X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=builtin_data%2F_sky.glsl;h=1dbda5793f2d838018b1f8558ede2da7f03437da;hb=2729c824049bd59c16370a60a90824a416755a62;hp=81f9d16398693ba16018b9f17ebe9bfbd04b780b;hpb=a5f76ec38d682108e8c655a25b32b88e19bd8783;p=libs%2Fgl.git

diff --git a/builtin_data/_sky.glsl b/builtin_data/_sky.glsl
index 81f9d163..1dbda579 100644
--- a/builtin_data/_sky.glsl
+++ b/builtin_data/_sky.glsl
@@ -88,13 +88,8 @@ float ray_sphere_intersect(vec3 ray_start, vec3 ray_dir, vec3 sphere_center, flo
 	if(d_sq>r_sq)
 		return -1.0;
 
-	float offset = sqrt(r_sq-d_sq);
-	if(offset<t)
-		return t-offset;
-	else if(offset>-t)
-		return t+offset;
-	else
-		return -1.0;
+	float offset = sqrt(r_sq-d_sq)*sign(sphere_radius);
+	return t-offset;
 }
 
 #pragma MSP stage(fragment)
@@ -110,7 +105,7 @@ OpticalPathInfo raymarch_path(float start_height, vec3 look_dir)
 	vec3 path_extinction = vec3(0.0);
 
 	float ground_t = ray_sphere_intersect(pos, look_dir, planet_center, planet_radius);
-	float space_t = ray_sphere_intersect(pos, look_dir, planet_center, planet_radius+atmosphere_thickness);
+	float space_t = ray_sphere_intersect(pos, look_dir, planet_center, -(planet_radius+atmosphere_thickness));
 	float ray_length = (ground_t>0.0 ? ground_t : space_t);
 	float step_size = ray_length/n_steps;
 
@@ -123,7 +118,7 @@ OpticalPathInfo raymarch_path(float start_height, vec3 look_dir)
 
 		AtmosphericEvents ev = calculate_events(height);
 		vec3 transmittance = exp(-path_extinction);
-		float in_ground_t = ray_sphere_intersect(pos+light_dir, light_dir, planet_center, planet_radius);
+		float in_ground_t = ray_sphere_intersect(pos, light_dir, planet_center, planet_radius);
 		if(in_ground_t<0.0)
 		{
 			vec3 in_transmittance = texture(transmittance_lookup, vec2(sqrt(height/atmosphere_thickness), light_z)).rgb;