Yeah I understand that. Just so we're clear; my suggestion was to use
BitmapData.draw() to draw the markers onto the material bitmap, not to
draw them in using Photoshop or anything like that. :)

Cheers
/R


On Feb 15, 10:29 pm, Shaun <[email protected]> wrote:
> 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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