The coloring functions of WINDEV are based on the encapsulation of the ExtFoodFill (dFill) and GetPixel (dPixelColor) APIs
that use 24-bit RGB colors that do not support the alpha channel, so it is not possible to create transparent areas.

To work around this limitation, here is a project that illustrates the clipping functions of GDImage64.
The principle is the same as in PhotoShop, a checkerboard is used in the background to visualize the transparent areas.
All fill and pixel selection functions work in 32-bit mode (with alpha channel).
When filling it is possible to use a tolerance factor, which allows to remove the artifacts caused by the jpeg compression.
Note: Cropped images must be saved in PNG format to preserve transparency.

About the interface:
This is entirely done with 2 GDImage fields, one for the work area (with the image),
the other containing the controls:
- The color selector, which allows you to use either a color picker or a combo box to choose the desired color.
- 2 vertical sliders, one to choose the level of transparency, the other for the filling tolerance.
- Several icons to choose or save an image, or cancel the modifications.
- Information concerning the coordinates of the cursor, as well as the color of the pixel flown over with its components A, R, G, B.

The project works with all the WINDEV versions from WD17 +
WINDEV must be set in 64-BIT MODE