#version 120
//#extension GL_EXT_gpu_shader4 : disable
#include "/lib/settings.glsl"
//Computes volumetric clouds at variable resolution (default 1/4 res)



flat varying vec3 sunColor;
flat varying vec3 moonColor;

flat varying vec3 averageSkyCol_Clouds;



flat varying float tempOffsets;
uniform float far;
uniform float near;
uniform sampler2D depthtex0;
// uniform sampler2D colortex4;
uniform sampler2D noisetex;

flat varying vec3 WsunVec;
uniform vec3 sunVec;
uniform vec2 texelSize;
uniform float frameTimeCounter;
uniform float rainStrength;
uniform int frameCounter;
uniform int framemod8;
uniform mat4 gbufferProjectionInverse;
uniform mat4 gbufferModelViewInverse;
uniform vec3 cameraPosition;

uniform mat4 gbufferModelView;
// flat varying vec2 TAA_Offset;


vec3 toScreenSpace(vec3 p) {
	vec4 iProjDiag = vec4(gbufferProjectionInverse[0].x, gbufferProjectionInverse[1].y, gbufferProjectionInverse[2].zw);
    vec3 p3 = p * 2. - 1.;
    vec4 fragposition = iProjDiag * p3.xyzz + gbufferProjectionInverse[3];
    return fragposition.xyz / fragposition.w;
}
float R2_dither(){
	vec2 alpha = vec2(0.75487765, 0.56984026);
	return fract(alpha.x * gl_FragCoord.x + alpha.y * gl_FragCoord.y + 1.0/1.6180339887 * frameCounter);
}
float R2_dither2(){
	vec2 alpha = vec2(0.75487765, 0.56984026);
	return fract(alpha.x * (1.0-gl_FragCoord.x) + alpha.y * (1.0-gl_FragCoord.y) + 1.0/1.6180339887 * frameCounter);
}
float interleaved_gradientNoise(){
	vec2 alpha = vec2(0.75487765, 0.56984026);
	vec2 coord = vec2(alpha.x * gl_FragCoord.x,alpha.y * gl_FragCoord.y)+ 1.0/1.6180339887 * frameCounter;
	float noise = fract(52.9829189*fract(0.06711056*coord.x + 0.00583715*coord.y));
	return noise;
}
#include "/lib/sky_gradient.glsl"
#include "/lib/volumetricClouds.glsl"
#include "/lib/res_params.glsl"
const vec2[8] offsets = vec2[8](vec2(1./8.,-3./8.),
							vec2(-1.,3.)/8.,
							vec2(5.0,1.)/8.,
							vec2(-3,-5.)/8.,
							vec2(-5.,5.)/8.,
							vec2(-7.,-1.)/8.,
							vec2(3,7.)/8.,
							vec2(7.,-7.)/8.);
float blueNoise(){
  return fract(texelFetch2D(noisetex, ivec2(1.0-gl_FragCoord.xy)%512, 0).a + 1.0/1.6180339887 * frameCounter);
}
float blueNoise2(){
  return fract(texelFetch2D(noisetex, ivec2(gl_FragCoord.xy)%512, 0).a + 1.0/1.6180339887 * frameCounter);
}

vec3 normVec (vec3 vec){
	return vec*inversesqrt(dot(vec,vec));
}

//////////////////////////////VOID MAIN//////////////////////////////
//////////////////////////////VOID MAIN//////////////////////////////
//////////////////////////////VOID MAIN//////////////////////////////
//////////////////////////////VOID MAIN//////////////////////////////
//////////////////////////////VOID MAIN//////////////////////////////


void main() {
/* DRAWBUFFERS:0 */

#ifdef VOLUMETRIC_CLOUDS
	// vec2 halfResTC = vec2(floor(gl_FragCoord.xy)/CLOUDS_QUALITY/RENDER_SCALE+0.5+(vec2(tempOffsets)*(texelSize/4))*CLOUDS_QUALITY*RENDER_SCALE*0.5);

	vec2 halfResTC = vec2(floor(gl_FragCoord.xy)/CLOUDS_QUALITY/RENDER_SCALE+0.5+offsets[framemod8]*CLOUDS_QUALITY*RENDER_SCALE*0.5);

	float z = texture2D(depthtex0,halfResTC*texelSize).x;

	vec3 fragpos = toScreenSpace(vec3(halfResTC*texelSize,1));


	vec4 currentClouds = renderClouds(fragpos,vec2(R2_dither(),blueNoise2()), sunColor/80., moonColor/150., (averageSkyCol_Clouds*2.0)* 8./150./3.);
	
	gl_FragData[0] = currentClouds;
	

#else
	gl_FragData[0] = vec4(0.0,0.0,0.0,1.0);
#endif
}