remove synchronization from World.Render

benchmark                  old ns/op     new ns/op     delta
BenchmarkRender480p        12156087      11414856      -6.10%
BenchmarkRender480pSS      14266629      13547401      -5.04%
BenchmarkRender720p        25755589      24254185      -5.83%
BenchmarkRender720pSS      31345839      29341530      -6.39%
BenchmarkRender1080p       52205978      47423446      -9.16%
BenchmarkRender1080pSS     53293193      52278659      -1.90%
BenchmarkRender4K          188417063     186992100     -0.76%
BenchmarkRender4KSS        159282338     148954478     -6.48%

benchmark                  old allocs     new allocs     delta
BenchmarkRender480p        42             42             +0.00%
BenchmarkRender480pSS      130            130            +0.00%
BenchmarkRender720p        42             42             +0.00%
BenchmarkRender720pSS      130            130            +0.00%
BenchmarkRender1080p       42             42             +0.00%
BenchmarkRender1080pSS     130            130            +0.00%
BenchmarkRender4K          42             42             +0.00%
BenchmarkRender4KSS        130            130            +0.00%

benchmark                  old bytes     new bytes     delta
BenchmarkRender480p        726           726           +0.00%
BenchmarkRender480pSS      2424          2422          -0.08%
BenchmarkRender720p        726           726           +0.00%
BenchmarkRender720pSS      2422          2422          +0.00%
BenchmarkRender1080p       714           714           +0.00%
BenchmarkRender1080pSS     2422          2418          -0.17%
BenchmarkRender4K          680           680           +0.00%
BenchmarkRender4KSS        2395          2395          +0.00%