C # redim of drawing tools

The move of the graphic element was mentioned in the previous article. This article describes the redim of the Graphic Element. Generally, the drawing software knows that multiple control points will appear after a graphic element is selected, when the mouse moves to these control points, it will automatically change the shape of the mouse, so that you can clearly understand the effect of dragging these control points. Similarly, in this redim function, multiple control points are added to the graphic element, for example, two control points are added to a straight line, eight control points are added to the rectangle (the rectangle is not rotated for the time being and will be displayed in the next way together with the saving of the file). First, let's take a look at these effects.

In fact, when the mouse is placed on the control point, the mouse state is automatically changed, but this effect is not displayed.

In the figure, you can see that the chart state can be changed by dragging the mouse. At the same time, you can clearly see the control point at the endpoint of the Graphic Element. Of course, if you want the control point to be more obvious, you can set the control point size by yourself. At the same time, when you move the mouse to the control point, you must be able to automatically change its shape. For example, if you move the mouse to this position for the control point at the starting point of a straight line, it should be automatically changed to cursors. sizenwse, You can visually remind the user that this is the control point, drag the mouse to change the element form. This tool is just a normal exercise and is not a real project. Therefore, many things are not considerate and will be gradually improved and expanded in the future.