PN G
This professional-grade solution for MetaTrader 5 helps traders achieve greater efficiency in their daily workflow. This library provides a collection of modular, reusable code. It is utilized by developers to organize common functions, allowing for the integration of complex logic across multiple Expert Advisors, indicators, or scripts without the need for code duplication.
How to Setup and Use PN G
1. Storage: Place library files in the MQL/Libraries directory to ensure they are accessible to your projects.
2. Implementation: Include the library in your code using the #import directive, ensuring you match the exact function names and parameters.
3. Compilation: Ensure the library is present in the directory before you compile your main EA or script, as the compiler links them during this phase.
4. Management: Keep libraries organized in sub-folders if you manage many custom functions to maintain a clean project structure.
Frequently Asked Questions
Q: What is a library file used for? A: Libraries store reusable code modules, allowing you to centralize common logic used by multiple EAs or indicators.
Q: Is a library executable? A: No, libraries are non-executable files containing functions; they must be imported into an EA, indicator, or script to function.
Q: Can I update a library while the platform is running? A: You should compile your EA or script after updating a library to ensure the latest code changes are integrated.
Description & Settings
This library allows you to comfortably work with PNG graphic files, as well as scale them.
There are two ways to upload PNG images:
via file
via a resource that is inside your ex5 file
Working with PNG images via resource:
Working with PNG images via file:
As you can see, it is possible to immediately form a canvas and display the image on the screen. And you can also be satisfied with just creating a bmp[] bitmap array without creating a canvas object for this image. In this case, you can use this array in more advanced implementations with your own canvases (see the demo below).
Further, an important function of this CPng class is the ability to generate a new image size using the Resize(double NewWidth) method, which will be located in the _bmp[] array, which can also be displayed on the screen, forming a canvas of this size.
In this case, the class instance will contain two bmp[] arrays (original image) with width "width" and height "height", as well as a resized _bmp[] array (width "_width" and height "_height"). All methods and parameters in the CPng class with an underscore at the beginning of the name refer to the resized image (_bmp[], _width, _height, _CreateCanvas(), _MoveCanvas())
The following functions are also available for working with original and modified images:
I have prepared a demo program-expert (Expert_Test_PNG.mq5), which compactly and visually demonstrates the work of this library. In this example, in addition to simply displaying PNG images, parsing of a table of PNG icons is implemented. (see gif animation)
I saw the implementation of this algorithm for decompressing PNG files from in this 7 years ago, which was taken as the basis of this library. The resize algorithm is my development.
