlin_noise_3d_tex_normal(pp+t) * density; - // Add higher octave to create more visual interest -#if 1 - float cur_density = FOG_PERLIN_NOISE(pp*3+t*1.5) * radius2 * 0.3; - density += cur_density; - normal += perlin_noise_3d_tex_normal(pp*3+t*1.5) * cur_density; -#endif normal = normalize(normal); return saturate(density); |