城杆

var carray=new Array();var root;var NUM_CIRCLES=300;var RADIUS=8;var bHighRes=false;var bGravity=false;var bFade=true;var g;var g_texture;var bImagesLoaded=false;var nGeneralWindX=Math.sin(Math.random()*360)*3;var nGeneralWindY=Math.cos(Math.random()*360)*3;var arr_Msg=['h','e','l','l','o'];var nMsgIndex=0;var arr_ImageLetters=new Array();var arr_letters=['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];for(var l=0;l<26;l++){arr_ImageLetters[l]=new Image();arr_ImageLetters[l].src="letters/free-alphabet-clipart-"+arr_letters[l]+".jpg"}function Circle(x,y,r){this.x=x;this.y=y;this.r=r;this.destX=-1;this.destY=-1;this.alpha=0;this.vx=Math.random()-.5*5;this.vy=Math.random()-.5*5}function init(){g=$('#born_canvas')[0].getContext("2d");g_texture=$('#born_canvas_hidden')[0].getContext("2d");WIDTH=$("#born_canvas").width();HEIGHT=$("#born_canvas").height();TEXTURE_WIDTH=$("#born_canvas_hidden").width();TEXTURE_HEIGHT=$("#born_canvas_hidden").height();for(i=0;i<NUM_CIRCLES;i++)carray[i]=new Circle(Math.floor(Math.random()*WIDTH),Math.floor(Math.random()*HEIGHT),RADIUS);return setInterval(draw,30)}function setLetter(c){var nFound=-1;for(var i=0;i<26;i++){if(arr_letters[i]==c){nFound=i}}var nIndex=0;if(nFound>-1){g_texture.fillStyle="#00000000";g_texture.fillRect(0,0,TEXTURE_WIDTH,TEXTURE_HEIGHT);g_texture.drawImage(arr_ImageLetters[nFound],0,0);var imageData=g_texture.getImageData(0,0,TEXTURE_WIDTH,TEXTURE_HEIGHT);var sqWidth=4;if(bHighRes)sqWidth=2;for(j=0;j<Math.floor(imageData.height);j=j+sqWidth){for(i=0;i<Math.floor(imageData.width);i=i+sqWidth){var nAvg=0;for(ypos=j;ypos<j+sqWidth;ypos++){for(xpos=i;xpos<i+sqWidth;xpos++){var index=(xpos*4)*imageData.width+(ypos*4);var red=imageData.data[index];var green=imageData.data[index+1];var blue=imageData.data[index+2];var alpha=imageData.data[index+3];var average=(red+green+blue)/3;nAvg+=average/(sqWidth*sqWidth)}}if(nAvg>60&&nIndex<carray.length){carray[nIndex].destX=(j+Math.floor(sqWidth/2))*1.5+260;carray[nIndex].destY=(i+Math.floor(sqWidth/2))*1.5+130;nIndex++}}}}for(i=nIndex+1;i<carray.length;i++){carray[i].destX=-1;carray[i].destY=-1}}function setNextLetter(){setLetter(arr_Msg[nMsgIndex]);nMsgIndex++;nMsgIndex=nMsgIndex%arr_Msg.length}function clearCircles(){nGeneralWindX=Math.sin(Math.random()*360)*10;nGeneralWindY=Math.cos(Math.random()*360)*10;for(i=0;i<carray.length;i++){var nang=Math.random()*360;carray[i].vx=Math.sin(nang)*5;carray[i].vy=Math.cos(nang)*5;carray[i].destX=-1;carray[i].destY=-1}}

function startClearCircles(){
  setInterval(clearCircles,3000)
}

function draw(){
  
  if(!bImagesLoaded){
    bImagesLoaded=imagesLoaded();
    return;
  }
  
  clear();
  
  var i;
  
  for (i=0; i<carray.length; i++)
  {
  var C=carray[i];  
  
  if(C.destX>-1){
    C.x+=(C.destX-C.x)/4+((C.destX-C.x)/90 * C.vx)+nGeneralWindX;
    C.y+=(C.destY-C.y)/4+((C.destY-C.y)/90 * C.vy)+nGeneralWindY;
    C.alpha+=(.1-C.alpha)/2;
  }
  else{    
    C.x+=C.vx+nGeneralWindX;
    C.y+=C.vy+nGeneralWindY;
    if(bGravity)
    C.vy+=1.0;
    if(bFade)
      C.alpha*=(.9+C.alpha)*.98
    if(C.alpha<0)C.alpha=0;
  }
  
  nGeneralWindX*=.9999;
  nGeneralWindY*=.9999;
  
  
  if(C.x<0){C.x=-C.x;C.vx=-C.vx;}
  if(C.y<0){C.y=-C.y;C.vy=-C.vy;};
  if(C.x>WIDTH){C.x=WIDTH-(C.x-WIDTH);C.vx=-C.vx;}
  if(C.y>HEIGHT){C.y=HEIGHT-(C.y-HEIGHT);C.vy=-C.vy*.45;}
  
  
  
  g.globalAlpha=C.alpha;
  g.beginPath();
  g.fillStyle = "#FFFFFF";
  g.arc(C.x, C.y, C.r, 0, Math.PI*2, true);
  g.closePath();
  g.fill();
    
  }
  

}
  function imagesLoaded(){for(i=0;i<26;i++){if(!arr_ImageLetters[i].complete)return false}setTimeout(startClearCircles,1500);setInterval(setNextLetter,3000);return true}function clear(){g.globalAlpha=.1;g.fillStyle="#000000";g.fillRect(0,0,WIDTH,HEIGHT)}function changeMessage(){var txtVal=($("#message").val()).toLowerCase();arr_Msg=txtVal;nMsgIndex=0;strMsg=$("#message").val();var regNoNumbers=new RegExp("([^a-z ])*","gi");strMsg=strMsg.replace(regNoNumbers,"");$("#urlText").html("http://www.feedtank.com/labs/html_canvas/?msg="+escape(strMsg))}function setHighNumCircles(){NUM_CIRCLES=1500;bHighRes=true;delete carray;($("#radio_Low")).attr("checked","false");($("#radio_High")).attr("checked","true");carray=new Array();RADIUS=3;for(i=0;i<NUM_CIRCLES;i++)carray[i]=new Circle(Math.floor(Math.random()*WIDTH),Math.floor(Math.random()*HEIGHT),RADIUS)}function setMinNumCircles(){NUM_CIRCLES=300;bHighRes=false;RADIUS=8;($("#radio_Low")).attr("checked","true");($("#radio_High")).attr("checked","false");delete carray;carray=new Array();for(i=0;i<NUM_CIRCLES;i++)carray[i]=new Circle(Math.floor(Math.random()*WIDTH),Math.floor(Math.random()*HEIGHT),RADIUS)}function setGravity(){bGravity=!bGravity}function setFade(){bFade=!bFade}$(document).ready(function(){init()});