godot parallax

tree.gd

extends TextureRect


var shader_material
var screen_size

func _ready():
	screen_size = OS.get_screen_size()
	shader_material = self.material
	set_process_input(true)

func _input(event):
	if event is InputEventMouseMotion:
		var norm_mouse = self.get_local_mouse_position()/screen_size
#		norm_mouse.y = 1.0-norm_mouse.y
		norm_mouse = (norm_mouse/2.0)
		print(norm_mouse)

		shader_material.set_shader_param("mouse_pos", norm_mouse)
	

treeshader.gdshader

shader_type canvas_item;

uniform vec2 mouse_pos;
uniform sampler2D dog;
uniform sampler2D depth_map;

void fragment(){
  COLOR = texture(dog, UV+mouse_pos*(texture(depth_map, UV).r)); //read from texture
}