在Libgdx中定位和旋转动画

当你有一个开始状态和一个结束状态,并且你想要填充中间状态时,这被称为“tweening(来自中间)。它来自卡通动画,但已被广泛使用。

LibGDX使用通用Tween引擎。你可以开始制作任何你想要的动画 here

首先,你需要一个TweenAccessor来完成你想要的tween课程。

public class RenderNodeTweenAccessor implements TweenAccessor<JJRenderNode> {


public static final int WIDTH = 1;
public static final int HEIGHT = 2;
public static final int WIDTH_HEIGHT = 3;
public static final int ALPHA = 4;
public static final int ALPHA_WIDTH_HEIGHT=5;

@Override
public int getValues(JJRenderNode target, int tweenType, float[] returnValues) {
    switch (tweenType) {
        case WIDTH:
            returnValues[0] = target.getWidth();
            return 1;
        case HEIGHT:
            returnValues[0] = target.getHeight();
            return 1;
        case WIDTH_HEIGHT:
            returnValues[0] = target.getWidth();
            returnValues[1] = target.getHeight();
            return 2;
        case ALPHA:
            returnValues[0] = target.getColour().a;
            return 1;
        case ALPHA_WIDTH_HEIGHT:
            returnValues[0] = target.getColour().a;
            returnValues[1] = target.getWidth();
            returnValues[2] = target.getHeight();
            return 3;
        default:
            assert false;
            return -1;
    }
}

@Override
public void setValues(JJRenderNode target, int tweenType, float[] newValues) {
    switch (tweenType) {
        case WIDTH:
            target.setWidth(newValues[0]);
            break;
        case HEIGHT:
            target.setHeight(newValues[0]);
            break;
        case WIDTH_HEIGHT:
            target.setWidth(newValues[0]);
            target.setHeight(newValues[1]);
            break;
        case ALPHA:
            target.getColour().a=newValues[0];
            break;
        case ALPHA_WIDTH_HEIGHT:
            target.getColour().a=newValues[0];
            target.setWidth(newValues[1]);
            target.setHeight(newValues[2]);
        default:
            break;
    }
}
}

您必须按以下方式注册此TweenAccessor:

Tween.registerAccessor(JJRenderNode.class, new RenderNodeTweenAccessor());

Timeline.createSequence()
                .push(Tween.set(node, RenderNodeTweenAccessor.WIDTH_HEIGHT).target(START_WIDTH, START_WIDTH))
                .push(Tween.to(node, RenderNodeTweenAccessor.WIDTH_HEIGHT, 0.4f).target(PuzzleBlockCore.MAX_RENDER_WIDTH, PuzzleBlockCore.MAX_RENDER_WIDTH))
                .start(JJ.tweenManager);

另外,你还需要一个TweenManger的实例,这需要为每个gameloop更新delta。我有一个“单例”全局实例,我在任何地方都使用它(JJ.TweenManager)。

http://esotericsoftware.com/

private void render() {
   sprite.set(aninationframes.get(currentFrame)
   currentFrame = currentFrame + 1} 

不过,您可能需要为每帧添加延迟。

If(current time - time > some value) {
   sprite.set(animationframes.get(currrntFrame)
   currentFrame = currentFrame + 1
   time = get current time here
}