Zoom By Region

[kal_mans]

I am using Opengl on Linux...
am using the QT Designer...
i wanna zoom by region..so i need to know how to implement that rectangle which usually we see while zooming by region which actually showz the region which is selected..
Am waiting for ur reply,
Kalpesh

[chief]

look at http://www.codeproject.com/opengl/opengl_zooming.asp

[roffe]

Simple zoom:

- Setup viewport/scissor/aspect ratio for region selected.
- Point camera towards selection and apply appropriate scaling on x and y axis to zoom in on the 2d projected image.