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++ void MAIN()
++ {
++ vec2 size = vec2(textureSize(SCREEN_TEXTURE, 0));
++ vec2 uv = FRAGCOORD.xy / size;
++
++ vec3 view = normalize(VIEW_VECTOR);
++ vec3 projection = view - view * normalize(NORMAL);
++ vec3 refraction = projection * projection;
++ uv += refraction.xy * 0.5;
++
++ vec3 col = texture(SCREEN_TEXTURE, uv).rgb;
++ col = col * 0.8 + vec3(0.2);
++
++ BASE_COLOR = vec4(col, 1.0);
++ }