Draw Triangle

This function draws a triangle at point (x1,y1) to point (x2,y2) and to point (x3,y3).
The "Outline" argument indicates if the triangle is filled (0) or lined (1).

To change the color used for drawing, use the function draw_set_color().

draw_triangle(x1,y1,x2,y2,x3,y3,outline)