Archived:How to implement a Relative Map using GPS in Flash Lite 3.0
A Relative Map is known as a in-scale map according with the distance in the real world. For example: You retrieve your current coordinates by GPS and, after that, move 100 meters ahead and then you want to know the pixel distance on the mobile phone's screen regarding with the scale you chose. Would be better show where you are in the Relative Map in agreement with your moviments. Well, I'll explain step-by-step how to do it from, implement the geometric functions to calculate the relation between the real world distance and the relative distance to retrieve asynchronously GPS location informations.
1.1 - For starts you must create a new mobile project and select Flash Lite 3.0 and ActionScript 2.0 as player version and ActionScript version, respectively.
1.2 - Insert 4 (four) KeyFrames as in the order shown below:
Relative Map Scheme
Let's understand what 'area_limit' is; It is the maximum value in meters which you can move vertically or horizontally. As the name says 'scale' represents the scale between the drawn rectangle height on the frame and the 'area_limit' double. This value means that every walked meter M in the real world there are P 'walked' pixels on the mobile screen. So, we had found the 'd_x' and 'd_y' meters distances multiply each one of them for the 'scale' to acquire the horizontal and vertical disntances in pixels. For more details see the scheme shown below: