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Only Sophoo...
09-09-2004, 10:31 PM
I have a fundamental question.
In the initial state - We have the modelview matrix set to identity.
When we draw any objects on it , we can draw objects, with z as zero. Objects with non-zero z are not drawn.
What are teh limits for x and y ?
What is the default or initial Orhto volume ?

regards
- S

-NiCo-
09-09-2004, 11:20 PM
Originally posted by Sweety:
When we draw any objects on it , we can draw objects, with z as zero. Objects with non-zero z are not drawn.
In the initial state both the projection and the modelview matrix are set to identity.
Since the OpenGL viewing volume is specified between -1 and 1 for the x, y and z-axis, everything that is inside this volume after modelviewmatrix conversion and projection is drawn.

So with the initial states for both modelview and projection you can draw every vertex with the 3 components between -1 and 1, and not only with z=0.

Greetz,

Nico