Making 3D SFML

[Vovosunt]

Over the last month or so I have been trying to make a 3D SFML-like thing (with SFML as the base).

Today I ran into a problem with GLEW while making a 3D version of RenderTarget. I'm not sure which libraries to link/ not link.
Currently I'm only linking the extlibs/libs-msvc/glew.lib (and the standard sfml libs), but it still gives linker errors:

Error   2       error LNK2019: unresolved external symbol "void __cdecl sf::priv::ensureGlewInit(void)" (?ensureGlewInit@priv@sf@@YAXXZ) referenced in function "public: void __thiscall RenderTarget3::resetGLStates(void)" (?resetGLStates@RenderTarget3@@QAEXXZ)     C:\Users\SVS\documents\visual studio 11\Projects\Project1\Project1\RenderTarget3.obj    Project1

Error   3       error LNK2001: unresolved external symbol __imp____glewBlendEquation    C:\Users\SVS\documents\visual studio 11\Projects\Project1\Project1\RenderTarget3.obj    Project1

Error   4       error LNK2001: unresolved external symbol __imp____glewUseProgramObjectARB      C:\Users\SVS\documents\visual studio 11\Projects\Project1\Project1\RenderTarget3.obj    Project1

Error   5       error LNK2001: unresolved external symbol __imp____glewBlendFuncSeparateEXT     C:\Users\SVS\documents\visual studio 11\Projects\Project1\Project1\RenderTarget3.obj    Project1

Error   6       error LNK2001: unresolved external symbol __imp____GLEW_EXT_blend_func_separate C:\Users\SVS\documents\visual studio 11\Projects\Project1\Project1\RenderTarget3.obj    Project1

Error   7       error LNK1120: 5 unresolved externals   C:\Users\SVS\documents\visual studio 11\Projects\Project1\Debug\Project1.exe    Project1
 

Any help would be very appreciated

[Laurent]

If you integrate the sources directly to your project, or link it statically, you must define the GLEW_STATIC macro in your preprocessor options.

[Vovosunt]

That took care of errors 3-7, but error 2 (sf::priv::ensureGlewInit()) still pops up

[Laurent]

That's a private (non exported) SFML function. You mustn't use it.

[Vovosunt]

By removing the ensureGlewInit and by commenting out some openGL ARB functions I managed to get it working.
It's something I guess

What should I do with ensureGlewInit then? Try making my own? Is it even needed?
(During debugging I noticed that it's called like 4 or 5 times every time you draw something O.O)

And how can I get those ext ARB functions to work?
(I get a bad memory acces crash when it tries to use glBlendEquation or glUseProgramObjectARB)

BTW thanks Laurent! You're a goddamn wizard as always

[Laurent]

What should I do with ensureGlewInit then? Try making my own? Is it even needed?

It's a private implementation detail, so... forget it, do your own stuff

And how can I get those ext ARB functions to work?

Aren't you using GLEW for this purpose? Don't forget to call glewInit, and everything should work.

[Grimshaw]

Yep, I do this too. I use sfml and yet I link to glew too and call glewInit after the window is initialized!

It works just fine even though its a little ugly to have the linker warnings all over me..

[Laurent]

What warnings?

[Grimshaw]

2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewUseProgram imported
2>nephilim-d.lib(CGL.obj) : warning LNK4217: locally defined symbol _glewInit imported in function "void __cdecl cglPrepareExtensions(void)" (?cglPrepareExtensions@@YAXXZ)
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewGetActiveUniform imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewGetProgramiv imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewDeleteShader imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewGetShaderInfoLog imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewGetShaderiv imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewCompileShader imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewShaderSource imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewCreateShader imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewDeleteProgram imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewGetProgramInfoLog imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewLinkProgram imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewAttachShader imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewBindAttribLocation imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewCreateProgram imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewUniform1i imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewGetUniformLocation imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewUniformMatrix4fv imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewUniform4fv imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewUniform3fv imported
2>nephilim-d.lib(Shader.obj) : warning LNK4049: locally defined symbol ___glewUniform1f imported
 

But it is normal I believe as GLEW is being linked twice (statically)

[Vovosunt]

Well this is weird... I'm not getting any errors/warnings at all.
Besides using multiple glewInit() should just redefine all the bools and function pointers.
The warnings you get are due to export and then reimport of GLEW "symbols" :

This warning is generated by the linker when you declare a symbol by using the __declspec(dllexport) storage-class attribute in one object file and reference it by using the __declspec(dllimport) attribute in another.]

It's a private implementation detail, so... forget it, do your own stuff

I don't really understand the point of making functions in glCheck private...
They're pretty simple and are just for error checking anyway :\

Now, ensureGLcontext is another thing
It's pretty damn complicated...
setActive is there to make SFML thread safe, istn it? 
Anyway...

glewInit() did the trick and it seems that everything is working fine
Thanks again Laurent!

BTW can I use GLresource for Vertex/Pixel buffer implementations?
It's basically a thread-safe counter for the openGL resources if I understand everything right.

[Laurent]

BTW can I use GLresource for Vertex/Pixel buffer implementations?

Yes.