input_common: Add VibrationDevice and VibrationDeviceFactory

A vibration device is an input device that returns an unsigned byte as status.
It represents whether the vibration device supports vibration or not.
If the status returns 1, it supports vibration. Otherwise, it does not support vibration.

src/input_common/gcadapter/gc_adapter.cpp

@@ -230,10 +230,8 @@ void Adapter::SendVibrations() {
     vibration_changed = false;
 }
 
-bool Adapter::RumblePlay(std::size_t port, f32 amplitude) {
-    amplitude = std::clamp(amplitude, 0.0f, 1.0f);
-    const auto raw_amp = static_cast<u8>(amplitude * 0x8);
-    pads[port].rumble_amplitude = raw_amp;
+bool Adapter::RumblePlay(std::size_t port, u8 amplitude) {
+    pads[port].rumble_amplitude = amplitude;
 
     return rumble_enabled;
 }

src/input_common/gcadapter/gc_adapter.h

@@ -77,8 +77,8 @@ public:
     Adapter();
     ~Adapter();
 
-    /// Request a vibration for a controlelr
-    bool RumblePlay(std::size_t port, f32 amplitude);
+    /// Request a vibration for a controller
+    bool RumblePlay(std::size_t port, u8 amplitude);
 
     /// Used for polling
     void BeginConfiguration();

src/input_common/gcadapter/gc_poller.cpp

@@ -15,7 +15,7 @@ namespace InputCommon {
 
 class GCButton final : public Input::ButtonDevice {
 public:
-    explicit GCButton(u32 port_, s32 button_, GCAdapter::Adapter* adapter)
+    explicit GCButton(u32 port_, s32 button_, const GCAdapter::Adapter* adapter)
         : port(port_), button(button_), gcadapter(adapter) {}
 
     ~GCButton() override;
@@ -27,18 +27,10 @@ public:
         return false;
     }
 
-    bool SetRumblePlay(f32 amp_high, f32 amp_low, f32 freq_high, f32 freq_low) const override {
-        const float amplitude = amp_high + amp_low > 2.0f ? 1.0f : (amp_high + amp_low) * 0.5f;
-        const auto new_amp =
-            static_cast<f32>(pow(amplitude, 0.5f) * (3.0f - 2.0f * pow(amplitude, 0.15f)));
-
-        return gcadapter->RumblePlay(port, new_amp);
-    }
-
 private:
     const u32 port;
     const s32 button;
-    GCAdapter::Adapter* gcadapter;
+    const GCAdapter::Adapter* gcadapter;
 };
 
 class GCAxisButton final : public Input::ButtonDevice {
@@ -299,4 +291,42 @@ Common::ParamPackage GCAnalogFactory::GetNextInput() {
     return params;
 }
 
+class GCVibration final : public Input::VibrationDevice {
+public:
+    explicit GCVibration(u32 port_, GCAdapter::Adapter* adapter)
+        : port(port_), gcadapter(adapter) {}
+
+    u8 GetStatus() const override {
+        return gcadapter->RumblePlay(port, 0);
+    }
+
+    bool SetRumblePlay(f32 amp_low, f32 freq_low, f32 amp_high, f32 freq_high) const override {
+        const auto mean_amplitude = (amp_low + amp_high) * 0.5f;
+        const auto processed_amplitude = static_cast<u8>(
+            pow(mean_amplitude, 0.5f) * (3.0f - 2.0f * pow(mean_amplitude, 0.15f)) * 0x8);
+
+        return gcadapter->RumblePlay(port, processed_amplitude);
+    }
+
+private:
+    const u32 port;
+    GCAdapter::Adapter* gcadapter;
+};
+
+/// An vibration device factory that creates vibration devices from GC Adapter
+GCVibrationFactory::GCVibrationFactory(std::shared_ptr<GCAdapter::Adapter> adapter_)
+    : adapter(std::move(adapter_)) {}
+
+/**
+ * Creates a vibration device from a joystick
+ * @param params contains parameters for creating the device:
+ *     - "port": the nth gcpad on the adapter
+ */
+std::unique_ptr<Input::VibrationDevice> GCVibrationFactory::Create(
+    const Common::ParamPackage& params) {
+    const auto port = static_cast<u32>(params.Get("port", 0));
+
+    return std::make_unique<GCVibration>(port, adapter.get());
+}
+
 } // namespace InputCommon

src/input_common/gcadapter/gc_poller.h

@@ -64,4 +64,15 @@ private:
     bool polling = false;
 };
 
+/// A vibration device factory creates vibration devices from GC Adapter
+class GCVibrationFactory final : public Input::Factory<Input::VibrationDevice> {
+public:
+    explicit GCVibrationFactory(std::shared_ptr<GCAdapter::Adapter> adapter_);
+
+    std::unique_ptr<Input::VibrationDevice> Create(const Common::ParamPackage& params) override;
+
+private:
+    std::shared_ptr<GCAdapter::Adapter> adapter;
+};
+
 } // namespace InputCommon