The photodissociation of molecules is becoming an increasingly important factor to consider in the evolution of exoplanets' atmospheres orbiting around UV-rich stars, as it leads to the enrichment of atmospheric complexity. A new method is developed for computing the rotationally and vibrationally resolved photodissociation spectrum of triatomic molecules. The time-independent Schrödinger equation is solved using the variational nuclear motion program EVEREST; a new code EXOCSMOOTH is employed to compute the cross-sections by applying Gaussian smoothing to a set of discrete transitions into the continuum. HCN is chosen as the test molecule, as it has been widely studied in the literature. Results are compared with the available experiments. Temperature dependence is explored for temperatures up to 2000 K.