uniform sampler2D uTexGarbage;

in vec4 aColour;
in vec2 aUv;
in vec3 aNorm;
in vec3 aCo;
in vec3 aWorldCo;

// Spooky!
const vec3 uCamera = vec3(0.0);

#include "light_clearskies_stddef.glsl"
#include "common_world.glsl"
#include "motion_vectors_fs.glsl"

void main()
{
   compute_motion_vectors();

   vec3 rd = normalize(aNorm);

   float fmove = g_time * 5.0;
   vec2 cloudplane = (rd.xz / (rd.y*sign(rd.y))) * 0.025;
   vec4 clouds1 = texture( uTexGarbage, cloudplane + vec2(0.1,0.4)*fmove*2.0 );
   vec4 clouds2 = texture( uTexGarbage, cloudplane*2.0 + vec2(0.3,0.1)*fmove );

   float cloud_d = max(clouds1.b*clouds2.r -0.2 - clouds2.g*0.4,0.0);
   float cloud_e = pow(cloud_d,1.5)*pow(abs(rd.y),0.3)*2.0;

   oColour = vec4( clearskies_sky( -rd ) ,1.0);

   vec3 cloud_colour = mix( mix(g_nightsky_colour.rgb,vec3(1.0),g_day_phase), 
                                g_sunset_colour.rgb, g_sunset_phase );

   oColour.rgb = mix( oColour.rgb, cloud_colour, cloud_e );
}