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View Full Version : how to "stop drawing with a picture" ?



nullspace
11-26-2001, 06:45 AM
Hello, firt of all i'm french so...don't be careful about the mistakes !!
Well, for instance i draw a triangle that is filled with a texture, next, when i want to draw lines, they are also filled with the texture !!
So i would want to find a function that disable the "texture fill"

yes, last thing, i don't know if it better to use Lookat or the rotation...or if it is the same (i speak about the speed...) in a game like a "quake-like".
Thank you !

Eric
11-26-2001, 07:25 AM
In order to disable the texture, you have to use:




glDisable(GL_TEXTURE_2D);


Of course that's if you had a 2D-texture activated (which I suppose you had to fill your triangle....).

The same kind of code is used with 1D or 3D textures:




glDisable(GL_TEXTURE_1D);
glDisable(GL_TEXTURE_3D);


Il est pas si mauvais que ca ton anglais ! http://www.opengl.org/discussion_boards/ubb/rolleyes.gif

Regards.

Eric

Eric
11-26-2001, 07:27 AM
Forgot to answer the second part of your question !

Typically, if you decide not to use gluLookAt, you'll end up building your own myLookAt function that will do exactly the same thing... Even worse: some people say they do not want to use GLU anymore so they stop using gluLookAt and rip the implementation of the function from MESA !

It's up to you: if the only function you want to use from GLU is gluLookAt then you may as well implement your own...

Seeing that this function is typically used once a frame (OK, can be more if you are generating cube maps !), I don't think there will be any speed difference...

Regards.

Eric

nullspace
11-26-2001, 08:42 AM
Thank you for the answers.
It is alright except that it draw something white and don't pay attention at glColor3d.

My part of code is :

glBegin(GL_LINES);
glColor3d(1,1,0);
glVertex3f(tempn,0.5f,(float)h/20-0.5);
glEnd();

NB for éric in french: eh eh je vois qu'on maitrise bien le french !! T'es pas de nationalitée française?

chowe6685
11-26-2001, 05:21 PM
if you are using lighting glColor3f(...) won't work you need to either use
glEnable(GL_COLOR_MATERIAL);
or
glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, x);
x is a pointer to an array containing the three values you want for a color, for a simple project GL_COLOR_MATERIAL is easier, but I would recommend you learn about glMaterial