Smoke

Smoke

Smoke reduces accuracy of many weapons, most of them projectiles, weapons such as the grenade, artillery or flamethrowers are not affected by smoke.
For a complete list of which weapons are affected, check out the Weapons vs Targets Tables.

The size of a smoke cloude is 8x8x8, most likely a cube instead of a sphere

All projectiles that needs to go through a smoke cloud is affected, units does not have to be inside the smoke to receive cover bonuses, and launching smoke on enemy weapons works just as well.

Smoke Launchers

Weapon	Smoke Cloud Count	Animation Duration	Effect Duration	Range
American Mortar Smoke	6	30	30	75
Sherman Smoke Launcher	1	28	28	0
Wehrmacht Mortar Smoke	5	30	30	85
Rifle Grenade Smoke	2	30	30	35
Tetrarch Smoke Launcher	2	30	30	30
Tetrarch Smoke Barrage	10	30	30	45
Command Tank Smoke Barrage	10	30	30	45
Animation duration appears to be about 30s for all smoke clouds except Sherman (It is cut short).
Tetrarch and Command Tank smoke are dropped like creeping barrage, selection area is 50x6.

Commando Smoke

Commando Smoke is unique, it only affects things inside of the smoke, make one step outside and your bonus is gone.

Commando Smoke lasts 14 seconds.

Other Smoke

Red Smoke: Artillery warning. Get out of the way.
Green Smoke: Paradrop signal, and Victor Target. Heads up.