Pixelize / Mosaic (overlay)
Yet another pixelize shader, this one was made specifically for full-screen overlays utilizing SCREEN_TEXTURE.
Shader code
shader_type canvas_item;
uniform float amount: hint_range(1.0, 640.0, 1.0);
void fragment()
{
vec2 amt = 1.0 / amount / SCREEN_PIXEL_SIZE;
vec2 uv = round(SCREEN_UV * amt) / amt;
vec4 c = textureLod(SCREEN_TEXTURE, uv, 0);
COLOR = c;
}