draw_arc in counterclockwise?

newguy

Hi, is there a way to perform draw_arc in counterclockwise?

Like in HTML canvas arc() Method there is a parameter to specify counterclockwise. https://www.w3schools.com/tags/canvas_arc.asp

DaveTheCoder

Why do you need to do that?

newguy

@DaveTheCoder said: Why do you need to do that?

I am converting some html5 code to godot. I have this code in html which is supposed to draw an arc starting at the right side. ctx.arc(0, 0, 92, 0.3*Math.PI, 1.7*Math.PI, true); // the last parameter is to enable draw in counterclockwise

Same code in godot the arc will draw to the left side.

cybereality

You are drawing between one point and another point. It doesn't really matter which way it goes. Like if you draw a single straight line, it makes no difference whether you draw left to right or right to left, in the end you have the same exact line.

newguy

@cybereality said: You are drawing between one point and another point. It doesn't really matter which way it goes. Like if you draw a single straight line, it makes no difference whether you draw left to right or right to left, in the end you have the same exact line.

It made a difference. Please refer to attached image. In html the arc was drawn at right side while in godot it was drawn at left side. I need to draw the arc at right side.

DaveTheCoder

You simply need to adjust the values for start_angle and end_angle.

Also note that in Godot, angles are measured clockwise from the positive X-axis, which is to the right. I don't know how angles are measured in HTML.

Try using the values -0.3 PI and 0.3 PI for start_angle and end_angle.

Angle visualizer: http://beinoni.org/godot/angles/

cybereality

You can look at the docs for how to draw an arc. You set the starting and ending angles yourself. In the image you posted, it may just be a matter of switching the parameters. https://docs.godotengine.org/en/stable/classes/class_canvasitem.html#class-canvasitem-method-draw-arc

newguy

@DaveTheCoder said: You simply need to adjust the values for start_angle and end_angle.

Also note that in Godot, angles are measured clockwise from the positive X-axis, which is to the right. I don't know how angles are measured in HTML.

Try using the values -0.3 PI and 0.3 PI for start_angle and end_angle.

Angle visualizer: http://beinoni.org/godot/angles/

Yes, that work. Thanks!

DaveTheCoder

Switching the parameters (1.7 PI and 0.3 PI for start_angle and end_angle), as cybereality suggested, would probably work too.