geometric-arc

I am writing an iPad app in which I am rendering XML objects that represent shapes into graphics on the screen. One of the objects I am trying to render is arcs. Essentially these arcs provide me with a bounding rectangle as well as a start and end angle. Given attributes: x y width height startAngle endAngle With these values I need to draw the arc (which is essentially part of an ellipse). I can not use the following: UIBezierPath *arc = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(x, y, width, height)]; [UIColor blackColor] setStroke]; [arc stroke]; because it draws a full ellipse.

I want to draw an arc using canvas using a gradient fill. How can achieve this? Hey I stole this from here: Draw an arc with a SweepGradient in Android but it works fine, I used a LinearGradient instead. Shader gradient = new SweepGradient (0,getMeasuredHeight()/2, Color.RED, Color.WHITE); lightRed.setShader(gradient); canvas.drawArc(rectf, -90, 360, false, lightRed); In my cause i I had to draw someone like this: Maybe you too. So, let's think! How does Sweep Gradient works? If you draw rect via this: private val colors = intArrayOf(ContextCompat.getColor(context, R.color.progress_from_color)

I'm trying to make a sort of pie-chart shape on a canvas element, however I can't seem to find any function that does this by itself. I only seem to be able to draw full circles and segments. Is there an easy way to do this? (See also: Wikipedia on circle terminology ) The following should work: context.moveTo(cx,cy); context.arc(cx,cy,radius,startangle,endangle); context.lineTo(cx,cy); context.stroke(); // or context.fill() with cx , cy being the center of the arc. 来源： https://stackoverflow.com/questions/6230363/how-to-draw-a-circle-sector-on-an-html5-canvas

Does anyone know how to define an animated arc / circle in SVG, such that the arc starts at 0 degrees and ends at 360 degrees? räph you can paint it "by hand" using path's lineto and calculate the position of the arc: <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" viewBox="0 0 1200 800" preserveAspectRatio="xMidYMid" style="width:100%; height:100%; position:absolute; top:0; left:0;" onload="drawCircle();"> <script> function drawCircle() { var i = 0; var circle = document.getElementById("arc"); var angle = 0; var radius = 100; window.timer =

I am trying to create an arc (variable number of degrees) that gradually goes from one color to another. From example from blue to red: This is my code: SweepGradient shader = new SweepGradient(center.x, center.y, resources.getColor(R.color.startColor),resources.getColor(R.color.endColor)); Paint paint = new Paint() paint.setStrokeWidth(1); paint.setStrokeCap(Paint.Cap.FILL); paint.setStyle(Paint.Style.FILL); paint.setShader(shader); canvas.drawArc(rectF, startAngle, sweepAngle, true, paint); But the result is the entire arc is painted with the same color. Edit: After more experimenting, I

I need to draw concentric arcs of various sizes using raphael.js. I tried to understand the code behind http://raphaeljs.com/polar-clock.html , which is very similar to what I want, but, whithout comments, it is quite difficult to fathom. Ideally, I would need a function that creates a path that is at a given distance from some center point, starts at some angle and ends at some other angle. genkilabs That answer is ok, but cant be animated. I ripped the important stuff out of polar-clock for you. Here is a red arc that animates growing. enjoy. // Custom Arc Attribute, position x&y, value