


PHP tree deep calendar generation maze and A* automatic pathfinding algorithm example analysis, maze example analysis_PHP tutorial
Example analysis of deep chronological maze generation of PHP trees and A* automatic pathfinding algorithm, maze example analysis
This article describes the deep chronological generation of mazes and A* of PHP trees through examples *Automatic pathfinding algorithm. Share it with everyone for your reference. The specific analysis is as follows:
A colleague recommended Sansi’s maze algorithm. After reading it, I thought it was pretty good, so I converted it to PHP
Sansi's maze algorithm uses the principle of tree depth traversal. The maze generated in this way is quite thin, and the number of dead ends is relatively small!
There is only one path between any two points.
As for the A* pathfinding algorithm, it is the most popular fully automatic pathfinding algorithm
No further nonsense, just paste the code
Maze generation class:
Copy code The code is as follows: class Maze{
// Maze Create
private $_w;
private $_h;
Private $_grids;
private $_walkHistory;
Private $_walkHistory2;
Private $_targetSteps;
// Construct
Public function Maze() {
$this->_w = 6;
$this->_h = 6;
$this->_grids = array();
}
//Set the maze size
Public function set($width = 6, $height = 6) {
If ( $width > 0 ) $this->_w = $width;
If ( $height > 0 ) $this->_h = $height;
return $this;
}
// Get the maze
Public function get() {
return $this->_grids;
}
// Generate maze
Public function create() {
$this->_init();
return $this->_walk(rand(0, count($this->_grids) -1 ));
}
// Get the dead end point
Public function block($n = 0, $rand = false) {
$l = count($this->_grids);
for( $i = 1; $i
$v = $this->_grids[$i];
If ( $v == 1 || $v == 2 || $v == 4 || $v == 8 ) {
$return[] = $i;
}
}
// Randomly pick points
if ( $rand ) shuffle($return);
if ( $n == 0 ) return $return;
if ( $n == 1 ) {
return array_pop($return);
} else {
return array_slice($return, 0, $n);
}
}
/**
|------------------------------------------------- ---------------
| | Series of functions to generate maze
|------------------------------------------------- ---------------
*/
Private function _walk($startPos) {
$this->_walkHistory = array();
$this->_walkHistory2 = array();
$curPos = $startPos;
while ($this->_getNext0() != -1) {
$curPos = $this->_step($curPos);
if ( $curPos === false ) break;
}
return $this;
}
Private function _getTargetSteps($curPos) {
$p = 0;
$a = array();
$p = $curPos - $this->_w;
If ($p > 0 && $this->_grids[$p] === 0 && ! $this->_isRepeating($p)) {
array_push($a, $p);
} else {
array_push($a, -1);
}
$p = $curPos + 1;
if ($p % $this->_w != 0 && $this->_grids[$p] === 0 && ! $this->_isRepeating($p)) {
array_push($a, $p);
} else {
array_push($a, -1);
}
$p = $curPos + $this->_w;
if ($p _grids) && $this->_grids[$p] === 0 && ! $this->_isRepeating($p)) {
array_push($a, $p);
} else {
array_push($a, -1);
}
$p = $curPos - 1;
if (($curPos % $this->_w) != 0 && $this->_grids[$p] === 0 && ! $this->_isRepeating($p)) {
array_push($a, $p);
} else {
array_push($a, -1);
}
return $a;
}
private function _noStep() {
$l = count($this->_targetSteps);
for ($i = 0; $i
if ($this->_targetSteps[$i] != -1) return false;
}
return true;
}
private function _step($curPos) {
$this->_targetSteps = $this->_getTargetSteps($curPos);
if ( $this->_noStep() ) {
if ( count($this->_walkHistory) > 0 ) {
$tmp = array_pop($this->_walkHistory);
} else {
return false;
}
array_push($this->_walkHistory2, $tmp);
return $this->_step($tmp);
}
$r = rand(0, 3);
while ( $this->_targetSteps[$r] == -1) {
$r = rand(0, 3);
}
$nextPos = $this->_targetSteps[$r];
$isCross = false;
if ( $this->_grids[$nextPos] != 0)
$isCross = true;
if ($r == 0) {
$this->_grids[$curPos] ^= 1;
$this->_grids[$nextPos] ^= 4;
} elseif ($r == 1) {
$this->_grids[$curPos] ^= 2;
$this->_grids[$nextPos] ^= 8;
} elseif ($r == 2) {
$this->_grids[$curPos] ^= 4;
$this->_grids[$nextPos] ^= 1;
} elseif ($r == 3) {
$this->_grids[$curPos] ^= 8;
$this->_grids[$nextPos] ^= 2;
}
array_push($this->_walkHistory, $curPos);
return $isCross ? false : $nextPos;
}
private function _isRepeating($p) {
$l = count($this->_walkHistory);
for ($i = 0; $i
if ($this->_walkHistory[$i] == $p) return true;
}
$l = count($this->_walkHistory2);
for ($i = 0; $i
if ($this->_walkHistory2[$i] == $p) return true;
}
return false;
}
private function _getNext0() {
$l = count($this->_grids);
for ($i = 0; $i
if ( $this->_grids[$i] == 0) return $i;
}
return -1;
}
private function _init() {
$this->_grids = array();
for ($y = 0; $y _h; $y ++) {
for ($x = 0; $x _w; $x ++) {
array_push($this->_grids, 0);
}
}
return $this;
}
}
A*寻路算法
复制代码 代码如下:class AStar{
// A-star
private $_open;
private $_closed;
private $_start;
private $_end;
private $_grids;
private $_w;
private $_h;
// Construct
public function AStar(){
$this->_w = null;
$this->_h = null;
$this->_grids = null;
}
public function set($width, $height, $grids) {
$this->_w = $width;
$this->_h = $height;
$this->_grids = $grids;
return $this;
}
// 迷宫中寻路
public function search($start = false, $end = false) {
return $this->_search($start, $end);
}
/**
|------------------------------------------------- ---------------
| Automatic path finding - A-star algorithm
|------------------------------------------------- ---------------
*/
public function _search($start = false, $end = false) {
if ( $start !== false ) $this->_start = $start;
if ( $end !== false ) $this->_end = $end;
$_sh = $this->_getH($start);
$point['i'] = $start;
$point['f'] = $_sh;
$point['g'] = 0;
$point['h'] = $_sh;
$point['p'] = null;
$this->_open[] = $point;
$this->_closed[$start] = $point;
while ( 0 _open) ) {
$minf = false;
foreach( $this->_open as $key => $maxNode ) {
if ( $minf === false || $minf > $maxNode['f'] ) {
$minIndex = $key;
}
}
$nowNode = $this->_open[$minIndex];
unset($this->_open[$minIndex]);
if ( $nowNode['i'] == $this->_end ) {
$tp = array();
while( $nowNode['p'] !== null ) {
array_unshift($tp, $nowNode['p']);
$nowNode = $this->_closed[$nowNode['p']];
}
array_push($tp, $this->_end);
break;
}
$this->_setPoint($nowNode['i']);
}
$this->_closed = array();
$this->_open = array();
return $tp;
}
private function _setPoint($me) {
$point = $this->_grids[$me];
// 所有可选方向入队列
if ( $point & 1 ) {
$next = $me - $this->_w;
$this->_checkPoint($me, $next);
}
if ( $point & 2 ) {
$next = $me + 1;
$this->_checkPoint($me, $next);
}
if ( $point & 4 ) {
$next = $me + $this->_w;
$this->_checkPoint($me, $next);
}
if ( $point & 8 ) {
$next = $me - 1;
$this->_checkPoint($me, $next);
}
}
private function _checkPoint($pNode, $next) {
if ( $this->_closed[$next] ) {
$_g = $this->_closed[$pNode]['g'] + $this->_getG($next);
if ( $_g
$this->_closed[$next]['g'] = $_g;
$this->_closed[$next]['f'] = $this->_closed[$next]['g'] + $this->_closed[$next]['h'];
$this->_closed[$next]['p'] = $pNode;
}
} else {
$point['p'] = $pNode;
$point['h'] = $this->_getH($next);
$point['g'] = $this->_getG($next);
$point['f'] = $point['h'] + $point['g'];
$point['i'] = $next;
$this->_open[] = $point;
$this->_closed[$next] = $point;
}
}
private function _getG($point) {
return abs($this->_start - $point);
}
private function _getH($point) {
return abs($this->_end - $point);
}
}
完整实例代码点击此处本站下载。
有需要大家可以直接下demo,看看效果!
希望本文所述对大家的php程序设计有所帮助。

TomodifydatainaPHPsession,startthesessionwithsession_start(),thenuse$_SESSIONtoset,modify,orremovevariables.1)Startthesession.2)Setormodifysessionvariablesusing$_SESSION.3)Removevariableswithunset().4)Clearallvariableswithsession_unset().5)Destroythe

Arrays can be stored in PHP sessions. 1. Start the session and use session_start(). 2. Create an array and store it in $_SESSION. 3. Retrieve the array through $_SESSION. 4. Optimize session data to improve performance.

PHP session garbage collection is triggered through a probability mechanism to clean up expired session data. 1) Set the trigger probability and session life cycle in the configuration file; 2) You can use cron tasks to optimize high-load applications; 3) You need to balance the garbage collection frequency and performance to avoid data loss.

Tracking user session activities in PHP is implemented through session management. 1) Use session_start() to start the session. 2) Store and access data through the $_SESSION array. 3) Call session_destroy() to end the session. Session tracking is used for user behavior analysis, security monitoring, and performance optimization.

Using databases to store PHP session data can improve performance and scalability. 1) Configure MySQL to store session data: Set up the session processor in php.ini or PHP code. 2) Implement custom session processor: define open, close, read, write and other functions to interact with the database. 3) Optimization and best practices: Use indexing, caching, data compression and distributed storage to improve performance.

PHPsessionstrackuserdataacrossmultiplepagerequestsusingauniqueIDstoredinacookie.Here'showtomanagethemeffectively:1)Startasessionwithsession_start()andstoredatain$_SESSION.2)RegeneratethesessionIDafterloginwithsession_regenerate_id(true)topreventsessi

In PHP, iterating through session data can be achieved through the following steps: 1. Start the session using session_start(). 2. Iterate through foreach loop through all key-value pairs in the $_SESSION array. 3. When processing complex data structures, use is_array() or is_object() functions and use print_r() to output detailed information. 4. When optimizing traversal, paging can be used to avoid processing large amounts of data at one time. This will help you manage and use PHP session data more efficiently in your actual project.

The session realizes user authentication through the server-side state management mechanism. 1) Session creation and generation of unique IDs, 2) IDs are passed through cookies, 3) Server stores and accesses session data through IDs, 4) User authentication and status management are realized, improving application security and user experience.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
