InSpace.tres

[gd_resource type="ShaderMaterial" load_steps=2 format=2]

[sub_resource type="Shader" id=1]
code = "shader_type spatial;
render_mode unshaded, shadows_disabled, specular_disabled, ambient_light_disabled, cull_disabled;

// Star Nest by Pablo Roman Andrioli

// This content is under the MIT License.

uniform int iterations=17;
uniform float formuparam =0.53;

uniform int volsteps= 20;
uniform float stepsize= 0.1;

//uniform float zoom  = 0.800;
//uniform float tile =  0.850;
//uniform float speed = 0.010 ;

uniform float brightness= 0.0015;
uniform float darkmatter= 0.300;
uniform float distfading =0.730;
uniform float saturation =0.850;


void fragment()
{
	// Replace animation based on time and mouse movement with a direction
	// calculated from the camera's world view
	vec4 worldview=CAMERA_MATRIX*vec4(VIEW, .0);
	vec3 dir=worldview.xyz;
	vec3 from=vec3(1.,.5,-1.5);

/*
	//get coords and direction
    vec2 iResolution=1.0/VIEWPORT_SIZE;
	vec2 uv=FRAGCOORD.xy/iResolution.xy-.5;
	uv.y*=iResolution.y/iResolution.x;
	vec3 dir=vec3(uv*zoom,1.);
	float time=TIME*speed+.25;

	//mouse rotation
	vec2 iMouse=vec2(0.0, 0.0);
	float a1=.5+iMouse.x/iResolution.x*2.;
	float a2=.8+iMouse.y/iResolution.y*2.;
	mat2 rot1=mat2(vec2(cos(a1),sin(a1)),vec2(-sin(a1),cos(a1)));
	mat2 rot2=mat2(vec2(cos(a2),sin(a2)),vec2(-sin(a2),cos(a2)));
	dir.xz*=rot1;
	dir.xy*=rot2;
	vec3 from=vec3(1.,.5,0.5);
	from+=vec3(time*2.,time,-2.);
	from.xz*=rot1;
	from.xy*=rot2;
	*/

	//volumetric rendering
	float s=0.1,fade=1.;
	vec3 v=vec3(0.);
	for (int r=0; r<volsteps; r++) {
		vec3 p=from+s*dir*.5;
		//p = abs(vec3(tile)-mod(p,vec3(tile*2.))); // tiling fold
		float pa,a=pa=0.;
		for (int i=0; i<iterations; i++) { 
			p=abs(p)/dot(p,p)-formuparam; // the magic formula
			a+=abs(length(p)-pa); // absolute sum of average change
			pa=length(p);
		}
		float dm=max(0.,darkmatter-a*a*.001); //dark matter
		a*=a*a; // add contrast
		if (r>6) fade*=1.-dm; // dark matter, don't render near
		//v+=vec3(dm,dm*.5,0.);
		v+=fade;
		v+=vec3(s,s*s,s*s*s*s)*a*brightness*fade; // coloring based on distance
		fade*=distfading; // distance fading
		s+=stepsize;
	}
	v=mix(vec3(length(v)),v,saturation); //color adjust
	ALBEDO = v*.001;
}"

[resource]
shader = SubResource( 1 )
shader_param/iterations = 18
shader_param/formuparam = 0.53
shader_param/volsteps = 20
shader_param/stepsize = 0.1
shader_param/brightness = 0.0015
shader_param/darkmatter = 0.3
shader_param/distfading = 0.73
shader_param/saturation = 0.85