After a long struggle i found the root cause of my issue right from the scratch. Thanks for the tool which helped me to generate the coordinates and also the blog which showed me the exact sample for my need. Finally my code is as follows: public class DrawView extends View { Paint paint; Path … Read more
I have similar problem and I have found “An algorithm for automatically fitting digitized curves” from Graphics Gems (1990) about Bezier curve fitting. Additionally to that I have found source code for that article. Unfortunately it is written in C which I don’t know very well. Also, the algorithm is quite hard to understand (at … Read more
Intersection of Bezier curves is done by the (very cool) Asymptote vector graphics language: look for intersect() here. Although they don’t explain the algorithm they actually use there, except to say that it’s from p. 137 of “The Metafont Book”, it appears that the key to it is two important properties of Bezier curves (which … Read more
You can reduce the number of points using the Ramer–Douglas–Peucker algorithm there is a C# implementation here. I gave this a try using WPFs PolyQuadraticBezierSegment and it showed a small amount of improvement depending on the tolerance. After a bit of searching sources (1,2) seem to indicate that using the curve fitting algorithm from Graphic … Read more
I hope you found my math paper useful Quadratic bezier offsetting with selective subdivision https://microbians.com/mathcode
Let P0, P1, P2 be the control points, and Pc be your fixed point you want the curve to pass through. Then the Bezier curve is defined by P(t) = P0*t^2 + P1*2*t*(1-t) + P2*(1-t)^2 …where t goes from zero to 1. There are an infinite number of answers to your question, since it might … Read more
Maybe someone is searching for an answer, like me for two days now: // Draw a path and hide it: var root = paper.path(‘M0 50L30 50Q100 100 50 50’).hide(); var length = root.getTotalLength(); // Setup your animation (in my case jQuery): element.animate({ ‘to’: 1 }, { duration: 500, step: function(pos, fx) { var offset = … Read more
A Demo: http://jsfiddle.net/m1erickson/4fX5D/ It’s fairly easy to create a gradient that changes along the path: It’s more difficult to create a gradient that changes across the path: To create a gradient across the path you draw many gradient lines tangent to the path: If you draw enough tangent lines then the eye sees the curve … Read more
The tangent of a curve is simply its derivative. The parametric equation that Michal uses: P(t) = (1 – t)^3 * P0 + 3t(1-t)^2 * P1 + 3t^2 (1-t) * P2 + t^3 * P3 should have a derivative of dP(t) / dt = -3(1-t)^2 * P0 + 3(1-t)^2 * P1 – 6t(1-t) * P1 … Read more
I just implemented something similar in a project I am working on. My solution was to use a Catmull-Rom spline instead of using Bezier splines. These provide a very smooth curve THROUGH a set a points rather then a bezier spline ‘around’ points. // Based on code from Erica Sadun #import “UIBezierPath+Smoothing.h” void getPointsFromBezier(void *info, … Read more