TimeTrex/classes/misc/signature_to_image.class.php

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2022-12-13 07:10:06 +01:00
<?php
/**
* Signature to Image: A supplemental script for Signature Pad that
* generates an image of the signatures JSON output server-side using PHP.
*
* @project ca.thomasjbradley.applications.signaturetoimage
* @author Thomas J Bradley <hey@thomasjbradley.ca>
* @link http://thomasjbradley.ca/lab/signature-to-image
* @link http://github.com/thomasjbradley/signature-to-image
* @copyright Copyright MMXI, Thomas J Bradley
* @license New BSD License
* @version 1.0.1
*/
/**
* Accepts a signature created by signature pad in Json format
* Converts it to an image resource
* The image resource can then be changed into png, jpg whatever PHP GD supports
*
* To create a nicely anti-aliased graphic the signature is drawn 12 times it's original size then shrunken
*
* @param string|array $json
* @param array $options OPTIONAL; the options for image creation
* imageSize => array(width, height)
* bgColour => array(red, green, blue)
* penWidth => int
* penColour => array(red, green, blue)
*
* @return object
*/
function sigJsonToImage($json, $options = array())
{
$defaultOptions = array(
'imageSize' => array(198, 55)
,'bgColour' => array(0xff, 0xff, 0xff)
,'penWidth' => 2
,'penColour' => array(0x14, 0x53, 0x94)
,'drawMultiplier'=> 12
);
$options = array_merge($defaultOptions, $options);
$img = imagecreatetruecolor($options['imageSize'][0] * $options['drawMultiplier'], $options['imageSize'][1] * $options['drawMultiplier']);
$bg = imagecolorallocate($img, $options['bgColour'][0], $options['bgColour'][1], $options['bgColour'][2]);
$pen = imagecolorallocate($img, $options['penColour'][0], $options['penColour'][1], $options['penColour'][2]);
imagefill($img, 0, 0, $bg);
if(is_string($json))
$json = json_decode(stripslashes($json));
foreach($json as $v)
drawThickLine($img, $v->lx * $options['drawMultiplier'], $v->ly * $options['drawMultiplier'], $v->mx * $options['drawMultiplier'], $v->my * $options['drawMultiplier'], $pen, $options['penWidth'] * ($options['drawMultiplier'] / 2));
$imgDest = imagecreatetruecolor($options['imageSize'][0], $options['imageSize'][1]);
imagecopyresampled($imgDest, $img, 0, 0, 0, 0, $options['imageSize'][0], $options['imageSize'][0], $options['imageSize'][0] * $options['drawMultiplier'], $options['imageSize'][0] * $options['drawMultiplier']);
imagedestroy($img);
return $imgDest;
}
/**
* Draws a thick line
* Changing the thickness of a line using imagesetthickness doesn't produce as nice of result
*
* @param object $img
* @param int $startX
* @param int $startY
* @param int $endX
* @param int $endY
* @param object $colour
* @param int $thickness
*
* @return void
*/
function drawThickLine($img, $startX, $startY, $endX, $endY, $colour, $thickness)
{
$angle = (atan2(($startY - $endY), ($endX - $startX)));
$dist_x = $thickness * (sin($angle));
$dist_y = $thickness * (cos($angle));
$p1x = ceil(($startX + $dist_x));
$p1y = ceil(($startY + $dist_y));
$p2x = ceil(($endX + $dist_x));
$p2y = ceil(($endY + $dist_y));
$p3x = ceil(($endX - $dist_x));
$p3y = ceil(($endY - $dist_y));
$p4x = ceil(($startX - $dist_x));
$p4y = ceil(($startY - $dist_y));
$array = array(0=>$p1x, $p1y, $p2x, $p2y, $p3x, $p3y, $p4x, $p4y);
imagefilledpolygon($img, $array, (count($array)/2), $colour);
}