Hey. thanks for letting me know. Here's a quick little fix:
- Click on the "shader" button to see the shader code.
- Add this line: "float d_circle = distance(uv, vec2(0.5));" on line 74. Just before the line "uv = spherify(uv);".
- On line 96, replace "a *= step(distance(vec2(0.5), uv), 0.5);" with the line "a *= step(d_circle, 0.5);"
I just tested it and that works for me. It's actually a mistake I made in the original shader code, but it seems like godot 3 handles it different than 4.
Hope that helps!