1 files changed, 66 insertions, 0 deletions
diff --git a/src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/ControllerMappingHelper.java b/src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/ControllerMappingHelper.java
new file mode 100644
index 000000000..92fa50edf
--- /dev/null
+++ b/src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/ControllerMappingHelper.java
@@ -0,0 +1,66 @@
+package org.yuzu.yuzu_emu.utils;
+
+import android.view.InputDevice;
+import android.view.KeyEvent;
+import android.view.MotionEvent;
+
+/**
+ * Some controllers have incorrect mappings. This class has special-case fixes for them.
+ */
+public class ControllerMappingHelper {
+    /**
+     * Some controllers report extra button presses that can be ignored.
+     */
+    public boolean shouldKeyBeIgnored(InputDevice inputDevice, int keyCode) {
+        if (isDualShock4(inputDevice)) {
+            // The two analog triggers generate analog motion events as well as a keycode.
+            // We always prefer to use the analog values, so throw away the button press
+            return keyCode == KeyEvent.KEYCODE_BUTTON_L2 || keyCode == KeyEvent.KEYCODE_BUTTON_R2;
+        }
+        return false;
+    }
+
+    /**
+     * Scale an axis to be zero-centered with a proper range.
+     */
+    public float scaleAxis(InputDevice inputDevice, int axis, float value) {
+        if (isDualShock4(inputDevice)) {
+            // Android doesn't have correct mappings for this controller's triggers. It reports them
+            // as RX & RY, centered at -1.0, and with a range of [-1.0, 1.0]
+            // Scale them to properly zero-centered with a range of [0.0, 1.0].
+            if (axis == MotionEvent.AXIS_RX || axis == MotionEvent.AXIS_RY) {
+                return (value + 1) / 2.0f;
+            }
+        } else if (isXboxOneWireless(inputDevice)) {
+            // Same as the DualShock 4, the mappings are missing.
+            if (axis == MotionEvent.AXIS_Z || axis == MotionEvent.AXIS_RZ) {
+                return (value + 1) / 2.0f;
+            }
+            if (axis == MotionEvent.AXIS_GENERIC_1) {
+                // This axis is stuck at ~.5. Ignore it.
+                return 0.0f;
+            }
+        } else if (isMogaPro2Hid(inputDevice)) {
+            // This controller has a broken axis that reports a constant value. Ignore it.
+            if (axis == MotionEvent.AXIS_GENERIC_1) {
+                return 0.0f;
+            }
+        }
+        return value;
+    }
+
+    private boolean isDualShock4(InputDevice inputDevice) {
+        // Sony DualShock 4 controller
+        return inputDevice.getVendorId() == 0x54c && inputDevice.getProductId() == 0x9cc;
+    }
+
+    private boolean isXboxOneWireless(InputDevice inputDevice) {
+        // Microsoft Xbox One controller
+        return inputDevice.getVendorId() == 0x45e && inputDevice.getProductId() == 0x2e0;
+    }
+
+    private boolean isMogaPro2Hid(InputDevice inputDevice) {
+        // Moga Pro 2 HID
+        return inputDevice.getVendorId() == 0x20d6 && inputDevice.getProductId() == 0x6271;
+    }
+}