Visualization

We have implemented a simple visualization of the results in order to view images of the emitted intensities. The visualization uses IDL to read the results of the 3D RT code, performs a formal solution for a specific $(\theta,\phi)$ and displays the result as an image of the intensities leaving the voxel grid. These figures are extremely helpful for discovering even small problems with the generation and handling of the characteristics or issues due to low resolution in solid angle or space. Such problems will immediately show up as asymmetries in the generated images. We show the results for the LTE test (with $65^3$ voxels) in Fig. 14. The limb darkening of the test sphere is clearly visible in the figures. The slight pixellation and asymmetries are due to spatial and angular resolution. Note that the scales of the different panels are different due to the changing orientation of the data cube. The generated images for the $\epsilon =10^{-4}$ test case with $129^3$ and $193^3$ voxels are shown in Figs. 15 and 16, respectively. For both figures, the source functions were calculated with $64^2$ angles. The images show much less pixellation and far less artifacts than the images shown in Fig. 14. The results for the $\epsilon =10^{-8}$ test case are shown in Fig. 17, they look similar to the $\epsilon =10^{-4}$ case with the same grid sizes.