具有三個手柄的貝塞爾曲線錯位了控制點
[英]Bezier curve with three handles misplaces the control points
問題描述
我設法用拉斐爾圖書館的例子繪制了四條不同的曲線。 現在，我想創建一個包含多個手柄的曲線。 如何在此示例中添加更多句柄。
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Bezier curve</title>
<style>
#holder {
height: 100%;
left: 100%;
margin: -100% 0 0 -100%;
position: absolute;
top: 100%;
width: 100%;
}
</style>
<script src='jquery.js'></script>
<script src="raphael.js"></script>
<script>
$('document').ready(function () {
var r = Raphael("holder", window.innerWidth, window.innerHeight)
function curve(x, y, ax, ay, bx, by, zx, zy, color) {
var path = [["M", x, y], ["C", ax, ay, bx, by, zx, zy]],
path2 = [["M", x, y], ["L", ax, ay], ["M", bx, by], ["L", zx, zy]],
curve = r.path(path).attr({stroke: color || Raphael.getColor(), "stroke-width": 4, "stroke-linecap": "round"}),
controls = r.set(
r.path(path2).attr({stroke: "#ccc", "stroke-dasharray": ". ","stroke-width":2}),
r.circle(x, y, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(ax, ay, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(bx, by, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(zx, zy, 5).attr({fill: "#9F2200", stroke: "none"})
);
controls[1].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[0][1] = X;
path[0][2] = Y;
path2[0][2] = X;
path2[0][2] = Y;
controls[2].update(x, y);
};
controls[2].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][3] = X;
path[1][2] = Y;
path2[1][4] = X;
path2[1][2] = Y;
curve.attr({path: path});
controls[0].attr({path: path2});
};
controls[3].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][3] = X;
path[1][4] = Y;
path2[2][5] = X;
path2[2][2] = Y;
curve.attr({path: path});
controls[0].attr({path: path2});
};
controls[4].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][5] = X;
path[1][6] = Y;
path2[3][6] = X;
path2[3][2] = Y;
controls[3].update(x, y);
};
controls.drag(move, up);
}
function move(dx, dy) {
this.update(dx - (this.dx || 0), dy - (this.dy || 0));
console.log(this.dx,this.dy);
this.dx = dx;
this.dy = dy;
}
function up() {
this.dx = this.dy = 0;
}
curve(70, 100, 110, 100, 130, 200, 170, 200, "hsb(0, 0, 0)");
curve(800, 200, 800, 100, 600, 100, 600, 200, "hsb(0, 0, 0)"); // xp1,yp1, , , , , xp2,yp2 where (xp1,xp2) & (xp2,yp2) are two end points
curve(500, 200,500, 300, 300, 300, 300, 200, "hsb(0, 0, 0)"); // xp1,yp1, , , , , xp2,yp2 where (xp1,xp2) & (xp2,yp2) are two end points
curve(920, 100,880, 100, 1020, 200, 980, 200, "hsb(0, 0, 0)");
});
</script>
</head>
<body>
<div id="holder"></div>
</body>
</html>
</body>
演示的鏈接是http://jsfiddle.net/insane36/fddGJ/1/
我編輯了代碼並再次嘗試放置多個句柄以顯示中間的主句柄但有一些問題，我不知道我是否理解它背后的概念。 我想用下圖創建一個帶手柄的圖形，並能夠操縱手柄;
三個句柄的代碼是;
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Bezier curve</title>
<style>
#holder {
height: 100%;
left: 100%;
margin: -100% 0 0 -100%;
position: absolute;
top: 100%;
width: 100%;
}
</style>
<script src="raphael.js"></script>
<script>
window.onload=function () {
var r = Raphael("holder", window.innerWidth, window.innerHeight)
function curve(x1, y1, cx1, cy1, cx2, cy2, x2, y2,cx3,cy3,cx4,cy4, color) { //zx --x1
var path = [["M", x1, y1], ["C", cx1, cy1, cx2, cy2, x2, y2,"S",cx3,cy3,cx4,cy4]],
path2 = [["M", x1, y1], ["L", cx1, cy1], ["M", cx2, cy2], ["L", x2, y2],["M", cx3,cy3],['L',cx4,cy4]],
curve = r.path(path).attr({stroke: color || Raphael.getColor(), "stroke-width": 4, "stroke-linecap": "round"}),
controls = r.set(
r.path(path2).attr({stroke: "#ccc", "stroke-dasharray": ". ","stroke-width":2}),
r.circle(x1, y1, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(cx1, cy1, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(cx2, cy2, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(x2, y2, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(cx3, cy3, 5).attr({fill: "#9F2200", stroke: "none"}),
r.circle(cx4, cy4, 5).attr({fill: "#9F2200", stroke: "none"})
);
controls[1].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[0][9] = X;
path[0][2] = Y;
path2[0][10] = X;
path2[0][2] = Y;
controls[2].update(x, y);
};
controls[2].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][11] = X;
path[1][2] = Y;
path2[1][12] = X;
path2[1][2] = Y;
curve.attr({path: path});
controls[0].attr({path: path2});
};
controls[3].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][3] = X;
path[1][4] = Y;
path2[2][13] = X;
path2[2][2] = Y;
curve.attr({path: path});
controls[0].attr({path: path2});
};
controls[4].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][5] = X;
path[1][6] = Y;
path2[3][14] = X;
path2[3][2] = Y;
controls[3].update(x, y);
};
controls[5].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][8] = X;
path[1][9] = Y;
path2[4][15] = X;
path2[4][2] = Y;
controls[4].update(x, y);
};
controls[6].update = function (x, y) {
var X = this.attr("cx") + x,
Y = this.attr("cy") + y;
this.attr({cx: X, cy: Y});
path[1][10] = X;
path[1][11] = Y;
path2[5][16] = X;
path2[5][2] = Y;
controls[5].update(x, y);
};
controls.drag(move, up);
}
function move(dx, dy) {
this.update(dx - (this.dx || 0), dy - (this.dy || 0));
console.log(this.dx,this.dy);
this.dx = dx;
this.dy = dy;
}
function up() {
this.dx = this.dy = 0;
}
curve(10, 80, 40, 10, 65,10,150,150,95, 80, 180,180, "hsb(0, 0, 0)");
};
</script>
</head>
<body>
<div id="holder"></div>
</body>
</html>
</body>
</html>
我想我已經錯過了，沒有正確安排控制點和值
1 個解決方案
解決方案1
1 已采納 2011-12-09 17:02:57
看看這個小提琴 - 我想我已經做到了你正在尋找的東西。 （ 編輯：修復這個小提琴，這樣你就不必在curve()構造函數中指定反射的控制點）
我認為關鍵是曲線中間點的第二個控制點只是第一個控制點的反映（根據SVG文檔 ），所以你必須對那些控制的'假'進行排序。 （你的代碼確實有一些問題，你的update（）函數試圖更新不存在的數組值，比如path[1][6] = Y; ... path[1]只有三個元素）
如果你希望兩個控制點獨立運行（這樣曲線在這一點上不一定是平滑的），我認為你必須從你的路徑中刪除“S”，並改變一些代碼（這里是一個像那個 ）
如果您希望允許兩個控制點從該點移動不同的距離，但保持曲線平滑點，我認為您必須手動執行此操作。 您可以從第二個示例開始，但是您必須以編程方式將移動控制點的角度反映到相對的控制點，同時允許從相對控制點到曲線上的點的距離保持固定。
如何計算貝塞爾曲線上的控制點？
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