Author Topic: draw a triangle.. (Read 2136 times)

Kocoo · « **on:** April 24, 2011, 08:41:47 pm »

Hello...

for a school project, i have to make a program that draws a triangle..
as input you insert the lenght of a,b and c sides..

I don't know to get the 3 corners out of the lenght of the sides...

Any help ?

Fred_FS · « **Reply #1 on:** April 25, 2011, 12:20:54 am »

I would set point A to (0|0). Point B is set at B(c|0)(c is opposite of point C. a opposite of A aHence the line between A and B. Now you have to find C. C is the intersection of a circle around point A with radius b and a circle around point B with radius a. So I would just step through all the points of a circle around point A with radius b and would check, wether the distance between this new point and B equals to line a.

To find all these points on a circle I would use:
x = center_x + r * cos phi
y = center_y + r * sin phi

Kocoo · « **Reply #2 on:** April 25, 2011, 10:05:00 am »

Ok thx..

Just, which points are center_x and center_y ?

Fred_FS · « **Reply #3 on:** April 25, 2011, 07:47:55 pm »

Every circle has a center. So center_x is the x value of your center and center_y is your y value

.
In your case it would be a circle around point A. So center_x is 0 and center_y is 0, too

.