fix for fast particles moving through VOID

src/simulation/Simulation.cpp

@@ -4364,7 +4364,10 @@ void Simulation::update_particles_i(int start, int inc)
 						clear_y = (int)(clear_yf+0.5f);
 						break;
 					}
-					if (!eval_move(t, fin_x, fin_y, NULL) || (t == PT_PHOT && pmap[fin_y][fin_x]) || bmap[fin_y/CELL][fin_x/CELL]==WL_DESTROYALL)
+					//block if particle can't move (0), or some special cases where it returns 1 (can_move = 3 but returns 1 meaning particle will be eaten)
+					//also photons are still blocked (slowed down) by any particle (even ones it can move through), and absorb wall also blocks particles
+					int eval = eval_move(t, fin_x, fin_y, NULL);
+					if (!eval || (can_move[t][pmap[fin_y][fin_x]&0xFF] == 3 && eval == 1) || (t == PT_PHOT && pmap[fin_y][fin_x]) || bmap[fin_y/CELL][fin_x/CELL]==WL_DESTROYALL)
 					{
 						// found an obstacle
 						clear_xf = fin_xf-dx;