quote:

---

Original post by AdmiralBinary
Email Einstein about his Theory of Relativity. The bottom line is, that in 3d space, there is NO absolute size. "Size" is always relative to one thing or another. You''re standing in a matrix-style white space. You are looking directly at a giant with no other objects around. Now how can you tell that it''s a giant unless you have something to compare it to (an ant, for example lol) Did that make sense?

---

This is a real good explanation of the real world and how OpenGL represents its "space."

For example, if you made a distance of 1.0f in OpenGL to be the size of an ant, then the giant had better be 10000.0f tall.

Does that complete it any better?

Still don''t completely get it... I do understand the theory of relativity. But each coordinate has to be equally spaced. Like the distance between (1,0,0) and (2,0,0) is fixed and will be the same as the distance between (3,0,0) and (4,0,0).. if so what is the distance? It only comes into question when the Z-axis is used... plz correct me if I''m wrong
Plz help me out with the code too

The distance between (1, 0, 0) and (2, 0, 0) is always the same as the distance between (3, 0, 0) and (4, 0, 0) in WORLDSPACE coordinates. If you project these to the viewport, you get VIEWPORT coordinates, which is a completely different thing. In viewport coordinates, the distance is not guaranteed to be the same.

Another way to think about it.

You are standing at a fence, looking at it. The actual distance between each pole in the fence is the same (this is worldspace). But from your point of view, the distance between each pole is less and less the futher away they are (this is the viewport).

The distance between 0 and 1 is originally half your screen. But this changes as soon as you change either matrix.

Tks a lot, that cleared it up for me. Another doubt : is it possible to define a polygon with height 0.01f (y=0.01)? I tried but the program just gives me a polygon with height 0.1f.

If you mean "what units do GLunits equal" then the answer is "whatever you want them to". As long as everything _appears_ proportionately correct (sp?).

Alex Broadwin
A-Tronic Software & Design
-----
"if you fail in life, you were destined to fail. If you suceed in life, call me."
"The answer is out there."
"Please help, I''m using Windows!"

OpenGL does accept values under 0.1f. How do you know that it is treating the 0.01 as 0.1? It''s very possible that due to your current projection that it''s difficult to notice the difference.

Because whenever I enter a value below 0.1f the polygon looks the same as if it were 0.1f... I even tried 0.000000000001f and still the same results.