Protractor or Triangle Tool

Is there a protactor or Triangle Tool in CSP? Or a specific tool which you can calculate the degrees of an angle of a shape ? That would be really useful cause i need it frequently.
Thank you so much.

Create an ellipse ruler with a scale on it (mm, Q, px or whatever). Make the figure draw from the center and hold SHIFT to make a circle. Click on your corner and drag out the circle. Now select the Object tool. Change the scale units to something that works for the size you need; ie. px for something small, mm for something larger. Grab the rotate handle and turn the ellipse so 0 in on the line. Then click a corner handle and then click and hold ALT and SHIFT while scaling the ellipse until 360 is overtaken by the 0. Boom  protractor.
Then you could zoom in and see the exact angle.

@garlam It doesn't look works right cause I think a degree is a different unit from p.x.,mm, etc.

Here what I try to do, maybe this will help you to understand what I need.
Here is a two point perspective PERFECT square.
To do this you need to find the third vanishing point (this is between the two others). So to find it you need to connect two lines from the right and the left vanishing points and then to find the 90 degrees angle of the connected lines, I draw square with a 45 degrees line which connects the two corners of the square
here the example
So what I do is, to rotate this square and scale up until it touch/sit/crossover with both vanishing points (Left and Right) and touch to the angle which I want to create the perfect square like this image
And the middle line intersect with the horizontal line is the spot of the third vanishing point.
I hope that you understand how I work and what i want to tell you, it's really complicated so I hope that there is a solution.
Thank you very much.

A circle is made up of 360 degrees. As long as there are 360 divisions, you can find the angle regardless of whether you use px, mm, Q or whatever.
The angles in your square are 90, 70, 145, 55. That adds up to 360 degrees.
The angles of the red dot corners are 35, 90, 55. That equals 180. And the angles of the blue dot corners are 20, 70, and 90. Also equals 180. The math all works out.