Add Nearest Mipmap Anisotropic filter option to decals and projectors

This is consistent with the BaseMaterial3D filtering options.
It can be used for high-quality pixel art textures that remain sharp
when viewed at oblique angles, but prevents them from becoming grainy
thanks to mipmaps.

2 files changed, 25 insertions, 6 deletions

diff --git a/doc/classes/ProjectSettings.xml b/doc/classes/ProjectSettings.xml
index b1e3d2f628..ae0ec64c27 100644
--- a/doc/classes/ProjectSettings.xml
+++ b/doc/classes/ProjectSettings.xml
@@ -1962,9 +1962,11 @@
 			Lower-end override for [member rendering/shadows/positional_shadow/soft_shadow_filter_quality] on mobile devices, due to performance concerns or driver support.
 		</member>
 		<member name="rendering/textures/decals/filter" type="int" setter="" getter="" default="3">
+			The filtering quality to use for [Decal] nodes. When using one of the anisotropic filtering modes, the anisotropic filtering level is controlled by [member rendering/textures/default_filters/anisotropic_filtering_level].
 		</member>
 		<member name="rendering/textures/default_filters/anisotropic_filtering_level" type="int" setter="" getter="" default="2">
 			Sets the maximum number of samples to take when using anisotropic filtering on textures (as a power of two). A higher sample count will result in sharper textures at oblique angles, but is more expensive to compute. A value of [code]0[/code] forcibly disables anisotropic filtering, even on materials where it is enabled.
+			The anisotropic filtering level also affects decals and light projectors if they are configured to use anisotropic filtering. See [member rendering/textures/decals/filter] and [member rendering/textures/light_projectors/filter].
 			[b]Note:[/b] This property is only read when the project starts. There is currently no way to change this setting at run-time.
 		</member>
 		<member name="rendering/textures/default_filters/texture_mipmap_bias" type="float" setter="" getter="" default="0.0">
@@ -1977,6 +1979,7 @@
 			[b]Note:[/b] This property is only read when the project starts. There is currently no way to change this setting at run-time.
 		</member>
 		<member name="rendering/textures/light_projectors/filter" type="int" setter="" getter="" default="3">
+			The filtering quality to use for [OmniLight3D] and [SpotLight3D] projectors. When using one of the anisotropic filtering modes, the anisotropic filtering level is controlled by [member rendering/textures/default_filters/anisotropic_filtering_level].
 		</member>
 		<member name="rendering/textures/lossless_compression/force_png" type="bool" setter="" getter="" default="false">
 			If [code]true[/code], the texture importer will import lossless textures using the PNG format. Otherwise, it will default to using WebP.
diff --git a/doc/classes/RenderingServer.xml b/doc/classes/RenderingServer.xml
index 9616ab3515..9a398b1f33 100644
--- a/doc/classes/RenderingServer.xml
+++ b/doc/classes/RenderingServer.xml
@@ -3747,14 +3747,22 @@
 			Use [Transform3D] to store MultiMesh transform.
 		</constant>
 		<constant name="LIGHT_PROJECTOR_FILTER_NEAREST" value="0" enum="LightProjectorFilter">
+			Nearest-neighbor filter for light projectors (use for pixel art light projectors). No mipmaps are used for rendering, which means light projectors at a distance will look sharp but grainy. This has roughly the same performance cost as using mipmaps.
 		</constant>
-		<constant name="LIGHT_PROJECTOR_FILTER_NEAREST_MIPMAPS" value="1" enum="LightProjectorFilter">
+		<constant name="LIGHT_PROJECTOR_FILTER_LINEAR" value="1" enum="LightProjectorFilter">
+			Linear filter for light projectors (use for non-pixel art light projectors). No mipmaps are used for rendering, which means light projectors at a distance will look smooth but blurry. This has roughly the same performance cost as using mipmaps.
 		</constant>
-		<constant name="LIGHT_PROJECTOR_FILTER_LINEAR" value="2" enum="LightProjectorFilter">
+		<constant name="LIGHT_PROJECTOR_FILTER_NEAREST_MIPMAPS" value="2" enum="LightProjectorFilter">
+			Nearest-neighbor filter for light projectors (use for pixel art light projectors). Isotropic mipmaps are used for rendering, which means light projectors at a distance will look smooth but blurry. This has roughly the same performance cost as not using mipmaps.
 		</constant>
 		<constant name="LIGHT_PROJECTOR_FILTER_LINEAR_MIPMAPS" value="3" enum="LightProjectorFilter">
+			Linear filter for light projectors (use for non-pixel art light projectors). Isotropic mipmaps are used for rendering, which means light projectors at a distance will look smooth but blurry. This has roughly the same performance cost as not using mipmaps.
 		</constant>
-		<constant name="LIGHT_PROJECTOR_FILTER_LINEAR_MIPMAPS_ANISOTROPIC" value="4" enum="LightProjectorFilter">
+		<constant name="LIGHT_PROJECTOR_FILTER_NEAREST_MIPMAPS_ANISOTROPIC" value="4" enum="LightProjectorFilter">
+			Nearest-neighbor filter for light projectors (use for pixel art light projectors). Anisotropic mipmaps are used for rendering, which means light projectors at a distance will look smooth and sharp when viewed from oblique angles. This looks better compared to isotropic mipmaps, but is slower. The level of anisotropic filtering is defined by [member ProjectSettings.rendering/textures/default_filters/anisotropic_filtering_level].
+		</constant>
+		<constant name="LIGHT_PROJECTOR_FILTER_LINEAR_MIPMAPS_ANISOTROPIC" value="5" enum="LightProjectorFilter">
+			Linear filter for light projectors (use for non-pixel art light projectors). Anisotropic mipmaps are used for rendering, which means light projectors at a distance will look smooth and sharp when viewed from oblique angles. This looks better compared to isotropic mipmaps, but is slower. The level of anisotropic filtering is defined by [member ProjectSettings.rendering/textures/default_filters/anisotropic_filtering_level].
 		</constant>
 		<constant name="LIGHT_DIRECTIONAL" value="0" enum="LightType">
 			Is a directional (sun) light.
@@ -3896,14 +3904,22 @@
 		<constant name="DECAL_TEXTURE_MAX" value="4" enum="DecalTexture">
 		</constant>
 		<constant name="DECAL_FILTER_NEAREST" value="0" enum="DecalFilter">
+			Nearest-neighbor filter for decals (use for pixel art decals). No mipmaps are used for rendering, which means decals at a distance will look sharp but grainy. This has roughly the same performance cost as using mipmaps.
 		</constant>
-		<constant name="DECAL_FILTER_NEAREST_MIPMAPS" value="1" enum="DecalFilter">
+		<constant name="DECAL_FILTER_LINEAR" value="1" enum="DecalFilter">
+			Linear filter for decals (use for non-pixel art decals). No mipmaps are used for rendering, which means decals at a distance will look smooth but blurry. This has roughly the same performance cost as using mipmaps.
 		</constant>
-		<constant name="DECAL_FILTER_LINEAR" value="2" enum="DecalFilter">
+		<constant name="DECAL_FILTER_NEAREST_MIPMAPS" value="2" enum="DecalFilter">
+			Nearest-neighbor filter for decals (use for pixel art decals). Isotropic mipmaps are used for rendering, which means decals at a distance will look smooth but blurry. This has roughly the same performance cost as not using mipmaps.
 		</constant>
 		<constant name="DECAL_FILTER_LINEAR_MIPMAPS" value="3" enum="DecalFilter">
+			Linear filter for decals (use for non-pixel art decals). Isotropic mipmaps are used for rendering, which means decals at a distance will look smooth but blurry. This has roughly the same performance cost as not using mipmaps.
+		</constant>
+		<constant name="DECAL_FILTER_NEAREST_MIPMAPS_ANISOTROPIC" value="4" enum="DecalFilter">
+			Nearest-neighbor filter for decals (use for pixel art decals). Anisotropic mipmaps are used for rendering, which means decals at a distance will look smooth and sharp when viewed from oblique angles. This looks better compared to isotropic mipmaps, but is slower. The level of anisotropic filtering is defined by [member ProjectSettings.rendering/textures/default_filters/anisotropic_filtering_level].
 		</constant>
-		<constant name="DECAL_FILTER_LINEAR_MIPMAPS_ANISOTROPIC" value="4" enum="DecalFilter">
+		<constant name="DECAL_FILTER_LINEAR_MIPMAPS_ANISOTROPIC" value="5" enum="DecalFilter">
+			Linear filter for decals (use for non-pixel art decals). Anisotropic mipmaps are used for rendering, which means decals at a distance will look smooth and sharp when viewed from oblique angles. This looks better compared to isotropic mipmaps, but is slower. The level of anisotropic filtering is defined by [member ProjectSettings.rendering/textures/default_filters/anisotropic_filtering_level].
 		</constant>
 		<constant name="VOXEL_GI_QUALITY_LOW" value="0" enum="VoxelGIQuality">
 		</constant>