feat: AnimationTexture can start from a given frame, part of #1244, c…

…o-author: @chengenzhao

fxgl-core/src/main/kotlin/com/almasb/fxgl/texture/AnimatedTexture.kt

@@ -50,7 +50,7 @@ class AnimatedTexture(defaultChannel: AnimationChannel) : Texture(defaultChannel
 
     /**
      * Plays given animation [channel] from start to end once.
-     * The animation will stop at the last frame.
+     * The animation will stop on the last frame.
      */
     fun playAnimationChannel(channel: AnimationChannel) {
         animationChannel = channel
@@ -60,6 +60,17 @@ class AnimatedTexture(defaultChannel: AnimationChannel) : Texture(defaultChannel
         animation.start()
     }
 
+    /**
+     * Plays given animation [channel] from specific [startFrame] to end once.
+     * The animation will stop on the last frame.
+     */
+    fun playAnimationChannel(channel: AnimationChannel, startFrame: Int) {
+        playAnimationChannel(channel)
+
+        currentFrame = startFrame
+        animation.setTimeTo(currentFrame.toDouble() * animationChannel.frameDuration)
+    }
+
     /**
      * Loops given [channel].
      *
@@ -117,6 +128,15 @@ class AnimatedTexture(defaultChannel: AnimationChannel) : Texture(defaultChannel
         return this
     }
 
+    /**
+     * Play the last animation channel (or default) from specific [startFrame] to end once.
+     * The animation will stop on the last frame.
+     */
+    fun playFrom(startFrame: Int): AnimatedTexture {
+        playAnimationChannel(animationChannel, startFrame)
+        return this
+    }
+
     /**
      * Loops the last animation channel (or default).
      */

fxgl-samples/src/main/java/intermediate/animation/AnimatedTextureSample.java

@@ -0,0 +1,128 @@
+/*
+ * FXGL - JavaFX Game Library. The MIT License (MIT).
+ * Copyright (c) AlmasB (almaslvl@gmail.com).
+ * See LICENSE for details.
+ */
+
+package intermediate.animation;
+
+import com.almasb.fxgl.animation.Interpolators;
+import com.almasb.fxgl.app.GameApplication;
+import com.almasb.fxgl.app.GameSettings;
+import com.almasb.fxgl.texture.AnimatedTexture;
+import com.almasb.fxgl.texture.AnimationChannel;
+import javafx.animation.Interpolator;
+import javafx.scene.control.Button;
+import javafx.scene.control.Spinner;
+import javafx.scene.layout.VBox;
+import javafx.scene.paint.Color;
+import javafx.scene.text.Font;
+import javafx.util.Duration;
+
+import static com.almasb.fxgl.dsl.FXGL.*;
+
+/**
+ * @author Almas Baimagambetov (almaslvl@gmail.com)
+ */
+public class AnimatedTextureSample extends GameApplication {
+    @Override
+    protected void initSettings(GameSettings settings) {
+        settings.setWidth(1480);
+        settings.setHeight(1020);
+    }
+
+    @Override
+    protected void initGame() {
+        getGameScene().setBackgroundColor(Color.BLACK);
+
+        var interpolators = Interpolators.values();
+
+        for (int i = 0; i < interpolators.length; i++) {
+            var x = i % 7;
+            var y = i / 7;
+
+            spawnRobot(x * 150, y * 360, interpolators[i].EASE_OUT(), interpolators[i].toString());
+        }
+
+        spawnRobot(0, 360 * 2, false, false);
+        spawnRobot(160, 360 * 2, true, false);
+        spawnRobot(320, 360 * 2, false, true);
+        spawnRobot(480, 360 * 2, true, true);
+    }
+
+    @Override
+    protected void initUI() {
+        var frameSpinner = new Spinner<Integer>(0, 23, 0);
+        frameSpinner.setPrefWidth(100);
+
+        var btn = new Button("Play from frame");
+        btn.setOnAction(e -> {
+            spawnRobotForFrame(900, 700, frameSpinner.getValue());
+        });
+
+        var vbox = new VBox(10, frameSpinner, btn);
+
+        addUINode(vbox, 1230, 820);
+    }
+
+    private void spawnRobotForFrame(double x, double y, int startFrame) {
+        var animChannel = new AnimationChannel(image("robot_roll.png"), 7, 275, 275, Duration.seconds(2.6), 0, 23);
+        var animTexture = new AnimatedTexture(animChannel);
+        animTexture.playFrom(startFrame);
+
+        var e = entityBuilder()
+                .at(x, y)
+                .view(animTexture)
+                .buildAndAttach();
+
+        animTexture.setOnCycleFinished(() -> e.removeFromWorld());
+    }
+
+    private void spawnRobot(double x, double y, Interpolator interpolator, String name) {
+        var text = addText(name, x + 120, y + 30);
+        text.fontProperty().unbind();
+        text.setFont(Font.font(18));
+
+        var animChannel = new AnimationChannel(image("robot_roll.png"), 7, 275, 275, Duration.seconds(2.6), 0, 23);
+        var animTexture = new AnimatedTexture(animChannel);
+        animTexture.setInterpolator(interpolator);
+        animTexture.loop();
+
+        entityBuilder()
+                .at(x, y)
+                .view(animTexture)
+                .buildAndAttach();
+    }
+
+    private void spawnRobot(double x, double y, boolean isReverse, boolean isLoop) {
+        var text = addText(isReverse ? "Reverse" : "Play", x + 120, y + 30);
+        text.fontProperty().unbind();
+        text.setFont(Font.font(18));
+
+        var animChannel = new AnimationChannel(image("robot_death.png"), 7, 275, 275, Duration.seconds(2.6), 0, 26);
+        var animTexture = new AnimatedTexture(animChannel);
+
+        if (isLoop) {
+            if (isReverse) {
+                animTexture.loopReverse();
+            } else {
+                animTexture.loop();
+            }
+        } else {
+            if (isReverse) {
+                animTexture.playReverse();
+            } else {
+                animTexture.play();
+            }
+        }
+
+        entityBuilder()
+                .at(x, y)
+                .view(animTexture)
+                .buildAndAttach();
+    }
+
+    public static void main(String[] args) {
+        launch(args);
+    }
+}