GRAPHREP

SET x_param:1cm 

SET y_param:1cm

FILL color:lightblue

RECTANGLE x:c y:c w:(0.5*x_param) h:(0.25*y_param)

POLYGON 4 x1:(0.5*x_param) y1:(0.25*y_param)

          x2:(0.62*x_param) y2:(0.125*y_param)

          x3:(0.625*x_param) y3:(-0.125*y_param)

          x4:(0.5*x_param) y4:0

POLYGON 4 x1:0cm y1:0

          x2:(0.125*x_param) y2:(-0.125*y_param)

          x3:(0.625*x_param) y3:(-0.125*y_param)

          x4:(0.5*x_param) y4:0

ATTR "Location name" w:c:(3*x_param) y:(0.4*y_param) line-break:rigorous