Question

(a) Discuss how to draw a circle on a Canvas in JavaFX using low-level rendering techniques. [05] In your discussion incude what objects, methods, and parameters need to be used in the correct order. Please note: Do not provide code.

Answer 1

In JavaFX, to draw a circle using canvas,

1) Create a canvas first by using "Canvas Class"

Canvas class basically creates an image that can be drawn on using a set of graphics commands provided by a GraphicsContext.

To do that, use:

Canvas (double w, double h) - This creates a canvas object with w as width and h as height.

2) Then extract the GraphicsContext using getGraphicsContext2D() function

3) Finally, draw the circle by using

getGraphicsContext2D().strokeOval(center.x-radius, center.y-radius, radius, radius);

Here in parameter pass the x and y radius of the circle.