Removed sun inflating near horizon

This is only a popular belief and a psychologically
perceived illusion (not optical).

src/render/opengl/shaders/atmosphere.frag

@@ -90,8 +90,6 @@ vec4 _transmittanceWithShadow(float r, float mu)
 vec4 _sunTransmittance(vec3 v, vec3 s, float r, float mu, float radius)
 {
     vec4 transmittance = r <= Rt ? _transmittanceWithShadow(r, mu) : vec4(1.0); /* T(x,xo) */
-    float d = _limit(r, mu);
-    radius *= (1.0 + 15.0 * d / Rt); /* Inflating due to lens effect near horizon */
     float isun = step(cos(radius), dot(v, s)) * ISun; /* Lsun */
     transmittance.r *= isun;
     transmittance.g *= isun;

src/render/software/AtmosphereModelBruneton.cpp

@@ -860,8 +860,6 @@ static Color _getInscatterColor(Vector3 *_x, double *_t, Vector3 v, Vector3 s, d
 /* direct sun light for ray x+tv, when sun in direction s (=L0) */
 static Color _sunColor(Vector3 v, Vector3 s, double r, double mu, double radius) {
     Color transmittance = r <= Rt ? _transmittanceWithShadow(r, mu) : COLOR_WHITE; /* T(x,xo) */
-    double d = _limit(r, mu);
-    radius *= (1.0 + 15.0 * d / Rt);                         /* Inflating due to lens effect near horizon */
     double isun = step(cos(radius), v.dotProduct(s)) * ISun; /* Lsun */
     transmittance.r *= isun;
     transmittance.g *= isun;