Introduction - If you have any usage issues, please Google them yourself
How to make graphical software development procedures, drawing process display, image layered display
Layer software architecture:
The general architecture of large graphics software is to classify and manage different layers of code using a polymorphic class derived from an abstract class (CLayer).
(if the various graphic drawing and drag and drop processes are written in a class, the code for that class will be extremely large and difficult to maintain)
A) software that supports graphics such as straight lines, rectangles, and ellipses. It must combine the mouse, press, release, and drag events together;
B) support display in drawing process;
C) displays the hot spot tracking (HotTrack) state when the mouse cursor is passed over a layer;
D) displays a selected state when clicked on a layer;
E) drag the function of a selected layer (offset by the distance between the mouse and the starting point);
F) the new layer and the selected layer border and fill color management.