Determining Valid RasterPos Values

Hello -
I am having trouble determining what raster position values are valid when I am using the scissor test and numerous transformations. I have been using the commands:

GLboolean valid_position;
glGetBooleanv (GL_CURRENT_RASTER_POSITION_VALID, &valid_position);

and they always return false. This is useful for debugging, but it doesn’t actually help me solve my problem. I was wondering if instead there is a way to run a query for the range of valid values? If anybody has any thoughts concerning how I might go about this, I would really appreciate it. Thanks!

-lost hope

to determine