Re-add optional OIDN denoise as an external executable.

3 files changed, 14 insertions, 1 deletions

diff --git a/doc/classes/EditorSettings.xml b/doc/classes/EditorSettings.xml
index 00b591b385..6edd8af7cc 100644
--- a/doc/classes/EditorSettings.xml
+++ b/doc/classes/EditorSettings.xml
@@ -500,6 +500,10 @@
 			If [code]true[/code], when saving a file, the editor will rename the old file to a different name, save a new file, then only remove the old file once the new file has been saved. This makes loss of data less likely to happen if the editor or operating system exits unexpectedly while saving (e.g. due to a crash or power outage).
 			[b]Note:[/b] On Windows, this feature can interact negatively with certain antivirus programs. In this case, you may have to set this to [code]false[/code] to prevent file locking issues.
 		</member>
+		<member name="filesystem/tools/oidn/oidn_denoise_path" type="String" setter="" getter="">
+			The path to the directory containing the Open Image Denoise (OIDN) executable, used optionally for denoising lightmaps. It can be downloaded from [url=https://www.openimagedenoise.org/downloads.html]openimagedenoise.org[/url].
+			To enable this feature for your specific project, use [member ProjectSettings.rendering/lightmapping/denoising/denoiser].
+		</member>
 		<member name="interface/editor/accept_dialog_cancel_ok_buttons" type="int" setter="" getter="">
 			How to position the Cancel and OK buttons in the editor's [AcceptDialog]s. Different platforms have different standard behaviors for this, which can be overridden using this setting. This is useful if you use Godot both on Windows and macOS/Linux and your Godot muscle memory is stronger than your OS specific one.
 			- [b]Auto[/b] follows the platform convention: Cancel first on macOS and Linux, OK first on Windows.
diff --git a/doc/classes/LightmapGI.xml b/doc/classes/LightmapGI.xml
index 5a050eb256..3dad9b7e56 100644
--- a/doc/classes/LightmapGI.xml
+++ b/doc/classes/LightmapGI.xml
@@ -25,7 +25,7 @@
 			The [CameraAttributes] resource that specifies exposure levels to bake at. Auto-exposure and non exposure properties will be ignored. Exposure settings should be used to reduce the dynamic range present when baking. If exposure is too high, the [LightmapGI] will have banding artifacts or may have over-exposure artifacts.
 		</member>
 		<member name="denoiser_strength" type="float" setter="set_denoiser_strength" getter="get_denoiser_strength" default="0.1">
-			The strength of denoising step applied to the generated lightmaps. Only effective if [member use_denoiser] is [code]true[/code].
+			The strength of denoising step applied to the generated lightmaps. Only effective if [member use_denoiser] is [code]true[/code] and [member ProjectSettings.rendering/lightmapping/denoising/denoiser] is set to JNLM.
 		</member>
 		<member name="directional" type="bool" setter="set_directional" getter="is_directional" default="false">
 			If [code]true[/code], bakes lightmaps to contain directional information as spherical harmonics. This results in more realistic lighting appearance, especially with normal mapped materials and for lights that have their direct light baked ([member Light3D.light_bake_mode] set to [constant Light3D.BAKE_STATIC]). The directional information is also used to provide rough reflections for static and dynamic objects. This has a small run-time performance cost as the shader has to perform more work to interpret the direction information from the lightmap. Directional lightmaps also take longer to bake and result in larger file sizes.
diff --git a/doc/classes/ProjectSettings.xml b/doc/classes/ProjectSettings.xml
index 581097565f..a79d31f7c6 100644
--- a/doc/classes/ProjectSettings.xml
+++ b/doc/classes/ProjectSettings.xml
@@ -2446,6 +2446,15 @@
 		<member name="rendering/lightmapping/bake_quality/ultra_quality_ray_count" type="int" setter="" getter="" default="1024">
 			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">
+			Denoiser tool used for denoising lightmaps.
+			Using [url=https://www.openimagedenoise.org/]OpenImageDenoise[/url] (OIDN) requires configuring a path to an OIDN executable in the editor settings at [member EditorSettings.filesystem/tools/oidn/oidn_denoise_path]. OIDN can be downloaded from [url=https://www.openimagedenoise.org/downloads.html]OpenImageDenoise's downloads page[/url].
+			OIDN will use GPU acceleration when available. Unlike JNLM which uses compute shaders for acceleration, OIDN uses vendor-specific acceleration methods. For GPU acceleration to be available, the following libraries must be installed on the system depending on your GPU:
+			- NVIDIA GPUs: CUDA libraries
+			- AMD GPUs: HIP libraries
+			- Intel GPUs: SYCL libraries
+			If no GPU acceleration is configured on the system, multi-threaded CPU-based denoising will be performed instead. This CPU-based denoising is significantly slower than the JNLM denoiser in most cases.
+		</member>
 		<member name="rendering/lightmapping/primitive_meshes/texel_size" type="float" setter="" getter="" default="0.2">
 			The texel_size that is used to calculate the [member Mesh.lightmap_size_hint] on [PrimitiveMesh] resources if [member PrimitiveMesh.add_uv2] is enabled.
 		</member>