Appearance
Rectangle / Ellipse
Use geometric tools to draw rectangle and ellipse shapes.
Usage
Select the rectangle tool, click and drag the mouse on the image to draw a rectangle.
Toolbar

- Line Type, you can choose solid line, dashed line, dotted line, etc. (Solid shapes are not supported)
- Hollow Shape Brush Thickness, after selecting, you can draw hollow shapes. Use the mouse wheel to adjust the brush size. Click again to switch to solid shapes.
- Solid Shape, after selecting, you can draw solid shapes. Click again to switch to hollow shapes.
- Rectangle, after selecting, you can draw rectangles.
- Ellipse, after selecting, you can draw ellipses.
- Color Palette, set the color of the shape. Click the largest color block to open the color picker for custom colors.
Draw Square / Circle
Hold down the Shift key while drawing a rectangle or ellipse to draw a square or circle.
Rotate
When the rectangle/ellipse is focused, move the mouse to the border surrounding the rectangle, and a rotation icon will appear. Hold down the left mouse button to rotate the rectangle/ellipse. 
Rounded Corner
The four corners of the rectangle annotation have rounded corner control points. Hold and move to adjust the rounded corner size. 
Sector
The ellipse annotation has a control point inside the circle. Hold and move to adjust it to a sector. 
Arc
There is a control point in the center of the sector. Hold and move to adjust it to an arc. 
Re-adjust
After drawing the shape, re-adjustment is supported. You can hold the control points on the shape to adjust, or hold the shape after selecting it to drag and adjust the position.
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