shader_type spatial;
render_mode blend_add, depth_draw_never, cull_back;

uniform vec4 albedo : source_color;
uniform sampler2D texture_albedo : source_color, filter_linear_mipmap, repeat_enable;

uniform float fresnelScale = 1.0;
uniform float fresnelPower = 1.0;
uniform float normalGrowth = 0;
uniform float growthMax = 2;

uniform float driver:hint_range(0.0, 1.0) = 0;
varying float driverCurve;


void vertex()
{
  float d = length( CAMERA_POSITION_WORLD - NODE_POSITION_WORLD );
  driverCurve = sin( driver * PI );
  VERTEX += NORMAL * normalGrowth * d * ( driver * growthMax );
}

void fragment()
{
  float fresnel = pow( 1.0 - abs( NORMAL.z ), fresnelPower ) * fresnelScale;
  fresnel = clamp( fresnel, 0.0, 1.0 );
	vec4 albedo_tex = texture( texture_albedo, UV );
	ALBEDO = albedo.rgb * albedo_tex.rgb;
	ALPHA *= albedo.a * albedo_tex.a * fresnel * driverCurve;
}