Wire-up colorMode="hdr"
Fow now it uses a fixed white point of 150nits
TBD if this is disabled or adjusted
Test: Demo app
Change-Id: Iac13597b3d7633fdef3feaf7ec1da0c27c87904c
diff --git a/libs/hwui/ColorMode.h b/libs/hwui/ColorMode.h
new file mode 100644
index 0000000..6d387f9
--- /dev/null
+++ b/libs/hwui/ColorMode.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+namespace android::uirenderer {
+
+// Must match the constants in ActivityInfo.java
+enum class ColorMode {
+ // SRGB means HWUI will produce buffer in SRGB color space.
+ Default = 0,
+ // WideColorGamut selects the most optimal colorspace & format for the device's display
+ // Most commonly DisplayP3 + RGBA_8888 currently.
+ WideColorGamut = 1,
+ // HDR Rec2020 + F16
+ Hdr = 2,
+ // HDR Rec2020 + 1010102
+ Hdr10 = 3,
+};
+
+} // namespace android::uirenderer
diff --git a/libs/hwui/jni/android_graphics_HardwareRenderer.cpp b/libs/hwui/jni/android_graphics_HardwareRenderer.cpp
index 42743db..7d6875f 100644
--- a/libs/hwui/jni/android_graphics_HardwareRenderer.cpp
+++ b/libs/hwui/jni/android_graphics_HardwareRenderer.cpp
@@ -143,11 +143,10 @@
}
static jlong android_view_ThreadedRenderer_createProxy(JNIEnv* env, jobject clazz,
- jboolean translucent, jboolean isWideGamut, jlong rootRenderNodePtr) {
+ jboolean translucent, jlong rootRenderNodePtr) {
RootRenderNode* rootRenderNode = reinterpret_cast<RootRenderNode*>(rootRenderNodePtr);
ContextFactoryImpl factory(rootRenderNode);
RenderProxy* proxy = new RenderProxy(translucent, rootRenderNode, &factory);
- proxy->setWideGamut(isWideGamut);
return (jlong) proxy;
}
@@ -218,10 +217,10 @@
proxy->setOpaque(opaque);
}
-static void android_view_ThreadedRenderer_setWideGamut(JNIEnv* env, jobject clazz,
- jlong proxyPtr, jboolean wideGamut) {
+static void android_view_ThreadedRenderer_setColorMode(JNIEnv* env, jobject clazz,
+ jlong proxyPtr, jint colorMode) {
RenderProxy* proxy = reinterpret_cast<RenderProxy*>(proxyPtr);
- proxy->setWideGamut(wideGamut);
+ proxy->setColorMode(static_cast<ColorMode>(colorMode));
}
static int android_view_ThreadedRenderer_syncAndDrawFrame(JNIEnv* env, jobject clazz,
@@ -659,7 +658,7 @@
(void*)android_view_ThreadedRenderer_setProcessStatsBuffer},
{"nGetRenderThreadTid", "(J)I", (void*)android_view_ThreadedRenderer_getRenderThreadTid},
{"nCreateRootRenderNode", "()J", (void*)android_view_ThreadedRenderer_createRootRenderNode},
- {"nCreateProxy", "(ZZJ)J", (void*)android_view_ThreadedRenderer_createProxy},
+ {"nCreateProxy", "(ZJ)J", (void*)android_view_ThreadedRenderer_createProxy},
{"nDeleteProxy", "(J)V", (void*)android_view_ThreadedRenderer_deleteProxy},
{"nLoadSystemProperties", "(J)Z",
(void*)android_view_ThreadedRenderer_loadSystemProperties},
@@ -671,7 +670,7 @@
{"nSetLightAlpha", "(JFF)V", (void*)android_view_ThreadedRenderer_setLightAlpha},
{"nSetLightGeometry", "(JFFFF)V", (void*)android_view_ThreadedRenderer_setLightGeometry},
{"nSetOpaque", "(JZ)V", (void*)android_view_ThreadedRenderer_setOpaque},
- {"nSetWideGamut", "(JZ)V", (void*)android_view_ThreadedRenderer_setWideGamut},
+ {"nSetColorMode", "(JI)V", (void*)android_view_ThreadedRenderer_setColorMode},
{"nSyncAndDrawFrame", "(J[JI)I", (void*)android_view_ThreadedRenderer_syncAndDrawFrame},
{"nDestroy", "(JJ)V", (void*)android_view_ThreadedRenderer_destroy},
{"nRegisterAnimatingRenderNode", "(JJ)V",
diff --git a/libs/hwui/pipeline/skia/SkiaOpenGLPipeline.cpp b/libs/hwui/pipeline/skia/SkiaOpenGLPipeline.cpp
index 24a6228..389fe7e 100644
--- a/libs/hwui/pipeline/skia/SkiaOpenGLPipeline.cpp
+++ b/libs/hwui/pipeline/skia/SkiaOpenGLPipeline.cpp
@@ -87,6 +87,8 @@
// Note: The default preference of pixel format is RGBA_8888, when other
// pixel format is available, we should branch out and do more check.
fboInfo.fFormat = GL_RGBA8;
+ } else if (colorType == kRGBA_1010102_SkColorType) {
+ fboInfo.fFormat = GL_RGB10_A2;
} else {
LOG_ALWAYS_FATAL("Unsupported color type.");
}
diff --git a/libs/hwui/pipeline/skia/SkiaPipeline.cpp b/libs/hwui/pipeline/skia/SkiaPipeline.cpp
index 89a1c71..6dd3698 100644
--- a/libs/hwui/pipeline/skia/SkiaPipeline.cpp
+++ b/libs/hwui/pipeline/skia/SkiaPipeline.cpp
@@ -35,6 +35,7 @@
#include "VectorDrawable.h"
#include "thread/CommonPool.h"
#include "tools/SkSharingProc.h"
+#include "utils/Color.h"
#include "utils/String8.h"
#include "utils/TraceUtils.h"
@@ -587,14 +588,23 @@
void SkiaPipeline::setSurfaceColorProperties(ColorMode colorMode) {
mColorMode = colorMode;
- if (colorMode == ColorMode::SRGB) {
- mSurfaceColorType = SkColorType::kN32_SkColorType;
- mSurfaceColorSpace = SkColorSpace::MakeSRGB();
- } else if (colorMode == ColorMode::WideColorGamut) {
- mSurfaceColorType = DeviceInfo::get()->getWideColorType();
- mSurfaceColorSpace = DeviceInfo::get()->getWideColorSpace();
- } else {
- LOG_ALWAYS_FATAL("Unreachable: unsupported color mode.");
+ switch (colorMode) {
+ case ColorMode::Default:
+ mSurfaceColorType = SkColorType::kN32_SkColorType;
+ mSurfaceColorSpace = SkColorSpace::MakeSRGB();
+ break;
+ case ColorMode::WideColorGamut:
+ mSurfaceColorType = DeviceInfo::get()->getWideColorType();
+ mSurfaceColorSpace = DeviceInfo::get()->getWideColorSpace();
+ break;
+ case ColorMode::Hdr:
+ mSurfaceColorType = SkColorType::kRGBA_F16_SkColorType;
+ mSurfaceColorSpace = SkColorSpace::MakeRGB(GetPQSkTransferFunction(), SkNamedGamut::kRec2020);
+ break;
+ case ColorMode::Hdr10:
+ mSurfaceColorType = SkColorType::kRGBA_1010102_SkColorType;
+ mSurfaceColorSpace = SkColorSpace::MakeRGB(GetPQSkTransferFunction(), SkNamedGamut::kRec2020);
+ break;
}
}
diff --git a/libs/hwui/pipeline/skia/SkiaPipeline.h b/libs/hwui/pipeline/skia/SkiaPipeline.h
index 8341164..100bfb6 100644
--- a/libs/hwui/pipeline/skia/SkiaPipeline.h
+++ b/libs/hwui/pipeline/skia/SkiaPipeline.h
@@ -50,7 +50,7 @@
bool createOrUpdateLayer(RenderNode* node, const DamageAccumulator& damageAccumulator,
ErrorHandler* errorHandler) override;
- void setSurfaceColorProperties(renderthread::ColorMode colorMode) override;
+ void setSurfaceColorProperties(ColorMode colorMode) override;
SkColorType getSurfaceColorType() const override { return mSurfaceColorType; }
sk_sp<SkColorSpace> getSurfaceColorSpace() override { return mSurfaceColorSpace; }
@@ -76,7 +76,7 @@
renderthread::RenderThread& mRenderThread;
- renderthread::ColorMode mColorMode = renderthread::ColorMode::SRGB;
+ ColorMode mColorMode = ColorMode::Default;
SkColorType mSurfaceColorType;
sk_sp<SkColorSpace> mSurfaceColorSpace;
diff --git a/libs/hwui/renderthread/CanvasContext.cpp b/libs/hwui/renderthread/CanvasContext.cpp
index a362bd2..13d544c 100644
--- a/libs/hwui/renderthread/CanvasContext.cpp
+++ b/libs/hwui/renderthread/CanvasContext.cpp
@@ -174,7 +174,10 @@
} else {
mNativeSurface = nullptr;
}
+ setupPipelineSurface();
+}
+void CanvasContext::setupPipelineSurface() {
bool hasSurface = mRenderPipeline->setSurface(
mNativeSurface ? mNativeSurface->getNativeWindow() : nullptr, mSwapBehavior);
@@ -184,7 +187,7 @@
mFrameNumber = -1;
- if (window != nullptr && hasSurface) {
+ if (mNativeSurface != nullptr && hasSurface) {
mHaveNewSurface = true;
mSwapHistory.clear();
// Enable frame stats after the surface has been bound to the appropriate graphics API.
@@ -239,9 +242,9 @@
mOpaque = opaque;
}
-void CanvasContext::setWideGamut(bool wideGamut) {
- ColorMode colorMode = wideGamut ? ColorMode::WideColorGamut : ColorMode::SRGB;
- mRenderPipeline->setSurfaceColorProperties(colorMode);
+void CanvasContext::setColorMode(ColorMode mode) {
+ mRenderPipeline->setSurfaceColorProperties(mode);
+ setupPipelineSurface();
}
bool CanvasContext::makeCurrent() {
diff --git a/libs/hwui/renderthread/CanvasContext.h b/libs/hwui/renderthread/CanvasContext.h
index 0306eec..cba710f 100644
--- a/libs/hwui/renderthread/CanvasContext.h
+++ b/libs/hwui/renderthread/CanvasContext.h
@@ -30,6 +30,7 @@
#include "renderthread/RenderTask.h"
#include "renderthread/RenderThread.h"
#include "utils/RingBuffer.h"
+#include "ColorMode.h"
#include <SkBitmap.h>
#include <SkRect.h>
@@ -119,7 +120,7 @@
void setLightAlpha(uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha);
void setLightGeometry(const Vector3& lightCenter, float lightRadius);
void setOpaque(bool opaque);
- void setWideGamut(bool wideGamut);
+ void setColorMode(ColorMode mode);
bool makeCurrent();
void prepareTree(TreeInfo& info, int64_t* uiFrameInfo, int64_t syncQueued, RenderNode* target);
void draw();
@@ -211,6 +212,7 @@
bool isSwapChainStuffed();
bool surfaceRequiresRedraw();
void setPresentTime();
+ void setupPipelineSurface();
SkRect computeDirtyRect(const Frame& frame, SkRect* dirty);
diff --git a/libs/hwui/renderthread/EglManager.cpp b/libs/hwui/renderthread/EglManager.cpp
index c701353..2a8aa8c 100644
--- a/libs/hwui/renderthread/EglManager.cpp
+++ b/libs/hwui/renderthread/EglManager.cpp
@@ -76,6 +76,7 @@
bool glColorSpace = false;
bool scRGB = false;
bool displayP3 = false;
+ bool hdr = false;
bool contextPriority = false;
bool surfacelessContext = false;
bool nativeFenceSync = false;
@@ -86,7 +87,8 @@
EglManager::EglManager()
: mEglDisplay(EGL_NO_DISPLAY)
, mEglConfig(nullptr)
- , mEglConfigWideGamut(nullptr)
+ , mEglConfigF16(nullptr)
+ , mEglConfig1010102(nullptr)
, mEglContext(EGL_NO_CONTEXT)
, mPBufferSurface(EGL_NO_SURFACE)
, mCurrentSurface(EGL_NO_SURFACE)
@@ -143,8 +145,7 @@
} else {
LOG_ALWAYS_FATAL("Unsupported wide color space.");
}
- mHasWideColorGamutSupport = EglExtensions.glColorSpace && hasWideColorSpaceExtension &&
- mEglConfigWideGamut != EGL_NO_CONFIG_KHR;
+ mHasWideColorGamutSupport = EglExtensions.glColorSpace && hasWideColorSpaceExtension;
}
EGLConfig EglManager::load8BitsConfig(EGLDisplay display, EglManager::SwapBehavior swapBehavior) {
@@ -177,6 +178,35 @@
return config;
}
+EGLConfig EglManager::load1010102Config(EGLDisplay display, SwapBehavior swapBehavior) {
+ EGLint eglSwapBehavior =
+ (swapBehavior == SwapBehavior::Preserved) ? EGL_SWAP_BEHAVIOR_PRESERVED_BIT : 0;
+ // If we reached this point, we have a valid swap behavior
+ EGLint attribs[] = {EGL_RENDERABLE_TYPE,
+ EGL_OPENGL_ES2_BIT,
+ EGL_RED_SIZE,
+ 10,
+ EGL_GREEN_SIZE,
+ 10,
+ EGL_BLUE_SIZE,
+ 10,
+ EGL_ALPHA_SIZE,
+ 2,
+ EGL_DEPTH_SIZE,
+ 0,
+ EGL_STENCIL_SIZE,
+ STENCIL_BUFFER_SIZE,
+ EGL_SURFACE_TYPE,
+ EGL_WINDOW_BIT | eglSwapBehavior,
+ EGL_NONE};
+ EGLConfig config = EGL_NO_CONFIG_KHR;
+ EGLint numConfigs = 1;
+ if (!eglChooseConfig(display, attribs, &config, numConfigs, &numConfigs) || numConfigs != 1) {
+ return EGL_NO_CONFIG_KHR;
+ }
+ return config;
+}
+
EGLConfig EglManager::loadFP16Config(EGLDisplay display, SwapBehavior swapBehavior) {
EGLint eglSwapBehavior =
(swapBehavior == SwapBehavior::Preserved) ? EGL_SWAP_BEHAVIOR_PRESERVED_BIT : 0;
@@ -230,6 +260,7 @@
EglExtensions.pixelFormatFloat = extensions.has("EGL_EXT_pixel_format_float");
EglExtensions.scRGB = extensions.has("EGL_EXT_gl_colorspace_scrgb");
EglExtensions.displayP3 = extensions.has("EGL_EXT_gl_colorspace_display_p3_passthrough");
+ EglExtensions.hdr = extensions.has("EGL_EXT_gl_colorspace_bt2020_pq");
EglExtensions.contextPriority = extensions.has("EGL_IMG_context_priority");
EglExtensions.surfacelessContext = extensions.has("EGL_KHR_surfaceless_context");
EglExtensions.fenceSync = extensions.has("EGL_KHR_fence_sync");
@@ -260,18 +291,20 @@
LOG_ALWAYS_FATAL("Failed to choose config, error = %s", eglErrorString());
}
}
- SkColorType wideColorType = DeviceInfo::get()->getWideColorType();
// When we reach this point, we have a valid swap behavior
- if (wideColorType == SkColorType::kRGBA_F16_SkColorType && EglExtensions.pixelFormatFloat) {
- mEglConfigWideGamut = loadFP16Config(mEglDisplay, mSwapBehavior);
- if (mEglConfigWideGamut == EGL_NO_CONFIG_KHR) {
+ if (EglExtensions.pixelFormatFloat) {
+ mEglConfigF16 = loadFP16Config(mEglDisplay, mSwapBehavior);
+ if (mEglConfigF16 == EGL_NO_CONFIG_KHR) {
ALOGE("Device claims wide gamut support, cannot find matching config, error = %s",
eglErrorString());
EglExtensions.pixelFormatFloat = false;
}
- } else if (wideColorType == SkColorType::kN32_SkColorType) {
- mEglConfigWideGamut = load8BitsConfig(mEglDisplay, mSwapBehavior);
+ }
+ mEglConfig1010102 = load1010102Config(mEglDisplay, mSwapBehavior);
+ if (mEglConfig1010102 == EGL_NO_CONFIG_KHR) {
+ ALOGW("Failed to initialize 101010-2 format, error = %s",
+ eglErrorString());
}
}
@@ -311,8 +344,9 @@
sk_sp<SkColorSpace> colorSpace) {
LOG_ALWAYS_FATAL_IF(!hasEglContext(), "Not initialized");
- bool wideColorGamut = colorMode == ColorMode::WideColorGamut && mHasWideColorGamutSupport &&
- EglExtensions.noConfigContext;
+ if (!mHasWideColorGamutSupport || !EglExtensions.noConfigContext) {
+ colorMode = ColorMode::Default;
+ }
// The color space we want to use depends on whether linear blending is turned
// on and whether the app has requested wide color gamut rendering. When wide
@@ -338,26 +372,47 @@
// list is considered empty if the first entry is EGL_NONE
EGLint attribs[] = {EGL_NONE, EGL_NONE, EGL_NONE};
+ EGLConfig config = mEglConfig;
+ if (DeviceInfo::get()->getWideColorType() == kRGBA_F16_SkColorType) {
+ if (mEglConfigF16 == EGL_NO_CONFIG_KHR) {
+ colorMode = ColorMode::Default;
+ } else {
+ config = mEglConfigF16;
+ }
+ }
if (EglExtensions.glColorSpace) {
attribs[0] = EGL_GL_COLORSPACE_KHR;
- if (wideColorGamut) {
- skcms_Matrix3x3 colorGamut;
- LOG_ALWAYS_FATAL_IF(!colorSpace->toXYZD50(&colorGamut),
- "Could not get gamut matrix from color space");
- if (memcmp(&colorGamut, &SkNamedGamut::kDisplayP3, sizeof(colorGamut)) == 0) {
- attribs[1] = EGL_GL_COLORSPACE_DISPLAY_P3_PASSTHROUGH_EXT;
- } else if (memcmp(&colorGamut, &SkNamedGamut::kSRGB, sizeof(colorGamut)) == 0) {
- attribs[1] = EGL_GL_COLORSPACE_SCRGB_EXT;
- } else {
- LOG_ALWAYS_FATAL("Unreachable: unsupported wide color space.");
+ switch (colorMode) {
+ case ColorMode::Default:
+ attribs[1] = EGL_GL_COLORSPACE_LINEAR_KHR;
+ break;
+ case ColorMode::WideColorGamut: {
+ skcms_Matrix3x3 colorGamut;
+ LOG_ALWAYS_FATAL_IF(!colorSpace->toXYZD50(&colorGamut),
+ "Could not get gamut matrix from color space");
+ if (memcmp(&colorGamut, &SkNamedGamut::kDisplayP3, sizeof(colorGamut)) == 0) {
+ attribs[1] = EGL_GL_COLORSPACE_DISPLAY_P3_PASSTHROUGH_EXT;
+ } else if (memcmp(&colorGamut, &SkNamedGamut::kSRGB, sizeof(colorGamut)) == 0) {
+ attribs[1] = EGL_GL_COLORSPACE_SCRGB_EXT;
+ } else if (memcmp(&colorGamut, &SkNamedGamut::kRec2020, sizeof(colorGamut)) == 0) {
+ attribs[1] = EGL_GL_COLORSPACE_BT2020_PQ_EXT;
+ } else {
+ LOG_ALWAYS_FATAL("Unreachable: unsupported wide color space.");
+ }
+ break;
}
- } else {
- attribs[1] = EGL_GL_COLORSPACE_LINEAR_KHR;
+ case ColorMode::Hdr:
+ config = mEglConfigF16;
+ attribs[1] = EGL_GL_COLORSPACE_BT2020_PQ_EXT;
+ break;
+ case ColorMode::Hdr10:
+ config = mEglConfig1010102;
+ attribs[1] = EGL_GL_COLORSPACE_BT2020_PQ_EXT;
+ break;
}
}
- EGLSurface surface = eglCreateWindowSurface(
- mEglDisplay, wideColorGamut ? mEglConfigWideGamut : mEglConfig, window, attribs);
+ EGLSurface surface = eglCreateWindowSurface(mEglDisplay, config, window, attribs);
if (surface == EGL_NO_SURFACE) {
return Error<EGLint>{eglGetError()};
}
diff --git a/libs/hwui/renderthread/EglManager.h b/libs/hwui/renderthread/EglManager.h
index f67fb31..69f3ed0 100644
--- a/libs/hwui/renderthread/EglManager.h
+++ b/libs/hwui/renderthread/EglManager.h
@@ -88,6 +88,7 @@
static EGLConfig load8BitsConfig(EGLDisplay display, SwapBehavior swapBehavior);
static EGLConfig loadFP16Config(EGLDisplay display, SwapBehavior swapBehavior);
+ static EGLConfig load1010102Config(EGLDisplay display, SwapBehavior swapBehavior);
void initExtensions();
void createPBufferSurface();
@@ -97,7 +98,8 @@
EGLDisplay mEglDisplay;
EGLConfig mEglConfig;
- EGLConfig mEglConfigWideGamut;
+ EGLConfig mEglConfigF16;
+ EGLConfig mEglConfig1010102;
EGLContext mEglContext;
EGLSurface mPBufferSurface;
EGLSurface mCurrentSurface;
diff --git a/libs/hwui/renderthread/IRenderPipeline.h b/libs/hwui/renderthread/IRenderPipeline.h
index c3c2286..a04738d 100644
--- a/libs/hwui/renderthread/IRenderPipeline.h
+++ b/libs/hwui/renderthread/IRenderPipeline.h
@@ -22,6 +22,7 @@
#include "Lighting.h"
#include "SwapBehavior.h"
#include "hwui/Bitmap.h"
+#include "ColorMode.h"
#include <SkRect.h>
#include <utils/RefBase.h>
@@ -42,16 +43,6 @@
enum class MakeCurrentResult { AlreadyCurrent, Failed, Succeeded };
-enum class ColorMode {
- // SRGB means HWUI will produce buffer in SRGB color space.
- SRGB,
- // WideColorGamut means HWUI would support rendering scRGB non-linear into
- // a signed buffer with enough range to support the wide color gamut of the
- // display.
- WideColorGamut,
- // Hdr
-};
-
class Frame;
class IRenderPipeline {
diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index b764f74b..aad0cca 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -109,8 +109,8 @@
mRenderThread.queue().post([=]() { mContext->setOpaque(opaque); });
}
-void RenderProxy::setWideGamut(bool wideGamut) {
- mRenderThread.queue().post([=]() { mContext->setWideGamut(wideGamut); });
+void RenderProxy::setColorMode(ColorMode mode) {
+ mRenderThread.queue().post([=]() { mContext->setColorMode(mode); });
}
int64_t* RenderProxy::frameInfo() {
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index 16eabad..33dabc9 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -24,6 +24,7 @@
#include "../FrameMetricsObserver.h"
#include "../IContextFactory.h"
+#include "ColorMode.h"
#include "DrawFrameTask.h"
#include "SwapBehavior.h"
#include "hwui/Bitmap.h"
@@ -77,7 +78,7 @@
void setLightAlpha(uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha);
void setLightGeometry(const Vector3& lightCenter, float lightRadius);
void setOpaque(bool opaque);
- void setWideGamut(bool wideGamut);
+ void setColorMode(ColorMode mode);
int64_t* frameInfo();
int syncAndDrawFrame();
void destroy();
diff --git a/libs/hwui/utils/Color.cpp b/libs/hwui/utils/Color.cpp
index ca1bf69..eff34a8 100644
--- a/libs/hwui/utils/Color.cpp
+++ b/libs/hwui/utils/Color.cpp
@@ -344,5 +344,27 @@
static_cast<uint8_t>(rgb.b * 255));
}
+// Note that SkColorSpace doesn't have the notion of an unspecified SDR white
+// level.
+static constexpr float kDefaultSDRWhiteLevel = 150.f;
+
+skcms_TransferFunction GetPQSkTransferFunction(float sdr_white_level) {
+ if (sdr_white_level <= 0.f) {
+ sdr_white_level = kDefaultSDRWhiteLevel;
+ }
+ // The generic PQ transfer function produces normalized luminance values i.e.
+ // the range 0-1 represents 0-10000 nits for the reference display, but we
+ // want to map 1.0 to |sdr_white_level| nits so we need to scale accordingly.
+ const double w = 10000. / sdr_white_level;
+ // Distribute scaling factor W by scaling A and B with X ^ (1/F):
+ // ((A + Bx^C) / (D + Ex^C))^F * W = ((A + Bx^C) / (D + Ex^C) * W^(1/F))^F
+ // See https://crbug.com/1058580#c32 for discussion.
+ skcms_TransferFunction fn = SkNamedTransferFn::kPQ;
+ const double ws = pow(w, 1. / fn.f);
+ fn.a = ws * fn.a;
+ fn.b = ws * fn.b;
+ return fn;
+}
+
} // namespace uirenderer
} // namespace android
diff --git a/libs/hwui/utils/Color.h b/libs/hwui/utils/Color.h
index 71ed683..1654072 100644
--- a/libs/hwui/utils/Color.h
+++ b/libs/hwui/utils/Color.h
@@ -126,6 +126,7 @@
Lab sRGBToLab(SkColor color);
SkColor LabToSRGB(const Lab& lab, SkAlpha alpha);
+skcms_TransferFunction GetPQSkTransferFunction(float sdr_white_level = 0.f);
} /* namespace uirenderer */
} /* namespace android */