OpenGl Rendercontex schützen

[EWeiss]

Ich setze auf einen OpenGl Rendercontex eine Progressbar auf
Leider zerstört meine function die Zorder der Plugins und verändert auch diverse andere Dinge
Gibt es eine möglichkeit die vom Plugin zu schützen wenn ich meine drüber setze ?

Delphi-Quellcode:

procedure DrawPosition;
Var
    x1,x2,
  x12,x21,
  z1,y1,
  y2,x,y,hd : GLfloat;
  d1,d2    : GLfloat;
  overdraw : GLfloat;

begin

  glMatrixMode(GL_PROJECTION); //--> zerstört die z order
  glLoadIdentity;
  gluPerspective(45, BassBoxInfo^.w / BassBoxInfo^.h, 1, 1000.0);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity;

  d1 := 0.05;
  d2 := 0.01;
  overdraw := 0.03;

   glDepthMask(ByteBool(GL_FALSE));
   glDisable(GL_LIGHTING);
   glEnable(GL_BLEND);
   glBlendFunc(GL_ONE, GL_ONE);

   glBindTexture(GL_TEXTURE_2D, BarTexture);
   glColor4f( 1.0, 1.0, 1.0, 0.0);

   z1  := -4.0;
   y1  := -1.65;
   y2  := y1 + d1 - d2 + overdraw;
   x1  := -2.21;
   x2  := 2.20;
   x12 := x1 + (d1 - d2) * 0.3;
   x21 := x2 - (d1 - d2) * 0.3;

   glBegin(GL_QUADS);

      glTexCoord2f(0.0, 0.0);
      glVertex3f(x1, y2, z1);
      glTexCoord2f(1.0, 0.0);
      glVertex3f(x1, y1, z1);
      glTexCoord2f(1.0, 0.3);
      glVertex3f(x12, y1, z1);
      glTexCoord2f(0.0, 0.3);
      glVertex3f(x12, y2, z1);
      glTexCoord2f(0.0, 0.3);
      glVertex3f(x12, y2, z1);
      glTexCoord2f(1.0, 0.3);
      glVertex3f(x12, y1, z1);
      glTexCoord2f(1.0, 0.7);
      glVertex3f(x21, y1, z1);
      glTexCoord2f(0.0, 0.7);
      glVertex3f(x21, y2, z1);
      glTexCoord2f(0.0, 0.7);
      glVertex3f(x21, y2, z1);
      glTexCoord2f(1.0, 0.7);
      glVertex3f(x21, y1, z1);
      glTexCoord2f(1.0, 1.0);
      glVertex3f(x2, y1, z1);
      glTexCoord2f(0.0, 1.0);
      glVertex3f(x2, y2, z1);

   glEnd();

   glBindTexture(GL_TEXTURE_2D, PeaksTexture);

   hd :=(d1 - d2) * 4.0;
   x  :=(x2 - x1) * CurrentPositionPart + x1;
   y  :=(y2 + y1) * 0.5;

   glBegin(GL_QUADS);
  glTexCoord2f(0.0, 0.0);
  glVertex3f(x - hd, y - hd, z1);
  glTexCoord2f(0.0, 1.0);
  glVertex3f(x - hd, y + hd, z1);
  glTexCoord2f(1.0, 1.0);
  glVertex3f(x + hd, y + hd, z1);
  glTexCoord2f(1.0, 0.0);
  glVertex3f(x + hd, y - hd, z1);
  glEnd();

  glDepthMask(ByteBool(GL_TRUE));
 //   glDisable(GL_BLEND); --> zerstört das GL_Blend vom Plugin

end;

gruss Emil