<?php
/**
*
* This file is part of the phpBB Forum Software package.
*
* @copyright (c) phpBB Limited <https://www.phpbb.com>
* @license GNU General Public License, version 2 (GPL-2.0)
*
* For full copyright and license information, please see
* the docs/CREDITS.txt file.
*
*/
namespace phpbb\captcha;
class char_cube3d
{
var $bitmap;
var $bitmap_width;
var $bitmap_height;
var $basis_matrix = array(array(1, 0, 0), array(0, 1, 0), array(0, 0, 1));
var $abs_x = array(1, 0);
var $abs_y = array(0, 1);
var $x = 0;
var $y = 1;
var $z = 2;
var $letter = '';
/**
*/
function __construct(&$bitmaps, $letter)
{
$this->bitmap = $bitmaps['data'][$letter];
$this->bitmap_width = $bitmaps['width'];
$this->bitmap_height = $bitmaps['height'];
$this->basis_matrix[0][0] = mt_rand(-600, 600);
$this->basis_matrix[0][1] = mt_rand(-600, 600);
$this->basis_matrix[0][2] = (mt_rand(0, 1) * 2000) - 1000;
$this->basis_matrix[1][0] = mt_rand(-1000, 1000);
$this->basis_matrix[1][1] = mt_rand(-1000, 1000);
$this->basis_matrix[1][2] = mt_rand(-1000, 1000);
$this->normalize($this->basis_matrix[0]);
$this->normalize($this->basis_matrix[1]);
$this->basis_matrix[2] = $this->cross_product($this->basis_matrix[0], $this->basis_matrix[1]);
$this->normalize($this->basis_matrix[2]);
// $this->basis_matrix[1] might not be (probably isn't) orthogonal to $basis_matrix[0]
$this->basis_matrix[1] = $this->cross_product($this->basis_matrix[0], $this->basis_matrix[2]);
$this->normalize($this->basis_matrix[1]);
// Make sure our cube is facing into the canvas (assuming +z == in)
for ($i = 0; $i < 3; ++$i)
{
if ($this->basis_matrix[$i][2] < 0)
{
$this->basis_matrix[$i][0] *= -1;
$this->basis_matrix[$i][1] *= -1;
$this->basis_matrix[$i][2] *= -1;
}
}
// Force our "z" basis vector to be the one with greatest absolute z value
$this->x = 0;
$this->y = 1;
$this->z = 2;
// Swap "y" with "z"
if ($this->basis_matrix[1][2] > $this->basis_matrix[2][2])
{
$this->z = 1;
$this->y = 2;
}
// Swap "x" with "z"
if ($this->basis_matrix[0][2] > $this->basis_matrix[$this->z][2])
{
$this->x = $this->z;
$this->z = 0;
}
// Still need to determine which of $x,$y are which.
// wrong orientation if y's y-component is less than it's x-component
// likewise if x's x-component is less than it's y-component
// if they disagree, go with the one with the greater weight difference.
// rotate if positive
$weight = (abs($this->basis_matrix[$this->x][1]) - abs($this->basis_matrix[$this->x][0])) + (abs($this->basis_matrix[$this->y][0]) - abs($this->basis_matrix[$this->y][1]));
// Swap "x" with "y"
if ($weight > 0)
{
list($this->x, $this->y) = array($this->y, $this->x);
}
$this->abs_x = array($this->basis_matrix[$this->x][0], $this->basis_matrix[$this->x][1]);
$this->abs_y = array($this->basis_matrix[$this->y][0], $this->basis_matrix[$this->y][1]);
if ($this->abs_x[0] < 0)
{
$this->abs_x[0] *= -1;
$this->abs_x[1] *= -1;
}
if ($this->abs_y[1] > 0)
{
$this->abs_y[0] *= -1;
$this->abs_y[1] *= -1;
}
$this->letter = $letter;
}
/**
* Draw a character
*/
function drawchar($scale, $xoff, $yoff, $img, $background, $colours)
{
$width = $this->bitmap_width;
$height = $this->bitmap_height;
$bitmap = $this->bitmap;
$colour1 = $colours[array_rand($colours)];
$colour2 = $colours[array_rand($colours)];
$swapx = ($this->basis_matrix[$this->x][0] > 0);
$swapy = ($this->basis_matrix[$this->y][1] < 0);
for ($y = 0; $y < $height; ++$y)
{
for ($x = 0; $x < $width; ++$x)
{
$xp = ($swapx) ? ($width - $x - 1) : $x;
$yp = ($swapy) ? ($height - $y - 1) : $y;
if ($bitmap[$height - $yp - 1][$xp])
{
$dx = $this->scale($this->abs_x, ($xp - ($swapx ? ($width / 2) : ($width / 2) - 1)) * $scale);
$dy = $this->scale($this->abs_y, ($yp - ($swapy ? ($height / 2) : ($height / 2) - 1)) * $scale);
$xo = $xoff + $dx[0] + $dy[0];
$yo = $yoff + $dx[1] + $dy[1];
$origin = array(0, 0, 0);
$xvec = $this->scale($this->basis_matrix[$this->x], $scale);
$yvec = $this->scale($this->basis_matrix[$this->y], $scale);
$face_corner = $this->sum2($xvec, $yvec);
$zvec = $this->scale($this->basis_matrix[$this->z], $scale);
$x_corner = $this->sum2($xvec, $zvec);
$y_corner = $this->sum2($yvec, $zvec);
imagefilledpolygon($img, $this->gen_poly($xo, $yo, $origin, $xvec, $x_corner,$zvec), 4, $colour1);
imagefilledpolygon($img, $this->gen_poly($xo, $yo, $origin, $yvec, $y_corner,$zvec), 4, $colour2);
$face = $this->gen_poly($xo, $yo, $origin, $xvec, $face_corner, $yvec);
imagefilledpolygon($img, $face, 4, $background);
imagepolygon($img, $face, 4, $colour1);
}
}
}
}
/*
* return a roughly acceptable range of sizes for rendering with this texttype
*/
function range()
{
return array(3, 4);
}
/**
* Vector length
*/
function vectorlen($vector)
{
return sqrt(pow($vector[0], 2) + pow($vector[1], 2) + pow($vector[2], 2));
}
/**
* Normalize
*/
function normalize(&$vector, $length = 1)
{
$length = (( $length < 1) ? 1 : $length);
$length /= $this->vectorlen($vector);
$vector[0] *= $length;
$vector[1] *= $length;
$vector[2] *= $length;
}
/**
*/
function cross_product($vector1, $vector2)
{
$retval = array(0, 0, 0);
$retval[0] = (($vector1[1] * $vector2[2]) - ($vector1[2] * $vector2[1]));
$retval[1] = -(($vector1[0] * $vector2[2]) - ($vector1[2] * $vector2[0]));
$retval[2] = (($vector1[0] * $vector2[1]) - ($vector1[1] * $vector2[0]));
return $retval;
}
/**
*/
function sum($vector1, $vector2)
{
return array($vector1[0] + $vector2[0], $vector1[1] + $vector2[1], $vector1[2] + $vector2[2]);
}
/**
*/
function sum2($vector1, $vector2)
{
return array($vector1[0] + $vector2[0], $vector1[1] + $vector2[1]);
}
/**
*/
function scale($vector, $length)
{
if (count($vector) == 2)
{
return array($vector[0] * $length, $vector[1] * $length);
}
return array($vector[0] * $length, $vector[1] * $length, $vector[2] * $length);
}
/**
*/
function gen_poly($xoff, $yoff, &$vec1, &$vec2, &$vec3, &$vec4)
{
$poly = array();
$poly[0] = $xoff + $vec1[0];
$poly[1] = $yoff + $vec1[1];
$poly[2] = $xoff + $vec2[0];
$poly[3] = $yoff + $vec2[1];
$poly[4] = $xoff + $vec3[0];
$poly[5] = $yoff + $vec3[1];
$poly[6] = $xoff + $vec4[0];
$poly[7] = $yoff + $vec4[1];
return $poly;
}
/**
* dimensions
*/
function dimensions($size)
{
$xn = $this->scale($this->basis_matrix[$this->x], -($this->bitmap_width / 2) * $size);
$xp = $this->scale($this->basis_matrix[$this->x], ($this->bitmap_width / 2) * $size);
$yn = $this->scale($this->basis_matrix[$this->y], -($this->bitmap_height / 2) * $size);
$yp = $this->scale($this->basis_matrix[$this->y], ($this->bitmap_height / 2) * $size);
$p = array();
$p[0] = $this->sum2($xn, $yn);
$p[1] = $this->sum2($xp, $yn);
$p[2] = $this->sum2($xp, $yp);
$p[3] = $this->sum2($xn, $yp);
$min_x = $max_x = $p[0][0];
$min_y = $max_y = $p[0][1];
for ($i = 1; $i < 4; ++$i)
{
$min_x = ($min_x > $p[$i][0]) ? $p[$i][0] : $min_x;
$min_y = ($min_y > $p[$i][1]) ? $p[$i][1] : $min_y;
$max_x = ($max_x < $p[$i][0]) ? $p[$i][0] : $max_x;
$max_y = ($max_y < $p[$i][1]) ? $p[$i][1] : $max_y;
}
return array($min_x, $min_y, $max_x, $max_y);
}
}