Sorry. Stylized paintings are not reflective of the reality. For one thing, most colonists did not have such uniforms. Many were lucky to have adequate shoes or a winter coat. The reality was not glorious, it was brutal, grim, cold, and hungry; with the ever present threat of sickness due to contaminated water.
Such scenes as that painting are a fantasy of the conditions the troops faced.
Hate to break it to you, Comrade, but that is an official U.S. Defense Department painting depicting the Battle of Guilford Court House, based on eyewitness accounts of the battle, which absolutely was fought between two lines of Continentals and British Regulars.
And YES, by March 1781, Continental troops were well-uniformed and equipped by the French, with the so-called "lottery uniforms," contract hats with cockades, and Charleville Muskets with bayonets.