# OpenGL openGL errors

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When using the code you download here: http://nehe.gamedev.net/data/lessons/devc/lesson01.zip which uses openGL (lesson 1 code), why do I get the following errors when trying to run it? I'm using Dev-C++ compiler by the way. Also, for Dev-C++ you must #define CDS_FULLSCREEN because Dev-C++ isn't a compiler that already defines it. THIS define is NOT in the downloadable coding for some reason, so you'll have to put it in yourself. C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x38):lesson1.cpp: undefined reference to glViewport@16' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x45):lesson1.cpp: undefined reference to glMatrixMode@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x4d):lesson1.cpp: undefined reference to glLoadIdentity@0' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x84):lesson1.cpp: undefined reference to gluPerspective@32' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x91):lesson1.cpp: undefined reference to glMatrixMode@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x99):lesson1.cpp: undefined reference to glLoadIdentity@0' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0xb7):lesson1.cpp: undefined reference to glShadeModel@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0xd1):lesson1.cpp: undefined reference to glClearColor@16' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0xe0):lesson1.cpp: undefined reference to glClearDepth@8' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0xf0):lesson1.cpp: undefined reference to glEnable@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x100):lesson1.cpp: undefined reference to glDepthFunc@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x115):lesson1.cpp: undefined reference to glHint@8' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x13b):lesson1.cpp: undefined reference to glClear@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x143):lesson1.cpp: undefined reference to glLoadIdentity@0' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x258):lesson1.cpp: undefined reference to wglMakeCurrent@8' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x282):lesson1.cpp: undefined reference to wglDeleteContext@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x854):lesson1.cpp: undefined reference to ChoosePixelFormat@8' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x898):lesson1.cpp: undefined reference to SetPixelFormat@12' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x8ce):lesson1.cpp: undefined reference to wglCreateContext@4' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0x914):lesson1.cpp: undefined reference to wglMakeCurrent@8' C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\ccETaaaa.o(.tex t+0xc2f):lesson1.cpp: undefined reference to SwapBuffers@4'

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Because you're not linking to the OpenGL libraries.

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link the correct opengl libraries ( *.a ), one of nehe's tutorials tells you wich ones.

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I do not see why you are having problems. If you open the "Lesson1.dev" file, it has the correct libraries already in there:

-lopengl32 -lglu32 -lglaux -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -luuid -lodbc32 -lodbccp32

All I had to do was comment out the line:
#include <gl\glaux.h>		// Header File For The Glaux Library`

And that worked for me fine. I just installed Dev-CPP as well, so I havce not made any chagnes to it. I also do not see how you are having troubles with "CDS_FULLSCREEN". In that tutorial they include windows.h, so it is defined already. Once again, I downloaded that link you posted and it compiled without any modifications except removing the glaux.

I'd say make sure you open the "Lesson1.dev" file with Dev-CPP and you should be fine. Make sure you are using the latest Dev-CPP as well. Good luck!

- Drew

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ok, I have been researching this for hours. My brain feels like it's going to leak out of my ear.

I downloaded and unziped http://nehe.gamedev.net/data/lessons/devc/lesson01.zip then opened the project file. Under Project>ProjectOptions and in the "Further object files or linker options" place, there was nothing typed as you said. It was just blank. Also, no code appears to be visible at all either. I try to click on the lesson1.cpp link on the left where the manager colomn is, but nothing happens. I can only see code when I open the lesson1.cpp file specifically.

My way around this: Create a new project and copy/paste code into a new file, then save that project.

~~~~~~~~
NOW... this: http://nehe.gamedev.net/data/lessons/lesson.asp?lesson=01 is the only tutorial or documentation on this website I can find that covers the installation of openGL. It does not specificy where to instal the lib, dll, or h files. I am completely new to this, so I don't know where these go. From my research, I have found that most of the documentations on installing openGL, mention the G++, include, and lib folders, so I just went and installed all the lib, dll, and h files to those locations. I also did not know how to "link" and what specifically NEEDED to be linked. I also found out that the dll files were supposed to go in your system32 folder. I now go to Project>ProjectOptions and under "Further object files or linker options" place, I type -lopengl32 -lglu32 -lglut32 and hit "OK".

Now when I compile, I just get errors like:
(.text+0x854):mycfilename.cpp: undefined reference to 'ChoosePixelFormat@8'
and whatnot. Just three of them though.

SOOOOOoooo..... I never would have guessed this to be this difficult. There are not very many documentations online that go over ALL installation setps for ALL of the files you get and tell you where EXACTLY you're supposed to place the files. This is slightly frustrating because I want to get to coding, not spend countless hours trying to figure out all this stuff my trial and error. But... hopefully I can just get through this soon to get it over with and all will be fine. =)

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Quote:
 Original post by DarkwareI downloaded and unziped http://nehe.gamedev.net/data/lessons/devc/lesson01.zip then opened the project file. Under Project>ProjectOptions and in the "Further object files or linker options" place, there was nothing typed as you said. It was just blank. Also, no code appears to be visible at all either. I try to click on the lesson1.cpp link on the left where the manager colomn is, but nothing happens. I can only see code when I open the lesson1.cpp file specifically.

What the heck? How is that possible? Would you like me to send you the project I have? Maybe some freak occurance happened or something with your Dev-CPP...it is known for instability at times...Anyways, here is my project I downloaded and was able to run with no problems. Open it up and see if it works. If it does not, I would strongly suggest uninstalling your Dev-CPP and installing the newest one, even if you do have the most recent one. Good luck!

- Drew

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hey your file works.... what the heck.... why doesn't mine.... that's weird....

well... I'm going to try and figure out what exactly is going wrong here. If I figure it out, I'll post it back here.

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Quote:
 Original post by DarkwareSOOOOOoooo..... I never would have guessed this to be this difficult. There are not very many documentations online that go over ALL installation setps for ALL of the files you get and tell you where EXACTLY you're supposed to place the files. This is slightly frustrating because I want to get to coding, not spend countless hours trying to figure out all this stuff my trial and error. But... hopefully I can just get through this soon to get it over with and all will be fine. =)

You are putting horse before the cart. You must understand how to do all those steps before you can start CODING. None of that stuff is very hard and if you google enough you will get ALL the info you need, so get going and LEARN the "stuff"

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Quote:
 Original post by Darkwarenow buy NEWEST do you mean the beta version? because I downloaded the one before that because I didn't want a beta

Ahh yes, the Beta! Not version 4. However, I am not a Dev-CPP user for the most part, so you might want to stay with what you are most comfortable with. I'm glad it works though! I can't figure out why it didn't in the first place either, but it *may* be that version of Dev, who knows.

- Drew

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Question: how can the cpp file be the same name as the dev project file? I try to create a new project, then save the cpp file as the same name as the dev project, but it won't let me. How is this done?

Where do you get the MakeFile.win Lesson1.o Lesson1.layout and Lesson1.~cp files? Some of them are encrypted. I tested, and you apparently need the ALL to compile the dev project or else you get errors.

How is the dev project 1.14 Kb, yet when I create a new project, it's only a few bytes? When I open the project, why can't I read the cpp code? why do I have to open the cpp separetly?

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Quote:
 Original post by DarkwareOk, well when I downloaded it, it didn't come with half the files your download file has. o.O so I dunno what the deal was...Question: how can the cpp file be the same name as the dev project file? I try to create a new project, then save the cpp file as the same name as the dev project, but it won't let me. How is this done?Where do you get the MakeFile.win Lesson1.o Lesson1.layout and Lesson1.~cp files? Some of them are encrypted. I tested, and you apparently need the ALL to compile the dev project or else you get errors.How is the dev project 1.14 Kb, yet when I create a new project, it's only a few bytes? When I open the project, why can't I read the cpp code? why do I have to open the cpp separetly?

I would not strongly suggest you ditch your Dev-CPP and get the beta [grin]. Ok, this is what the deal is:

When you download the zip file, it has only has 5 files (the path is different from yours because I downloaded it a few times to make sure it was indeed valid, and it is)

Now when I open up the "lesson1.dev" file, I must comment out that GLaux line. After that I can compile and run.

When I complie, it generates temp files, namely "Lesson1.~cp" and "Lesson1.o". It is just the way Dev-CPP works. They represent the object code files and the ~.cp is a temp file.

Now I mainly suggest that you update your Dev-CPP because you are allowed to have a project named lesson1.dev then have the source file lesson1.cpp, since they are different file names (b/c of extension)

The reason my .dev file is bigger than yours [lol] is because mine has more text in it. I have the linkable libraries already listed and such so I can just ctrl+F10 and it compiles then runs.

The MakeFile.win and Lesson1.layout came with the zip file. Are you sure you are using the link you posted?

If so, upgrade the Dev, and see if your problems are solved. If you have any more questions feel free to ask.

- Drew

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