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Ledivin
12-04-2010, 01:24 PM
How can I go about this? I've done lots of reading, and I just can't find anything regarding it... I'm sure it's just something simple, but it's a surprisingly hard subject to search for.

Thanks in advance!

EDIT: I guess it's important to say I'm using PyOpenGL, though it shouldn't make a large difference.

I've also been having some trouble regarding multiple lights, eg:



glEnable(GL_LIGHT0)
glLight(GL_LIGHT0, GL_POSITION, (0, 1, 1, 0))
glEnable(GL_LIGHT1)
glLight(GL_LIGHT1, GL_POSITION, (0, 1, 1, 0))

glLightfv(GL_LIGHT0, GL_POSITION, (0, 1.5, 1, 0))
glLightfv(GL_LIGHT1, GL_POSITION, (0, 1.5, 1, 0))


As you can see, the code is EXACTLY the same, but with only GL_LIGHT1 and the GL_LIGHT0 blocks commented out, no light appears. Is it necessary to enable 0 before 1 is accessible?
_arts_
12-04-2010, 02:01 PM
Just enable lighting before drawing your object, and disable it, just after, that's all and enough :)

So something like this:



drawUnlitObjets();
glEnable (GL_LIGHTING);
glenable (GL_LIGHT{X});
drawLitObjects();
glDisable (GL_LIGHT{X});
glDisable (GL_LIGHTING);
...
Ledivin
12-04-2010, 02:58 PM
Just enable lighting before drawing your object, and disable it, just after, that's all and enough :)

So something like this:



drawUnlitObjets();
glEnable (GL_LIGHTING);
glenable (GL_LIGHT{X});
drawLitObjects();
glDisable (GL_LIGHT{X});
glDisable (GL_LIGHTING);
...

I had actually tried that, so I suppose that links into my second problem... any help?



I've also been having some trouble regarding multiple lights, eg:



glEnable(GL_LIGHT0)
glLight(GL_LIGHT0, GL_POSITION, (0, 1, 1, 0))
glEnable(GL_LIGHT1)
glLight(GL_LIGHT1, GL_POSITION, (0, 1, 1, 0))

glLightfv(GL_LIGHT0, GL_POSITION, (0, 1.5, 1, 0))
glLightfv(GL_LIGHT1, GL_POSITION, (0, 1.5, 1, 0))


As you can see, the code is EXACTLY the same, but with only GL_LIGHT1 and the GL_LIGHT0 blocks commented out, no light appears. Is it necessary to enable 0 before 1 is accessible?
ravage
12-04-2010, 04:51 PM
Is it supposed to be a directional or point light?
Ledivin
12-04-2010, 05:18 PM
That was actually just me testing; in the end, I wanted one object to just be fully lit, which I couldn't find any simple method of doing, except to actually use a light, though I suppose I could also be wrong there.

EDIT: Nevermind... I can't believe I never thought of it, but just disabling lighting while drawing the object does it.... hahaha whoops