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Update HDR output manual page based on development during the 4.7 dev cycle.
This commit is contained in:
Allen Pestaluky
@@ -3,8 +3,8 @@
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HDR output
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==========
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HDR output is a feature that enables presentation of High Dynamic Range (HDR) visuals on
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HDR-capable screens. HDR **output** is not to be confused with the internal HDR rendering that is
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HDR output is a feature that enables presentation of High Dynamic Range (HDR) visuals on
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HDR-capable screens. HDR **output** is not to be confused with the internal HDR rendering that is
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used by Godot for both Standard Dynamic Range (SDR) output and HDR output modes.
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Enabling HDR output in your project
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@@ -18,96 +18,134 @@ You can enable HDR output in any new or existing project using these steps:
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- Glow Blend Mode: Soft Light
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- Adjustments: Color Correction
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2. Configure the :ref:`Rendering Device Driver<class_ProjectSettings_property_rendering/rendering_device/driver>` project setting to the following:
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- macOS: metal
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- iOS: metal
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- Windows: d3d12
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3. Configure the :ref:`Display Server Driver.linuxbsd<class_ProjectSettings_property_display/display_server/driver.linuxbsd>`
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project setting to ``wayland`` and enable the :ref:`Prefer Wayland<class_EditorSettings_property_run/platforms/linuxbsd/prefer_wayland>`
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2. Configure the :ref:`Renderer<class_ProjectSettings_property_rendering/renderer/rendering_method>`
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project setting to ``mobile`` or ``forward_plus``.
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3. Configure the :ref:`Rendering Device Driver<class_ProjectSettings_property_rendering/rendering_device/driver>`
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advanced project setting to ``metal`` for iOS and ``d3d12`` for Windows.
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4. Configure the :ref:`Display Server Driver.linuxbsd<class_ProjectSettings_property_display/display_server/driver.linuxbsd>`
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advanced project setting to ``wayland`` and enable the :ref:`Prefer Wayland<class_EditorSettings_property_run/platforms/linuxbsd/prefer_wayland>`
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editor setting.
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4. Turn on the :ref:`HDR 2D<class_ProjectSettings_property_rendering/viewport/hdr_2d>` project
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5. Turn on the :ref:`HDR 2D<class_ProjectSettings_property_rendering/viewport/hdr_2d>` project
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setting and enable :ref:`use_hdr_2d<class_Viewport_property_use_hdr_2d>` for all
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:ref:`SubViewports <class_SubViewport>` and :ref:`Windows <class_Window>` that should support
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HDR output.
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5. Turn on the :ref:`Request HDR Output <class_ProjectSettings_property_display/window/hdr/request_hdr_output>`
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6. Turn on the :ref:`Request HDR Output <class_ProjectSettings_property_display/window/hdr/request_hdr_output>`
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project setting and enable :ref:`hdr_output_requested<class_Window_property_hdr_output_requested>`
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for all other :ref:`Windows <class_Window>` that should support HDR output.
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7. *[Optional]* Provide in-game HDR settings by copying the example from the
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`HDR output demo project <https://github.com/godotengine/godot-demo-projects/tree/master/misc/hdr_output>`__
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to your project.
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.. note::
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Some of these settings may already be configured correctly for HDR output in your project. For
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example, the Windows Rendering Device Driver is set to ``d3d12`` in projects created in Godot
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4.6 onwards, but will need to be changed if the project was created with an older version of
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Some of these settings may already be configured correctly for HDR output in your project. For
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example, the Windows Rendering Device Driver is set to ``d3d12`` in projects created in Godot
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4.6 onwards, but will need to be changed if the project was created with an older version of
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Godot.
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Using HDR output in Godot
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-------------------------
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Try out the `HDR output demo project <https://github.com/godotengine/godot-demo-projects/tree/master/misc/hdr_output>`__
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as a first step to using HDR output in Godot. This demo contains examples of the concepts
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described on this page and will help you ensure that your development environment is correctly
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configured for HDR output.
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HDR output in the Godot editor
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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The Godot editor will use HDR output for its main window when the :ref:`Request HDR Output <class_ProjectSettings_property_display/window/hdr/request_hdr_output>`
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project setting has been
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enabled. You can tell if your game is running in SDR or HDR output mode based on the text on the
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right side of game view toolbar: Your game is running in HDR mode when the text "HDR" appears next
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to the window size.
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.. image:: img/rendering_hdr_output_game_view.webp
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The number in parentheses next to the "HDR" text is the current :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`
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which is described in the following sections. You can toggle the game's
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:ref:`Window.hdr_output_requested<class_Window_property_hdr_output_requested>` property in the game
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window options menu:
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.. image:: img/rendering_hdr_output_game_window_options.webp
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HDR output fundamentals
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-----------------------
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Godot uses the `Extended Dynamic Range (EDR) <https://developer.apple.com/videos/play/wwdc2021/10161/>`__
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paradigm for HDR output. While SDR
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output allows color component values between ``0.0`` and ``1.0`` to be displayed, HDR output
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allows values higher than ``1.0``. The maximum value that can be displayed is provided by
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:ref:`Window.get_output_max_linear_value()<class_Window_method_get_output_max_linear_value>` and
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paradigm for HDR output. While SDR
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output allows color component values between ``0.0`` and ``1.0`` to be displayed, HDR output
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allows values higher than ``1.0``. The maximum value that can be displayed is provided by
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:ref:`Window.get_output_max_linear_value()<class_Window_method_get_output_max_linear_value>` and
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this method is valid when using SDR or HDR.
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.. image:: img/rendering_hdr_output_fundamentals.webp
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.. note::
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These graphs are presented as SDR images that do not contain any HDR color. To compensate for
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this limitation, the grayscale bars along each axis have a glow effect applied to represent
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values that are outside of the SDR range. The "output max value" in this graph represents the
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maximum linear color component value returned by
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These graphs are presented as SDR images that do not contain any HDR color. To compensate for
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this limitation, the grayscale bars along each axis have a glow effect applied to represent
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values that are outside of the SDR range. The "output max value" in this graph represents the
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maximum linear color component value returned by
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:ref:`Window.get_output_max_linear_value()<class_Window_method_get_output_max_linear_value>`.
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Designing for HDR output
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------------------------
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There are two primary approaches to make the most of HDR output: using the
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:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` and using the
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:ref:`class_WorldEnvironment` node.
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:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` and using
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tonemapping.
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While both approaches can be used in the same project, the
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:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` should generally
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not be used in scenes that are affected by a :ref:`class_WorldEnvironment`. The
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:ref:`Viewport.own_world_3d<class_Viewport_property_own_world_3d>` property can be used to
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separate which :ref:`Viewports<class_Viewport>` are affected by a :ref:`class_WorldEnvironment`.
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While both approaches can be used in the same project, tonemapping should be used to produce HDR
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output from a :ref:`Viewport<class_Viewport>` that uses lighting that exceeds the capabilities of an
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SDR screen, indirect lighting, global illumination, emissive materials, post-processing effects, or
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any other techniques that make use of the colors values in the scene.
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The :ref:`output max linear value<class_Window_method_get_output_max_linear_value>` should only be
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used to present colors directly to the screen without tonemapping and without influencing lighting,
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post-processing effects, or surrounding color. This makes the
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:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` well suited for
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:ref:`CanvasItems<class_CanvasItem>` or unshaded materials in a scene that has no lighting or basic
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lighting that otherwise does not exceed the capabilities of an SDR screen.
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The :ref:`Viewport.own_world_3d<class_Viewport_property_own_world_3d>` property can be used to
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separate which :ref:`Viewports<class_Viewport>` are affected by tonemapping and other
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:ref:`class_WorldEnvironment` effects.
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Using output max linear value
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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In a traditional SDR-only game, the brightest presentation of a color is limited by either the
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red, green, or blue component of the color reaching a maximum of ``1.0``. When using a modern HDR
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screen this limitation no longer applies and color components above ``1.0`` can be accurately
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presented. Godot provides the maximum color component value that can be presented by the screen
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through the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`. This
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value can be used in both SDR and HDR, which makes it easy to build your game for both output
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In a traditional SDR-only game, the brightest presentation of a color is limited by either the
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red, green, or blue component of the color reaching a maximum of ``1.0``. When using a modern HDR
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screen this limitation no longer applies and color components above ``1.0`` can be accurately
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presented. Godot provides the maximum color component value that can be presented by the screen
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through the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`. This
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value can be used in both SDR and HDR, which makes it easy to build your game for both output
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modes without needing to change behavior based on whether or not HDR output is enabled.
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The :ref:`output max linear value<class_Window_method_get_output_max_linear_value>` may change
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often as the player adjusts their device brightness, enables or disables HDR output on their
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device, or moves the game window between screens, so it's important to retrieve this value every
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frame. The value will always equal ``1.0`` in SDR mode and may also equal ``1.0`` when HDR output
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The :ref:`output max linear value<class_Window_method_get_output_max_linear_value>` may change
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often as the player adjusts their device brightness, enables or disables HDR output on their
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device, or moves the game window between screens, so it's important to retrieve this value every
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frame or use the :ref:`output max linear value changed<class_Window_signal_output_max_linear_value_changed>`
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signal. The value will always equal ``1.0`` in SDR mode and may also equal ``1.0`` when HDR output
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is enabled and the player has adjusted their screen to its maximum brightness.
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It is best to use this :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`
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with "highlights" and special effects that
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are either brief or involve a small portion of the screen; if the majority of the screen is
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presented at this maximum brightness for more than a short time, it will cause the game to appear
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uncomfortably bright, as if the game is ignoring the device brightness setting. You may also find
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that some effects look best when limited to a maximum linear value that is greater than ``1.0``,
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but less than the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`.
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with "highlights" and special effects that
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are either brief or involve a small portion of the screen; if the majority of the screen is
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presented at this maximum brightness for more than a short time, it will cause the game to appear
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uncomfortably bright, as if the game is ignoring the device brightness setting. You may also find
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that some effects look best when limited to a maximum linear value that is greater than ``1.0``,
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but less than the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`.
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You can read more about how it is sometimes desirable to limit the maximum HDR value in the
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`HDR and User Interfaces <https://android-developers.googleblog.com/2025/09/hdr-and-user-interfaces.html>`__
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post of the Android Developers Blog.
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Transforming a color to be the brightest the screen can present can be done with a script. When
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working with :ref:`class_CanvasItem`, it may be convenient to apply the resulting modified color
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to the :ref:`modulate<class_canvasitem_property_modulate>` or
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:ref:`self_modulate<class_canvasitem_property_self_modulate>` property with the base color of the
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:ref:`class_CanvasItem` set to :ref:`white<class_color_constant_white>`. The following script
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Transforming a color to be the brightest the screen can present can be done with a script. When
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working with :ref:`class_CanvasItem`, it may be convenient to apply the resulting modified color
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to the :ref:`modulate<class_canvasitem_property_modulate>` or
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:ref:`self_modulate<class_canvasitem_property_self_modulate>` property with the base color of the
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:ref:`class_CanvasItem` set to :ref:`white<class_color_constant_white>`. The following script
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demonstrates this:
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.. tabs::
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@@ -122,20 +160,29 @@ demonstrates this:
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@export_range(0, 20, 0.1, "or_less", "or_greater") var max_linear_value_limit: float = -1.0
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func _process(_delta: float) -> void:
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func _enter_tree() -> void:
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var window: Window = get_window()
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window.output_max_linear_value_changed.connect(_on_output_max_linear_value_changed)
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_on_output_max_linear_value_changed(window.get_output_max_linear_value())
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func _exit_tree() -> void:
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get_window().output_max_linear_value_changed.disconnect(_on_output_max_linear_value_changed)
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func _on_output_max_linear_value_changed(output_max_linear_value: float) -> void:
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# Adjust the brightness of color to be the brightest possible, regardless
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# of SDR or HDR output, but no brighter than max_linear_value_limit.
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var max_linear_value = get_window().get_output_max_linear_value()
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if max_linear_value_limit >= 0.0:
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max_linear_value = minf(max_linear_value, max_linear_value_limit)
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self_modulate = normalize_color(sdr_self_modulate, max_linear_value)
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output_max_linear_value = minf(output_max_linear_value, max_linear_value_limit)
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self_modulate = normalize_color(sdr_self_modulate, output_max_linear_value)
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func normalize_color(srgb_color, max_linear_value = 1.0):
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func normalize_color(srgb_color, output_max_linear_value = 1.0):
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# Color must be linear-encoded to use math operations.
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var linear_color = srgb_color.srgb_to_linear()
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var max_rgb_value = maxf(linear_color.r, maxf(linear_color.g, linear_color.b))
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var brightness_scale = max_linear_value / max_rgb_value
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var brightness_scale = output_max_linear_value / max_rgb_value
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linear_color *= brightness_scale
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# Undo changes to the alpha channel, which should not be modified.
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linear_color.a = srgb_color.a
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@@ -144,29 +191,30 @@ demonstrates this:
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return linear_color.linear_to_srgb()
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Using a WorldEnvironment node
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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Using Tonemapping
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^^^^^^^^^^^^^^^^^
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To produce HDR output using a :ref:`class_WorldEnvironment`, your scenes will need color values
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that exceed what an SDR screen can present, so it is important to use a tonemapper like
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:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` or
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:ref:`AgX<class_Environment_constant_tone_mapper_agx>` to handle display of bright scene values on
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both SDR and HDR screens.
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To produce HDR output without using the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`
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your scenes will need color values
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that exceed what an SDR screen can present, so it is important to use a tonemapper like
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:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` or
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:ref:`AgX<class_Environment_constant_tone_mapper_agx>` to handle display of these bright scene
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values on both SDR and HDR screens.
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**Tonemapping and HDR**
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The primary role of a tonemapper is to reduce the dynamic range of a natural scene with a very
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high dynamic range of brightness to a smaller dynamic range that can be presented on a screen.
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The primary role of a tonemapper is to reduce the dynamic range of a natural scene with a very
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high dynamic range of brightness to a smaller dynamic range that can be presented on a screen.
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Tonemappers in Godot use the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`
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to determine the output range that the screen is capable of presenting. For example, with the
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:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` tonemapper in Godot, linear
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to determine the output range that the screen is capable of presenting. For example, with the
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:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` tonemapper in Godot, linear
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scene values in the range of ``0.0`` to :ref:`tonemap white<class_Environment_property_tonemap_white>`
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are mapped to an output range of ``0.0`` to
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are mapped to an output range of ``0.0`` to
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:ref:`output max linear value<class_Window_method_get_output_max_linear_value>`.
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.. image:: img/rendering_hdr_output_sdr_tonemap.webp
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With this approach, you can adjust :ref:`tonemap white<class_Environment_property_tonemap_white>`
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With this approach, you can adjust :ref:`tonemap white<class_Environment_property_tonemap_white>`
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to be sure that any linear scene value below :ref:`tonemap white<class_Environment_property_tonemap_white>`
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will be shown without clipping. This ensures that details are not lost when presenting the image
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on a screen with a lower dynamic range than the original scene.
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@@ -178,47 +226,44 @@ is fixed at ``1.0``, this behavior is dynamic with HDR based on the capabilities
|
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.. image:: img/rendering_hdr_output_hdr_tonemap.webp
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As shown in the graphs above, the
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:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` tonemapper will behave the same
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As shown in the graphs above, the
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:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` tonemapper will behave the same
|
||||
as the :ref:`Linear<class_Environment_constant_tone_mapper_linear>` tonemapper when
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:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` is equal to or higher than
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||||
:ref:`tonemap white<class_Environment_property_tonemap_white>`. This allows for accurate color
|
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reproduction on HDR screens that are capable of reproducing the original brighter scene values.
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When :ref:`output max linear value<class_Window_method_get_output_max_linear_value>` has increased
|
||||
to be higher than :ref:`tonemap white<class_Environment_property_tonemap_white>`, tonemap white
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||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` is equal to or higher than
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||||
:ref:`tonemap white<class_Environment_property_tonemap_white>`. This allows for accurate color
|
||||
reproduction on HDR screens that are capable of reproducing the original brighter scene values.
|
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When :ref:`output max linear value<class_Window_method_get_output_max_linear_value>` has increased
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to be higher than :ref:`tonemap white<class_Environment_property_tonemap_white>`, tonemap white
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will be adjusted to match this output max linear value.
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||||
The :ref:`AgX<class_Environment_constant_tone_mapper_agx>` tonemapper behaves similar to
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||||
:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` in this way, but its
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||||
:ref:`tonemap white<class_Environment_property_tonemap_agx_white>` is always multiplied by
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||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>`. The
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:ref:`Linear<class_Environment_constant_tone_mapper_linear>` tonemapper applies no tonemapping at
|
||||
The :ref:`AgX<class_Environment_constant_tone_mapper_agx>` tonemapper behaves similar to
|
||||
:ref:`Reinhard<class_Environment_constant_tone_mapper_reinhardt>` in this way, but its
|
||||
:ref:`tonemap white<class_Environment_property_tonemap_agx_white>` is always multiplied by
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>`. The
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:ref:`Linear<class_Environment_constant_tone_mapper_linear>` tonemapper applies no tonemapping at
|
||||
all; its :ref:`tonemap white<class_Environment_property_tonemap_white>` equals
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||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` in all scenarios. The
|
||||
:ref:`Filmic<class_Environment_constant_tone_mapper_filmic>` and
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` in all scenarios. The
|
||||
:ref:`Filmic<class_Environment_constant_tone_mapper_filmic>` and
|
||||
:ref:`ACES<class_Environment_constant_tone_mapper_aces>` tonemappers ignore
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` entirely and always produce an
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` entirely and always produce an
|
||||
image in the SDR range.
|
||||
|
||||
Mixing output max linear value and the WorldEnvironment node
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
Why not mix output max linear value with other techniques?
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
The :ref:`output max linear value<class_Window_method_get_output_max_linear_value>` should
|
||||
generally not be used in scenes that are affected by a :ref:`class_WorldEnvironment`. This is
|
||||
because a number of effects of :ref:`Environment<class_environment>` expect stable scene values
|
||||
that do not change based on the screen capabilities. For example, the strength of the glow effect
|
||||
is directly influenced by the brightness of the scene. If the scene brightness changes based on
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>`, then the glow
|
||||
Tonemapping, indirect lighting, global illumination, and post-processing effects all depend on
|
||||
stable scene color values to produce consistent and predictable results in both SDR and HDR modes.
|
||||
If a developer uses these types of techniques with a scene that has color values that change based
|
||||
on :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`, the results will
|
||||
no longer be similar for screens with different capabilities.
|
||||
|
||||
For example, the strength of the glow effect
|
||||
is directly influenced by the brightness of the scene. If the scene brightness changes based on
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>`, then the glow
|
||||
strength will change as well: a larger
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` will produce a
|
||||
stronger glow effect, which is generally an undesirable behavior.
|
||||
|
||||
An exception to this rule is to change the
|
||||
:ref:`background mode<class_Environment_property_background_mode>` through a :ref:`class_WorldEnvironment` with a
|
||||
:ref:`Linear<class_Environment_constant_tone_mapper_linear>` tonemapper because the
|
||||
:ref:`Linear<class_Environment_constant_tone_mapper_linear>` tonemap mode disables tonemapping and
|
||||
background rendering is not affected by the brightness of scene values.
|
||||
|
||||
Absolute luminance values
|
||||
-------------------------
|
||||
|
||||
@@ -228,12 +273,12 @@ is calculated based on the reference white luminance and the maximum luminance o
|
||||
Reference white luminance
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
The reference white luminance, or reference luminance for short, represents the brightest possible
|
||||
SDR white value. When a user changes the brightness setting of the device that is producing the
|
||||
video signal, such as a desktop computer, laptop, or smartphone, they are simply adjusting their
|
||||
reference luminance. On a smartphone this change may happen automatically via the smartphone's
|
||||
automatic screen brightness feature and also happens when the user manually adjusts their screen
|
||||
brightness. On desktop or laptop computers, there are different ways to adjust this reference
|
||||
The reference white luminance, or reference luminance for short, represents the brightest possible
|
||||
SDR white value. When a user changes the brightness setting of the device that is producing the
|
||||
video signal, such as a desktop computer, laptop, or smartphone, they are simply adjusting their
|
||||
reference luminance. On a smartphone this change may happen automatically via the smartphone's
|
||||
automatic screen brightness feature and also happens when the user manually adjusts their screen
|
||||
brightness. On desktop or laptop computers, there are different ways to adjust this reference
|
||||
luminance depending on the operating system.
|
||||
|
||||
This value is typically around 100 to 300 nits and is always represented by an
|
||||
@@ -243,41 +288,41 @@ This value may also be referred to as "paper white" or the "SDR white level".
|
||||
Maximum luminance
|
||||
^^^^^^^^^^^^^^^^^
|
||||
|
||||
The maximum luminance is a property of an HDR screen. This value may be anywhere from 250 to 2,000
|
||||
The maximum luminance is a property of an HDR screen. This value may be anywhere from 250 to 2,000
|
||||
nits or beyond.
|
||||
|
||||
Although this value is a property of the screen hardware and is expected to not change, some
|
||||
devices dynamically adapt this value to work within the constraints of the platform. For example,
|
||||
the reported maximum luminance of Windows laptops with built-in HDR screens will change as the
|
||||
user adjusts their laptop screen brightness while the reported reference luminance remains
|
||||
Although this value is a property of the screen hardware and is expected to not change, some
|
||||
devices dynamically adapt this value to work within the constraints of the platform. For example,
|
||||
the reported maximum luminance of Windows laptops with built-in HDR screens will change as the
|
||||
user adjusts their laptop screen brightness while the reported reference luminance remains
|
||||
constant.
|
||||
|
||||
Output max linear value in practice
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
When in HDR mode, the :ref:`output max linear value<class_Window_method_get_output_max_linear_value>`
|
||||
will increase as the user decreases their
|
||||
reference luminance because more HDR headroom becomes available. Similarly, as the user increases
|
||||
will increase as the user decreases their
|
||||
reference luminance because more HDR headroom becomes available. Similarly, as the user increases
|
||||
their reference luminance, they will have less HDR headroom available and
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` will decrease. In some cases when using
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` will decrease. In some cases when using
|
||||
HDR mode with the highest reference luminance,
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` will equal ``1.0``, matching SDR behavior,
|
||||
:ref:`output max linear value<class_Window_method_get_output_max_linear_value>` will equal ``1.0``, matching SDR behavior,
|
||||
because no HDR headroom is available.
|
||||
|
||||
Not all screens are equal
|
||||
-------------------------
|
||||
|
||||
SDR standards were designed to match the capabilities of existing screens that were commonly used
|
||||
around the world. HDR standards have been intentionally written with the opposite approach: they
|
||||
SDR standards were designed to match the capabilities of existing screens that were commonly used
|
||||
around the world. HDR standards have been intentionally written with the opposite approach: they
|
||||
are designed to utilize the capabilities of an ideal screen that is not yet widely available.
|
||||
|
||||
In practice, this means that common HDR screens may perform their own internal tonemapping, gamut
|
||||
mapping, or dynamic tonemapping (DTM) to support content that extends to a wider gamut and
|
||||
luminance range than what the physical hardware can achieve. Some screens are not capable of
|
||||
presenting very bright color values that fill more than a small (1% to 10%) portion of the
|
||||
screen and will dim the entire image or part of the image temporarily when this happens. These
|
||||
features may produce colors that are not representative of other screens so it's best to disable
|
||||
them, if possible, when developing your HDR game. You may be able to disable some or all of these
|
||||
features by enabling the HGiG mode on your screen or setting the screen's mode to "clip" and/or
|
||||
"stable". Some HDR screens may present dark or saturated colors differently than others; this
|
||||
In practice, this means that common HDR screens may perform their own internal tonemapping, gamut
|
||||
mapping, or dynamic tonemapping (DTM) to support content that extends to a wider gamut and
|
||||
luminance range than what the physical hardware can achieve. Some screens are not capable of
|
||||
presenting very bright color values that fill more than a small (1% to 10%) portion of the
|
||||
screen and will dim the entire image or part of the image temporarily when this happens. These
|
||||
features may produce colors that are not representative of other screens so it's best to disable
|
||||
them, if possible, when developing your HDR game. You may be able to disable some or all of these
|
||||
features by enabling the HGiG mode on your screen or setting the screen's mode to "clip" and/or
|
||||
"stable". Some HDR screens may present dark or saturated colors differently than others; this
|
||||
difference in appearance is often the result of the screen technologies.
|
||||
|
||||
BIN
tutorials/rendering/img/rendering_hdr_output_game_view.webp
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tutorials/rendering/img/rendering_hdr_output_game_view.webp
Normal file
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|
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|
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Reference in New Issue
Block a user