How is this person sampling normals whilst painting in viewport?

[bluberry (T)]

3d paintings in blender! My two cents on hand-painting normal maps.

I am watching a video tutorial about custom painting normals of a character to give it a handpainted effect.

From 3:35 in this video, the artist somehow paints the normals whilst still in viewport mode. He samples color from the character directly, but somehow Blender makes it so that he is sampling the NORMALS colors and not the base color of the character.

It’s not really explained how he exactly does this.

How is he doing this? I tried to follow the tutorial but I can only sample the BASE COLOR of my model instead of the normals of my character.

[Okidoki]

I do not know what you mean by “Viewport” mode.
Anyway:
At the mentioned 3:35 he (simply) switches to texture paint mode and (what he didn’t showed) properly uses the texture image also as base color to “see” it.

You may also have a closer look at other sources for this like here on BA:

Painting brushes and creating a painterly effect with Geometry Nodes

Hello everyone! For the past few weeks, I’ve been trying to make a painterly effect that fits my workflow and my desired look. After a lot of trials, I decided to do it using Geometry Nodes. I mainly follow @Alan_Wyatt 's live paint filter video as a primary guide alongside a bunch of other videos on similar topics and Geometry Nodes. I finally came up with this attempt, but after several tests later, I found too many unworkable limitations and drawbacks and was about to drop the whole thing…

Or look also for/at any other paintly look tutorial (maybe adding also normal as keyword ) like for example this:

Making 3D animation look painterly (it's easier than you think)