Results 1 to 2 of 2

Thread: Default Ortho volume

  1. #1
    Junior Member Newbie
    Join Date
    Aug 2004
    Location
    india
    Posts
    19

    Default Ortho volume

    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
    Sophia.

  2. #2
    Senior Member Frequent Contributor
    Join Date
    Apr 2004
    Posts
    990

    Re: Default Ortho volume

    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

Similar Threads

  1. Replies: 2
    Last Post: 06-06-2015, 07:35 AM
  2. Default value for uniform?
    By Leadwerks in forum OpenGL: GLSL
    Replies: 12
    Last Post: 08-08-2008, 02:11 AM
  3. Perspective/Ortho Projection for Volume Rendering
    By iris_raj in forum OpenGL: Advanced Coding
    Replies: 4
    Last Post: 11-06-2007, 04:54 AM
  4. ortho + perspective + ortho
    By mithun_daa in forum OpenGL: Basic Coding
    Replies: 6
    Last Post: 06-09-2004, 07:54 AM
  5. shadow volume (mesh inside shadow volume of another)
    By greg2 in forum OpenGL: Advanced Coding
    Replies: 4
    Last Post: 10-23-2003, 11:49 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Proudly hosted by Digital Ocean