Text Won't Overlap 2D Quad

Started by
1 comment, last by ajm113 11 years, 7 months ago
Hello everyone, I seem to be having a small problem with my font system not overlapping the quad I'm trying to draw that shows the background image for my menu system. I've tried moving around the glDisable GL_DEPTH_TEST and disabled DepthMask and a few other things and even rearranged the order of how the 2D stuff gets displayed, but I'm getting no effect from anything.

Here is my code


void Render()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glEnable(GL_BLEND);
glClearColor( 0.0f, 0.0f, 0.0f, 0.0f );

//Draw 3D here....

//Draw 2D here...

glEnable(GL_TEXTURE_2D);
glEnable(GL_BLEND);
glDisable(GL_DEPTH_TEST);

glColor3f(1, 1, 1);
glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glPushMatrix(); // Store The Projection Matrix
glLoadIdentity(); // Reset The Projection Matrix
glOrtho(0,640,0,480,-1,1); // Set Up An Ortho Screen
glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glPushMatrix(); // Store The Modelview Matrix
glLoadIdentity(); // Reset The Modelview Matrix
glTranslated(0,0,0); // Position The Text (0,0 - Bottom Left)
glBindTexture(GL_TEXTURE_2D, 1);

glBegin(GL_QUADS);

glTexCoord2f(0, 1.0);
glVertex2i(0, 0);

glTexCoord2f(1,1.0);
glVertex2i(30, 0);

glTexCoord2f(1.0, 0.0);
glVertex2i(30, 30);

glTexCoord2f(0.0, 0.0);
glVertex2i(0, 30);

glEnd();
}
glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glPopMatrix(); // Restore The Old Projection Matrix
glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glPopMatrix(); // Restore The Old Projection Matrix
glDisable(GL_TEXTURE_2D);
glDisable(GL_BLEND);

glColor3f(1, 0, 1);
m_FontEngine.glPrint(20, 20, "Hello Menu!", 0);
glEnable(GL_DEPTH_TEST); // Enables Depth Testing

}



Code of glPrint:

if (set>1)
{
set=1;
}
glEnable(GL_TEXTURE_2D);
glEnable(GL_BLEND);

glBlendFunc(GL_SRC_ALPHA,GL_ONE); // Select The Type Of Blending

glBindTexture(GL_TEXTURE_2D, FontTextureId); // Select Our Font Texture
glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glPushMatrix(); // Store The Projection Matrix
glLoadIdentity(); // Reset The Projection Matrix
glOrtho(0,640,0,480,-1,1); // Set Up An Ortho Screen
glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glPushMatrix(); // Store The Modelview Matrix
glLoadIdentity(); // Reset The Modelview Matrix

glTranslated(x,y,0); // Position The Text (0,0 - Bottom Left)

glListBase(base-32+(128*set)); // Choose The Font Set (0 or 1)

glCallLists(strlen(string),GL_UNSIGNED_BYTE,string);// Write The Text To The Screen

glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glPopMatrix(); // Restore The Old Projection Matrix
glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glPopMatrix(); // Restore The Old Projection Matrix


glDisable(GL_TEXTURE_2D);
glDisable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);


I think it may have something to do with how I'm setting up the projects on both of them, but I don't know what else it could be.

Thank you.
Check out my open source code projects/libraries! My Homepage You may learn something.
Advertisement
Have you tried changing this line:
glBlendFunc(GL_SRC_ALPHA,GL_ONE); // Select The Type Of Blending

to

glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA); // Select The Type Of Blending

Because IIRC, the way you have it will make it so the color components add together. Since you're rendering on white, everything will be white because white = 1,1,1 and color values get truncated at 1.

Also, you seem to have a lot of extraneous state changes in your code. You should generally avoid making more state changes than you have to.

Learn to make games with my SDL 2 Tutorials

I tried changing, it appears to fix this problem, but then it created another one where the alpha wasn't working anymore since I was using a .bmp file with a black background. So just to fix everything and even get a better looking font, I just went ahead and changed the bmp to a png file with a transparent background for the text and that pretty much toke care of it. I even tried turning on alpha test and it didn't do anything, but anyways I'll clean up the code.

Thanks for your help once again! smile.png
Check out my open source code projects/libraries! My Homepage You may learn something.

This topic is closed to new replies.

Advertisement