From Xojo Documentation
Rotates the drawing context by the specified angle (in radians) around the origin point (usually 0,0). This only affects subsequent drawing. Any drawing done before the Rotate method call is not rotated.
Rotates the drawing context at the x and y coordinates by the specified angle (in radians). This only affects subsequent drawing. Any drawing done before the Rotate method called is not rotated.
Use Translate to move the origin.
Support for Rotate in Desktop and Console applications was added in 2021r1.
From within an MobileCanvas.Paint event handler:
Const Pi = 3.14159
g.Translate(g.Width / 2, g.Height / 2)
g.Rotate(Pi / 4) // 45 degrees or 1/8 of a circle
g.DrawingColor = Color.Blue
g.FillRectangle(10, 10, 50, 50)