1 reply to this topic

[Nouman]

Hi, I am trying to write a map renderer that could display maps in perspective or bird's eye view mode using 2d road map data, it is like you are viewing from an inclined elevated point and the map is laid on a horizontal plane or in other words it is the view of the road netwrok lying ahead of you when you are driving a car (bit elevated). The problem is that I want to run this application on mobile devices without accelerated 3d graphics so I can't use 3d graphics, virtual cameras and expensive transformations. I need to find a way to tranform the 2d road map data in to perspective view. I want to eventually use it for a navigation application.

Thanks in advance

nouman.hanif

[patdunlavey]

It's been a number of years since I played with vector rendering so I may have this wrong, but I believe this is quite simple and not more computationally intensive than an orthogonal transform is. Though you are thinking of this as a perspective view in 3D, I think that the flat-perspective effect can be accomplished using a 2D transform, or perhaps a slightly "enhanced" 2D transform (i.e. a 3D transformation matrix where you ignore a number of the components).