// https://www.shadertoy.com/view/XljBW3

#define vec2 float2
#define vec3 float3
#define vec4 float4
#define ivec2 int2
#define ivec3 int3
#define ivec4 int4
#define mat2 float2x2
#define mat3 float3x3
#define mat4 float4x4
#define fract frac
#define mix lerp
#define iTime Time.x
#define iResolution ViewSize

uniform float2 mouse<
	string name = "Virtual Mouse Coordinates";
	string field_type = "slider";
	float2 minimum = {0, 0};
	float2 maximum = {100., 100.};
	float2 scale = {.01, .01};
	float2 step = {.01, .01};
> = {0., 0.};

uniform float4x4 ViewProj<
	bool automatic = true;
>;

uniform bool direction<
	string name = "Invert Direction";
> = true;

uniform float4 Time<
	bool automatic = true;
>;

uniform float4 ViewSize<
	bool automatic = true;
>;

int2 iMouse() {
	return int2(mouse.x * ViewSize.x, mouse.y * ViewSize.y);
}

/* ps start

*/
#define time iTime
uniform float ratio;

#define PI2 6.28318530718
#define PI 3.1416

float vorocloud(float2 p){
	float f = 0.0;
	float flow = 1.0;
	if(direction){
		flow *= -1;
	}
    float2 pp = cos(float2(p.x * 14.0, (16.0 * p.y + cos(floor(p.x * 30.0)) + flow * time * PI2)) );
    p = cos(p * 12.1 + pp * 10.0 + 0.5 * cos(pp.x * 10.0));
    
    float2 pts[4];    
    
    pts[0] = float2(0.5, 0.6);
    pts[1] = float2(-0.4, 0.4);
    pts[2] = float2(0.2, -0.7);
    pts[3] = float2(-0.3, -0.4);
    
    float d = 5.0;
    
    for(int i = 0; i < 4; i++){
      	pts[i].x += 0.03 * cos(float(i)) + p.x;
      	pts[i].y += 0.03 * sin(float(i)) + p.y;
    	d = min(d, distance(pts[i], pp));
    }
    
    f = 2.0 * pow(1.0 - 0.3 * d, 13.0);
    
    f = min(f, 1.0);
    
	return f;
}

vec4 scene(float2 UV){
    float x = UV.x;
    float y = UV.y;
    
    float2 p = float2(x, y) - 0.5;
    
    vec4 col = vec4(0.0,0.0,0.0,0.0);
	col.g += 0.02;
    
    float v = vorocloud(p);
    v = 0.2 * floor(v * 5.0);
    
    col.r += 0.1 * v;
    col.g += 0.6 * v;
    col.b += 0.5 * pow(v, 5.0);
    
    
    v = vorocloud(p * 2.0);
    v = 0.2 * floor(v * 5.0);
    
    col.r += 0.1 * v;
    col.g += 0.2 * v;
    col.b += 0.01 * pow(v, 5.0);
    
    col.a = 1.0;
    
    return col;
}

void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
	vec2 uv = fragCoord.xy / iResolution.xy;
	fragColor = scene(uv);
}

/*ps end*/

struct VertFragData {
	float4 pos : POSITION;
	float2 uv  : TEXCOORD0;
};

VertFragData VSDefault(VertFragData vtx) {
	vtx.pos = mul(float4(vtx.pos.xyz, 1.0), ViewProj);
	return vtx;
}

float4 PSDefault(VertFragData vtx) : TARGET {
	float4 col = float4(1., 1., 1., 1.);
	mainImage(col, vtx.uv * ViewSize.xy);
	return col;
}

technique Draw 
{
	pass
	{
		vertex_shader = VSDefault(vtx);
		pixel_shader  = PSDefault(vtx); 
	}
}