#Knicks’ RJ Barrett has become force from 3-point land

If this continues, RJ Barrett will be in the 3-point shooting contest next All-Star Weekend — if not in the main event.

Barrett’s stark rise from beyond the 3-point stripe hit its climax in Boston, where he drilled all six of his 3 pointers, finishing with 29 points despite a 101-99 Knicks loss to the Celtics on Wednesday night at TD Garden.

Barrett finished with 29 points, shooting 10-for-14 overall. In his last 40 games, after a slow start, Barrett is shooting 45.9 percent from 3-point range (61-for-133). In the past five games, he shot 16-for-22.

While Barrett did commit a costly turnover down the stretch, leading to a Jaylen Brown fast-break layup, he bounced back to hit a game-tying 3-pointer soon after.

“I don’t know if I’m surprised because I see the time he’s put into it,’’ coach Tom Thibodeau said. “And when we’ve been home, he usually comes in every night to shoot and get extra shooting in. He’s really worked hard improving the shot and I think he’s gotten real comfortable behind the line. And I also think his teammates are also doing a good job looking for him. We’ve had good rim reads and a lot of spray-outs, so they’re good-rhythm 3s.”

During an up-and-down first season, when he was left off the two All-Rookie teams, Barrett shot just 31 percent from 3-point range. He’s now up to nearly 37 percent.

“I just work at it,’’ Barrett said. “Going to the gym at night, the more you put into the game, the more you get out.”