• 基本动作
    • 移动
    • 旋转
    • 缩放
      • 淡入淡出
    • 色彩混合
    • 帧动画
    • 变速运动

    基本动作

    基本动作通常都是单一的动作,用来完成一个简单的目标。下面通过简单的示例来介绍常见的基本动作。

    移动

    使用 MoveTo MoveBy 完成节点对象在一个设置的时间后移动。

    1. auto mySprite = Sprite::create("mysprite.png");
    2. // Move a sprite to a specific location over 2 seconds.
    3. auto moveTo = MoveTo::create(2, Vec2(50, 0));
    4. mySprite->runAction(moveTo);
    5. // Move a sprite 50 pixels to the right, and 0 pixels to the top over 2 seconds.
    6. auto moveBy = MoveBy::create(2, Vec2(50, 0));
    7. mySprite->runAction(moveBy);

    基本动作  - 图1

    旋转

    使用 RotateTo RotateBy 完成节点对象在一个设置的时间后顺时针旋转指定角度。

    1. auto mySprite = Sprite::create("mysprite.png");
    2. // Rotates a Node to the specific angle over 2 seconds
    3. auto rotateTo = RotateTo::create(2.0f, 40.0f);
    4. mySprite->runAction(rotateTo);
    5. // Rotates a Node clockwise by 40 degree over 2 seconds
    6. auto rotateBy = RotateBy::create(2.0f, 40.0f);
    7. mySprite->runAction(rotateBy);

    基本动作  - 图2

    缩放

    使用 ScaleBy ScaleTo 完成节点对象的比例缩放。

    1. auto mySprite = Sprite::create("mysprite.png");
    2. // Scale uniformly by 3x over 2 seconds
    3. auto scaleBy = ScaleBy::create(2.0f, 3.0f);
    4. mySprite->runAction(scaleBy);
    5. // Scale X by 5 and Y by 3x over 2 seconds
    6. auto scaleBy = ScaleBy::create(2.0f, 3.0f, 3.0f);
    7. mySprite->runAction(scaleBy);
    8. // Scale to uniformly to 3x over 2 seconds
    9. auto scaleTo = ScaleTo::create(2.0f, 3.0f);
    10. mySprite->runAction(scaleTo);
    11. // Scale X to 5 and Y to 3x over 2 seconds
    12. auto scaleTo = ScaleTo::create(2.0f, 3.0f, 3.0f);
    13. mySprite->runAction(scaleTo);

    基本动作  - 图3

    淡入淡出

    使用 FadeIn FadeOut 完成节点对象的淡入,淡出。 FadeIn 修改节点对象的透明度属性,从完全透明到完全不透明,FadeOut 相反。

    1. auto mySprite = Sprite::create("mysprite.png");
    2. // fades in the sprite in 1 seconds
    3. auto fadeIn = FadeIn::create(1.0f);
    4. mySprite->runAction(fadeIn);
    5. // fades out the sprite in 2 seconds
    6. auto fadeOut = FadeOut::create(2.0f);
    7. mySprite->runAction(fadeOut);

    基本动作  - 图4

    色彩混合

    使用 TintTo TintBy,将一个实现了 NodeRGB 协议的节点对象进行色彩混合。

    1. auto mySprite = Sprite::create("mysprite.png");
    2. // Tints a node to the specified RGB values
    3. auto tintTo = TintTo::create(2.0f, 120.0f, 232.0f, 254.0f);
    4. mySprite->runAction(tintTo);
    5. // Tints a node BY the delta of the specified RGB values.
    6. auto tintBy = TintBy::create(2.0f, 120.0f, 232.0f, 254.0f);
    7. mySprite->runAction(tintBy);

    基本动作  - 图5

    帧动画

    使用 Animate 对象可以很容易的通过每隔一个短暂时间进行图像替代的方式,实现一个翻页效果。下面是一个例子:

    1. auto mySprite = Sprite::create("mysprite.png");
    2. // now lets animate the sprite we moved
    3. Vector<SpriteFrame*> animFrames;
    4. animFrames.reserve(12);
    5. animFrames.pushBack(SpriteFrame::create("Blue_Front1.png", Rect(0,0,65,81)));
    6. animFrames.pushBack(SpriteFrame::create("Blue_Front2.png", Rect(0,0,65,81)));
    7. animFrames.pushBack(SpriteFrame::create("Blue_Front3.png", Rect(0,0,65,81)));
    8. animFrames.pushBack(SpriteFrame::create("Blue_Left1.png", Rect(0,0,65,81)));
    9. animFrames.pushBack(SpriteFrame::create("Blue_Left2.png", Rect(0,0,65,81)));
    10. animFrames.pushBack(SpriteFrame::create("Blue_Left3.png", Rect(0,0,65,81)));
    11. animFrames.pushBack(SpriteFrame::create("Blue_Back1.png", Rect(0,0,65,81)));
    12. animFrames.pushBack(SpriteFrame::create("Blue_Back2.png", Rect(0,0,65,81)));
    13. animFrames.pushBack(SpriteFrame::create("Blue_Back3.png", Rect(0,0,65,81)));
    14. animFrames.pushBack(SpriteFrame::create("Blue_Right1.png", Rect(0,0,65,81)));
    15. animFrames.pushBack(SpriteFrame::create("Blue_Right2.png", Rect(0,0,65,81)));
    16. animFrames.pushBack(SpriteFrame::create("Blue_Right3.png", Rect(0,0,65,81)));
    17. // create the animation out of the frames
    18. Animation* animation = Animation::createWithSpriteFrames(animFrames, 0.1f);
    19. Animate* animate = Animate::create(animation);
    20. // run it and repeat it forever
    21. mySprite->runAction(RepeatForever::create(animate));

    变速运动

    变速动作可以让节点对象具有加速度,产生平滑同时相对复杂的动作,所以可以用变速动作来模仿一些物理运动,这样比实际使用物理引擎的性能消耗低,使用起来也简单。当然你也可以将变速动作应用到动画菜单和按钮上,实现你想要的效果。

    基本动作  - 图6

    Cocos2d-x 支持上图中的大部分变速动作,实现起来也很简单。我们来看个例子,一个精灵从屏幕顶部落下然后不断跳动:

    1. // create a sprite
    2. auto mySprite = Sprite::create("mysprite.png");
    3. // create a MoveBy Action to where we want the sprite to drop from.
    4. auto move = MoveBy::create(2, Vec2(200, dirs->getVisibleSize().height -
    5. newSprite2->getContentSize().height));
    6. // create a BounceIn Ease Action
    7. auto move_ease_in = EaseBounceIn::create(move->clone() );
    8. auto move_ease_in_back = move_ease_in->reverse();
    9. // create a delay that is run in between sequence events
    10. auto delay = DelayTime::create(0.25f);
    11. // create the sequence of actions, in the order we want to run them
    12. auto seq1 = Sequence::create(move_ease_in, delay, move_ease_in_back,
    13. delay->clone(), nullptr);
    14. // run the sequence and repeat forever.
    15. mySprite->runAction(RepeatForever::create(seq1));

    复杂的动作很难在这样的文本里表示,要是看效果的话最好去运行一下本指南的 代码示例,或者运行引擎代码的测试项目 cpp-tests,在子菜单 3:Actions - Basic 中有基本的动作效果展示。

    运行测试项目的方法,参考本文档的 环境搭建 章节 .