Parameters of 3D Images

Figure D.1: Parameters of 3D Images

The functions of OpenGL Library used during 3D image reconstruction. The parameters of 3D images use the parameters (fig. D.1) included in the lighting equation of this Library of the following type:

$$L=I^M_E+R^M_A\cdot I^S_A+\sum^n_{i=1}{(R^M_A\cdot I^{L_i}_A+R... ...{L_i}_S\cdot (\overline{N}_V\cdot \overline{N}_{L_i})^{Sh^M})}$$

where

• $I^M_E$ - Intensity of material emission (Mat. Emission).
• $R^M_A$ - material color for diffused light (Mat. Color).
• $R^M_D$ - material reflection color for directed light (Mat. Color).
• $R^M_S$ - material reflection color for reflected light (Mat. Specular)
• $I^S_A$ - scene ambient intensity (Scene Ambient)
• $n$ - number of light sources (in our case - 1, if the illumination is switched on, and 0, if switched off) is selected using Menu Command View/ Hilighted)
• $I^{L_i}_A$ - intensity of diffused light (Light Ambient)
• $I^{L_i}_D$ - intensity of directed light (Light Diffuse)
• $I^{L_i}_S$ - intensity of reflected light (Light Specular)
• $\overline{N}$ - vector normal to the surface
• $\overline{N}_{L_i}$ - vector directed from the surface point to the light source
• $\overline{N}_V$ - vector directed from the surface point to the observer
• $Sh^M$ - Material Shininess)

In our case we use the model, where $R^M_A=R^M_D$, and this parameter is called Material Color. If the mark Use single color material is selected in tab General then the color will be taken from option Material Color, otherwise - from the current palette according to the height of the point.

R, G and B component of each parameter may be defined using the scroll bars or a color selection dialogue. This dialogue appears by pressing Left Button of the Mouse in the color rectangular, place din the right part of the corresponding tab.

The current parameters may be stored into the file with extension .3dopt. The parameters may be read from the file or default parameters can be selected.