InputCommon: Simplified StickGate interface and moved class into its own file. Changed default input radius to perform no resizing. Tweaked the indicator colors a bit to improve visibility. Cleaned up some math and code.

4 files changed, 111 insertions, 96 deletions

diff --git a/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.cpp b/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.cpp
index 5368c6b7ba..3f766d5e45 100644
--- a/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.cpp
+++ b/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.cpp
@@ -4,9 +4,7 @@
 
 #include "InputCommon/ControllerEmu/ControlGroup/AnalogStick.h"
 
-#include <algorithm>
 #include <cmath>
-#include <memory>
 
 #include "Common/Common.h"
 #include "Common/MathUtil.h"
@@ -33,8 +31,10 @@ AnalogStick::AnalogStick(const char* const name_, const char* const ui_name_,
 
   controls.emplace_back(std::make_unique<Input>(Translate, _trans("Modifier")));
 
+  // Set default input radius to that of the gate radius (no resizing)
   numeric_settings.emplace_back(
-      std::make_unique<NumericSetting>(_trans("Input Radius"), 1.0, 0, 100));
+      std::make_unique<NumericSetting>(_trans("Input Radius"), GetGateRadiusAtAngle(0.0), 0, 100));
+  // Set default input shape to an octagon (no reshaping)
   numeric_settings.emplace_back(
       std::make_unique<NumericSetting>(_trans("Input Shape"), 0.0, 0, 50));
   numeric_settings.emplace_back(std::make_unique<NumericSetting>(_trans("Dead Zone"), 0, 0, 50));
@@ -50,9 +50,7 @@ AnalogStick::StateData AnalogStick::GetState(bool adjusted)
     return {x, y};
 
   // TODO: make the AtAngle functions work with negative angles:
-  const ControlState ang = atan2(y, x) + MathUtil::TAU;
-  const ControlState ang_sin = sin(ang);
-  const ControlState ang_cos = cos(ang);
+  const ControlState ang = std::atan2(y, x) + MathUtil::TAU;
 
   const ControlState gate_max_dist = GetGateRadiusAtAngle(ang);
   const ControlState input_max_dist = GetInputRadiusAtAngle(ang);
@@ -82,9 +80,8 @@ AnalogStick::StateData AnalogStick::GetState(bool adjusted)
   // Scale to the gate shape/radius:
   dist = dist *= gate_max_dist;
 
-  y = std::max(-1.0, std::min(1.0, ang_sin * dist));
-  x = std::max(-1.0, std::min(1.0, ang_cos * dist));
-
+  x = MathUtil::Clamp(std::cos(ang) * dist, -1.0, 1.0);
+  y = MathUtil::Clamp(std::sin(ang) * dist, -1.0, 1.0);
   return {x, y};
 }
 
@@ -111,57 +108,16 @@ ControlState AnalogStick::CalculateInputShapeRadiusAtAngle(double ang) const
   {
     // Between 0 and 25 return a shape between octagon and circle
     const auto amt = shape;
-    return OctagonStickGate::ComputeRadiusAtAngle(ang) * (1 - amt) + amt;
+    return OctagonStickGate(1).GetRadiusAtAngle(ang) * (1 - amt) + amt;
   }
   else
   {
     // Between 25 and 50 return a shape between circle and square
     const auto amt = shape - 1.0;
-    return (1 - amt) + SquareStickGate::ComputeRadiusAtAngle(ang) * amt;
+    return (1 - amt) + SquareStickGate(1).GetRadiusAtAngle(ang) * amt;
   }
 }
 
-OctagonStickGate::OctagonStickGate(ControlState radius) : m_radius(radius)
-{
-}
-
-ControlState OctagonStickGate::GetRadiusAtAngle(double ang) const
-{
-  return ComputeRadiusAtAngle(ang) * m_radius;
-}
-
-ControlState OctagonStickGate::ComputeRadiusAtAngle(double ang)
-{
-  // Ratio of octagon circumcircle to incircle:
-  const double incircle_radius = 0.923879532511287;
-  const double section_ang = MathUtil::TAU / 8;
-  return incircle_radius / std::cos(std::fmod(ang, section_ang) - section_ang / 2);
-}
-
-RoundStickGate::RoundStickGate(ControlState radius) : m_radius(radius)
-{
-}
-
-ControlState RoundStickGate::GetRadiusAtAngle(double) const
-{
-  return m_radius;
-}
-
-SquareStickGate::SquareStickGate(ControlState half_width) : m_half_width(half_width)
-{
-}
-
-ControlState SquareStickGate::GetRadiusAtAngle(double ang) const
-{
-  return ComputeRadiusAtAngle(ang) * m_half_width;
-}
-
-ControlState SquareStickGate::ComputeRadiusAtAngle(double ang)
-{
-  const double section_ang = MathUtil::TAU / 4;
-  return 1 / std::cos(std::fmod(ang + section_ang / 2, section_ang) - section_ang / 2);
-}
-
 OctagonAnalogStick::OctagonAnalogStick(const char* name, ControlState gate_radius)
     : OctagonAnalogStick(name, name, gate_radius)
 {
diff --git a/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.h b/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.h
index 336669124a..2351189f74 100644
--- a/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.h
+++ b/Source/Core/InputCommon/ControllerEmu/ControlGroup/AnalogStick.h
@@ -5,54 +5,11 @@
 #pragma once
 
 #include "InputCommon/ControllerEmu/ControlGroup/ControlGroup.h"
+#include "InputCommon/ControllerEmu/StickGate.h"
 #include "InputCommon/ControllerInterface/Device.h"
 
 namespace ControllerEmu
 {
-// An abstract class representing the plastic shell that limits an analog stick's movement.
-class StickGate
-{
-public:
-  // Angle is in radians and should be non-negative
-  virtual ControlState GetRadiusAtAngle(double ang) const = 0;
-};
-
-// An octagon-shaped stick gate is found on most Nintendo GC/Wii analog sticks.
-class OctagonStickGate : public StickGate
-{
-public:
-  explicit OctagonStickGate(ControlState radius);
-  ControlState GetRadiusAtAngle(double ang) const override;
-
-  static ControlState ComputeRadiusAtAngle(double ang);
-
-  const ControlState m_radius;
-};
-
-// A round-shaped stick gate. Possibly found on 3rd-party accessories.
-class RoundStickGate : public StickGate
-{
-public:
-  explicit RoundStickGate(ControlState radius);
-  ControlState GetRadiusAtAngle(double ang) const override;
-
-private:
-  const ControlState m_radius;
-};
-
-// A square-shaped stick gate. e.g. keyboard input.
-class SquareStickGate : public StickGate
-{
-public:
-  explicit SquareStickGate(ControlState half_width);
-  ControlState GetRadiusAtAngle(double ang) const override;
-
-  static ControlState ComputeRadiusAtAngle(double ang);
-
-private:
-  const ControlState m_half_width;
-};
-
 class AnalogStick : public ControlGroup
 {
 public:
diff --git a/Source/Core/InputCommon/ControllerEmu/StickGate.cpp b/Source/Core/InputCommon/ControllerEmu/StickGate.cpp
new file mode 100644
index 0000000000..c0c2a668a3
--- /dev/null
+++ b/Source/Core/InputCommon/ControllerEmu/StickGate.cpp
@@ -0,0 +1,47 @@
+// Copyright 2018 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include "InputCommon/ControllerEmu/StickGate.h"
+
+#include <cmath>
+
+#include "Common/MathUtil.h"
+
+namespace ControllerEmu
+{
+OctagonStickGate::OctagonStickGate(ControlState radius) : m_radius(radius)
+{
+}
+
+ControlState OctagonStickGate::GetRadiusAtAngle(double ang) const
+{
+  constexpr int sides = 8;
+  constexpr double sum_int_angles = (sides - 2) * MathUtil::PI;
+  constexpr double half_int_angle = sum_int_angles / sides / 2;
+
+  ang = std::fmod(ang, MathUtil::TAU / sides);
+  // Solve ASA triangle using The Law of Sines:
+  return m_radius / std::sin(MathUtil::PI - ang - half_int_angle) * std::sin(half_int_angle);
+}
+
+RoundStickGate::RoundStickGate(ControlState radius) : m_radius(radius)
+{
+}
+
+ControlState RoundStickGate::GetRadiusAtAngle(double) const
+{
+  return m_radius;
+}
+
+SquareStickGate::SquareStickGate(ControlState half_width) : m_half_width(half_width)
+{
+}
+
+ControlState SquareStickGate::GetRadiusAtAngle(double ang) const
+{
+  constexpr double section_ang = MathUtil::TAU / 4;
+  return m_half_width / std::cos(std::fmod(ang + section_ang / 2, section_ang) - section_ang / 2);
+}
+
+}  // namespace ControllerEmu
diff --git a/Source/Core/InputCommon/ControllerEmu/StickGate.h b/Source/Core/InputCommon/ControllerEmu/StickGate.h
new file mode 100644
index 0000000000..decb15d234
--- /dev/null
+++ b/Source/Core/InputCommon/ControllerEmu/StickGate.h
@@ -0,0 +1,55 @@
+// Copyright 2018 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "InputCommon/ControlReference/ControlReference.h"
+
+namespace ControllerEmu
+{
+// An abstract class representing the plastic shell that limits an analog stick's movement.
+class StickGate
+{
+public:
+  // Angle is in radians and should be non-negative
+  virtual ControlState GetRadiusAtAngle(double ang) const = 0;
+
+  virtual ~StickGate() = default;
+};
+
+// An octagon-shaped stick gate is found on most Nintendo GC/Wii analog sticks.
+class OctagonStickGate : public StickGate
+{
+public:
+  // Radius of circumscribed circle
+  explicit OctagonStickGate(ControlState radius);
+  ControlState GetRadiusAtAngle(double ang) const override final;
+
+private:
+  const ControlState m_radius;
+};
+
+// A round-shaped stick gate. Possibly found on 3rd-party accessories.
+class RoundStickGate : public StickGate
+{
+public:
+  explicit RoundStickGate(ControlState radius);
+  ControlState GetRadiusAtAngle(double ang) const override final;
+
+private:
+  const ControlState m_radius;
+};
+
+// A square-shaped stick gate. e.g. keyboard input.
+class SquareStickGate : public StickGate
+{
+public:
+  explicit SquareStickGate(ControlState half_width);
+  ControlState GetRadiusAtAngle(double ang) const override final;
+
+private:
+  const ControlState m_half_width;
+};
+
+}  // namespace ControllerEmu