Try the following. Write a class which derives from the Overlay class and override the onTap() method. Then you can add your overlay to the your MapView. A GeoPoint object, which represents the position of you tap, is passed to the onTap() method when you tab somewhere on the map.
The projection you use is going to change everything, but this will work assuming a Mercator projection: <html> <head> <script language=”Javascript”> var dot_size = 3; var longitude_shift = 55; // number of pixels your map’s prime meridian is off-center. var x_pos = 54; var y_pos = 19; var map_width = 430; var map_height = 332; … Read more
I have figured it out, thanks for the feedback Tanmay. I noticed that the y-offset was incorrect for n – cols and should be row – half instead. Below is the most comprehensive and compact code I could obtain. Although it is preferred to enter an odd integer for the size, you could enter a … Read more
I guess it should not be difficult to find the spherical polar coordinates from x,y,z (3d-coordinate system). r is always constant if it’s on surface. (90 – θ) your latitude (negative means it’s on the bottom) as it’s measured from top. φ is your longitude. (but not quite sure about longitude system) Also check this … Read more
A very simple example of a swing component to draw lines. It keeps internally a list with the lines that have been added with the method addLine. Each time a new line is added, repaint is invoked to inform the graphical subsytem that a new paint is required. The class also includes some example of … Read more
You want the arctangent: dy = ey – cy dx = ex – cx theta = arctan(dy/dx) theta *= 180/pi // rads to degs Erm, note that the above is obviously not compiling Javascript code. You’ll have to look through documentation for the arctangent function. Edit: Using Math.atan2(y,x) will handle all of the special cases … Read more
You need to compute a unit vector that’s perpendicular to the line segment. Avoid computing the slope because that can lead to divide by zero errors. dx = x1-x2 dy = y1-y2 dist = sqrt(dx*dx + dy*dy) dx /= dist dy /= dist x3 = x1 + (N/2)*dy y3 = y1 – (N/2)*dx x4 = … Read more
Perhaps the following illustration showing the relationship between the various spaces will help: Depending if you’re using the fixed-function pipeline (you are if you call glMatrixMode(), for example), or using shaders, the operations are identical – it’s just a matter of whether you code them directly in a shader, or the OpenGL pipeline aids in … Read more
If you keep a copy of the AffineTransform you use when you paint the image, you can use AffineTransform.inverseTransform(Point2D ptSrc, Point2D ptDst) to transform a device space coordinate back to user space Edit: If you capture the current transform of the Graphics2D while painting, beware of the Graphics2D being re-used for multiple lightweight children of … Read more