Add initial Sponza benchmark (#47)

* add Sponza.dae and related assets

files copied from: https://github.com/Calinou/godot-sponza/tree/4.0-dev

* [wip] add sponza benchmark

* add script to tweak sponza materials

* add omni lights + enable shadows

* Remove unused resources from Sponza

* Convert Sponza to glTF + lossless WebP

This greatly decreases file size and speeds up loading.

---------

Co-authored-by: Hugo Locurcio <hugo.locurcio@hugo.pro>

benchmarks/rendering/sponza.gd

@@ -0,0 +1,47 @@
+extends Benchmark
+
+func _init():
+	test_render_cpu = true
+	test_render_gpu = true
+
+
+class TestScene extends Node3D:
+	
+	var sponza_scene = preload("res://benchmarks/rendering/sponza.tscn")
+	var sponza
+	
+	var using_directional_light: bool
+	var using_omni_lights: bool
+	
+	func _init():
+		sponza = sponza_scene.instantiate()
+		add_child(sponza)
+	
+	func with_directional_light():
+		using_directional_light = true
+		return self
+		
+	func with_omni_lights():
+		using_omni_lights = true
+		return self
+		
+	func _ready():
+		$"Sponza/DirectionalLight3D".visible = using_directional_light
+		$"Sponza/OmniLights".visible = using_omni_lights
+
+	func _process(delta):
+		pass
+
+	func _exit_tree():
+		RenderingServer.free_rid(sponza)
+
+
+func benchmark_sponza_ambient():
+	return TestScene.new()
+	
+func benchmark_sponza_directional():
+	return TestScene.new().with_directional_light()
+	
+func benchmark_sponza_omni():
+	return TestScene.new().with_omni_lights()
+

benchmarks/rendering/sponza.tscn

@@ -0,0 +1,57 @@
+[gd_scene load_steps=2 format=3 uid="uid://lhj56divlnw3"]
+
+[ext_resource type="PackedScene" uid="uid://b0c2qturgt8i6" path="res://thirdparty/sponza/sponza.glb" id="1_1w3b0"]
+
+[node name="Sponza" type="Node3D"]
+
+[node name="sponza" parent="." instance=ExtResource("1_1w3b0")]
+
+[node name="Camera3D" type="Camera3D" parent="."]
+transform = Transform3D(-4.37114e-08, 3.48787e-16, 1, 3.48787e-16, 1, -3.48787e-16, -1, 3.48787e-16, -4.37114e-08, 7.25, 0.9, -0.225)
+current = true
+
+[node name="DirectionalLight3D" type="DirectionalLight3D" parent="."]
+transform = Transform3D(0.5, -0.852869, 0.150384, 6.05662e-17, 0.173648, 0.984808, -0.866025, -0.492404, 0.0868241, 0, 0, 0)
+shadow_enabled = true
+
+[node name="OmniLights" type="Node3D" parent="."]
+
+[node name="OmniLight3D" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 3.05361, 0.966716, 0.907753)
+light_energy = 0.5
+shadow_enabled = true
+
+[node name="OmniLight3D2" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 3.05361, 0.966716, -1.35595)
+light_energy = 0.5
+shadow_enabled = true
+
+[node name="OmniLight3D3" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -3.85783, 0.966716, 0.907753)
+light_energy = 0.5
+shadow_enabled = true
+
+[node name="OmniLight3D4" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -3.85783, 0.966716, -1.35595)
+light_energy = 0.5
+shadow_enabled = true
+
+[node name="OmniLight3D5" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 6.99073, 1.39109, 2.534)
+light_color = Color(1, 0.584314, 0, 1)
+shadow_enabled = true
+
+[node name="OmniLight3D6" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 6.99073, 1.39109, -2.80553)
+light_color = Color(0, 1, 0, 1)
+shadow_enabled = true
+
+[node name="OmniLight3D7" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -7.5058, 1.39109, 2.534)
+light_color = Color(0.701961, 0, 1, 1)
+shadow_enabled = true
+
+[node name="OmniLight3D8" type="OmniLight3D" parent="OmniLights"]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -7.5058, 1.39109, -2.80553)
+light_color = Color(0, 0, 1, 1)
+shadow_enabled = true