Javascript 如何允许在网格上的点之间绘制向量?
在基本上只是Python和C#之后,我目前正在努力过渡到HTML5和Java 我正在(尝试)制作一个点网格,见下面的代码,在点击点之间画线(见下面的代码),最终结果是我可以用它绘制出一个平面图(我是一个建筑商) 我还试图找出如何删除单独绘制的线,而不必按下“重置”按钮,可能通过右键单击它们 不管怎么说,由于是如此新,这让我头痛不已。我一直在摆弄paper.js和jquery,现在已经好几天没有什么运气了 你们中有谁能给我指出一个正确的方向,给我一个我想要的教程/例子,或者给我一些关于在哪里寻求帮助的建议吗 如果做不到这一点,人们如何在这个网格上“点击”一个“点”,并使其对应于向量的起点和终点 我已经包括了我在下面工作的代码 点网格: Vector,使用paper.js(根据此处的教程制作,最终结果在页面底部):Javascript 如何允许在网格上的点之间绘制向量?,javascript,jquery,html,svg,html5-canvas,Javascript,Jquery,Html,Svg,Html5 Canvas,在基本上只是Python和C#之后,我目前正在努力过渡到HTML5和Java 我正在(尝试)制作一个点网格,见下面的代码,在点击点之间画线(见下面的代码),最终结果是我可以用它绘制出一个平面图(我是一个建筑商) 我还试图找出如何删除单独绘制的线,而不必按下“重置”按钮,可能通过右键单击它们 不管怎么说,由于是如此新,这让我头痛不已。我一直在摆弄paper.js和jquery,现在已经好几天没有什么运气了 你们中有谁能给我指出一个正确的方向,给我一个我想要的教程/例子,或者给我一些关于在哪里寻求帮
var值={
fixLength:false,
固定角度:假,
秀圈:错,
showAngleLength:正确,
显示坐标:false
};
变量向量开始,向量,向量先前;
变量向量项、项目、dashedItems;
函数processVector(事件、拖动){
vector=event.point-vectorStart;
如果(矢量上一个){
if(values.fixLength&&values.fixAngle){
向量=向量先前;
}else if(value.fixLength){
vector.length=vector.length;
}else if(值。固定角度){
vector=vector.project(vectorPrevious);
}
}
牵引矢量(阻力);
}
函数drawVector(拖动){
若有(项目){
对于(变量i=0,l=items.length;i90
?textAngle=180+vector.angle:vector.angle;
//标签需要根据不同的位置移动不同的数量
//向量象限:
var away=(符号>=0?[1,4]:[2,3])。indexOf(向量象限)!=-1
? 8 : 0;
value=value | | vector.length;
var text=新点文本({
点:中间+远离中心。正常化(远离+长度大小),
内容:(前缀| |“”)+Math.floor(值*1000)/1000,
fillColor:'黑色',
理由:“中心”
});
文本。旋转(文本角度);
项目。推送(文本);
var values = {
fixLength: false,
fixAngle: false,
showCircle: false,
showAngleLength: true,
showCoordinates: false
};
var vectorStart, vector, vectorPrevious;
var vectorItem, items, dashedItems;
function processVector(event, drag) {
vector = event.point - vectorStart;
if (vectorPrevious) {
if (values.fixLength && values.fixAngle) {
vector = vectorPrevious;
} else if (values.fixLength) {
vector.length = vectorPrevious.length;
} else if (values.fixAngle) {
vector = vector.project(vectorPrevious);
}
}
drawVector(drag);
}
function drawVector(drag) {
if (items) {
for (var i = 0, l = items.length; i < l; i++) {
items[i].remove();
}
}
if (vectorItem)
vectorItem.remove();
items = [];
var arrowVector = vector.normalize(10);
var end = vectorStart + vector;
vectorItem = new Group([
new Path([vectorStart, end]),
new Path([
end + arrowVector.rotate(135),
end,
end + arrowVector.rotate(-135)
])
]);
vectorItem.strokeWidth = 0.75;
vectorItem.strokeColor = '#e4141b';
// Display:
dashedItems = [];
// Draw Circle
if (values.showCircle) {
dashedItems.push(new Path.Circle({
center: vectorStart,
radius: vector.length
}));
}
// Draw Labels
if (values.showAngleLength) {
drawAngle(vectorStart, vector, !drag);
if (!drag)
drawLength(vectorStart, end, vector.angle < 0 ? -1 : 1, true);
}
var quadrant = vector.quadrant;
if (values.showCoordinates && !drag) {
drawLength(vectorStart, vectorStart + [vector.x, 0],
[1, 3].indexOf(quadrant) != -1 ? -1 : 1, true, vector.x, 'x: ');
drawLength(vectorStart, vectorStart + [0, vector.y],
[1, 3].indexOf(quadrant) != -1 ? 1 : -1, true, vector.y, 'y: ');
}
for (var i = 0, l = dashedItems.length; i < l; i++) {
var item = dashedItems[i];
item.strokeColor = 'black';
item.dashArray = [1, 2];
items.push(item);
}
// Update palette
values.x = vector.x;
values.y = vector.y;
values.length = vector.length;
values.angle = vector.angle;
}
function drawAngle(center, vector, label) {
var radius = 25, threshold = 10;
if (vector.length < radius + threshold || Math.abs(vector.angle) < 15)
return;
var from = new Point(radius, 0);
var through = from.rotate(vector.angle / 2);
var to = from.rotate(vector.angle);
var end = center + to;
dashedItems.push(new Path.Line(center,
center + new Point(radius + threshold, 0)));
dashedItems.push(new Path.Arc(center + from, center + through, end));
var arrowVector = to.normalize(7.5).rotate(vector.angle < 0 ? -90 : 90);
dashedItems.push(new Path([
end + arrowVector.rotate(135),
end,
end + arrowVector.rotate(-135)
]));
if (label) {
// Angle Label
var text = new PointText(center
+ through.normalize(radius + 10) + new Point(0, 3));
text.content = Math.floor(vector.angle * 100) / 100 + '°';
text.fillColor = 'black';
items.push(text);
}
}
function drawLength(from, to, sign, label, value, prefix) {
var lengthSize = 5;
if ((to - from).length < lengthSize * 4)
return;
var vector = to - from;
var awayVector = vector.normalize(lengthSize).rotate(90 * sign);
var upVector = vector.normalize(lengthSize).rotate(45 * sign);
var downVector = upVector.rotate(-90 * sign);
var lengthVector = vector.normalize(
vector.length / 2 - lengthSize * Math.sqrt(2));
var line = new Path();
line.add(from + awayVector);
line.lineBy(upVector);
line.lineBy(lengthVector);
line.lineBy(upVector);
var middle = line.lastSegment.point;
line.lineBy(downVector);
line.lineBy(lengthVector);
line.lineBy(downVector);
dashedItems.push(line);
if (label) {
// Length Label
var textAngle = Math.abs(vector.angle) > 90
? textAngle = 180 + vector.angle : vector.angle;
// Label needs to move away by different amounts based on the
// vector's quadrant:
var away = (sign >= 0 ? [1, 4] : [2, 3]).indexOf(vector.quadrant) != -1
? 8 : 0;
value = value || vector.length;
var text = new PointText({
point: middle + awayVector.normalize(away + lengthSize),
content: (prefix || '') + Math.floor(value * 1000) / 1000,
fillColor: 'black',
justification: 'center'
});
text.rotate(textAngle);
items.push(text);
}
}
var dashItem;
function onMouseDown(event) {
var end = vectorStart + vector;
var create = false;
if (event.modifiers.shift && vectorItem) {
vectorStart = end;
create = true;
} else if (vector && (event.modifiers.option
|| end && end.getDistance(event.point) < 10)) {
create = false;
} else {
vectorStart = event.point;
}
if (create) {
dashItem = vectorItem;
vectorItem = null;
}
processVector(event, true);
// document.redraw();
}
function onMouseDrag(event) {
if (!event.modifiers.shift && values.fixLength && values.fixAngle)
vectorStart = event.point;
processVector(event, event.modifiers.shift);
}
function onMouseUp(event) {
processVector(event, false);
if (dashItem) {
dashItem.dashArray = [1, 2];
dashItem = null;
}
vectorPrevious = vector;
}