opt: API of canvas

autojs/src/main/java/com/stardust/autojs/core/graphics/ScriptCanvas.java

@@ -1,6 +1,7 @@
 package com.stardust.autojs.core.graphics;
 
 import android.graphics.Bitmap;
+import android.graphics.Canvas;
 import android.graphics.DrawFilter;
 import android.graphics.Matrix;
 import android.graphics.Paint;
@@ -17,28 +18,35 @@ import android.support.annotation.RequiresApi;
 
 import com.stardust.autojs.core.image.ImageWrapper;
 import com.stardust.autojs.runtime.ScriptRuntime;
-import com.stardust.autojs.runtime.exception.ScriptException;
 
 /**
  * Created by Stardust on 2018/3/22.
  */
 
-public class Canvas {
+public class ScriptCanvas {
 
-    private final android.graphics.Canvas mCanvas;
+    private android.graphics.Canvas mCanvas;
 
-    public Canvas(android.graphics.Canvas canvas) {
+    public ScriptCanvas(android.graphics.Canvas canvas) {
         mCanvas = canvas;
     }
 
-    public Canvas(@NonNull Bitmap bitmap) {
+    public ScriptCanvas(@NonNull Bitmap bitmap) {
         mCanvas = new android.graphics.Canvas(bitmap);
     }
 
-    public Canvas(@NonNull ImageWrapper image) {
+    public ScriptCanvas(@NonNull ImageWrapper image) {
         this(image.getBitmap());
     }
 
+    public ScriptCanvas() {
+
+    }
+
+    void setCanvas(Canvas canvas) {
+        mCanvas = canvas;
+    }
+
     public boolean isHardwareAccelerated() {
         return mCanvas.isHardwareAccelerated();
     }

autojs/src/main/java/com/stardust/autojs/core/graphics/ScriptCanvasView.java

@@ -4,16 +4,17 @@ import android.annotation.SuppressLint;
 import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Color;
+import android.os.SystemClock;
 import android.util.Log;
 import android.view.SurfaceHolder;
 import android.view.SurfaceView;
 
 import com.stardust.autojs.core.eventloop.EventEmitter;
 import com.stardust.autojs.runtime.ScriptRuntime;
+import com.stardust.autojs.runtime.exception.ScriptInterruptedException;
 
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
-import java.util.concurrent.ThreadPoolExecutor;
 
 /**
  * Created by Stardust on 2018/3/16.
@@ -28,6 +29,7 @@ public class ScriptCanvasView extends SurfaceView implements SurfaceHolder.Callb
     private final SurfaceHolder mHolder;
     private ExecutorService mDrawingThreadPool;
     private ScriptRuntime mScriptRuntime;
+    private volatile long mTimePerDraw = 1000 / 30;
 
     public ScriptCanvasView(Context context, ScriptRuntime scriptRuntime) {
         super(context);
@@ -37,6 +39,15 @@ public class ScriptCanvasView extends SurfaceView implements SurfaceHolder.Callb
         init();
     }
 
+
+    public void setMaxFps(int maxFps) {
+        if (maxFps <= 0) {
+            mTimePerDraw = 0;
+        } else {
+            mTimePerDraw = 100 / maxFps;
+        }
+    }
+
     private void init() {
         mHolder.addCallback(this);
     }
@@ -59,13 +70,21 @@ public class ScriptCanvasView extends SurfaceView implements SurfaceHolder.Callb
         mDrawingThreadPool.execute(() -> {
             Canvas canvas = null;
             SurfaceHolder holder = getHolder();
+            long time = SystemClock.uptimeMillis();
+            ScriptCanvas scriptCanvas = new ScriptCanvas();
             try {
                 while (mDrawing) {
                     canvas = holder.lockCanvas();
-                    canvas.drawColor(Color.WHITE);
+                    scriptCanvas.setCanvas(canvas);
-                    emit("draw", canvas, this);
+                    scriptCanvas.drawColor(Color.WHITE);
+                    emit("draw", scriptCanvas, this);
                     holder.unlockCanvasAndPost(canvas);
                     canvas = null;
+                    long dt = mTimePerDraw - (SystemClock.uptimeMillis() - time);
+                    if (dt > 0) {
+                        sleep(dt);
+                    }
+                    time = SystemClock.uptimeMillis();
                 }
             } catch (Exception e) {
                 mScriptRuntime.exit(e);
@@ -78,6 +97,14 @@ public class ScriptCanvasView extends SurfaceView implements SurfaceHolder.Callb
         });
     }
 
+    private void sleep(long dt) {
+        try {
+            Thread.sleep(dt);
+        } catch (InterruptedException e) {
+            throw new ScriptInterruptedException(e);
+        }
+    }
+
     @Override
     protected void onWindowVisibilityChanged(int visibility) {
         Log.d(LOG_TAG, "onWindowVisibilityChanged: " + this + ": visibility=" + visibility + ", mDrawingThreadPool=" + mDrawingThreadPool);