Procedural Electric Current Shader

arlez80 April 12, 2022April 12, 2022

A procedural electric current shader.

Shader code

/*
	動的電撃シェーダー by あるる（きのもと 結衣）
	Procedural Electric Current Shader by Yui Kinomoto @arlez80

	MIT License
*/
shader_type spatial;
render_mode unshaded, blend_add;

uniform vec4 light_color : hint_color = vec4( 0.32, 0.5, 0.82, 0.5 );
uniform vec4 arc_color : hint_color = vec4( 0.46, 0.68, 1.0, 1.0 );

uniform vec2 seed = vec2( 0.0, 0.0 );
uniform float speed = 5.1;
uniform float random_scale = 4.6;
uniform float electro_scale = 11.459;

vec2 random( vec2 pos )
{ 
	return fract(
		sin(
			vec2(
				dot(pos, vec2(12.9898,78.233))
			,	dot(pos, vec2(-148.998,-65.233))
			)
		) * 43758.5453
	);
}

float value_noise( vec2 pos )
{
	vec2 p = floor( pos );
	vec2 f = fract( pos );

	float v00 = random( p + vec2( 0.0, 0.0 ) ).x;
	float v10 = random( p + vec2( 1.0, 0.0 ) ).x;
	float v01 = random( p + vec2( 0.0, 1.0 ) ).x;
	float v11 = random( p + vec2( 1.0, 1.0 ) ).x;

	vec2 u = f * f * ( 3.0 - 2.0 * f );

	return mix( mix( v00, v10, u.x ), mix( v01, v11, u.x ), u.y );
}

float noise_tex( vec2 p )
{
	return (
		value_noise( p * 0.984864 ) * 0.5
	+	value_noise( p * 2.543 ) * 0.25
	+	value_noise( p * 9.543543 ) * 0.125
	+	value_noise( p * 21.65436 ) * 0.0625
	+	value_noise( p * 42.0 ) * 0.03125
	+	value_noise( p * 87.135148 ) * 0.015625
	+	value_noise( p * 340.66534654 ) * 0.0078125
	);
}

void fragment( )
{
	vec2 uv = seed + vec2( UV.x + cos( TIME * 1321.21 + UV.y * 348.513 ) * 0.004, UV.y + sin( TIME * 421.21 + UV.x * 314.513 ) * 0.0016 );
	float f = abs( cos( TIME * speed + noise_tex( uv * random_scale ) * electro_scale ) );

	ALBEDO = mix( light_color, arc_color, 1.0 - clamp( ( f - 0.08 ) * 20.0, 0.0, 1.0 ) ).rgb;
	ALPHA = 1.0 - clamp( ( f - 0.3 ) * 3.0, 0.0, 1.0 );
}