Merge pull request #82068 from DarioSamo/lightmapper-indirect-bounces

Rewrite the GPU Lightmapper's indirect logic to match Godot 3.5's CPU Lightmapper.

doc/classes/LightmapGI.xml

@@ -18,6 +18,10 @@
 		<member name="bias" type="float" setter="set_bias" getter="get_bias" default="0.0005">
 			The bias to use when computing shadows. Increasing [member bias] can fix shadow acne on the resulting baked lightmap, but can introduce peter-panning (shadows not connecting to their casters). Real-time [Light3D] shadows are not affected by this [member bias] property.
 		</member>
+		<member name="bounce_indirect_energy" type="float" setter="set_bounce_indirect_energy" getter="get_bounce_indirect_energy" default="1.0">
+			The energy multiplier for each bounce. Higher values will make indirect lighting brighter. A value of [code]1.0[/code] represents physically accurate behavior, but higher values can be used to make indirect lighting propagate more visibly when using a low number of bounces. This can be used to speed up bake times by lowering the number of [member bounces] then increasing [member bounce_indirect_energy].
+			[b]Note:[/b] [member bounce_indirect_energy] only has an effect if [member bounces] is set to a value greater than or equal to [code]1[/code].
+		</member>
 		<member name="bounces" type="int" setter="set_bounces" getter="get_bounces" default="3">
 			Number of light bounces that are taken into account during baking. Higher values result in brighter, more realistic lighting, at the cost of longer bake times. If set to [code]0[/code], only environment lighting, direct light and emissive lighting is baked.
 		</member>
@@ -64,6 +68,10 @@
 		<member name="use_denoiser" type="bool" setter="set_use_denoiser" getter="is_using_denoiser" default="true">
 			If [code]true[/code], uses a GPU-based denoising algorithm on the generated lightmap. This eliminates most noise within the generated lightmap at the cost of longer bake times. File sizes are generally not impacted significantly by the use of a denoiser, although lossless compression may do a better job at compressing a denoised image.
 		</member>
+		<member name="use_texture_for_bounces" type="bool" setter="set_use_texture_for_bounces" getter="is_using_texture_for_bounces" default="true">
+			If [code]true[/code], a texture with the lighting information will be generated to speed up the generation of indirect lighting at the cost of some accuracy. The geometry might exhibit extra light leak artifacts when using low resolution lightmaps or UVs that stretch the lightmap significantly across surfaces. Leave [member use_texture_for_bounces] at its default value of [code]true[/code] if unsure.
+			[b]Note:[/b] [member use_texture_for_bounces] only has an effect if [member bounces] is set to a value greater than or equal to [code]1[/code].
+		</member>
 	</members>
 	<constants>
 		<constant name="BAKE_QUALITY_LOW" value="0" enum="BakeQuality">

doc/classes/ProjectSettings.xml

@@ -2425,25 +2425,25 @@
 		<member name="rendering/lightmapping/bake_quality/high_quality_probe_ray_count" type="int" setter="" getter="" default="512">
 			The number of rays to use for baking dynamic object lighting in [LightmapProbe]s when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_HIGH].
 		</member>
-		<member name="rendering/lightmapping/bake_quality/high_quality_ray_count" type="int" setter="" getter="" default="256">
+		<member name="rendering/lightmapping/bake_quality/high_quality_ray_count" type="int" setter="" getter="" default="512">
 			The number of rays to use for baking lightmaps with [LightmapGI] when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_HIGH].
 		</member>
 		<member name="rendering/lightmapping/bake_quality/low_quality_probe_ray_count" type="int" setter="" getter="" default="64">
 			The number of rays to use for baking dynamic object lighting in [LightmapProbe]s when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_LOW].
 		</member>
-		<member name="rendering/lightmapping/bake_quality/low_quality_ray_count" type="int" setter="" getter="" default="16">
+		<member name="rendering/lightmapping/bake_quality/low_quality_ray_count" type="int" setter="" getter="" default="32">
 			The number of rays to use for baking lightmaps with [LightmapGI] when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_LOW].
 		</member>
 		<member name="rendering/lightmapping/bake_quality/medium_quality_probe_ray_count" type="int" setter="" getter="" default="256">
 			The number of rays to use for baking dynamic object lighting in [LightmapProbe]s when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_MEDIUM].
 		</member>
-		<member name="rendering/lightmapping/bake_quality/medium_quality_ray_count" type="int" setter="" getter="" default="64">
+		<member name="rendering/lightmapping/bake_quality/medium_quality_ray_count" type="int" setter="" getter="" default="128">
 			The number of rays to use for baking lightmaps with [LightmapGI] when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_MEDIUM].
 		</member>
 		<member name="rendering/lightmapping/bake_quality/ultra_quality_probe_ray_count" type="int" setter="" getter="" default="2048">
 			The number of rays to use for baking dynamic object lighting in [LightmapProbe]s when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_ULTRA].
 		</member>
-		<member name="rendering/lightmapping/bake_quality/ultra_quality_ray_count" type="int" setter="" getter="" default="1024">
+		<member name="rendering/lightmapping/bake_quality/ultra_quality_ray_count" type="int" setter="" getter="" default="2048">
 			The number of rays to use for baking lightmaps with [LightmapGI] when [member LightmapGI.quality] is [constant LightmapGI.BAKE_QUALITY_ULTRA].
 		</member>
 		<member name="rendering/lightmapping/denoising/denoiser" type="int" setter="" getter="" default="0">