Cleanup

Shaders/std/sky.glsl

@@ -66,25 +66,15 @@ vec3 nishita_lookupLUT(const float height, const float sunTheta) {
 	return textureLod(nishitaLUT, coords, 0.0).rgb;
 }
 
-/* Approximates the density of ozone for a given sample height. Values taken from Cycles code. */
+/* See raySphereIntersection() in armory/Sources/renderpath/Nishita.hx */
-float nishita_density_ozone(const float height) {
-	return (height < 10000.0 || height >= 40000.0) ? 0.0 : (height < 25000.0 ? (height - 10000.0) / 15000.0 : -((height - 40000.0) / 15000.0));
-}
-
-/* ray-sphere intersection that assumes
- * the sphere is centered at the origin.
- * No intersection when result.x > result.y */
 vec2 nishita_rsi(const vec3 r0, const vec3 rd, const float sr) {
 	float a = dot(rd, rd);
 	float b = 2.0 * dot(rd, r0);
 	float c = dot(r0, r0) - (sr * sr);
 	float d = (b*b) - 4.0*a*c;
 
-	if (d < 0.0) return vec2(1e5,-1e5);
+	// If d < 0.0 the ray does not intersect the sphere
-	return vec2(
+	return (d < 0.0) ? vec2(1e5,-1e5) : vec2((-b - sqrt(d))/(2.0*a), (-b + sqrt(d))/(2.0*a));
-		(-b - sqrt(d))/(2.0*a),
-		(-b + sqrt(d))/(2.0*a)
-	);
 }
 
 /*
@@ -94,43 +84,41 @@ vec2 nishita_rsi(const vec3 r0, const vec3 rd, const float sr) {
  * rPlanet: planet radius
  */
 vec3 nishita_atmosphere(const vec3 r, const vec3 r0, const vec3 pSun, const float rPlanet) {
-	// Calculate the step size of the primary ray.
+	// Calculate the step size of the primary ray
 	vec2 p = nishita_rsi(r0, r, nishita_atmo_radius);
-	if (p.x > p.y) return vec3(0,0,0);
+	if (p.x > p.y) return vec3(0.0);
 	p.y = min(p.y, nishita_rsi(r0, r, rPlanet).x);
 	float iStepSize = (p.y - p.x) / float(nishita_iSteps);
 
-	// Initialize the primary ray time.
+	// Primary ray time
 	float iTime = 0.0;
 
-	// Initialize accumulators for Rayleigh and Mie scattering.
+	// Accumulators for Rayleigh and Mie scattering.
 	vec3 totalRlh = vec3(0,0,0);
 	vec3 totalMie = vec3(0,0,0);
 
-	// Initialize optical depth accumulators for the primary ray.
+	// Optical depth accumulators for the primary ray
 	float iOdRlh = 0.0;
 	float iOdMie = 0.0;
 
-	// Calculate the Rayleigh and Mie phases.
+	// Calculate the Rayleigh and Mie phases
 	float mu = dot(r, pSun);
 	float mumu = mu * mu;
 	float pRlh = 3.0 / (16.0 * PI) * (1.0 + mumu);
 	float pMie = 3.0 / (8.0 * PI) * ((1.0 - nishita_mie_dir_sq) * (mumu + 1.0)) / (pow(1.0 + nishita_mie_dir_sq - 2.0 * mu * nishita_mie_dir, 1.5) * (2.0 + nishita_mie_dir_sq));
 
-	// Sample the primary ray.
+	// Sample the primary ray
 	for (int i = 0; i < nishita_iSteps; i++) {
 
-		// Calculate the primary ray sample position.
+		// Calculate the primary ray sample position and height
 		vec3 iPos = r0 + r * (iTime + iStepSize * 0.5);
-
-		// Calculate the height of the sample.
 		float iHeight = length(iPos) - rPlanet;
 
 		// Calculate the optical depth of the Rayleigh and Mie scattering for this step
 		float odStepRlh = exp(-iHeight / nishita_rayleigh_scale) * nishitaDensity.x * iStepSize;
 		float odStepMie = exp(-iHeight / nishita_mie_scale) * nishitaDensity.y * iStepSize;
 
-		// Accumulate optical depth.
+		// Accumulate optical depth
 		iOdRlh += odStepRlh;
 		iOdMie += odStepMie;
 
@@ -142,22 +130,20 @@ vec3 nishita_atmosphere(const vec3 r, const vec3 r0, const vec3 pSun, const floa
 		// Apply dithering to reduce visible banding
 		jODepth += mix(-1000, 1000, random(r.xy));
 
-		// Calculate attenuation.
+		// Calculate attenuation
 		vec3 attn = exp(-(
 			nishita_mie_coeff * (iOdMie + jODepth.y)
 			+ (nishita_rayleigh_coeff) * (iOdRlh + jODepth.x)
 			+ nishita_ozone_coeff * jODepth.z
 		));
 
-		// Accumulate scattering.
+		// Accumulate scattering
 		totalRlh += odStepRlh * attn;
 		totalMie += odStepMie * attn;
 
-		// Increment the primary ray time.
 		iTime += iStepSize;
 	}
 
-	// Calculate and return the final color.
 	return nishita_sun_intensity * (pRlh * nishita_rayleigh_coeff * totalRlh + pMie * nishita_mie_coeff * totalMie);
 }
 
@@ -166,7 +152,7 @@ vec3 sun_disk(const vec3 n, const vec3 light_dir, const float disk_size, const f
 	float dist = distance(n, light_dir) / disk_size;
 
 	// Darken the edges of the sun
-	// [Hill: 28, 60] (code from [Nec96])
+	// [Hill: 28, 60] (according to [Nec96])
 	float invDist = 1.0 - dist;
 	float mu = sqrt(invDist * invDist);
 	vec3 limb_darkening = 1.0 - (1.0 - pow(vec3(mu), sun_limb_darkening_col));

Sources/armory/object/Uniforms.hx

@@ -177,9 +177,9 @@ class Uniforms {
 		var v: Vec4 = null;
 		switch (link) {
 			case "_nishitaDensity": {
-				v = iron.object.Uniforms.helpVec;
 				var w = Scene.active.world;
 				if (w != null) {
+					v = iron.object.Uniforms.helpVec;
 					// We only need Rayleigh and Mie density in the sky shader -> Vec2
 					v.x = w.raw.nishita_density[0];
 					v.y = w.raw.nishita_density[1];

blender/arm/material/cycles_nodes/nodes_texture.py

@@ -296,7 +296,7 @@ def parse_tex_sky(node: bpy.types.ShaderNodeTexSky, out_socket: bpy.types.NodeSo
 
     if node.sky_type == 'PREETHAM' or node.sky_type == 'HOSEK_WILKIE':
         if node.sky_type == 'PREETHAM':
-            log.warn('Preetham sky model is not supported, using Hosek Wilkie sky model instead')
+            log.info('Info: Preetham sky model is not supported, using Hosek Wilkie sky model instead')
 
         return parse_sky_hosekwilkie(node, state)