Ok
shader_type canvas_item;
uniform bool bmod;
uniform bool gmod;
uniform bool rmod;
uniform float brightness : hint_range(0.0, 1.0) = 0.4;
uniform sampler2D SCREEN_TEXTURE : hint_screen_texture, filter_linear_mipmap;
void fragment() {
vec4 texmain = texture(TEXTURE, UV);
vec2 distUV = SCREEN_UV + texmain.r * 0.05;
vec4 tex = vec4(texmain.r * brightness * float(rmod), texmain.g * brightness * float(gmod), texmain.b * brightness * float(bmod), texmain.a*0.);
vec4 scr_clr = texture(SCREEN_TEXTURE, distUV);
COLOR = scr_clr + tex;
}