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Kustaz

OpenGL Outline fonts not drawing

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Kustaz    178
Hi, I've been trying to implement outline fonts in my project lately, and as far as I can tell, theyre not being drawn at all. I think it has something to do with glOrtho(), but thats a bit of a stab in the dark. I have also ensured every glPopMatrix() is matched with a glPushMatrix(). Due to the size of my project, it makes no sense for me to post all my code. But, I will try and show everything relevent. If there is anything else you need to see, just ask. The text is stored in these variables:
GLuint Font;
GLYPHMETRICSFLOAT GMFBuffer[256];


And is rendered like this:

GLEnable2D(1280, 1024);
glDisable(GL_TEXTURE_2D);// disable Texture Mapping 


	glPushMatrix();

        glLoadIdentity();

	glColor4f(1.0f, 1.0f, 1.0f, 1.0f);

	glTranslatef(50.0f, 50.0f, 0);

	GLPrintStringOL(Target.Font, "neeber");

	glPopMatrix();

glEnable(GL_TEXTURE_2D);// Enable Texture Mapping 
GLDisable2D();


The text is created using this function:

//*************************************************************************************//
//********************************CREATE AN OUTLINE FONT*******************************//
//*************************************************************************************//

unsigned int CreateOutlineFont(char *fontName, int fontSize, float Extrusion, int Format, GLYPHMETRICSFLOAT *GMFBuffer, HDC hDevCon)
{

	HFONT hFont;         // windows font
	unsigned int base;

	base = glGenLists(256);      // create storage for 96 characters

	if (stricmp(fontName, "symbol") == 0)
	{
	     hFont = CreateFont(fontSize, 0, 0, 0, FW_BOLD, FALSE, FALSE, FALSE, SYMBOL_CHARSET, 
							OUT_TT_PRECIS, CLIP_DEFAULT_PRECIS, ANTIALIASED_QUALITY,
							FF_DONTCARE | DEFAULT_PITCH, fontName);
	}
	else
	{
		 hFont = CreateFont(fontSize, 0, 0, 0, FW_BOLD, FALSE, FALSE, FALSE, ANSI_CHARSET, 
							OUT_TT_PRECIS, CLIP_DEFAULT_PRECIS, ANTIALIASED_QUALITY,
							FF_DONTCARE | DEFAULT_PITCH, fontName);
	}

	if (!hFont)
		return 0;

	SelectObject(hDevCon, hFont);
	wglUseFontOutlines(hDevCon, 0, 255, base, 0.0f, Extrusion, Format, GMFBuffer);



	return base;

}



Like this:
Font = CreateOutlineFont("Console", 150, 0.0f, WGL_FONT_POLYGONS, GMFBuffer, hDevCon);



The text is drawn using this function:
//*************************************************************************************//
//*******************************PRINT AN OUTLINE FONT*********************************//
//*************************************************************************************//

void GLPrintStringOL(unsigned int Base, char *str)
{

	if(str == NULL)
	return;

	//draw the text
	glPushAttrib(GL_LIST_BIT);
		glListBase(Base);
		glCallLists(strlen(str), GL_UNSIGNED_BYTE, str);
	glPopAttrib();

}



The following flags are enabled when OpenGL is initialised: glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glEnable(GL_TEXTURE_2D); glShadeModel(GL_SMOOTH); glClearColor(0.0f, 0.0f, 0.0f, 0.5f); glClearDepth(1.0f); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glEnable(GL_COLOR_MATERIAL); The 2D perspective functions look like this:
//*************************************************************************************//
//******************************ENABLE 2D DRAWING MODE*********************************//
//*************************************************************************************//

void GLEnable2D(long ScreenResX, long ScreenRezY)
{
	int vPort[4];//space for the viewport data

   glGetIntegerv(GL_VIEWPORT, vPort);//get the viewport data

   glMatrixMode(GL_PROJECTION);//set the matrix mode
   glPushMatrix();//push the matrix onto the stack
   glLoadIdentity();//load the default identity

   glOrtho(0, ScreenResX, ScreenRezY, 0, -10, 10);//set our frindly little fella to ortho
   glMatrixMode(GL_MODELVIEW);//set the matrix mode
   glPushMatrix();//push the matrix onto the stack
   glLoadIdentity();//now load the default
}

//*************************************************************************************//
//*****************************DISABLE 2D DRAWING MODE*********************************//
//*************************************************************************************//

void GLDisable2D()
{
   glMatrixMode(GL_PROJECTION);//set the matrix mode
   glPopMatrix();  //pop it back to last position, i love this function 
   glMatrixMode(GL_MODELVIEW);//set the matrix mode again
   glPopMatrix();//now pop it again

// no need to return a value
}


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Seroja    280
Check for errors in CreateOutlineFont, some function could simply fail there.
You could also disable GL_LIGHTING and try that with simply color.

My guess would be that it is because of the size of the glyphs you create. I didn't get it completely, but I still think it depends on the size of your viewport/projection.

Try:
1) Scale the font before drawing (enlarge / shrink)
2) Scale the viewport (it's ortho, try -1,1,-1,0 or 0,1,0,1) and then again scale the font.

Other than that, update your drivers :P

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ttddc    122
hey!I'm a new , and I'm not sure this will help or not.
well ,I got some code several days ago.I'm glad to show them :) here:


void OpenGLFont::showText3D(HFONT hFont, const char* str, float z)
{
if(strlen(str) >=MAX_OPENGL_FONT_NUM) return;

unsigned char* pChar =new unsigned char[MAX_OPENGL_FONT_NUM];
HDC hdc = wglGetCurrentDC();
HFONT hOldFont = (HFONT)SelectObject(hdc, hFont);
strcpy((char*)pChar, str);

int n,len = strlen(str);
unsigned long dwChar = 0;
GLYPHMETRICSFLOAT pgmf[1];

pushStatus();
glPushMatrix();
for(int i = 0; i < len; i++)
{
if(IsDBCSLeadByte((unsigned char)pChar[i]))
{
dwChar = (unsigned long)pChar[i];
dwChar = dwChar<<8;
dwChar = dwChar | pChar[i+1];
i++;
}
else
dwChar = pChar[i];
n = glGenLists(1);
wglUseFontOutlines(
hdc,
dwChar,
1,
n,
0.0f,
z,
WGL_FONT_POLYGONS,
pgmf);
glCallList(n);
glDeleteLists(n , 1);
}
glPopMatrix();
popStatus();

delete pChar;
SelectObject(hdc, hOldFont);
}


And they worked well,and of course as you've seen ,you can draw 3D font(no matter ASCII and UNICODE).

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Kustaz    178
Paydirt! Thank you, I have found that it is due to my glOrtho() projection, and it is drawing it, just realy realy small in the corner. I scaled it, and it looks fine. Thank you!

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