这是我的结构
Layer:
ParentGroup:
-Kinetic Image
-ChildGroup
- Kinetic rectangle
- Kinetic Text
在我的动态图像(我从服务器检索)上,有一个感兴趣的区域。这个感兴趣的区域用矩形表示(这里是动力矩形)。我在这个区域内写了一些标签(这是动态文本)。
我想对整个小组应用一些操作。翻译还可以,但我有缩放和旋转方面的问题。这是我的缩放功能
function zoomIn() {
var scale=parentGroup.getScale();
scale.x *= zoomFactor; //zoomFactor is a global variable
scale.y *= zoomFactor;
parentGroup.setScale(scale);
layer.draw()
}
这里发生的事情是该组被放大但同时翻译(向右和向下)。如果我继续缩放,图像会从画布中移出。
我在绘制图层之前尝试过:parentGroup.setPosition (0,0);
//虽然我知道我从未修改过这个位置,但没有任何改变。
我在这里阅读KineticJS Canvas - Scale group from center point,这可能是缩放中心的问题。但由于我没有为parentGroup设置任何高度或宽度,我不知道如何调整我的代码。
我现在有什么问题?
答案 0 :(得分:2)
KineticJS:如何缩放,旋转和拖动组
[基于对提问者需求的更好理解,简化了原始答案]
编码变得更加简单,因为您允许组的注册点成为其中心点。
注册点是比例变换的缩放点和旋转的旋转点。
以下是如何将注册点设置为组的中心:
// set the group offset to the group’s centerpoint
parentGroup.setOffset(parentGroup.getWidth()/2,parentGroup.getHeight()/2);
设置注册点后,只需正常使用group.setScale和group.rotateDeg:
// scale the group from its centerpoint
parentGroup.setScale(parentGroup.getScale().x+0.10);
// rotate the group at its centerpoint
parentGroup.rotateDeg(30);
这是代码和小提琴:http://jsfiddle.net/m1erickson/XWW7Z/
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
<script src="http://d3lp1msu2r81bx.cloudfront.net/kjs/js/lib/kinetic-v4.5.4.min.js"></script>
<style>
body{ padding:15px; }
#container{
border:solid 1px #ccc;
margin-top: 10px;
width:400px;
height:400px;
}
</style>
<script>
$(function(){
var stage = new Kinetic.Stage({
container: 'container',
width: 400,
height: 400
});
var layer = new Kinetic.Layer();
stage.add(layer);
// parentGroup is used in jquery events
// so make it global
var parentGroup;
// load the image and then start the app
var image=new Image();
image.onload=function(){
start();
}
image.src="https://dl.dropboxusercontent.com/u/139992952/stackoverflow/house-icon.png";
// build everything, wire events
function start(){
parentGroup=new Kinetic.Group({
x:image.width/2,
y:image.height/2,
width:image.width,
height:image.height,
draggable:true
});
parentGroup.setOffset(parentGroup.getWidth()/2,parentGroup.getHeight()/2);
layer.add(parentGroup);
var kImage=new Kinetic.Image({
image:image,
x:0,
y:0,
width:image.width,
height:image.height
});
parentGroup.add(kImage);
var childGroup=new Kinetic.Group({
x:0,
y:0,
width:100,
height:50
});
parentGroup.add(childGroup);
// this outline rect is just for illustration
var boundingRect=new Kinetic.Rect({
x:0,
y:0,
width:parentGroup.getWidth(),
height:parentGroup.getHeight(),
stroke:"black",
strokeWidth:.75
});
parentGroup.add(boundingRect);
var childRect=new Kinetic.Rect({
x:0,
y:0,
width:105,
height:25,
stroke:"lightgray",
fill:"skyblue"
});
childGroup.add(childRect);
var childText=new Kinetic.Text({
x:5,
y:3,
fontSize:18,
text:"Hello, World",
fill:"blue"
});
childGroup.add(childText);
layer.draw();
// scale up by +0.10 at parentGroup registration point
$("#larger").click(function(){
parentGroup.setScale(parentGroup.getScale().x+0.10);
layer.draw();
});
// scale down by +0.10 at parentGroup registration point
$("#smaller").click(function(){
parentGroup.setScale(parentGroup.getScale().x-0.10);
layer.draw();
});
// rotate CW by 30 degrees at parentGroup registration point
$("#rotateCW").click(function(){
parentGroup.rotateDeg(30);
layer.draw();
});
// rotate CCW by 30 degrees at parentGroup registration point
$("#rotateCCW").click(function(){
parentGroup.rotateDeg(-30);
layer.draw();
});
}
}); // end $(function(){});
</script>
</head>
<body>
<button id="larger">Larger</button>
<button id="smaller">Smaller</button>
<button id="rotateCW">Rotate clockwise</button>
<button id="rotateCCW">Rotate CCW</button>
<div id="container"></div>
</body>
</html>