update

software/android/app/src/main/java/com/rookiedev/hexapod/ControlActivity.kt

@@ -1,9 +1,18 @@
 package com.rookiedev.hexapod
 
-import androidx.appcompat.app.AppCompatActivity
+import android.annotation.SuppressLint
+import android.content.res.Resources
 import android.os.Bundle
-import android.view.WindowInsets
-import android.view.WindowInsetsController
+import android.util.TypedValue
+import android.view.*
+import android.widget.ImageView
+import androidx.appcompat.app.AppCompatActivity
+import java.lang.Math.min
+import kotlin.math.pow
+import kotlin.math.sqrt
+import kotlin.math.atan2
+import kotlin.math.PI
+
 
 /**
  * Behaviors of immersive mode.
@@ -53,13 +62,96 @@ enum class TypeOption(
 }
 
 class ControlActivity : AppCompatActivity() {
+    private var pxMargin = 0f
+    private var width = 0
+    private var height = 0
+    private var radius = 0f
+
+    @SuppressLint("ClickableViewAccessibility")
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_control)
 
         controlWindowInsets(true)
+
+        val controlCircle = findViewById<ImageView>(R.id.control_image)
+
+        val dip = 32f
+        val r: Resources = resources
+        this.pxMargin = TypedValue.applyDimension(
+            TypedValue.COMPLEX_UNIT_DIP,
+            dip,
+            r.displayMetrics
+        )
+
+        val vto: ViewTreeObserver = controlCircle.viewTreeObserver
+        vto.addOnPreDrawListener(object : ViewTreeObserver.OnPreDrawListener {
+            override fun onPreDraw(): Boolean {
+                controlCircle.viewTreeObserver.removeOnPreDrawListener(this)
+                height = controlCircle.measuredHeight
+                width = controlCircle.measuredWidth
+                radius = width.coerceAtMost(height) / 2f
+                println(radius)
+                return true
+            }
+        })
+
+        controlCircle.setOnTouchListener(
+            object : View.OnTouchListener {
+                override fun onTouch(view: View, motionEvent: MotionEvent): Boolean {
+                    val touchX = motionEvent.x
+                    val touchY = motionEvent.y
+                    if (touchX < 0) {
+                        return false
+                    }
+                    if (touchY < 0) {
+                        return false
                     }
 
+                    val coorX = touchX - width / 2
+                    val coorY = touchY - height / 2
+
+                    val length = sqrt(coorX.pow(2) + coorY.pow(2))
+                    if (length < radius / 3) {
+                        println("Standby")
+                    } else if (length >= radius / 3 && length < 2 * radius / 3) {
+                        var angle = atan2(coorY, coorX)
+                        if (angle>-PI/4 && angle<=PI/4)
+                        {
+                            println("Move right")
+                        } else if ( angle>PI/4 && angle<=3*PI/4){
+                            println("Move back")
+                        } else if ( angle>-3*PI/4 && angle<-PI/4){
+                            println("Move forward")
+                        } else {
+                            println("Move left")
+                        }
+                    } else if (length >= 2 * radius / 3 && length < radius) {
+                        var angle = atan2(coorY, coorX)
+                        if (angle>-PI/4 && angle<=PI/4)
+                        {
+                            println("Turn right")
+                        } else if ( angle>PI/4 && angle<=3*PI/4){
+                            println("Fast back")
+                        } else if ( angle>-3*PI/4 && angle<-PI/4){
+                            println("Fast forward")
+                        } else {
+                            println("Turn left")
+                        }
+                    }
+//                    val width = view.width
+//                    val height = view.height
+//                    println(width.toString().plus(":").plus(height.toString()))
+//                    println(touchX.toString().plus(":").plus(touchY.toString()))
+//                    println(coorX.toString().plus(":").plus(coorY.toString()))
+//                    println(radius)
+                    return true
+                }
+            }
+        )
+    }
+
+
     private fun controlWindowInsets(hide: Boolean) {
         // WindowInsetsController can hide or show specified system bars.
         val insetsController = window.decorView.windowInsetsController ?: return

software/android/app/src/main/res/layout/activity_control.xml

@@ -78,7 +78,7 @@
         android:layout_weight="1">
 
         <ImageView
-            android:id="@+id/imageView"
+            android:id="@+id/control_image"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:layout_marginStart="32dp"