Color management (ICC profiles) and HDR support (like GNOME 50, Hyprland, Niri)(wp_color_management v2)DRM Color Pipeline API

[abhiramh23]

Currently, mangowc lacks color management and HDR capabilities. This request proposes adding config-file-driven color management and HDR support similar to what's available in Hyprland (ICC profiles, multiple color spaces), Niri (gradient color spaces, wlr-output-management), and GNOME 50 (wp_color_management v2, SDR native mode, HDR screen sharing).

Kernel Foundation: Linux 6.19/7.0 Now Has the Infrastructure

DRM Color Pipeline API

· Merged in Linux 6.19, backed by Valve, Igalia, AMD, and others
· Provides a standardized kernel API for color pipeline operations
· Allows compositors to describe exact color transformations to the kernel
· Includes support for:
· 1D curves (EOTF, inverse EOTF, OETF)
· 3x4 Color Transformation Matrices (CTM)
· 1D LUTs and 3D LUTs (17^3 tetrahedrally interpolated)
· PQ (Perceptual Quantizer) and HLG (Hybrid Log-Gamma) for HDR
· BT.2020/BT.709 color spaces

Driver Support in 6.19/7.0

· AMDGPU: Full color pipeline support for DCN 3.0+ GPUs
· Intel: i915 and Xe drivers with plane color management (Xe3P support for Nova Lake)
· NVIDIA: The open-source Nova driver has begun preparing for future GPU support
· VKMS: Virtual driver for testing, ensuring API stability

Wayland Color Protocol Matures

· wp_color_management v2 protocol (as used in GNOME 50) enables client-side color description
· Mesa/Vulkan now implements the Wayland color management protocol

Vulkan HDR Metadata on Wayland

· Vulkan driver added VK_EXT_hdr_metadata support under Wayland
· Allows Vulkan applications to pass HDR metadata to displays
· Essential for accurate tone mapping in games and creative apps

Reference Implementations

Hyprland Approach

Hyprland supports ICC profiles and multiple color spaces including sRGB, BT.2020, and DCI-P3. Key features:

· Per-monitor ICC profile loading via hyprctl keyword monitor "DP-1,preferred,auto,1.0,icc_profile:/path/profile.icc"
· Application-specific color spaces via windowrules: windowrule = colorspace adobe-rgb,^(gimp)$
· HDR metadata support with PQ and HLG transfer functions
· EDID fallback when no ICC profile is specified
· NVIDIA note: Works but requires beta drivers for HDR

Niri Approach

Niri implements wlr-output-management for external tools and supports gradient color spaces:

· Gradient interpolation in srgb, srgb-linear, oklab, and oklch with hue control
· Configuration-driven approach with INI-like sections
· Background color per output for fallback

GNOME 50 Approach

GNOME 50 (RC) includes wp_color_management v2 protocol support:

· SDR native color mode for wide-gamut displays
· HDR screen sharing with PipeWire streams advertising FP16/RGB10 formats using BT.2020 + PQ
· Per-output ICC profile assignment via Settings > Color
· NVIDIA note: Mutter 47.rc added EGLDevice fixes for older GeForce cards

Proposed Implementation

Wayland Protocol Support

· Implement wp_color_management v2 (as in GNOME 50)
· Support wlr-output-management for external tools (as in Niri)
· Leverage Linux 6.19's DRM Color Pipeline API for kernel-level color operations

SDR Native Mode

Add a sdr_mode option for wide-gamut displays that don't need full HDR, similar to GNOME 50's SDR native color mode.