made visual updates

pixelate.gdshader

@@ -0,0 +1,15 @@
+shader_type canvas_item;
+
+uniform sampler2D SCREEN_TEXTURE: hint_screen_texture, filter_linear_mipmap;
+
+uniform int pixel_size : hint_range(1, 64) = 4; // Pixel size
+uniform vec2 screen_size = vec2(1920.0, 1080.0); // Screen size (set manually)
+
+void fragment() {
+    //Pixel coordinates in screen space
+    vec2 pixel_coords = floor(FRAGCOORD.xy / float(pixel_size)) * float(pixel_size);
+    // Convert pixel coordinates to UVs for screen texture
+    vec2 uv = pixel_coords / screen_size;
+    // Get color from texture screen
+    COLOR = texture(SCREEN_TEXTURE, uv);
+}