I thought that this would be something I could do with 3d stroke but I may have been wrong as I cant seem to control the strokes shape. Im trying to track across a map drawing a 3d stroke from point 'a' which rises up towards camera, I follow it across the map until it descends to point 'b'.
Im fine with getting the line to draw but I cant work out how to get the curvature of the line Im after where the apex of the curve is close to the camera.
Can anyone give me some pointers or tell me it cant be done?
You should try to draw your path curved instead of drawing straight. Once you've done that, try to position the stroke perpendicular to your map using the 3dstroke transform>rotation system. Put 3d stroke camera settings on "comp camera". You just have to animate your camera after that!
You need to draw your mask shape as a parabolic curve or circle and then rotate it in place using the internal transformation controls. There is no need to exaggerate since you can also use the tapering to thicken up your stroke where it's closer to the camera. As an addition, you should think of having your stroke cast a shadow on your map. It can be completely fake but should reflect the shape of the curve. It will greatly help you sell the illusion.