Baseline (Widescreen) Solution & Issues
From the menu the game supports widescreen but it's stretch. You have to change values in the game exe in hex editor to get proper widescreen but the game will be vert-.
The game is also lock to 30 fps.
1.) Open hex editor and and load constantine.exe
2.) Find values AB AA AA 3F (there should be three) and change all values to 39 8E E3 3F for 16:9 and CD CC CC 3F for 16:10
3.) Save it and play the game
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues