However, since I am new to labview, I am not able to understand how they have done this or which tool is used here.
I have the equations that show the light energy reaching each point in a 2d object. The light is exposed multiple times. So, the software needs to calculate the sum of energy for all exposures and show the result as a 2d image with colours indicating the total energy.
I have not read the paper, but for 3D printing you have a volume, probably approximated by a 3D array. (This can get memory intensive!). Keep that 3D array in a shift register and sum all projections. ("nearest" interpolation is probably sufficient).
Of course you can simplify it by only doing a single plane, which would give you a 2D image of "counts".
(Decades ago, one of the LabVIEW shipping examples was a tomography simulation that did a similar thing)