Code is being tested against PHP versions 7.0 to 8.0
PHP version 8.1 brings breaking changes to imagefilledpolygon and count
for this reason I will create a separate repo for it.

pChart 2.1 library for PHP 7 (7-Compatible branch)

The good old pChart got an overhaul!

• All examples work fine with zero code modifications to them
• Code was beautified
• Made minor improvements and added some speed ups

pChart 2.2

This version will NOT work with your existing code, but supports PHP 7.0 & 7.1
Please check the change log for the complete list of changes.

Major changes:

• Code cleanup
• Bootstrapped
• Exceptions
• Introduced pColor & pColorGradient
• Moved functions around
• Added support for compression and filters in PNG output
• Cache: added PDO SQLite storage option
• ImageMapper: JavaScript re-write using jQuery
• ImageMapper: added PDO SQLite storage option
• Removed DelayedLoader

pChart 2.3 (recommended)

Goals:

• Reduce the use of the hard disk to fonts only
• Eliminate not-exactly-free 3rd party components
• Add the first batch of new features since 2011

Major changes:

• PHP 7.2+ required from now on
• Introduce pQRCode /* Check my PHP-QRCode-fork repo */
• Replace all fonts with Open Font licensed ones
• Performace boost
• pBarcode to own dir
• No more config files (palettes & barcode db)

pChart 2.4 (in progress)

Goals:

• Introduce pPyramid

Major changes:

• Removed pImageMap, pCache, pBarcode
• Introduced the new Barcodes lib /* Check out my PHP-Barcodes-fork repo */
• Introduced the new PDF417 lib /* Check out my PHP-PDF417-fork repo */
• Introduced the new Aztec lib /* Check out my PHP-Aztec-fork repo */
• Introduced the new QRCode lib /* Check out my PHP-QRCode-fork repo */
• Explicitly declare the visibility for methods and properties