angle

问题 I need rotate arrow with Jquery-rotate, but i dont know cursor's angle :( I try calculate it, but script not work. I want result like this http://www.lonhosford.com/content/html5/canvas/rotate_to_mouse.html <script type="text/javascript"> //<![CDATA[ $(document).ready(function(){ function diff(x, y) { var a = (x * Math.PI / 180) - Math.PI; var b = (y * Math.PI / 180) - Math.PI; return Math.atan2(Math.sin(b - a), Math.cos(b - a)) * (180 / Math.PI); } $('body').mousemove(function(e){ var x = e

问题 I have two lines specified by two points with x and y coordinate each. The first point (where the lines begin) is equal meaning that I have 3 points A, B and C where one line is from A to B and the other one from A to C. I would then want to calculate the angle between the two lines starting at the right side of the first line . The result needn't be accurate I actually only need to know if this angle is greater or less than 180° (π rad). Thanks for any help - you needn't write any code,

问题 I've scrounged the web in search of a good example or someone trying to attempt the same thing, but so far I haven't had much luck. I am trying to get my Devices rotation angle (If you can imagine) starting at 180° (Flat). As the user tilts the device left and right, the angle adjusts accordingly. And as it rotates I want to simply update a TextView. I'm just lost as to what this evolves, some people suggest a gyroscope, accelerometer, even a magnometer, or a combination. I've gotten a few

问题 i used image.HoughLine to find line in my image. i want to know the angle of each line. so i tried : double deltaY = line.P2.Y - line.P1.Y; double deltaX = line.P2.X - line.P1.X; double angle; if (deltaX != 0) angle = Math.Atan2(deltaY, deltaX); else angle = 90; but , it returns 0 and -1 , while the lines in image at least have 15 degree . ( i rotated the image myself ). what's wrong? and what is Direction in LineSegment2D class, could it help ? 回答1: I Found myself the solution. you know what

问题 On my way to finding a CSS solution to have an evenly colored element with angled beginning to avoid images I stumbled across this simple example: http://dabblet.com/gist/1780333 . This one is working fine, even in IE of the latest, only Safari is reversing it completely, putting it to the end instead of the beginning AND turning the angle partly, at least in my live site it's not consistent. I have, of course, the same values for all browser versions. Anybody an idea why it is so and what

问题 I have two button(the arrows), when they are pressed everything works as expected. What is not working is moving the ground with the mouse(hover the mouse over the wheel to see), it keeps jumping back to previous value(shown by the numbers on the plane). How to translate a plane by rotating a circle with the mouse? const plane = $('#plane') const planeX = plane.offset().left const wheel = $('.wheel>div') const radius = wheel.width() / 2 let degrees = 0 // buttons let interval $(document).on(

问题 For a project we're making a topdown-view game. Characters can turn and walk in all directions, and are represented with a point and an angle. The angle is calculated as the angle between the current facing direction and to the top of the program, and can be 0-359. I have the following code for the movement: public void moveForward() { position.x = position.x + (int) (Math.sin(Math.toRadians(angle)) * speed); position.y = position.y + (int) (Math.cos(Math.toRadians(angle)) * speed); } public

问题 I have a Pong-360 game in which the arc shaped paddles deflect a ball that should stay within the circular boundary. If the ball does not encounter a paddle when it gets to the boundary, it continues out of bounds and the player to last hit the ball scores. The problem I am having is returning the ball in the correct direction upon impact with a paddle. If the ball contacts a certain half of the paddle it should bounce in that direction but in any case should be returned to the opposite side

问题 Im making a game in XNA. I have enemies and player. The enemies should turn gradually towards the player. They should work out whether they need to turn clockwise or anticlockwise, whichever is shorter. I got the angle the enemy is currently facing and the angle it should be facing (the angle of the line between the enemy and the player) as radians by using Atan2. I get some weird behavior though. Lets say in the scenario below. the enemy might turn all the way around in the wrong direction.

问题 What is the fastest way to calculate angle between a line and the x-axis? I need to define a function, which is Injective at the PI:2PI interval (I have to angle between point which is the uppermost point and any point below). PointType * top = UPPERMOST_POINT; PointType * targ = TARGET_POINT; double targetVectorX = targ->x - top->x; double targetVectorY = targ->y - top->y; first try //#1 double magnitudeTarVec = sqrt(targetVectorX*targetVectorX + targetVectorY*targetVectorY); angle = tarX /