Construction in GCLC language

dim 120 120

point B 20 40
point O 65 51.14
point I 74.37 61.15

color 220 0 0
fontsize 11

cmark_b B
cmark_t O
cmark_b I
color 0 0 0
fontsize 10

% DET:  points B and I are not the same
% Constructing a line s_{b} which passes through point B and point I
line s_{b} B I 

color 200 200 200
drawline s_{b}
color 0 0 0



% NDG:  points B and O are not the same
% Constructing a circle k(O,C) whose center is at point O and which passes through point B
circle k(O,C) O B 

color 200 200 200
drawcircle k(O,C)
color 0 0 0



% NDG:  line s_{b} and circle k(O,C) intersect% DET:  points B and N_{b} must be different
% Constructing a point P_{\_G23794} which is a foot of the point O on the line s_{b}
foot P_{\_G23794} O s_{b} 
cmark_r P_{\_G23794}
color 200 200 200
drawline O P_{\_G23794} 
color 0 0 0

% Constructing a point N_{b} which is an image of the point B in the symmetry to point/line P_{\_G23794}
sim N_{b} P_{\_G23794} B 
cmark_rb N_{b}


% NDG:  points I and N_{b} are not the same
% Constructing a circle k(N_{b},A) whose center is at point N_{b} and which passes through point I
circle k(N_{b},A) N_{b} I 

color 200 200 200
drawcircle k(N_{b},A)
color 0 0 0



% NDG:  circles k(O,C) and k(N_{b},A) intersect% DET:  circles k(O,C) and k(N_{b},A) are not the same
% Constructing points C and A which are in intersection of k(O,C) and k(N_{b},A)
intersec2 C A k(O,C) k(N_{b},A) 
cmark_b C
cmark_t A



drawsegment A B
drawsegment A C
drawsegment B C

% Non-degenerate conditions:  circles k(O,C) and k(N_{b},A) intersect; points I and N_{b} are not the same; line s_{b} and circle k(O,C) intersect; points B and O are not the same
% Determination conditions:  circles k(O,C) and k(N_{b},A) are not the same; points B and N_{b} must be different; points B and I are not the same