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1.前言
2.HWComposer、ComposerImpl、Composer、Hwc2::Composer定义与实现
1.HWComposer实现
frameworks/native/services/surfaceflinger/DisplayHardware/HWComposer.h
<1>.android::HWComposer定义
namespace Hwc2 {
class Composer;
}
namespace android {
class HWComposer {
virtual ~HWComposer();
virtual void setCallback(HWC2::ComposerCallback*) = 0;
....
};
}
<2>.impl::HWComposer定义(继承自android::HWComposer)
namespace impl {
class HWComposer final : public android::HWComposer {
public:
explicit HWComposer(std::unique_ptr<Hwc2::Composer> composer);
explicit HWComposer(const std::string& composerServiceName);
~HWComposer() override;
};
}
<3>.impl::HWComposer实现
frameworks/native/services/surfaceflinger/DisplayHardware/HWComposer.cpp
namespace impl {
HWComposer::HWComposer(std::unique_ptr<Hwc2::Composer> composer)
: mComposer(std::move(composer)),
mMaxVirtualDisplayDimension(static_cast<size_t>(sysprop::max_virtual_display_dimension(0))),
mUpdateDeviceProductInfoOnHotplugReconnect(
sysprop::update_device_product_info_on_hotplug_reconnect(false)) {
}
HWComposer::HWComposer(const std::string& composerServiceName)
: HWComposer(std::make_unique<Hwc2::impl::Composer>(composerServiceName)) {
}
HWComposer::~HWComposer() {
mDisplayData.clear();
}
}
2.ComposerImpl实现（Hwc2::Composer是它的别名）
hardware/interfaces/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/Composer.h
<1>.Composer定义，它是ComposerImpl的别名
using Composer = detail::ComposerImpl<IComposer, ComposerHal>;
template <typename Interface, typename Hal>
class ComposerImpl : public Interface {
public:
static std::unique_ptr<ComposerImpl> create(std::unique_ptr<Hal> hal) {
