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answer
03-08-2004, 04:41 PM
what is opengl mesured in. what I mean by this is that when drawing on the screen I am not giving parameters in pixels but something else. What unit of mesurement does the glVertex2f() function take? and 3f?

chowe6685
03-08-2004, 06:45 PM
none, opengl doesn't have units. The size of the screen is defined by the viewport and the various matrices, look at glViewport and the various projection matrices for details

nexusone
03-09-2004, 09:27 AM
OpenGL does not have a measurment per say, lines are drawn as vector.

In one program 0.0 1.0 in openGL units may draw the line across the whole screen, while in another program these values will give you maybe a dot. There all relative to your view port and projection settings.


glVertext?? Where the number show how many values it expects to receive, and the letter is the variable type, f=float, i=int, etc.

glVertex2f(x,y) where x/y is a float value
glVertext3f(x,y,z)


Originally posted by answer:
what is opengl mesured in. what I mean by this is that when drawing on the screen I am not giving parameters in pixels but something else. What unit of mesurement does the glVertex2f() function take? and 3f?