commit cdf6cbc6595a675c01e112833d074eb0e22d037c
author Alec Mouri <alecmouri@google.com> Mon Nov 01 17:21:15 2021 -0700
committer Alec Mouri <alecmouri@google.com> Thu Dec 09 18:26:38 2021 -0800
tree 526f055612a7b94b3a9e2fa49692747bfe0f1d42
parent 2b1212b9b1d626a7d8da530429a660db33c4c7e6

End-to-end plumbing for dimming SDR layers

Model here is:
* HDR luminance is set to the current display brightness
* SDR luminance is set to the current SDR white point reported by
DisplayManager

Ideally we use scene-referred white points instead, so:
* PQ is always 10k nits
* HLG is always 1k nits
* Everything else is 150-200 nits

So relative dimming thresholds are fixed. But right now this is visually
less jarring (otherwise youtube UI will suddenly dim when autoplaying
HDR video).

Bug: 200310158
Test: Verified that plumbing sdr white point is sent to renderengine
Test: librenderengine_test
Test: libcompositionengine_test
Test: DataspaceUtils_test

Change-Id: I5bcea7941935c43e57cd5434e1ec69b41d31f2b4

services/surfaceflinger/DisplayHardware/HWC2.h

diff --git a/services/surfaceflinger/DisplayHardware/HWC2.h b/services/surfaceflinger/DisplayHardware/HWC2.h
index a65efb2..5e0ba06 100644
--- a/services/surfaceflinger/DisplayHardware/HWC2.h
+++ b/services/surfaceflinger/DisplayHardware/HWC2.h
@@ -146,7 +146,7 @@
             std::vector<hal::ContentType>*) const = 0;
     [[clang::warn_unused_result]] virtual hal::Error setContentType(hal::ContentType) = 0;
     [[clang::warn_unused_result]] virtual hal::Error getClientTargetProperty(
-            hal::ClientTargetProperty* outClientTargetProperty) = 0;
+            hal::ClientTargetProperty* outClientTargetProperty, float* outWhitePointNits) = 0;
 };
 
 namespace impl {
@@ -209,7 +209,8 @@
     hal::Error getSupportedContentTypes(
             std::vector<hal::ContentType>* outSupportedContentTypes) const override;
     hal::Error setContentType(hal::ContentType) override;
-    hal::Error getClientTargetProperty(hal::ClientTargetProperty* outClientTargetProperty) override;
+    hal::Error getClientTargetProperty(hal::ClientTargetProperty* outClientTargetProperty,
+                                       float* outWhitePointNits) override;
 
     // Other Display methods
     hal::HWDisplayId getId() const override { return mId; }
@@ -288,6 +289,9 @@
     // Composer HAL 2.4
     [[clang::warn_unused_result]] virtual hal::Error setLayerGenericMetadata(
             const std::string& name, bool mandatory, const std::vector<uint8_t>& value) = 0;
+
+    // AIDL HAL
+    [[clang::warn_unused_result]] virtual hal::Error setWhitePointNits(float whitePointNits) = 0;
 };
 
 namespace impl {
@@ -331,6 +335,9 @@
     hal::Error setLayerGenericMetadata(const std::string& name, bool mandatory,
                                        const std::vector<uint8_t>& value) override;
 
+    // AIDL HAL
+    hal::Error setWhitePointNits(float whitePointNits) override;
+
 private:
     // These are references to data owned by HWC2::Device, which will outlive
     // this HWC2::Layer, so these references are guaranteed to be valid for