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Squaglia

OpenGL help with glMatrixMode

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Squaglia    100
Hi. I know that this is a very simple question, i have used Google and searched the forum but i cant see where is the problem in this code. what i want to archive is show some text in the screen just like a HUD, but for debugging purposes. The problem is that if i show the text on screen the 3d models don't get drawn, but if i comment the text functions. everything works ok, So i think i am doing some nasty things with the glMatrixMode glPopMatrix and glPushMatrix. This are the relevant code snippets. this is the drawing function
bool Application::DrawWorld() {

glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear Screen And Depth Buffer

/// begin text
/// backup current model-view matrix
glPushMatrix();                     // save current modelview matrix
glLoadIdentity();                   // reset modelview matrix
glMatrixMode(GL_PROJECTION);        // switch to projection matrix
glPushMatrix();                     // save current projection matrix
glLoadIdentity();                   // reset projection matrix
glOrtho(0,SCREEN_WIDTH,0,SCREEN_HEIGHT,-1,1);  // set the projection

glColor3f(1.0f, 1.0f, 1.0f);

freetype::print(myFont, 0, 90, "ViewAngleHor: %f", ViewAngleHor );
freetype::print(myFont, 0, 70, "ViewAngleVer: %f", ViewAngleVer );
freetype::print(myFont, 0, 50, "X: %f", X );
freetype::print(myFont, 0, 30, "Y: %f", Y );
freetype::print(myFont, 0, 10, "Z: %f", Z );

/// restore projection matrix
glPopMatrix();                   // restore to previous projection matrix

// end text

glMatrixMode(GL_MODELVIEW);      // switch to modelview matrix
glPopMatrix();                   // restore to previous modelview matrix
glLoadIdentity();		// Reset The Modelview Matrix
glPushMatrix();			// save current modelview matrix
  
  glRotated(ViewAngleVer, 1, 0, 0);
  glRotated(ViewAngleHor, 0, 1, 0);
  glTranslated(-X, -Y, -Z);
  
  glBegin(GL_QUADS);
    glColor4f(.0f, 0.5f, 1.0f, 1.0f);
    glNormal3f(0.0f,1.0f,0.0f);
    glVertex3f(X-1000.0f, -0.1f, Y-1000.0f);
    glVertex3f(X-1000.0f, -0.1f, Y+1000.0f);
    glVertex3f(X+1000.0f, -0.1f, Y+1000.0f);
    glVertex3f(X+1000.0f, -0.1f, Y-1000.0f);
  glEnd();

glPopMatrix();


return true;
}

And as a reference this is the freetype::print function
void print(const font_data &ft_font, float x, float y, const char *fmt, ...)  {

	pushScreenCoordinateMatrix();

	GLuint font=ft_font.list_base;
	float h=ft_font.h/.63f;			

	char		text[256];		
	va_list		ap;			

	if (fmt == NULL)			// If There's No Text
		*text=0;			// Do Nothing

	else {
	va_start(ap, fmt);			// Parses The String For Variables
	    vsprintf(text, fmt, ap);		// And Converts Symbols To Actual Numbers
	va_end(ap);				// Results Are Stored In Text
	}
	const char *start_line=text;
	vector<string> lines;

	const char * c = text;;

	for(;*c;c++) {
		if(*c=='\n') {
			string line;
			for(const char *n=start_line;n<c;n++) line.append(1,*n);
			lines.push_back(line);
			start_line=c+1;
		}
	}
	if(start_line) {
		string line;
		for(const char *n=start_line;n<c;n++) line.append(1,*n);
		lines.push_back(line);
	}

	glPushAttrib(GL_LIST_BIT | GL_CURRENT_BIT  | GL_ENABLE_BIT | GL_TRANSFORM_BIT);
	glMatrixMode(GL_MODELVIEW);
	glDisable(GL_LIGHTING);
	glEnable(GL_TEXTURE_2D);
	glDisable(GL_DEPTH_TEST);
	glEnable(GL_BLEND);
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

	glListBase(font);

	float modelview_matrix[16];
	glGetFloatv(GL_MODELVIEW_MATRIX, modelview_matrix);

	for(unsigned int i=0;i<lines.size();i++) {
		glPushMatrix();
		glLoadIdentity();
		glTranslatef(x,y-h*i,0);
		glMultMatrixf(modelview_matrix);

		glCallLists(lines[i].length(), GL_UNSIGNED_BYTE, lines[i].c_str());
		glPopMatrix();
	}

	glPopAttrib();
	pop_projection_matrix();
}

I really dont know what to do, i have tried everything i could think of with no success. I'm just learning my way into Opengl and c++ so the problem might be obvious to you. Thanks. PS. English is not my native language. I hope that this lines clearly represent the problem and that the grammar is not to horrible.

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bitshifter    113
Lets assume nothing, and start from there...

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(...);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

// TODO: Render 3D stuff here...

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(...);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

// TODO: Render 2D stuff here...

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Squaglia    100
Thank you for your response.
i'm having the same problem with this code in this case i can only see the text.
If i comment out the 2D part the 3D starts working.



glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective( 45.0f, (SCREEN_WIDTH/SCREEN_HEIGHT), 0.1f, 10000.0f );
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();


glRotated(ViewAngleVer, 1, 0, 0);
glRotated(ViewAngleHor, 0, 1, 0);
glTranslated(-X, -Y, -Z);

glBegin(GL_QUADS);
glColor4f(.0f, 0.5f, 1.0f, 1.0f);
glNormal3f(0.0f,1.0f,0.0f);
glVertex3f(X-1000.0f, -0.1f, Y-1000.0f);
glVertex3f(X-1000.0f, -0.1f, Y+1000.0f);
glVertex3f(X+1000.0f, -0.1f, Y+1000.0f);
glVertex3f(X+1000.0f, -0.1f, Y-1000.0f);
glEnd();

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0,SCREEN_WIDTH,0,SCREEN_HEIGHT,-1,1);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

freetype::print(myFont, 0, 90, "ViewAngleHor: %f", ViewAngleHor );
freetype::print(myFont, 0, 70, "ViewAngleVer: %f", ViewAngleVer );
freetype::print(myFont, 0, 50, "X: %f", X );
freetype::print(myFont, 0, 30, "Y: %f", Y );
freetype::print(myFont, 0, 10, "Z: %f", Z );


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