From c364bf61ec0c8fed865aa6fcfd79c2078fb6d356 Mon Sep 17 00:00:00 2001
From: Xaver Hugl <xaver.hugl@kde.org>
Date: Thu, 19 Feb 2026 16:45:21 +0100
Subject: [PATCH] staging/color-management: add Windows BT.2100 image
 description request

Just like with scRGB, Windows does (generally) not adjust BT.2100 images to
the viewing conditions of the user; this is instead expected to be handled by
the application or the display.
Adding this image description allows compositors to implement special handling
for all Windows HDR content, instead of being limited to scRGB in that regard.

Signed-off-by: Xaver Hugl <xaver.hugl@kde.org>
---
 .../color-management/color-management-v1.xml  | 50 ++++++++++++++++---
 1 file changed, 42 insertions(+), 8 deletions(-)

diff --git a/staging/color-management/color-management-v1.xml b/staging/color-management/color-management-v1.xml
index 774328d..b47e108 100644
--- a/staging/color-management/color-management-v1.xml
+++ b/staging/color-management/color-management-v1.xml
@@ -77,7 +77,7 @@
     only be done by creating a new major version of the extension.
   </description>
 
-  <interface name="wp_color_manager_v1" version="2">
+  <interface name="wp_color_manager_v1" version="3">
     <description summary="color manager singleton">
       A singleton global interface used for getting color management extensions
       for wl_surface and wl_output objects, and for creating client defined
@@ -164,6 +164,8 @@
       </entry>
       <entry name="windows_scrgb" value="7"
              summary="create_windows_scrgb request"/>
+      <entry name="windows_bt2100" value="8"
+             summary="create_windows_bt2100 request"/>
     </enum>
 
     <enum name="primaries">
@@ -595,9 +597,41 @@
       <arg name="reference"
            type="object" interface="wp_image_description_reference_v1"/>
     </request>
+
+    <request name="create_windows_bt2100" since="3">
+      <description summary="create Windows-BT.2100 image description object">
+        This creates a pre-defined image description for the so-called
+        Windows-BT.2100 stimulus encoding. This comes from the Windows 10
+        handling of its own definition of a BT.2100 color space for an HDR
+        screen driven in BT.2100/PQ signalling mode.
+
+        Windows-BT.2100 uses BT.2020 color primaries and white point.
+        The transfer characteristic is st2084_pq.
+
+        Windows-BT.2100 is generally displayed by Windows 10 without any
+        adjustments to the signal to account for viewing conditions.
+
+        The reference white level of Windows-BT.2100 is unknown. If a
+        reference white level must be assumed for compositor processing, it
+        should be 203 cd/m² of Report ITU-R BT.2408-7.
+
+        The target color volume of Windows-BT.2100 is unknown. The color gamut
+        may be anything up to BT.2100.
+
+        This request can be used when the compositor advertises
+        wp_color_manager_v1.feature.windows_bt2100.
+        Otherwise this request raises the protocol error unsupported_feature.
+
+        The resulting image description object does not allow get_information
+        request. The wp_image_description_v1.ready event shall be sent.
+      </description>
+
+      <arg name="image_description"
+           type="new_id" interface="wp_image_description_v1"/>
+      </request>
   </interface>
 
-  <interface name="wp_color_management_output_v1" version="2">
+  <interface name="wp_color_management_output_v1" version="3">
     <description summary="output color properties">
       A wp_color_management_output_v1 describes the color properties of an
       output.
@@ -667,7 +701,7 @@
     </request>
   </interface>
 
-  <interface name="wp_color_management_surface_v1" version="2">
+  <interface name="wp_color_management_surface_v1" version="3">
     <description summary="color management extension to a surface">
         A wp_color_management_surface_v1 allows the client to set the color
         space and HDR properties of a surface.
@@ -755,7 +789,7 @@
     </request>
   </interface>
 
-  <interface name="wp_color_management_surface_feedback_v1" version="2">
+  <interface name="wp_color_management_surface_feedback_v1" version="3">
     <description summary="color management extension to a surface">
         A wp_color_management_surface_feedback_v1 allows the client to get the
         preferred image description of a surface.
@@ -873,7 +907,7 @@
 
   </interface>
 
-  <interface name="wp_image_description_creator_icc_v1" version="2">
+  <interface name="wp_image_description_creator_icc_v1" version="3">
     <description summary="holder of image description ICC information">
       This type of object is used for collecting all the information required
       to create a wp_image_description_v1 object from an ICC file. A complete
@@ -989,7 +1023,7 @@
     </request>
   </interface>
 
-  <interface name="wp_image_description_creator_params_v1" version="2">
+  <interface name="wp_image_description_creator_params_v1" version="3">
     <description summary="holder of image description parameters">
       This type of object is used for collecting all the parameters required
       to create a wp_image_description_v1 object. A complete set of required
@@ -1363,7 +1397,7 @@
     </request>
   </interface>
 
-  <interface name="wp_image_description_v1" version="2">
+  <interface name="wp_image_description_v1" version="3">
     <description summary="Colorimetric image description">
       An image description carries information about the pixel color encoding
       and its intended display and viewing environment. The image description is
@@ -1510,7 +1544,7 @@
     </event>
   </interface>
 
-  <interface name="wp_image_description_info_v1" version="2">
+  <interface name="wp_image_description_info_v1" version="3">
     <description summary="Colorimetric image description information">
       Sends all matching events describing an image description object exactly
       once and finally sends the 'done' event.