18 replies to this topic

[Phynix]

Where can I download opengl 2.0 or later? The opengl that came with vc++ was version 1.1, and for some reason i couldn't find it on the opengl website.

[Steve132]

OpenGL 2.0 and higher isn't "downloaded" as such...the headers may or may not be downloaded from openGL.org, or installed with your graphics vendors SDK, but the actual code for OpenGL that you link with is a part of your graphics hardware's graphics subsystems. You may need to use a library like GLEW

[frca]

You need to download GLEW library or similar, it adds functionality of newer versions of OpenGL. It's a wrapper around OpenGL extension mechanism. That means you can only use the functionality your graphics card/driver supports.

[Phynix]

OK, thanks for the quick replies. The reason I'm asking is that before I had vista, and I was able to use glsl, as I had opengl 2.0 and GLEW_ARB_vertex_shader & GLEW_ARB_fragment_shader extensions available. However, after upgrading to windows 7, I didn't. I'm going back to glsl now, and I can't find a way of using it. I have glew installed.

[V-man]

Everything is explained in the wiki
http://www.opengl.org/wiki/Getting_started

[Phynix]

OK. Well it's sorta weird. Over at the exe file that can be downloaded from Nehe lesson 24 (http://nehe.gamedev.net/data/lessons/lesson.asp?lesson=24), it says that I have the extensions required, and that I have version 3.2.0. However, my version of GL.h says "#define GL_VERSION_1_1." Also, I cannot use those extensions via the code at http://www.lighthouse3d.com/opengl/glsl/index.php?ogloverview:

#include <GL/glew.h>
#include <GL/glut.h>

void main(int argc, char **argv) {

glutInit(&argc, argv);

...

glewInit();
if (GLEW_ARB_vertex_shader && GLEW_ARB_fragment_shader)
printf("Ready for GLSL\n");
else {
printf("Not totally ready :( \n");
exit(1);
}

setShaders();

glutMainLoop();
}

or the other (opengl 2.0 version; I didn't feel like pasting it here for space purposes) But I really have no clue what's going on right now.

[Oberon_Command]

Quote:

Original post by http://www.opengl.org/wiki/Getting_started Microsoft will never update gl.h and opengl32.lib that comes with their compiler. It hasn't been updated since 1995. Basically, the solution is to use glext.h and wglext.h (wglext.h is for Windows only) which define all the GL 1.2, 1.3, 1.4, 1.5, 2.0, 2.1 and above tokens and functions.

[wink]

[Phynix]

Thanks Oberon_Command. My guess is to just include the *.h files (wglext, glext, and glxext) to my source, right? Are there any libs that come with the source or anything like that?

The reason I'm asking is because it doesn't work :( I create a windows console app, put this code in, change the linker input properties, and run the file.

#include <GL/glew.h>
#include <GL/glut.h>
#include "wglext.h"
#include "glext.h"
#include <iostream>
using namespace std;
void main(int argc, char **argv) {
glutInit(&argc, argv);
glewInit();
if (GLEW_ARB_vertex_shader && GLEW_ARB_fragment_shader)cout <<("Ready for GLSL\n");
else cout<<("Not totally ready :( \n");
char c;cin>>c;
}

It doesn't work. or at least it prints "Not totally ready :(".

[Brother Bob]

You need to create a window also, or you don't have a rendering context to work with.

[Phynix]

oh....lol....you can tell I'm new to graphics theory and the OpenGL pipeline and all the other lower level elements. But thanks it works now!

[Phynix]

This may be another simple question, but it's not working again:

Once again, it's not working. I put the code:

string prnt="FPS: %2i | %2i | Room: "+map.currentRoom().getName();
if(glewIsSupported("GL_VERSION_2_0"))glewsupported=true;
if(glewsupported)prnt.append(" glew: supported");
else prnt.append(" glew: not supported");
glPrint(prnt.c_str(), FPS.count, FPS.frames);

And it fails. I am using the same tests as in my console application, except this time from a win32 application. The code above is in my render function, and thus gets called every frame after the window is created. Do I need to somehow link the window to glew?

[rip-off]

When you say "it fails", what do you mean? Runtime error, compile error? Nothing printed? IS glPrint from NeHe, in which case did you BuildFont?

[Phynix]

Sorry for the confusion. By 'fails,' I just meant that it said glewsupported is false. I created the window and all, just as Brother Bob advised, but it isn't returning true when i call the glewIsSupported function.

[iliak]

Maybe obvious... Did you upgrade your video drivers ?

[V-man]

You need to make sure the right GL version is there in order to use GLSL.
You need 2.0 minimum.
Check with glGetString(GL_VERSION)

[Phynix]

Yes, I did update the most recent video drivers from nVidia, and it says that I have version 3.2.0 when I call glGetString(GL_VERSION). What I'm thinking is that like Brother Bob said, I think it's a problem with linking the context somehow; I would think it's linked since it displays an opengl scene, but it says I don't have support for it.

[V-man]

Since GL 3.2 is > 2.0, you have support for it.

[Phynix]

V-man: Yes, I realize I have support for it. The question I have is why it says that I don't have support for it. I would like to know what exactly is wrong with my code, and why wgl says that I don't have support for it.

[V-man]

Are you saying glewIsSupported("GL_VERSION_2_0") returns false?

Maybe update GLEW.
I use GLEW but I don't use glewIsSupported. I never had problems.