Implemented AMD's FSR as a computer shader for upscaling 3D scenes

3 files changed, 74 insertions, 11 deletions

diff --git a/doc/classes/ProjectSettings.xml b/doc/classes/ProjectSettings.xml
index 69ee51ca99..7fdac7ccd4 100644
--- a/doc/classes/ProjectSettings.xml
+++ b/doc/classes/ProjectSettings.xml
@@ -1506,12 +1506,8 @@
 		</member>
 		<member name="rendering/2d/snap/snap_2d_vertices_to_pixel" type="bool" setter="" getter="" default="false">
 		</member>
-		<member name="rendering/3d/viewport/scale" type="float" setter="" getter="" default="1.0">
-			Scales the 3D render buffer based on the viewport size and displays the result with linear filtering. Values lower than [code]1.0[/code] can be used to speed up 3D rendering at the cost of quality (undersampling). Values greater than [code]1.0[/code] can be used to improve 3D rendering quality at a high performance cost (supersampling). See also [member rendering/anti_aliasing/quality/msaa] for multi-sample antialiasing, which is significantly cheaper but only smoothens the edges of polygons.
-			[b]Note:[/b] This property is only read when the project starts. To change the 3D rendering resolution scale at runtime, set [member Viewport.scale_3d] instead.
-		</member>
 		<member name="rendering/anti_aliasing/quality/msaa" type="int" setter="" getter="" default="0">
-			Sets the number of MSAA samples to use (as a power of two). MSAA is used to reduce aliasing around the edges of polygons. A higher MSAA value results in smoother edges but can be significantly slower on some hardware. See also [member rendering/3d/viewport/scale] for supersampling, which provides higher quality but is much more expensive.
+			Sets the number of MSAA samples to use (as a power of two). MSAA is used to reduce aliasing around the edges of polygons. A higher MSAA value results in smoother edges but can be significantly slower on some hardware. See also bilinear scaling 3d [member rendering/scaling_3d/mode] for supersampling, which provides higher quality but is much more expensive.
 		</member>
 		<member name="rendering/anti_aliasing/quality/screen_space_aa" type="int" setter="" getter="" default="0">
 			Sets the screen-space antialiasing mode for the default screen [Viewport]. Screen-space antialiasing works by selectively blurring edges in a post-process shader. It differs from MSAA which takes multiple coverage samples while rendering objects. Screen-space AA methods are typically faster than MSAA and will smooth out specular aliasing, but tend to make scenes appear blurry.
@@ -1718,6 +1714,18 @@
 		<member name="rendering/reflections/sky_reflections/texture_array_reflections.mobile" type="bool" setter="" getter="" default="false">
 			Lower-end override for [member rendering/reflections/sky_reflections/texture_array_reflections] on mobile devices, due to performance concerns or driver support.
 		</member>
+		<member name="rendering/scaling_3d/fsr_mipmap_bias" type="float" setter="" getter="" default="0.0">
+			Affects the final texture sharpness by reading from a lower or higher mipmap. Negative values make textures sharper, while positive values make textures blurrier. When using FSR, this value is used to adjust the mipmap bias calculated internally which is based on the selected quality. The formula for this is [code]-log2(1.0 / scale) + mipmap_bias[/code]
+		</member>
+		<member name="rendering/scaling_3d/fsr_sharpness" type="float" setter="" getter="" default="0.2">
+			Determines how sharp the upscaled image will be when using the FSR upscaling mode. Sharpness halves with every whole number. Values go from 0.0 (sharpest) to 2.0. Values above 2.0 won't make a visible difference.
+		</member>
+		<member name="rendering/scaling_3d/mode" type="int" setter="" getter="" default="0">
+			Sets the scaling 3D mode. Bilinear scaling renders at different resolution to either undersample or supersample the viewport. FidelityFX Super Resolution 1.0, abbreviated to FSR, is an upscaling technology that produces high quality images at fast framerates by using a spatially aware upscaling algorithm. FSR is slightly more expensive than bilinear, but it produces significantly higher image quality. FSR should be used where possible.
+		</member>
+		<member name="rendering/scaling_3d/scale" type="float" setter="" getter="" default="1.0">
+			Scales the 3D render buffer based on the viewport size uses an image filter specified in [member rendering/scaling_3d/mode] to scale the output image to the full viewport size. Values lower than [code]1.0[/code] can be used to speed up 3D rendering at the cost of quality (undersampling). Values greater than [code]1.0[/code] are only valid for bilinear mode and can be used to improve 3D rendering quality at a high performance cost (supersampling). See also [member rendering/anti_aliasing/quality/msaa] for multi-sample antialiasing, which is significantly cheaper but only smoothens the edges of polygons.
+		</member>
 		<member name="rendering/shader_compiler/shader_cache/compress" type="bool" setter="" getter="" default="true">
 		</member>
 		<member name="rendering/shader_compiler/shader_cache/enabled" type="bool" setter="" getter="" default="true">
diff --git a/doc/classes/RenderingServer.xml b/doc/classes/RenderingServer.xml
index 7f4d5cf1cd..0700650a91 100644
--- a/doc/classes/RenderingServer.xml
+++ b/doc/classes/RenderingServer.xml
@@ -3100,6 +3100,22 @@
 				If [code]true[/code], rendering of a viewport's environment is disabled.
 			</description>
 		</method>
+		<method name="viewport_set_fsr_mipmap_bias">
+			<return type="void" />
+			<argument index="0" name="viewport" type="RID" />
+			<argument index="1" name="mipmap_bias" type="float" />
+			<description>
+				Affects the final texture sharpness by reading from a lower or higher mipmap. Negative values make textures sharper, while positive values make textures blurrier. When using FSR, this value is used to adjust the mipmap bias calculated internally which is based on the selected quality. The formula for this is [code]-log2(1.0 / scale) + mipmap_bias[/code]
+			</description>
+		</method>
+		<method name="viewport_set_fsr_sharpness">
+			<return type="void" />
+			<argument index="0" name="viewport" type="RID" />
+			<argument index="1" name="sharpness" type="float" />
+			<description>
+				Determines how sharp the upscaled image will be when using the FSR upscaling mode. Sharpness halves with every whole number. Values go from 0.0 (sharpest) to 2.0. Values above 2.0 won't make a visible difference.
+			</description>
+		</method>
 		<method name="viewport_set_global_canvas_transform">
 			<return type="void" />
 			<argument index="0" name="viewport" type="RID" />
@@ -3151,12 +3167,21 @@
 				If [code]true[/code], render the contents of the viewport directly to screen. This allows a low-level optimization where you can skip drawing a viewport to the root viewport. While this optimization can result in a significant increase in speed (especially on older devices), it comes at a cost of usability. When this is enabled, you cannot read from the viewport or from the [code]SCREEN_TEXTURE[/code]. You also lose the benefit of certain window settings, such as the various stretch modes. Another consequence to be aware of is that in 2D the rendering happens in window coordinates, so if you have a viewport that is double the size of the window, and you set this, then only the portion that fits within the window will be drawn, no automatic scaling is possible, even if your game scene is significantly larger than the window size.
 			</description>
 		</method>
-		<method name="viewport_set_scale_3d">
+		<method name="viewport_set_scaling_3d_mode">
+			<return type="void" />
+			<argument index="0" name="viewport" type="RID" />
+			<argument index="1" name="scaling_3d_mode" type="int" enum="RenderingServer.ViewportScaling3DMode" />
+			<description>
+				Sets scaling 3d mode. Bilinear scaling renders at different resolution to either undersample or supersample the viewport. FidelityFX Super Resolution 1.0, abbreviated to FSR, is an upscaling technology that produces high quality images at fast framerates by using a spatially aware upscaling algorithm. FSR is slightly more expensive than bilinear, but it produces significantly higher image quality. FSR should be used where possible.
+			</description>
+		</method>
+		<method name="viewport_set_scaling_3d_scale">
 			<return type="void" />
 			<argument index="0" name="viewport" type="RID" />
 			<argument index="1" name="scale" type="float" />
 			<description>
-				Sets the scale at which we render 3D contents.
+				Scales the 3D render buffer based on the viewport size uses an image filter specified in [enum ViewportScaling3DMode] to scale the output image to the full viewport size. Values lower than [code]1.0[/code] can be used to speed up 3D rendering at the cost of quality (undersampling). Values greater than [code]1.0[/code] are only valid for bilinear mode and can be used to improve 3D rendering quality at a high performance cost (supersampling). See also [enum ViewportMSAA] for multi-sample antialiasing, which is significantly cheaper but only smoothens the edges of polygons.
+				When using FSR upscaling, AMD recommends exposing the following values as preset options to users "Ultra Quality: 0.77", "Quality: 0.67", "Balanced: 0.59", "Performance: 0.5" instead of exposing the entire scale.
 			</description>
 		</method>
 		<method name="viewport_set_scenario">
@@ -3844,6 +3869,14 @@
 		<constant name="FOG_VOLUME_SHAPE_WORLD" value="2" enum="FogVolumeShape">
 			[FogVolume] will have no shape, will cover the whole world and will not be culled.
 		</constant>
+		<constant name="VIEWPORT_SCALING_3D_MODE_BILINEAR" value="0" enum="ViewportScaling3DMode">
+			Enables bilinear scaling on 3D viewports. The amount of scaling can be set using [member Viewport.scaling_3d_scale]. Values less then [code]1.0[/code] will result in undersampling while values greater than [code]1.0[/code] will result in supersampling. A value of [code]1.0[/code] disables scaling.
+		</constant>
+		<constant name="VIEWPORT_SCALING_3D_MODE_FSR" value="1" enum="ViewportScaling3DMode">
+			Enables FSR upscaling on 3D viewports. The amount of scaling can be set using [member Viewport.scaling_3d_scale]. Values less then [code]1.0[/code] will be result in the viewport being upscaled using FSR. Values greater than [code]1.0[/code] are not supported and bilinear supersampling will be used instead. A value of [code]1.0[/code] disables scaling.
+		</constant>
+		<constant name="VIEWPORT_SCALING_3D_MODE_MAX" value="2" enum="ViewportScaling3DMode">
+		</constant>
 		<constant name="VIEWPORT_UPDATE_DISABLED" value="0" enum="ViewportUpdateMode">
 			Do not update the viewport.
 		</constant>
diff --git a/doc/classes/Viewport.xml b/doc/classes/Viewport.xml
index d83645a8af..0418f29808 100644
--- a/doc/classes/Viewport.xml
+++ b/doc/classes/Viewport.xml
@@ -194,6 +194,14 @@
 		<member name="disable_3d" type="bool" setter="set_disable_3d" getter="is_3d_disabled" default="false">
 			Disable 3D rendering (but keep 2D rendering).
 		</member>
+		<member name="fsr_mipmap_bias" type="float" setter="set_fsr_mipmap_bias" getter="get_fsr_mipmap_bias" default="0.0">
+			Affects the final texture sharpness by reading from a lower or higher mipmap when using FSR. Mipmap bias does nothing when FSR is not being used. Negative values make textures sharper, while positive values make textures blurrier. This value is used to adjust the mipmap bias calculated internally which is based on the selected quality. The formula for this is [code]-log2(1.0 / scale) + mipmap_bias[/code]. This updates the rendering server's mipmap bias when called
+			To control this property on the root viewport, set the [member ProjectSettings.rendering/scaling_3d/fsr_mipmap_bias] project setting.
+		</member>
+		<member name="fsr_sharpness" type="float" setter="set_fsr_sharpness" getter="get_fsr_sharpness" default="0.2">
+			Determines how sharp the upscaled image will be when using the FSR upscaling mode. Sharpness halves with every whole number. Values go from 0.0 (sharpest) to 2.0. Values above 2.0 won't make a visible difference.
+			To control this property on the root viewport, set the [member ProjectSettings.rendering/scaling_3d/fsr_sharpness] project setting.
+		</member>
 		<member name="global_canvas_transform" type="Transform2D" setter="set_global_canvas_transform" getter="get_global_canvas_transform">
 			The global canvas transform of the viewport. The canvas transform is relative to this.
 		</member>
@@ -210,7 +218,7 @@
 		<member name="lod_threshold" type="float" setter="set_lod_threshold" getter="get_lod_threshold" default="1.0">
 		</member>
 		<member name="msaa" type="int" setter="set_msaa" getter="get_msaa" enum="Viewport.MSAA" default="0">
-			The multisample anti-aliasing mode. A higher number results in smoother edges at the cost of significantly worse performance. A value of 2 or 4 is best unless targeting very high-end systems. See also [member scale_3d] for supersampling, which provides higher quality but is much more expensive.
+			The multisample anti-aliasing mode. A higher number results in smoother edges at the cost of significantly worse performance. A value of 2 or 4 is best unless targeting very high-end systems. See also bilinear scaling 3d [member scaling_3d_mode] for supersampling, which provides higher quality but is much more expensive.
 		</member>
 		<member name="own_world_3d" type="bool" setter="set_use_own_world_3d" getter="is_using_own_world_3d" default="false">
 			If [code]true[/code], the viewport will use the [World3D] defined in [member world_3d].
@@ -218,9 +226,14 @@
 		<member name="physics_object_picking" type="bool" setter="set_physics_object_picking" getter="get_physics_object_picking" default="false">
 			If [code]true[/code], the objects rendered by viewport become subjects of mouse picking process.
 		</member>
-		<member name="scale_3d" type="float" setter="set_scale_3d" getter="get_scale_3d" default="1.0">
-			Scales the 3D render buffer based on the viewport size and displays the result with linear filtering. Values lower than [code]1.0[/code] can be used to speed up 3D rendering at the cost of quality (undersampling). Values greater than [code]1.0[/code] can be used to improve 3D rendering quality at a high performance cost (supersampling). See also [member msaa] for multi-sample antialiasing, which is significantly cheaper but only smoothens the edges of polygons.
-			To control this property on the root viewport, set the [member ProjectSettings.rendering/3d/viewport/scale] project setting.
+		<member name="scaling_3d_mode" type="int" setter="set_scaling_3d_mode" getter="get_scaling_3d_mode" enum="Viewport.Scaling3DMode" default="0">
+			Sets scaling 3d mode. Bilinear scaling renders at different resolution to either undersample or supersample the viewport. FidelityFX Super Resolution 1.0, abbreviated to FSR, is an upscaling technology that produces high quality images at fast framerates by using a spatially aware upscaling algorithm. FSR is slightly more expensive than bilinear, but it produces significantly higher image quality. FSR should be used where possible.
+			To control this property on the root viewport, set the [member ProjectSettings.rendering/scaling_3d/mode] project setting.
+		</member>
+		<member name="scaling_3d_scale" type="float" setter="set_scaling_3d_scale" getter="get_scaling_3d_scale" default="1.0">
+			Scales the 3D render buffer based on the viewport size uses an image filter specified in [member ProjectSettings.rendering/scaling_3d/mode] to scale the output image to the full viewport size. Values lower than [code]1.0[/code] can be used to speed up 3D rendering at the cost of quality (undersampling). Values greater than [code]1.0[/code] are only valid for bilinear mode and can be used to improve 3D rendering quality at a high performance cost (supersampling). See also [member ProjectSettings.rendering/anti_aliasing/quality/msaa] for multi-sample antialiasing, which is significantly cheaper but only smoothens the edges of polygons.
+			When using FSR upscaling, AMD recommends exposing the following values as preset options to users "Ultra Quality: 0.77", "Quality: 0.67", "Balanced: 0.59", "Performance: 0.5" instead of exposing the entire scale.
+			To control this property on the root viewport, set the [member ProjectSettings.rendering/scaling_3d/scale] project setting.
 		</member>
 		<member name="screen_space_aa" type="int" setter="set_screen_space_aa" getter="get_screen_space_aa" enum="Viewport.ScreenSpaceAA" default="0">
 			Sets the screen-space antialiasing method used. Screen-space antialiasing works by selectively blurring edges in a post-process shader. It differs from MSAA which takes multiple coverage samples while rendering objects. Screen-space AA methods are typically faster than MSAA and will smooth out specular aliasing, but tend to make scenes appear blurry.
@@ -306,6 +319,15 @@
 		<constant name="SHADOW_ATLAS_QUADRANT_SUBDIV_MAX" value="7" enum="ShadowAtlasQuadrantSubdiv">
 			Represents the size of the [enum ShadowAtlasQuadrantSubdiv] enum.
 		</constant>
+		<constant name="SCALING_3D_MODE_BILINEAR" value="0" enum="Scaling3DMode">
+			Enables bilinear scaling on 3D viewports. The amount of scaling can be set using [member scaling_3d_scale]. Values less then [code]1.0[/code] will result in undersampling while values greater than [code]1.0[/code] will result in supersampling. A value of [code]1.0[/code] disables scaling.
+		</constant>
+		<constant name="SCALING_3D_MODE_FSR" value="1" enum="Scaling3DMode">
+			Enables FSR upscaling on 3D viewports. The amount of scaling can be set using [member scaling_3d_scale]. Values less then [code]1.0[/code] will be result in the viewport being upscaled using FSR. Values greater than [code]1.0[/code] are not supported and bilinear supersampling will be used instead. A value of [code]1.0[/code] disables scaling.
+		</constant>
+		<constant name="SCALING_3D_MODE_MAX" value="2" enum="Scaling3DMode">
+			Represents the size of the [enum Scaling3DMode] enum.
+		</constant>
 		<constant name="MSAA_DISABLED" value="0" enum="MSAA">
 			Multisample antialiasing mode disabled. This is the default value, and is also the fastest setting.
 		</constant>