<?php
$pts = array();
for($i=-1440; $i <= 1440; $i+=60){
	$pts[] = deg2rad($i)*2;
	$pts[] = sin(deg2rad($i))*2;
}

draw_graph(1014, 600, 30, $pts, true, true, true, true);

// $w -- ширина графика
// $h -- высота графика
// $s -- кол-во пикселей в одном делении
// $pts -- массив с точками в формате array(x1, y1, x2, y2, x3, x3, ...), где тч. n(xn, yn)
// $grid -- нарисовать сетку
// $small_grid -- нарисовать сетку, если в делении больше 20 пикселей
// $point -- рисовать точку в месте сгиба
// $point_info -- отобразить рядом с точкой её координаты
function draw_graph($w, $h, $s, $pts, $grid, $small_grid, $point, $point_info){
	$image = imagecreate($w, $h);
	imageantialias($image, true);
	$color_body = imagecolorallocate($image, 0xFF, 0xFF, 0xFF);
	$color_line = imagecolorallocate($image, 0x00, 0x00, 0x00);
	$color_graph = imagecolorallocate($image, 0xFF, 0x00, 0x00);
	$color_grid = imagecolorallocate($image, 0xCC, 0xCC, 0xCC);
	$color_text = imagecolorallocate($image, 0xFF, 0x44, 0x44);
	imagefilledrectangle($image, 0, 0, $w, $h, $color_body);
	$graph_font = 'tahoma.ttf';
	$x0 = $w/2;
	$y0 = $h/2;
	if ($grid){
		for ($i = 0, $j=1; $i < $x0; $i+=$s, $j++){
			$x = $i + $x0;
			$x2 = -$i + $x0;
			imageline($image, $x, 0, $x, $h, $color_grid);
			imageline($image, $x2, 0, $x2, $h, $color_grid);
			if ($small_grid && $s >= 20){
				for ($n = $x+$s/5; $n < $x+$s; $n += $s/5) imageline($image, $n, 0, $n, $h, $color_grid);
				for ($n = $x2-$s/5; $n > $x2-$s; $n -= $s/5) imageline($image, $n, 0, $n, $h, $color_grid);
			}
		}
		for ($i = 0, $j=1; $i < $y0; $i+=$s, $j++){
			$y = -$i + $y0;
			$y2 = $i + $y0;
			imageline($image, 0, $y, $w, $y, $color_grid);
			imageline($image, 0, $y2, $w, $y2, $color_grid);
			if ($small_grid && $s >= 20){
				for ($n = $y-$s/5; $n > $y-$s; $n -= $s/5) imageline($image, 0, $n, $w, $n, $color_grid);
				for ($n = $y2+$s/5; $n < $y2+$s; $n += $s/5) imageline($image, 0, $n, $w, $n, $color_grid);
			}
		}
	}
	for ($i = $s, $j=1; $i < $x0; $i+=$s, $j++){
		$x = $i + $x0;
		$x2 = -$i + $x0;
		imageline($image, $x, $y0-$s/2, $x, $y0+$s/2, $color_line);
		imageline($image, $x2, $y0-$s/2, $x2, $y0+$s/2, $color_line);
		$font_size = $s/3;
		if ($font_size < 5 && $s >= 6) $font_size = 5;
		$font = imagettfbbox($font_size, 0, $graph_font, $j);
		imagettftext($image, $font_size, 0, $x+2, $h/2+($font[0]-$font[7])+2, $color_line, $graph_font, $j);
		imagettftext($image, $font_size, 0, $x2+2, $h/2+($font[0]-$font[7])+2, $color_line, $graph_font, '-'.$j);
	}
	for ($i = $s, $j=1; $i < $y0; $i+=$s, $j++){
		$y = -$i + $y0;
		$y2 = $i + $y0;
		imageline($image, $x0-$s/2, $y, $x0+$s/2, $y, $color_line);
		imageline($image, $x0-$s/2, $y2, $x0+$s/2, $y2, $color_line);
		imagettftext($image, $font_size, 0, $w/2+3, $y-3, $color_line, $graph_font, $j);
		imagettftext($image, $font_size, 0, $w/2+3, $y2-3, $color_line, $graph_font, '-'.$j);
	}
	imageline($image, $w/2, 0, $w/2, $h, $color_line);
	imageline($image, 0, $h/2, $w, $h/2, $color_line);
	imageline($image, ($w-$s)/2, $s/2, $w/2, 0, $color_line);
	imageline($image, $w/2, 0, ($w+$s)/2, $s/2, $color_line);
	imageline($image, $w-$s/2, ($h-$s)/2, $w, $h/2, $color_line);
	imageline($image, $w-$s/2, ($h+$s)/2, $w, $h/2, $color_line);
	$font_size = $s*0.75;
	if ($font_size < 6) $font_size = 6;
	imagettftext($image, $font_size, 0, $w/2+$s+3, 2+$s*0.75, $color_line, $graph_font, 'y');
	$font = imagettfbbox($font_size, 0, $graph_font, 'x');
	imagettftext($image, $font_size, 0, $w-3-($font[2]-$font[0]), ($h+$s)/2+($font[0]-$font[7])+3, $color_line, $graph_font, 'x');

	$x_last = $pts[0]*$s + $x0;
	$y_last = -$pts[1]*$s + $y0;
	for ($i=1; $i <= count($pts); $i+=2){
		$x = $pts[$i-1]*$s + $x0;
		$y = -$pts[$i]*$s + $y0;
		imageline($image, $x_last, $y_last, $x, $y, $color_graph);
		if ($point) imagefilledrectangle($image, $x-ceil($s/10), $y-ceil($s/10), $x+ceil($s/10), $y+ceil($s/10), $color_graph);
		if ($point_info){
			$font_size = $s/4;
			if ($font_size < 5) $font_size = 5;
			$text = '('.bcdiv($pts[$i-1], 1, 2).'; '.bcdiv($pts[$i], 1, 2).')';
			$font = imagettfbbox($font_size, 0, $graph_font, $text);
			imagettftext($image, $font_size, 0, $x+ceil($s/10)-1, $y+ceil($s/10)+($font[0]-$font[7]), $color_body, $graph_font, $text);
			imagettftext($image, $font_size, 0, $x+ceil($s/10)+1, $y+ceil($s/10)+($font[0]-$font[7]), $color_body, $graph_font, $text);
			imagettftext($image, $font_size, 0, $x+ceil($s/10), $y+ceil($s/10)+($font[0]-$font[7])+1, $color_body, $graph_font, $text);
			imagettftext($image, $font_size, 0, $x+ceil($s/10), $y+ceil($s/10)+($font[0]-$font[7])-1, $color_body, $graph_font, $text);
			
			imagettftext($image, $font_size, 0, $x+ceil($s/10), $y+ceil($s/10)+($font[0]-$font[7]), $color_text, $graph_font, $text);
		}
		$x_last = $x;
		$y_last = $y;
	}
	header("Content-type: image/gif");
	imagegif($image);
	imagedestroy($image);
}

?>