2
我有一个二次曲线,用于创建一个饼图。切片位于x和y轴上,中心点在(0,0)处。半径在半径X和半径Y处可变。此切片行进90度。将一个二次切片分成3个更小的切片HTML5 CANVAS JS
我需要将这个切片分成3个独立的切片(每个切片有30度角),并让它们匹配他们父母切片的任何曲线。
以下图片显示切片的可能示例。黑色圆圈调整片的大小/形状:
这里是我做的功能,但它只是工作不正常:
//globalPosX and globalPosY equal whatever position each of the two large black circles have repectively.
var canvas = document.getElementById('CV_slices');
var context = canvas.getContext('2d');
var cenX = canvas.width/2;
var cenY = canvas.height/2;
var blackDotX = globalPosX - cenX;
var blackDotY = cenY - globalPosY;
var endX;
var endY;
var controlX;
var controlY;
//set first slice
var startCoOrds = {
x: cenX ,
y: globalPosY
};
for (i=1; i < 4; i++) {
//make end(x,y) of previous slice the start(x,y) for the next slice.
endX = startCoOrds.x - (blackDotX*Math.sin(30));
endY = startCoOrds.y + (blackDotY*Math.cos(30));
//set position of control point using position of start/end positions (at the moment only adjustibng using +10 -10 at end)
controlX = ((endX - startCoOrds.x) /2) + (startCoOrds.x) + 10;
controlY = ((endY - startCoOrds.y)/2) + (startCoOrds.y) - 10;
// draw slice
context.save();
context.beginPath();
context.moveTo(cenX, cenY);
context.lineTo(startCoOrds.x, startCoOrds.y);
context.quadraticCurveTo(controlX, controlY, endX, endY);
context.lineTo(cenX, cenY);
//make end(x,y) of previous slice the start(x,y) for the next slice
startCoOrds.x = endX;
startCoOrds.y = endY;
context.closePath();
context.globalAlpha = 0.1;
context.fillStyle = "#333333";
context.fill();
context.lineWidth = 2;
context.strokeStyle = "#ffffff";
context.stroke();
context.restore();
}
@Feeny我已经运行这个,但我仍然不清楚 - 对不起。 'globalPosX和globalPosY等于两个黑色大圆圈中的每一个都具有什么意思'是什么意思。黑圈在哪里?我知道图像丢失了。我已经投票给你了。你可以把它们放在现在吗? – 2012-01-12 13:36:09
@CrabBucket我需要声望10才能添加图片 – Feeney 2012-01-12 14:48:03
@Feeny您现在应该有足够的代表; – 2012-01-12 15:32:43