Perspective Projection MATRIX ?

Perspective Projection MATRIX ?

Post by Daniel Leontie » Sun, 01 Sep 2002 14:44:25



Hello all, I'm a new to algebra, but am very interested in learning.
So I was wondering if anyone can provide a link to a tutorial that
would explain all things about perspective transformation matrix.

I have been learning all the rotation and scaling and translations.
but am not able to write my own functions for perspective transformations.
I know I can use GL_PROJECTION_MATRIX, but I am more interested in
the actual implementation of the whole matrix staff. For example if I want
to
write some program with out using OpenGL just to solidify my skills in
algebra and staff.

Thank you for you time.

Daniel.

 
 
 

Perspective Projection MATRIX ?

Post by Deluxe Rever » Sun, 01 Sep 2002 15:36:31


An admirable goal - I did the same thing many moons ago ;) The OpenGL Red
Book is an excellent source, it does a good job of describing projection,
and even shows you the exact contents of the perspective and othographic
matrices, as well as the matrices for translation, scaling, and rotation.
Plus, it's an indispensable resource for OpenGL-specific info. With this,
you'll be able to write your own Ortho, Frustum, Perspective, and LookAt
functions, plus variations that may fit your needs even better than those
provided by GL or GLU.

Check comp.graphics.opengl for a link to an on-line copy of the book.

Danny


Quote:> Hello all, I'm a new to algebra, but am very interested in learning.
> So I was wondering if anyone can provide a link to a tutorial that
> would explain all things about perspective transformation matrix.

> I have been learning all the rotation and scaling and translations.
> but am not able to write my own functions for perspective transformations.
> I know I can use GL_PROJECTION_MATRIX, but I am more interested in
> the actual implementation of the whole matrix staff. For example if I want
> to
> write some program with out using OpenGL just to solidify my skills in
> algebra and staff.

> Thank you for you time.

> Daniel.


 
 
 

Perspective Projection MATRIX ?

Post by Just d' FAQ » Mon, 02 Sep 2002 08:58:42


On Sat, 31 Aug 2002 05:44:25 GMT, "Daniel Leontiev"

>Hello all, I'm a new to algebra, but am very interested in learning.
>So I was wondering if anyone can provide a link to a tutorial that
>would explain all things about perspective transformation matrix.
>[snip]

You can start with the limited discussion in the FAQ
  "Subject 5.14: How do I perform basic viewing in 3D?"

That's only an overview, not "all things". :)

One thing to keep in mind is that a matrix cannot give perspective
effects unless your points are in homogeneous coordinates. If you only
have (x,y,z) it won't work. If you have (x:y:z:w) you will treat that
as (x/w,y/w) for 2D display, and that will work.

 
 
 

Perspective Projection MATRIX ?

Post by Just d' FAQ » Mon, 02 Sep 2002 11:23:15




Quote:>That's only an overview, not "all things". :)

Thought I'd add a classic discussion of viewing:
  <ftp://ftp.alvyray.com/Acrobat/View84.pdf>