I appreciate the response.

The markers don't need to be interactive, but they need to be added
from a
realtime JSON feed... basically I need to create a timer to reload the
JSON
feed I guess...



On Feb 14, 5:18 am, richardolsson <[email protected]> wrote:
> If the points don't need to be interactive, it is just as easy and
> definitely more optimal performance-wise to just draw your dots onto
> the bitmap data that you use for the material. That way you won't need
> to add any extra geometry OR any extra display objects for each dot
> marker, essentially making 0 dots and 1 gazillion dots using the same
> (tiny) amount of resources.
>
> If you decide to go with this approach, you won't even have to do any
> 3D math, since the dots are only drawn onto a 2D map. You do need to
> convert your geographic coordinates to a point in the map though. For
> the X axis, just start at the zero-meridian (Greenwich, London) and
> calculate the x position from the longitude, using a scale factor that
> you will need to calculate from the size of your map (remember, the
> entire map is 360 degrees wide, so if it's 2000px, each degree is
> ~5.56px.)
>
> For the Y axis, you'll need to read up on Mercator Projection (http://
> en.wikipedia.org/wiki/Mercator_projection) which is the projection
> that I'm assuming that you're using. Use the function described there
> to calculate a point on a map from a given latitude, and this time
> start at the equator.
>
> So basically it's a linear function for the longitudes (really simple
> math) and a non-linear one for the latitudes (just copy off of the
> wikipedia article.)
>
> Cheers
>
> On Feb 13, 4:53 pm, Shaun <[email protected]> wrote:
>
> > I've read over all of the posts on here and I'm having problems
> > getting this to work.
>
> > I'm using Away3D in Flash CS4
>
> > What I have:
> > 1. A sphere that is textured via a BitmapMaterial
> > 2. A JSON feed that has latitude/longitude
>
> > What I'd like to do is take the lat/long and use it to plot points on
> > the sphere.  I figure I can do it one of two ways - either use Away3D
> > to add points to the sphere, or I can change my BitmapMaterial to a
> > MovieMaterial and plot points on it (add children MovieClips to the
> > MovieMaterial).
>
> > So - my question is two fold:
>
> > 1. Which is the better approach (better = better performance for lots
> > of points)
> > 2. How do I go about implementing the better approach?
>
> > Thanks

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