Jeyapalan, Kandiah 
  
VIRTUAL REALITY 
Virtual reality is the mode in which a user can view in 3 dimension, fly through the virtual model, modify in real time 
and view or measure its effect. 
  
| PLOTTING DF DETAILS FRUM SDFTPLDTTER MEASUREMENTS USING 
  
  
+ oO B 
  
  
  
  
  
  
  
  
Dwipen Bhogowati 
  
  
  
  
Doted 4/10/97 
  
Fig 14. Soft Photogrammetric Map Fig 15. Multi Direction 
In soft photogrammetry one view in 3D where the image is displayed, in front, on the computer screen similar to a 
mirror except it is a real image and not an inverted mirror image. In virtual reality one could view in all direction see 
fig 16 or in any one direction see fig 17. And by having the sense of touch the model can be instantaneously changed 
and viewed. 
In order to accomplish the virtual reality the 3D view is diplayed in one to six directions using one to six computers, fig 
17, and the displays are controlled by hand held control which in turn controls the computer display, see Fig 15. This is 
done by knowing the 3D coordinates of every pixel of the object as well as its texture. From the hand held control the 
camera location and orientaion, X,, Y, , Z,, «, «, c, for each camera are changed and the photo coordinates, p,, ps ». for 
every pixel for both cameras are computed using equation(1) and displayed with its texture instantaneously see fig 15. 
   
Fig 16. Unidirection Fig 17. Virtual Display 
Soft Photogrammetry can be used to determine the 3D coordinates of every pixel in the image of the object captured by 
metric camera, digital camera, video camera etc. In practise the geometry of the object can be visualized using the TIN 
(Triangular irregular network) of points whose 3D coordinates are determined by soft photogrammetry and the texture 
by remote sensing. 
  
412 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000.