first commit

shaderpacks/Reimagined - High/shaders/lib/atmospherics/fog/endCenterFog.glsl

@@ -0,0 +1,18 @@
+#if !defined END_CENTER_FOG
+#define END_CENTER_FOG
+float doEndCenterFog(vec3 ro, vec3 rayDir, float wsdist, float falloff) { // Thanks to FoZy STYLE
+    vec3 d = ro - vec3(0.5, 60.5, 0.5); // Light source vector
+    d.y *= 0.7;
+    rayDir.y *= 0.7;
+
+    float a = falloff * dot(rayDir, rayDir);
+    float b  = 2.0 * falloff * dot(rayDir, d);
+    float c = 1.0 + falloff * dot(d, d);
+
+    float sqrtDiscr = max(0.001, sqrt(4.0 * a * c - b * b));
+    float upper = (2.0 * a * wsdist + b) / sqrtDiscr;
+    float lower = b / sqrtDiscr;
+
+    return 2.0 * (atan(upper) - atan(lower)) / sqrtDiscr;
+}
+#endif