paysages : Progress on bruneton atmospheric model.
git-svn-id: https://subversion.assembla.com/svn/thunderk/paysages@477 b1fd45b6-86a6-48da-8261-f70d1f35bdcc
This commit is contained in:
ThunderK
parent
f82b0f1e02
commit
983270ee56
3 changed files with 302 additions and 65 deletions
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@ -5,9 +5,11 @@
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* http://evasion.inrialpes.fr/~Eric.Bruneton/
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*/
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#if 0
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#if 1
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#include <math.h>
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#include <stdlib.h>
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#include "../system.h"
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#define TRANSMITTANCE_NON_LINEAR
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#define INSCATTER_NON_LINEAR
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@ -19,6 +21,12 @@ static const double RL = 6421.0;
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static const double exposure = 0.4;
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static const float ISun = 100.0;
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#define RES_MU 128
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#define RES_MU_S 32
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#define RES_R 32
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#define RES_NU 8
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#define TRANSMITTANCE_INTEGRAL_SAMPLES 500
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// Rayleigh
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static const double HR = 8.0;
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static const Color betaR = {5.8e-3, 1.35e-2, 3.31e-2, 1.0};
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@ -26,8 +34,8 @@ static const Color betaR = {5.8e-3, 1.35e-2, 3.31e-2, 1.0};
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// Mie
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// DEFAULT
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static const double HM = 1.2;
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/*static const vec3 betaMSca = vec3(4e-3);
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static const vec3 betaMEx = betaMSca / 0.9;*/
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static const Vector3 betaMSca = {4e-3, 4e-3, 4e-3};
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static const Vector3 betaMEx = {4e-3 / 0.9, 4e-3 / 0.9, 4e-3 / 0.9};
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static const double mieG = 0.8;
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// CLEAR SKY
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/*static const float HM = 1.2;
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@ -42,7 +50,79 @@ static const float mieG = 0.65;*/
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#define step(_a_,_b_) ((_a_) < (_b_) ? 0 : 1)
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#define max(_a_,_b_) ((_a_) < (_b_) ? (_a_) : (_b_))
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#define min(_a_,_b_) ((_a_) > (_b_) ? (_a_) : (_b_))
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#define sign(_a_) ((_a_) < 0.0 ? -1.0 : ((_a_) > 0.0 ? 1.0 : 0.0))
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#define mix(_x_,_y_,_a_) ((_x_) * (1.0 - (_a_)) + (_y_) * (_a_))
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static inline Color vec4mix(Color v1, Color v2, double a)
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{
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v1.r = mix(v1.r, v2.r, a);
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v1.g = mix(v1.g, v2.g, a);
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v1.b = mix(v1.b, v2.b, a);
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v1.a = mix(v1.a, v2.a, a);
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return v1;
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}
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static inline double clamp(double x, double minVal, double maxVal)
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{
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if (x < minVal)
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{
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x = minVal;
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}
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return (x > maxVal) ? maxVal : x;
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}
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static inline double smoothstep(double edge0, double edge1, double x)
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{
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double t = clamp((x - edge0) / (edge1 - edge0), 0.0, 1.0);
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return t * t * (3.0 - 2.0 * t);
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}
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static inline void _fixVec4Min(Color* vec, double minVal)
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{
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if (vec->r < minVal) { vec->r = minVal; }
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if (vec->g < minVal) { vec->g = minVal; }
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if (vec->b < minVal) { vec->b = minVal; }
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if (vec->a < minVal) { vec->a = minVal; }
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}
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static inline Color vec4max(Color vec, double minVal)
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{
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if (vec.r < minVal) { vec.r = minVal; }
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if (vec.g < minVal) { vec.g = minVal; }
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if (vec.b < minVal) { vec.b = minVal; }
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if (vec.a < minVal) { vec.a = minVal; }
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return vec;
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}
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static inline Vector3 vec3(double x, double y, double z)
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{
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Vector3 result;
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result.x = x;
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result.y = y;
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result.z = z;
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return result;
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}
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static inline Color vec4(double r, double g, double b, double a)
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{
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Color result;
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result.r = r;
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result.g = g;
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result.b = b;
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result.a = a;
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return result;
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}
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typedef struct
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{
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int xsize;
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int ysize;
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Color* data;
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} Texture2D;
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typedef struct
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{
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int xsize;
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int ysize;
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int zsize;
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Color* data;
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} Texture3D;
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/* Rayleigh phase function */
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static double _phaseFunctionR(double mu)
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@ -57,14 +137,16 @@ static double _phaseFunctionM(double mu)
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}
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/* approximated single Mie scattering (cf. approximate Cm in paragraph "Angular precision") */
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static Color _getMie(Color rayMie)
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Color getMie(Color rayMie)
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{
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double value = rayMie.a / max(rayMie.r, 1e-4) * (betaR.r / betaR); /* TODO divide by a vector ? */
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rayMie.r *= value;
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rayMie.g *= value;
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rayMie.b *= value;
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rayMie.a = 1.0;
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return rayMie;
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Color result;
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result.r = rayMie.r * rayMie.a / max(rayMie.r, 1e-4) * (betaR.r / betaR.r);
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result.g = rayMie.g * rayMie.a / max(rayMie.r, 1e-4) * (betaR.r / betaR.g);
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result.b = rayMie.b * rayMie.a / max(rayMie.r, 1e-4) * (betaR.r / betaR.b);
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result.a = 1.0;
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return result;
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}
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/* optical depth for ray (r,mu) of length d, using analytic formula
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@ -85,30 +167,145 @@ static double _opticalDepth(double H, double r, double mu, double d)
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return sqrt((6.2831 * H) * r) * exp((Rg - r) / H) * (x + yx - yy);
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}
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static Color _texture4D(sampler3D table, float r, float mu, float muS, float nu)
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static Texture3D _precomputeInscatterSampler()
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{
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float H = sqrt(Rt * Rt - Rg * Rg);
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float rho = sqrt(r * r - Rg * Rg);
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#ifdef INSCATTER_NON_LINEAR
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float rmu = r * mu;
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float delta = rmu * rmu - r * r + Rg * Rg;
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vec4 cst = rmu < 0.0 && delta > 0.0 ? vec4(1.0, 0.0, 0.0, 0.5 - 0.5 / float(RES_MU)) : vec4(-1.0, H * H, H, 0.5 + 0.5 / float(RES_MU));
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float uR = 0.5 / float(RES_R) + rho / H * (1.0 - 1.0 / float(RES_R));
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float uMu = cst.w + (rmu * cst.x + sqrt(delta + cst.y)) / (rho + cst.z) * (0.5 - 1.0 / float(RES_MU));
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// paper formula
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//float uMuS = 0.5 / float(RES_MU_S) + max((1.0 - exp(-3.0 * muS - 0.6)) / (1.0 - exp(-3.6)), 0.0) * (1.0 - 1.0 / float(RES_MU_S));
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// better formula
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float uMuS = 0.5 / float(RES_MU_S) + (atan(max(muS, -0.1975) * tan(1.26 * 1.1)) / 1.1 + (1.0 - 0.26)) * 0.5 * (1.0 - 1.0 / float(RES_MU_S));
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Texture3D result;
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result.xsize = 0;
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result.ysize = 0;
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result.zsize = 0;
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result.data = 0;
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return result;
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}
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Texture3D _inscatterSampler;
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/* nearest intersection of ray r,mu with ground or top atmosphere boundary
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* mu=cos(ray zenith angle at ray origin) */
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static double limit(double r, double mu)
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{
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double dout = -r * mu + sqrt(r * r * (mu * mu - 1.0) + RL * RL);
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double delta2 = r * r * (mu * mu - 1.0) + Rg * Rg;
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if (delta2 >= 0.0)
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{
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float din = -r * mu - sqrt(delta2);
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if (din >= 0.0) {
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dout = min(dout, din);
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}
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}
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return dout;
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}
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static double _opticalDepthTransmittance(double H, double r, double mu)
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{
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double result = 0.0;
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double dx = limit(r, mu) / (double)TRANSMITTANCE_INTEGRAL_SAMPLES;
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double xi = 0.0;
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double yi = exp(-(r - Rg) / H);
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int i;
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for (i = 1; i <= TRANSMITTANCE_INTEGRAL_SAMPLES; ++i) {
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double xj = (double)i * dx;
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double yj = exp(-(sqrt(r * r + xj * xj + 2.0 * xj * r * mu) - Rg) / H);
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result += (yi + yj) / 2.0 * dx;
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xi = xj;
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yi = yj;
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}
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return mu < -sqrt(1.0 - (Rg / r) * (Rg / r)) ? 1e9 : result;
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}
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static void _getTransmittanceRMu(double x, double y, double* r, double* muS)
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{
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#ifdef TRANSMITTANCE_NON_LINEAR
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*r = Rg + (y * y) * (Rt - Rg);
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*muS = -0.15 + tan(1.5 * x) / tan(1.5) * (1.0 + 0.15);
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#else
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float uR = 0.5 / float(RES_R) + rho / H * (1.0 - 1.0 / float(RES_R));
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float uMu = 0.5 / float(RES_MU) + (mu + 1.0) / 2.0 * (1.0 - 1.0 / float(RES_MU));
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float uMuS = 0.5 / float(RES_MU_S) + max(muS + 0.2, 0.0) / 1.2 * (1.0 - 1.0 / float(RES_MU_S));
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*r = Rg + y * (Rt - Rg);
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*muS = -0.15 + x * (1.0 + 0.15);
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#endif
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float lerp = (nu + 1.0) / 2.0 * (float(RES_NU) - 1.0);
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float uNu = floor(lerp);
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}
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static Color _debugSave2D(void* data, int x, int y)
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{
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Texture2D* tex = (Texture2D*)data;
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return tex->data[y * tex->xsize + x];
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}
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static Texture2D _precomputeTransmittanceSampler()
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{
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Texture2D result;
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int x, y;
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result.xsize = 256;
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result.ysize = 64;
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result.data = malloc(sizeof(Color) * result.xsize * result.ysize); /* TODO free */
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for (x = 0; x < result.xsize; x++)
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{
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for (y = 0; y < result.ysize; y++)
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{
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double r, muS;
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_getTransmittanceRMu((double)x / result.xsize, (double)y / result.ysize, &r, &muS);
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double depth1 = _opticalDepthTransmittance(HR, r, muS);
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double depth2 = _opticalDepthTransmittance(HM, r, muS);
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Color trans;
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trans.r = exp(-(betaR.r * depth1 + betaMEx.x * depth2));
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trans.g = exp(-(betaR.g * depth1 + betaMEx.y * depth2));
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trans.b = exp(-(betaR.b * depth1 + betaMEx.z * depth2));
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trans.a = 1.0;
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result.data[y * result.xsize + x] = trans; /* Eq (5) */
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}
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}
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/* DEBUG */
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systemSavePictureFile("debug.png", _debugSave2D, &result, result.xsize, result.ysize);
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return result;
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}
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Texture2D _transmittanceSampler;
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void brunetonInit()
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{
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_inscatterSampler = _precomputeInscatterSampler();
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_transmittanceSampler = _precomputeTransmittanceSampler();
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exit(1);
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}
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static Color _texture2D(Texture2D* tex, double x, double y)
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{
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/* TODO Sampling */
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return COLOR_BLACK;
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}
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static Color _texture3D(Texture3D* tex, Vector3 location)
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{
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/* TODO Sampling */
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return COLOR_BLACK;
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}
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static Color _texture4D(Texture3D* tex3d, double r, double mu, double muS, double nu)
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{
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double H = sqrt(Rt * Rt - Rg * Rg);
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double rho = sqrt(r * r - Rg * Rg);
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#ifdef INSCATTER_NON_LINEAR
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double rmu = r * mu;
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double delta = rmu * rmu - r * r + Rg * Rg;
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Color cst = (rmu < 0.0 && delta > 0.0) ? vec4(1.0, 0.0, 0.0, 0.5 - 0.5 / (double)(RES_MU)) : vec4(-1.0, H * H, H, 0.5 + 0.5 / (double)(RES_MU));
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double uR = 0.5 / (double)(RES_R) + rho / H * (1.0 - 1.0 / (double)(RES_R));
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double uMu = cst.a + (rmu * cst.r + sqrt(delta + cst.g)) / (rho + cst.b) * (0.5 - 1.0 / (double)(RES_MU));
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// paper formula
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//float uMuS = 0.5 / (double)(RES_MU_S) + max((1.0 - exp(-3.0 * muS - 0.6)) / (1.0 - exp(-3.6)), 0.0) * (1.0 - 1.0 / (double)(RES_MU_S));
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// better formula
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double uMuS = 0.5 / (double)(RES_MU_S) + (atan(max(muS, -0.1975) * tan(1.26 * 1.1)) / 1.1 + (1.0 - 0.26)) * 0.5 * (1.0 - 1.0 / (double)(RES_MU_S));
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#else
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float uR = 0.5 / (double)(RES_R) + rho / H * (1.0 - 1.0 / (double)(RES_R));
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float uMu = 0.5 / (double)(RES_MU) + (mu + 1.0) / 2.0 * (1.0 - 1.0 / (double)(RES_MU));
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float uMuS = 0.5 / (double)(RES_MU_S) + max(muS + 0.2, 0.0) / 1.2 * (1.0 - 1.0 / (double)(RES_MU_S));
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#endif
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double lerp = (nu + 1.0) / 2.0 * ((double)(RES_NU) - 1.0);
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double uNu = floor(lerp);
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lerp = lerp - uNu;
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return texture3D(table, vec3((uNu + uMuS) / float(RES_NU), uMu, uR)) * (1.0 - lerp) +
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texture3D(table, vec3((uNu + uMuS + 1.0) / float(RES_NU), uMu, uR)) * lerp;
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return vec4mix(_texture3D(tex3d, vec3((uNu + uMuS + 1.0) / (double)(RES_NU), uMu, uR)), _texture3D(tex3d, vec3((uNu + uMuS) / (double)(RES_NU), uMu, uR)), lerp);
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}
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/* transmittance(=transparency) of atmosphere for ray (r,mu) of length d
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@ -116,31 +313,53 @@ static Color _texture4D(sampler3D table, float r, float mu, float muS, float nu)
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uses analytic formula instead of transmittance texture */
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static Vector3 _analyticTransmittance(double r, double mu, double d)
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{
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return exp(-betaR * _opticalDepth(HR, r, mu, d) - betaMEx * _opticalDepth(HM, r, mu, d));
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Vector3 result;
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double opt = _opticalDepth(HR, r, mu, d);
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result.x = exp(-betaR.r * opt) - betaMEx.x * opt;
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result.y = exp(-betaR.g * opt) - betaMEx.y * opt;
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result.z = exp(-betaR.b * opt) - betaMEx.z * opt;
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return result;
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}
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static inline Color _applyInscatter(Color inscatter, Color attmod, Color samp)
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{
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inscatter.r = inscatter.r - attmod.r * samp.r;
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inscatter.g = inscatter.g - attmod.g * samp.g;
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inscatter.b = inscatter.b - attmod.b * samp.b;
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inscatter.a = inscatter.a - attmod.a * samp.a;
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return vec4max(inscatter, 0.0);
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}
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/* inscattered light along ray x+tv, when sun in direction s (=S[L]-T(x,x0)S[L]|x0) */
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static Color _inscatter(Vector3* x, double* t, Vector3 v, Vector3 s, double* _r, double* _mu, Color* attenuation)
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static Color _inscatter(Vector3* _x, double* _t, Vector3 v, Vector3 s, double* _r, double* _mu, Vector3* attenuation)
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{
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Color result;
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double r = v3Norm(x);
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double mu = v3Dot(x, v) / r;
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double r = v3Norm(*_x);
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double mu = v3Dot(*_x, v) / r;
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double d = -r * mu - sqrt(r * r * (mu * mu - 1.0) + Rt * Rt);
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if (d > 0.0)
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{ // if x in space and ray intersects atmosphere
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// move x to nearest intersection of ray with top atmosphere boundary
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x += d * v;
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t -= d;
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{
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/* if x in space and ray intersects atmosphere
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move x to nearest intersection of ray with top atmosphere boundary */
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_x->x += d * v.x;
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_x->y += d * v.y;
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_x->z += d * v.z;
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*_t -= d;
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mu = (r * mu + d) / Rt;
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r = Rt;
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}
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double t = *_t;
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Vector3 x = *_x;
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if (r <= Rt)
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{ // if ray intersects atmosphere
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{
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/* if ray intersects atmosphere */
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double nu = v3Dot(v, s);
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double muS = v3Dot(x, s) / r;
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double phaseR = _phaseFunctionR(nu);
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double phaseM = _phaseFunctionM(nu);
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vec4 inscatter = max(texture4D(inscatterSampler, r, mu, muS, nu), 0.0);
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Color inscatter = vec4max(_texture4D(&_inscatterSampler, r, mu, muS, nu), 0.0);
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if (t > 0.0)
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{
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Vector3 x0 = v3Add(x, v3Scale(v, t));
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@ -149,50 +368,58 @@ static Color _inscatter(Vector3* x, double* t, Vector3 v, Vector3 s, double* _r,
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double mu0 = rMu0 / r0;
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double muS0 = v3Dot(x0, s) / r0;
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#ifdef FIX
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||||
// avoids imprecision problems in transmittance computations based on textures
|
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/* avoids imprecision problems in transmittance computations based on textures */
|
||||
*attenuation = _analyticTransmittance(r, mu, t);
|
||||
#else
|
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*attenuation = _transmittance(r, mu, v, x0);
|
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#endif
|
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if (r0 > Rg + 0.01)
|
||||
{
|
||||
// computes S[L]-T(x,x0)S[L]|x0
|
||||
inscatter = max(inscatter - attenuation.rgbr * texture4D(inscatterSampler, r0, mu0, muS0, nu), 0.0);
|
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/* computes S[L]-T(x,x0)S[L]|x0 */
|
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Color attmod = {attenuation->x, attenuation->y, attenuation->z, attenuation->x};
|
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Color samp = _texture4D(&_inscatterSampler, r0, mu0, muS0, nu);
|
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inscatter = _applyInscatter(inscatter, attmod, samp);
|
||||
#ifdef FIX
|
||||
// avoids imprecision problems near horizon by interpolating between two points above and below horizon
|
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const float EPS = 0.004;
|
||||
float muHoriz = -sqrt(1.0 - (Rg / r) * (Rg / r));
|
||||
if (abs(mu - muHoriz) < EPS)
|
||||
/* avoids imprecision problems near horizon by interpolating between two points above and below horizon */
|
||||
const double EPS = 0.004;
|
||||
double muHoriz = -sqrt(1.0 - (Rg / r) * (Rg / r));
|
||||
if (fabs(mu - muHoriz) < EPS)
|
||||
{
|
||||
float a = ((mu - muHoriz) + EPS) / (2.0 * EPS);
|
||||
double a = ((mu - muHoriz) + EPS) / (2.0 * EPS);
|
||||
|
||||
mu = muHoriz - EPS;
|
||||
r0 = sqrt(r * r + t * t + 2.0 * r * t * mu);
|
||||
mu0 = (r * mu + t) / r0;
|
||||
vec4 inScatter0 = texture4D(inscatterSampler, r, mu, muS, nu);
|
||||
vec4 inScatter1 = texture4D(inscatterSampler, r0, mu0, muS0, nu);
|
||||
vec4 inScatterA = max(inScatter0 - attenuation.rgbr * inScatter1, 0.0);
|
||||
Color inScatter0 = _texture4D(&_inscatterSampler, r, mu, muS, nu);
|
||||
Color inScatter1 = _texture4D(&_inscatterSampler, r0, mu0, muS0, nu);
|
||||
Color inScatterA = _applyInscatter(inScatter0, attmod, inScatter1);
|
||||
|
||||
mu = muHoriz + EPS;
|
||||
r0 = sqrt(r * r + t * t + 2.0 * r * t * mu);
|
||||
mu0 = (r * mu + t) / r0;
|
||||
inScatter0 = texture4D(inscatterSampler, r, mu, muS, nu);
|
||||
inScatter1 = texture4D(inscatterSampler, r0, mu0, muS0, nu);
|
||||
vec4 inScatterB = max(inScatter0 - attenuation.rgbr * inScatter1, 0.0);
|
||||
inScatter0 = _texture4D(&_inscatterSampler, r, mu, muS, nu);
|
||||
inScatter1 = _texture4D(&_inscatterSampler, r0, mu0, muS0, nu);
|
||||
Color inScatterB = _applyInscatter(inScatter0, attmod, inScatter1);
|
||||
|
||||
inscatter = mix(inScatterA, inScatterB, a);
|
||||
inscatter = vec4mix(inScatterA, inScatterB, a);
|
||||
}
|
||||
#endif
|
||||
}
|
||||
}
|
||||
#ifdef FIX
|
||||
// avoids imprecision problems in Mie scattering when sun is below horizon
|
||||
inscatter.w *= smoothstep(0.00, 0.02, muS);
|
||||
/* avoids imprecision problems in Mie scattering when sun is below horizon */
|
||||
inscatter.a *= smoothstep(0.00, 0.02, muS);
|
||||
#endif
|
||||
result = max(inscatter.rgb * phaseR + getMie(inscatter) * phaseM, 0.0);
|
||||
Color mie = getMie(inscatter);
|
||||
result.r = inscatter.r * phaseR + mie.r * phaseM;
|
||||
result.g = inscatter.g * phaseR + mie.g * phaseM;
|
||||
result.b = inscatter.b * phaseR + mie.b * phaseM;
|
||||
result.a = inscatter.a * phaseR + mie.a * phaseM;
|
||||
_fixVec4Min(&result, 0.0);
|
||||
}
|
||||
else
|
||||
{ // x in space and ray looking in space
|
||||
{
|
||||
/* x in space and ray looking in space */
|
||||
result = COLOR_BLACK;
|
||||
}
|
||||
|
||||
|
|
@ -207,7 +434,6 @@ static Color _inscatter(Vector3* x, double* t, Vector3 v, Vector3 s, double* _r,
|
|||
|
||||
/*ground radiance at end of ray x+tv, when sun in direction s
|
||||
*attenuated bewteen ground and viewer (=R[L0]+R[L*]) */
|
||||
|
||||
/*static Color _groundColor(Vector3 x, double t, Vector3 v, Vector3 s, double r, double mu, Color attenuation)
|
||||
{
|
||||
Color result;
|
||||
|
|
@ -273,8 +499,8 @@ static inline void _getTransmittanceUV(double r, double mu, double* u, double* v
|
|||
static Color _transmittance(double r, double mu)
|
||||
{
|
||||
double u, v;
|
||||
_getTransmittanceUV(r, mu, u, v);
|
||||
return texture2D(transmittanceSampler, uv).rgb;
|
||||
_getTransmittanceUV(r, mu, &u, &v);
|
||||
return _texture2D(&_transmittanceSampler, u, v);
|
||||
}
|
||||
|
||||
/* transmittance(=transparency) of atmosphere for infinite ray (r,mu)
|
||||
|
|
@ -295,7 +521,11 @@ static Color _sunColor(Vector3 x, double t, Vector3 v, Vector3 s, double r, doub
|
|||
{
|
||||
Color transmittance = r <= Rt ? _transmittanceWithShadow(r, mu) : COLOR_WHITE; // T(x,xo)
|
||||
double isun = step(cos(M_PI / 180.0), v3Dot(v, s)) * ISun; // Lsun
|
||||
return transmittance * isun; // Eq (9)
|
||||
transmittance.r *= isun;
|
||||
transmittance.g *= isun;
|
||||
transmittance.b *= isun;
|
||||
transmittance.a *= isun;
|
||||
return transmittance; // Eq (9)
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -303,7 +533,11 @@ static Color _hdr(Color c1, Color c2, Color c3)
|
|||
{
|
||||
Color L = {c1.r + c2.r + c3.r, c1.g + c2.g + c3.g, c1.b + c2.b + c3.b, 1.0};
|
||||
|
||||
L = L * exposure;
|
||||
L.r *= exposure;
|
||||
L.g *= exposure;
|
||||
L.b *= exposure;
|
||||
L.a *= exposure;
|
||||
|
||||
L.r = L.r < 1.413 ? pow(L.r * 0.38317, 1.0 / 2.2) : 1.0 - exp(-L.r);
|
||||
L.g = L.g < 1.413 ? pow(L.g * 0.38317, 1.0 / 2.2) : 1.0 - exp(-L.g);
|
||||
L.b = L.b < 1.413 ? pow(L.b * 0.38317, 1.0 / 2.2) : 1.0 - exp(-L.b);
|
||||
|
|
@ -342,7 +576,7 @@ Color brunetonGetSkyColor(AtmosphereDefinition* definition, Vector3 eye, Vector3
|
|||
}
|
||||
|
||||
Vector3 attenuation;
|
||||
Color inscatterColor = _inscatter(x, t, v, s, &r, &mu, &attenuation); //S[L]-T(x,xs)S[l]|xs
|
||||
Color inscatterColor = _inscatter(&x, &t, v, s, &r, &mu, &attenuation); //S[L]-T(x,xs)S[l]|xs
|
||||
/*Color groundColor = _groundColor(x, t, v, s, r, mu, attenuation); //R[L0]+R[L*]*/
|
||||
Color groundColor = COLOR_BLACK;
|
||||
Color sunColor = _sunColor(x, t, v, s, r, mu); //L0
|
||||
|
|
|
|||
|
|
@ -28,6 +28,8 @@ static AtmosphereDefinition* _createDefinition()
|
|||
{
|
||||
AtmosphereDefinition* result;
|
||||
|
||||
// brunetonInit(); /* DEBUG */
|
||||
|
||||
result = malloc(sizeof(AtmosphereDefinition));
|
||||
result->model = ATMOSPHERE_MODEL_PREETHAM;
|
||||
result->daytime = 0.0;
|
||||
|
|
|
|||
|
|
@ -3,6 +3,7 @@
|
|||
|
||||
#define SPHERE_SIZE 1000.0
|
||||
|
||||
void brunetonInit();
|
||||
Color brunetonGetSkyColor(AtmosphereDefinition* definition, Vector3 eye, Vector3 direction, Vector3 sun_position);
|
||||
|
||||
Color preethamGetSkyColor(AtmosphereDefinition* definition, Vector3 eye, Vector3 direction, Vector3 sun_position);
|
||||
|
|
|
|||
Loading…
Reference in a new issue