
<?php

include ("diagram.php");



function MyXScale($xx)

{ $vv=round($xx*4/pi());

  if ($vv==0) return(0);

  if ($vv==4) return("pi");

  if ($vv==8) return("2 pi");

  if ($vv%2==0) return(strval($vv/2) ."/2 pi");

  return($vv ."/4 pi");

}



$D=new Diagram();

$D->Img=@ImageCreate(700, 400) or die("Cannot create a new GD image."); 

ImageColorAllocate($D->Img, 255, 255, 255); //background color



$D->SetFrame(80, 40, 540, 340);

$D->SetBorder(0, 2*pi(), -1, 1);

$D->SetText("", "", "some functions");

$D->XGridDelta=pi()/4;

$D->XScale="function MyXScale";

$D->YGridDelta=0.2;

$D->YSubGrids=2;

$D->SetGridColor("#FFFFFF", "#EEEEEE");

$D->Draw("#DDDDDD", "#000000", false);

for ($i=80; $i<=540; $i++)

{ $x = $D->RealX($i);

  $j = $D->ScreenY(sin($x));

  $D->Pixel($i, $j, "#FF0000");

  $j= $D->ScreenY(cos($x));

  $D->Pixel($i, $j, "#0000FF");

}

$D->Bar(560, 100, 680, 120, "#0000FF", "f(x)=cos(x)", "#FFFFFF");

$D->Bar(560, 160, 680, 180, "#FF0000", "f(x)=sin(x)", "#000000");



ImagePng($D->Img, "pixel_object.png");

ImageDestroy($D->Img);

?>

<HTML><HEAD></HEAD>

<BODY bgcolor="#eeeeee">

<table border=1><tr><td><IMG src="pixel_object.png"></td></tr></table>

</BODY>

</HTML>