Gamepad API support for chrome on android

content/public/android/java/src/org/chromium/content/browser/GamepadMappings.java

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.content.browser;
+
+import android.view.KeyEvent;
+
+import org.chromium.content.browser.input.CanonicalAxisIndex;
+import org.chromium.content.browser.input.CanonicalButtonIndex;
+
+/*
+* Class to manage mapping information related to each supported gamepad controller device.
+*/
+class GamepadMappings {
+    public static boolean mapToStandardGamepad(float[] mappedAxis, float[] mappedButtons,
+                                               float[] rawAxes, float[] rawButtons,

[Ted C, 2014/04/04 18:52:18]

use java indenting

[SaurabhK, 2014/04/11 14:41:42]

On 2014/04/04 18:52:18, Ted C wrote:

Done.

+                                               String deviceName) {
+        boolean isMapped = true;
+        if (deviceName.contains("NVIDIA Corporation NVIDIA Controller")) {
+            mapShieldGamepad(mappedButtons, rawButtons, mappedAxis, rawAxes);
+        }
+        else if (deviceName.contains("Microsoft X-Box 360 pad")) {
+            mapXBox360Gamepad(mappedButtons, rawButtons, mappedAxis, rawAxes);
+        }
+        else {

[Ted C, 2014/04/04 18:52:18]

needs to go on the line above with the }

[SaurabhK, 2014/04/11 14:41:42]

On 2014/04/04 18:52:18, Ted C wrote:

Removed else after review comments from Jdduke

+            mapUnkownGamepad(mappedButtons, rawButtons, mappedAxis, rawAxes);
+            isMapped = false;
+        }
+        return isMapped;
+    }
+
+    private static void mapCommonButtons(float[] mappedButtons, float[] rawButtons) {
+        mappedButtons[CanonicalButtonIndex.BUTTON_PRIMARY] = rawButtons[KeyEvent.KEYCODE_BUTTON_A];
+        mappedButtons[CanonicalButtonIndex.BUTTON_SECONDARY] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_B];

[Ted C, 2014/04/04 18:52:18]

should be indented 8 from the start of the previous line (same in the rest of
the file)

[SaurabhK, 2014/04/11 14:41:42]

On 2014/04/04 18:52:18, Ted C wrote:

Done.

+        mappedButtons[CanonicalButtonIndex.BUTTON_TERTIARY] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_X];
+        mappedButtons[CanonicalButtonIndex.BUTTON_QUATERNARY] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_Y];
+        mappedButtons[CanonicalButtonIndex.BUTTON_LEFT_SHOULDER] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_L1];
+        mappedButtons[CanonicalButtonIndex.BUTTON_RIGHT_SHOULDER] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_R1];
+        mappedButtons[CanonicalButtonIndex.BUTTON_BACK_SELECT] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_SELECT];
+        mappedButtons[CanonicalButtonIndex.BUTTON_START] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_START];
+        mappedButtons[CanonicalButtonIndex.BUTTON_LEFT_THUMBSTICK] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_THUMBL];
+        mappedButtons[CanonicalButtonIndex.BUTTON_RIGHT_THUMBSTICK] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_THUMBR];
+        mappedButtons[CanonicalButtonIndex.BUTTON_META] = rawButtons[KeyEvent.KEYCODE_BUTTON_MODE];
+    }
+
+    private static void mapDpadButtonsToAxes(float[] mappedButtons, float[] rawAxes) {
+        // Negative value indicates dpad up.
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_UP] = negativeAxisValueAsButton(rawAxes[9]);
+        // Positive axis value indicates dpad down.
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_DOWN] =
+                            positiveAxisValueAsButton(rawAxes[9]);
+        // Positive axis value indicates dpad right.
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_RIGHT] =
+                            positiveAxisValueAsButton(rawAxes[8]);
+        // Negative value indicates dpad left.
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_LEFT] =
+                            negativeAxisValueAsButton(rawAxes[8]);
+    }
+
+    private static void mapAxes(float[] mappedAxis, float[] rawAxes) {
+        // Standard gamepad can have only four axes.
+        mappedAxis[CanonicalAxisIndex.AXIS_LEFT_STICK_X] = rawAxes[0];
+        mappedAxis[CanonicalAxisIndex.AXIS_LEFT_STICK_Y] = rawAxes[1];
+        mappedAxis[CanonicalAxisIndex.AXIS_RIGHT_STICK_X] = rawAxes[4];
+        mappedAxis[CanonicalAxisIndex.AXIS_RIGHT_STICK_Y] = rawAxes[5];
+    }
+
+    private static float negativeAxisValueAsButton(float input) {
+        return (input < -0.5f) ? 1.f : 0.f;
+    }
+
+    private static float positiveAxisValueAsButton(float input) {
+        return (input > 0.5f) ? 1.f : 0.f;
+    }
+
+    /**
+    * Method for mapping Nvidia gamepad axis and button values
+    * to standard gamepad button and axes values.
+    */
+    private static void mapShieldGamepad(float[] mappedButtons, float[] rawButtons,
+                                         float[] mappedAxis, float[] rawAxes) {
+        mapCommonButtons(mappedButtons, rawButtons);
+
+        mappedButtons[CanonicalButtonIndex.BUTTON_LEFT_TRIGGER] = rawAxes[2]; // or rawAxes[3];
+        mappedButtons[CanonicalButtonIndex.BUTTON_RIGHT_TRIGGER] = rawAxes[6]; // or rawAxes[7];
+
+        mapDpadButtonsToAxes(mappedButtons, rawAxes);
+        mapAxes(mappedAxis, rawAxes);
+    }
+
+    /**
+    * Method for mapping Microsoft XBox 360 gamepad axis and button values
+    * to standard gamepad button and axes values.
+    */
+    private static void mapXBox360Gamepad(float[] mappedButtons, float[] rawButtons,
+                                          float[] mappedAxis, float[] rawAxes) {
+        mapCommonButtons(mappedButtons, rawButtons);
+
+        mappedButtons[CanonicalButtonIndex.BUTTON_LEFT_TRIGGER] = rawAxes[2]; // or rawAxes[3];
+        mappedButtons[CanonicalButtonIndex.BUTTON_RIGHT_TRIGGER] = rawAxes[6]; // or rawAxes[7];
+
+        mapDpadButtonsToAxes(mappedButtons, rawAxes);
+        mapAxes(mappedAxis, rawAxes);
+    }
+
+    /**
+    * Method for mapping Unkown gamepad axis and button values
+    * to standard gamepad button and axes values.
+    */
+    private static void mapUnkownGamepad(float[] mappedButtons, float[] rawButtons,
+                                 float[] mappedAxis, float[] rawAxes) {
+        mapCommonButtons(mappedButtons, rawButtons);
+
+        mappedButtons[CanonicalButtonIndex.BUTTON_LEFT_TRIGGER] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_L2];
+        mappedButtons[CanonicalButtonIndex.BUTTON_RIGHT_TRIGGER] =
+                            rawButtons[KeyEvent.KEYCODE_BUTTON_R2];
+
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_UP] = rawButtons[KeyEvent.KEYCODE_DPAD_UP];
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_DOWN] =
+                            rawButtons[KeyEvent.KEYCODE_DPAD_DOWN];
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_RIGHT] =
+                            rawButtons[KeyEvent.KEYCODE_DPAD_RIGHT];
+        mappedButtons[CanonicalButtonIndex.BUTTON_DPAD_LEFT] =
+                            rawButtons[KeyEvent.KEYCODE_DPAD_LEFT];
+
+        mapAxes(mappedAxis, rawAxes);
+    }
+
+}