point

Hi I was wondering if there is any efficent way to calculating coordinates of point (which was moved distance d from it's original location). Let's say I have a point P(0.3,0.5) and I need to move that point random direction with distance d. So far I did it by random picking new x and y coordinates and I was checking if distance between old and new point equals d. I do realize that is't too eficient way to do that. How would You do it ?? Given a point (x1, y1) , we want to find a "random" point (x2, y2) at a distance d from it. Pick a random angle theta . Then: x2 = x1 + d * cos(theta) y2 = y1

I have an arrow image that I want to rotate from 0 to 180 degree (like the needle in a meter.) One point of the arrow is fixed in middle and at bottom of the screen and head of arrow should move. Length of arrow is fix (it is image). Also I have two buttons and I want arrow to turn left when button left is touched and turn right when right button is touched. What is the logic of this process? This is actually pretty simple if you are using a canvas to do your drawing(as you should in your case). Given that you know the coordinates for the point around which the image should rotate, you can do

I need to find out Y coordinate of specific point of bezier curve in canvas. Do you know, how to find it out? Thank you Using de Casteljau's algorithm you can find the coordinates x and y of a bezier curve for any t, the percentage or interpolation step. So a t of .1 would give you the x and y at 10% of the curve from the beginning. A t of .9 would be 90% from the beginning, and so on. In our cubic bezier we have p0 (point 0), cp0 (control point 0), cp1 (control point 1), and p1 (point 1). In the first step of the algorithm we draw a line connecting p0 and cp0, another line connecting cp0 and

Well, I'm currently trying to move a list of points using its center as reference with a desired offset. But I'm having problems. I have implemented the current function: public static IEnumerable<Point> Translate(this IEnumerable<Vector2> points, float offset, Vector2 pivot) { foreach (Vector2 v in points) { float magnitude = (v - pivot).magnitude; Vector2 n = (v - pivot).normalized; Vector2 _v = n * (magnitude + offset) + pivot; yield return new Point(_v); } } Note: Point class is an own implementation very similar to System.Drawing.Point . I calculate the normal (the direction between the

I am thinking how to add some marks to an image (I mean something like in google maps - marks for places). I have an image and if the user will clicked to this image, co I want on that place, where user clicked, add some other image. For example, if the user will click on 3 places in image, I would like to add on this places 3 my images... I know, how to get the directions, where the user clicked, but I don't know, how on that places add my image... And will be needed AJAX for it? So I would like to ask you about help, I will appropriate for each of hints. Thank you. There are several ways of