前几天的一篇文章，用Flash轻松制作电子发散视觉效果动画好多人都问有什么用？今天就再继续一下！看看红外线引导导弹爆炸效果。
爆炸的代码我们还使用前面那个教程中用到的代码，在这个效果里，我们首先把光标的形状变换一下，然后点鼠标就有一个导弹出现，然后发生爆炸。
新建立一个文件，按Ctrl+J调整大小和背景色(#999999)和帧频。
然后制作一个红色的小圆影片剪辑作为鼠标的形状，制作一条有色的线条影片剪辑作为导弹，然后再制作一个白色小圆作为爆炸的影片剪辑。
然后在第一帧加入如下代码。
/* GLOBAL VARIABLES */
_global.gLEFT = 20;
_global.gTOP = 20;
_global.gRIGHT = Stage.width - 20;
_global.gBOTTOM = Stage.height - 20;
/* FUNCTION: Converts radians to degrees */
function rad2deg(radians:Number):Number {
return radians * 180 / Math.PI;
}
/* FUNCTION: Converts degrees to radians */
function deg2rad(degrees:Number):Number {
return degrees * Math.PI / 180;
}
/* FUNCTION: Returns a random number between min and max (inclusive) */
function randRange(min:Number, max:Number):Number {
var randomNum:Number = Math.floor(Math.random() * (max - min + 1)) + min;
return randomNum;
}
/* FUNCTION: Creates an explosion */
explosion.maxSpeed = 25;
explosion.minSize = 4;
explosion.maxSize = 10;
explosion.minFragments = 10;
explosion.maxFragments = 50;
function explosion(originX:Number, originY:Number):Void {
var totalFragments:Number = randRange(explosion.minFragments, explosion.maxFragments);
var fragment_mc:MovieClip;
var depth:Number = this.getNextHighestDepth();
for (var i:Number = 0; i < totalFragments; i++, depth++) {
fragment_mc = attachMovie("Fragment", "fragment" + depth, depth);
fragment_mc._x = originX;
fragment_mc._y = originY;
fragment_mc._width = fragment_mc._height = randRange(explosion.minSize, explosion.maxSize);
while (!fragment_mc.speedX) {
fragment_mc.speedX = randRange(-explosion.maxSpeed, explosion.maxSpeed);
}
while (!fragment_mc.speedY) {
fragment_mc.speedY = randRange(-explosion.maxSpeed, explosion.maxSpeed);
}
fragment_mc._alpha = randRange(10, 100);
fragment_mc.cacheAsBitmap = true;
fragment_mc.onEnterFrame = function():Void {
this._x += this.speedX;
this._y += this.speedY;
if (this._x < gLEFT this._x > gRIGHT this._y < gTOP this._y > gBOTTOM) {
this.removeMovieClip();
}
};
}
}
/* FUNCTION: Creates and initializes heat-seeking missiles */
createMissile.maxSpeed = 30;
createMissile.accel = 2;
function createMissile(target_mc:MovieClip, xPos:Number, yPos:Number):Void {
var depth:Number = _root.getNextHighestDepth();
var missile_mc:MovieClip = attachMovie("Missile", "missile" + depth, depth);
missile_mc._x = xPos;
missile_mc._y = yPos;
missile_mc.speed = 0;
missile_mc.setRotation = function():Void {
var dy:Number = target_mc._y - this._y;
var dx:Number = target_mc._x - this._x;
this._rotation = rad2deg(Math.atan2(dy, dx));
};
missile_mc.onEnterFrame = function():Void {
this.setRotation();
if (this.speed < createMissile.maxSpeed) {
this.speed += createMissile.accel;
}
this._x += Math.cos(deg2rad(this._rotation)) * this.speed;
this._y += Math.sin(deg2rad(this._rotation)) * this.speed;
if (this.hitTest(target_mc)) {
explosion(target_mc._x, target_mc._y);
this.removeMovieClip();
}
};
}
/* MAIN PROGRAM LOGIC */
var gameBG_mc:MovieClip = _root.createEmptyMovieClip("gameBG", 0);
gameBG_mc.beginFill(0x222222);
gameBG_mc.moveTo(gLEFT, gTOP);
gameBG_mc.lineTo(gRIGHT, gTOP);
gameBG_mc.lineTo(gRIGHT, gBOTTOM);
gameBG_mc.lineTo(gLEFT, gBOTTOM);
gameBG_mc.endFill(gLEFT, gTOP);
var target_mc:MovieClip = attachMovie("Target", "target", _root.getNextHighestDepth());
var startX:Number = (gRIGHT - gLEFT) / 2 + gLEFT;
var startY:Number = (gBOTTOM - gTOP) / 2 + gTOP;
startDrag(target_mc, true);
Mouse.hide();
onMouseDown = function():Void {
createMissile(target_mc, startX, startY);
};
