Add Sponza Global Illumination benchmarks

[OverloadedOrama]

Adds the following benchmarks from #36:

• 🟩GPU🟩 [GI]: Sponza lightmapped: Sponza lit with directional light, lightmapped only (lights all baked static).
• 🟩GPU🟩 [GI]: Sponza with RefProbe: Sponza with directional light, with GI reflection probe.
• 🟩GPU🟩 [GI]: Sponza with VoxelGI: Sponza with directional light, with GI from VoxelGI
• 🟩GPU🟩 [GI]: Sponza with SDFGI: Sponza with directional light, with GI from SDFGI
• 🟩GPU🟩 [GI]: Sponza with SSGI: Sponza with directional light, with GI from SSGI (SSIL)

I also formatted sponza.gd and improved static typing as recommended in CONTRIBUTING.md.

Results on my PC

{ "benchmarks": [ { "category": "Rendering > Sponza", "name": "Gi Lightmap", "results": { "render_cpu": 0.3715, "render_gpu": 3.329, "time": 0.198 } }, { "category": "Rendering > Sponza", "name": "Gi Refprobe", "results": { "render_cpu": 0.4218, "render_gpu": 3.955, "time": 0.151 } }, { "category": "Rendering > Sponza", "name": "Gi Sdfgi", "results": { "render_cpu": 0.4167, "render_gpu": 6.264, "time": 0.222 } }, { "category": "Rendering > Sponza", "name": "Gi Ssil", "results": { "render_cpu": 0.4794, "render_gpu": 5.997, "time": 0.137 } }, { "category": "Rendering > Sponza", "name": "Gi Voxelgi", "results": { "render_cpu": 0.4084, "render_gpu": 6.519, "time": 0.195 } } ], "engine": { "version": "v4.3.beta1.official", "version_hash": "a4f2ea91a1bd18f70a43ff4c1377db49b56bc3f0" }, "system": { "cpu_architecture": "x86_64", "cpu_count": 12, "cpu_name": "AMD Ryzen 5 1600 Six-Core Processor", "os": "Linux" } }

[Calinou]

Edit: Disregard what was said below, removing my local .godot/ folder and reopening the editor did the trick. All benchmarks look correct now 🙂

---

Tested locally, it mostly works as expected.

There is one issue though: I don't see lightmaps at all when running the LightmapGI benchmark. It seems the LightmapGIData resource is invalid, as I can get it to work if I do the following:

• Remove the existing LightmapGIData resource.
• Reimport sponza.glb from the Import dock.
• Create a LightmapGI node and bake it again.

Note that hidden lights will still have their light baked, but it's not an issue for this particular benchmark.