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HopeDagger

OpenGL [Solved] wglUseBitmapFonts() not available with SDL?

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HopeDagger    970
Greetings! I am currently developing with the infamous SDL+OpenGL library combination, and am at the point where I need to get some text going onscreen. From the various font-rendering methods available via OpenGL, I found bitmap fonts the most viable. And yes, I'm developing on Windows. [smile] However, I can't seem to get a darn thing rendering. Here's what I'm using to initialize the fonts and draw them (mostly pulled from NeHe #13):
void GUI::InitFont()
{
	HFONT font, oldfont;

	fontbase = glGenLists(96);

	font = CreateFont(-24, 0, 0, 0, 
					  FW_BOLD, FALSE, FALSE, FALSE,
					  ANSI_CHARSET, OUT_TT_PRECIS, CLIP_DEFAULT_PRECIS,
					  ANTIALIASED_QUALITY, FF_DONTCARE|DEFAULT_PITCH,
					  "Courier New");

	SDL_SysWMinfo wmInfo;
	SDL_GetWMInfo(&wmInfo);
	HWND hWnd = wmInfo.window;
	
	HDC hDC = GetDC(hWnd);  // This seems to be returning NULL :(
	if( hDC != NULL )
	{
	oldfont = (HFONT)SelectObject( hDC, font );
	wglUseFontBitmaps(hDC, 32, 96, fontbase);
	//wglUseFontBitmaps(hDC, 0, 255, fontbase);
	SelectObject(hDC, oldfont);
	DeleteObject(font);
	}
	else
		gLog.Write("OMG! WTF?!", LOG_ERROR);
}


void GUI::DrawText(std::string txt, int x, int y)
{
	glColor3f(1,1,1);

	glRasterPos2f(x,y);   // I'm using a 2D ortho viewport, so the coordinates are valid

	glPushAttrib(GL_LIST_BIT);
	glListBase(fontbase - 32);
	glCallLists(txt.length(), GL_UNSIGNED_BYTE, txt.c_str());
	glPopAttrib();
}


Are wgl functions unavailable when SDL is being used, or am I missing something vital? This one's been gnawing at me all afternoon, hehe. [smile] Any and all help is greatly appreciated! Further clarification of any parts is unhesitantly available upon request. [Edited by - HopeDagger on August 16, 2006 10:28:28 PM]

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wyrzy    430
If GetDC() is returning NULL, I'm guessing its not an SDL problem.

Try using: HDC hdc = wglGetCurrentDC();

This way you won't need an HWND. I'm using that function with SDL and OpenGL and it works for me.

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HopeDagger    970
Quote:
Original post by wyrzy
If GetDC() is returning NULL, I'm guessing its not an SDL problem.

Try using: HDC hdc = wglGetCurrentDC();

This way you won't need an HWND. I'm using that function with SDL and OpenGL and it works for me.


Aye. I tried wglGetCurrentDC(), which does return a valid HDC for me. However, I still result with no text displaying. :-/

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Kalidor    1087
Quote:
Original post by HopeDagger
Fixed. Turns out it doesn't work unless GL_TEXTURE_2D is disabled. Go figure, huh? [smile]
Just to clarify this... it still "works" with texturing enabled, it just goes through the texturing stage. So any texture that's bound will be sampled at whatever the current texture coordinate is for the texture unit it is bound to, and that color will be applied to the font in the way that the current texture environment settings specify.

Having lighting enabled can also make it appear to "not work," even though OpenGL is doing exactly what it was told to (ie: apply lighting to the font).

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Miklas    364
Sorry to bust this topic back open, but my hdc seems to be NULL all the time. I've tried on both ways

[CODE]
SDL_SysWMinfo wmInfo;
SDL_GetWMInfo(&wmInfo);
HWND hWnd = wmInfo.window;
HDC hDC = GetDC(hWnd);
[/CODE]

and

[CODE]
HDC hDC= wglGetCurrentDC();
[/CODE]

I've read some things on this forum, for instance that you have to create the window in the same thread. As I have the same way of OP (I'm also using SDL+OpenGL combo), I guessed the problem is somewhere else, but I can't seem to find it.[img]http://public.gamedev.net//public/style_emoticons/default/sad.png[/img]

Edit: after a few hours of looking, I found my problem. It was quite stupid. I tried to get the fonts before SDL_SetVideoMode. :)

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