tasks:
1=mental mapping
3=distance estimation
4=point-wise value estimation
5=area-wise value estimation

rendering techniques:
0=none
1=blinn-phong shading
2=SSAO
3=edge enhancement (EE)
4=abstracted facade textures (AFT)
5=blinn-phong + SSAO
6=SSAO+AFT
7=AFT+EE

color mapping:
0=single hue white-red
1=black body radiation
2=diverging blue-white-red

is training: whether the trial is a training trial (was not considered in the evaluation)

value user: value entered by the user
value ref: correct value
mouse_x_user, mouse_y_user: clicked coordinates
mouse_x_ref, mouse_y_ref: correct coordinates