Paint a head using textures taken from photographs

Tutorial: Using Photoreference

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In this section, we'll show how to paint a head using textures taken from photographs. Some of the steps will be the same as in the previous example, so we'll be referring you back to that at times.

Loading and Capturing Textures

Of course, the first thing to do is to get some textures to use. To do this:
1. Load your photographic reference image using Texture:Import. It'll show up as a thumbnail in the texture palette.
2. Display the image in the canvas by pressing Texture:CropAndFill. This will actually resize the canvas to the size of the image, and then fill the canvas with the image.
3. Change the rendering mode to Render:Flat. This eliminates the shading effects from lighting, and gives you the clearest and brightest view of the reference image.
4. Use the Tool:MRGBZ Grabber tool (this is an icon under the "Current Tool" dropdown menu, not a grey labeled button) to extract specific portions of your photographic textures, as desired. To do this, select the grabber tool, and then Shift-drag out a rectangle on the canvas. The dragged area will be added to the texture palette (at the full resolution of that area--it will not be scaled or cropped).
5. Repeat the above as many times as necessary, to capture all of the textures you want.

In preparation for the next steps:
6. Using Document:New Document, create a new, blank canvas, on which the polypainting will take place.
7. Reset the shading mode to Render:Preview.

Using the Spray Brush for Painting Skin

The Stroke:Spray brush is a great brush for applying copies of a texture over a surface, without the obvious visually repetitive effect that would be seen with other methods, such as texture tiling. Let's start off with painting the model's skin.

1. Follow the steps described in the previous example to set up the head for painting; ensure displacement sculpting is off, set a base color for the skin, etc.

1. To ensure that the textures we are using are not applied to the model as a whole while we are trying to use them, press Tool:Texture:Disable UV.
   Note: Disabling UVs has another major benefit. Without UVs, your model will occupy significantly less memory space. This might provide increased speed, or the ability to perform another level of subdivision, or both.

1. Now choose a texture appropriate to the area of the model you wish to paint. For example, to paint the chin, you might want to choose a texture, taken from the photo reference, that shows unshaven stubble.
2. Choose Stroke:Spray and an appropriate brush size, and paint the skin of the model. As mentioned before, the random nature of this stroke will prevent repetitive texturing. In addition, the smooth falloff provided by the alpha and brush falloff lets the edges of the stroke blend smoothly with whatever other painting exists on the surface of the model.
3. Continue, using different textures, until the base layer of the skin is done.

Of course, this is just an example of how to quickly paint realistic texture over large areas of a model. There are many other ways this could be done, and other techniques would be applicable to painting details.

At any point, you can check to see the effects of the texturing without shading by pressing Render:Flat. This lets you see what the texture colors will be once they are unrolled into the final texture map.

Remember also that you can mask portions of the model's surface to prevent painting over masked areas.

Using the Spray and DragRect Brush for Painting Hair

We can use the Spray brush with hair painting as well, to quickly paint in hair without obvious repetition. However, since we are painting a directionally non-uniform texture (hair has a visual flow), another consideration applies.
When painting with texture, ZBrush maintains a connection between the direction of the brush stroke and the orientation of the texture. To put it another way, the orientation of the texture is not independent of the direction of the brush stroke. If you paint a woodgrain texture using vertical strokes, and then make a horizontal stroke across that painting, the grain in the horizontal stroke will be perpendicular to that from the previous strokes.
In particular, ZBrush orients the texture being painted so that the texture's vertical axis aligns with the direction of the brush stroke. For our hair painting, this means that to obtain the smoothest and clearest hair painting, we should choose a hair texture patch wherein the flow of the hair is close to vertical.
With that bit of explanation out of the way, let's proceed.

1. Choose the Spray stroke, and select as the texture a patch of hair with the hair flow close to the vertical.

# For the smoothest strokes and hair flow, you might also want to activate the Lazy Mouse feature.

1. Now paint in the hair, with your strokes going in the direction of the hair flow. In addition to eliminating tiling effects, the Spray stroke will also introduce some randomization into the orientation of the applied textures, which results in better blending between different strokes.

1. Some of the randomization done by Spray is affected by the orientation of the surface over which it is drawn. If you don't like the effect, just paint over it until you get something you prefer.

And that concludes the use of the Spray stroke to lay down the base of the hair.
Now we'll use the Stroke:DragRect stroke to add highlights to the hair. DragRect is particularly useful when painting (or sculpting) with textures (or alphas), because it allows precise placement, sizing, and orientation of a texture, all with one stroke. In addition, since DragRect does not paint along a path, we aren't constrained in our selection of texture by the direction of hair flow in that texture.

1. Choose a texture to use when highlighting. In our example, we chose one that was brownish, compared to the black of the base hair.

1. Click on a point on the hair where you want the texture to be centered, and then drag out from that point to size the texture, and around that point to rotate the texture. Here is a DragRect stroke applying a selected texture. Notice the rotation. The texture can easily be aligned to match the existing hair flow, or put at an angle to show different patches of hair crossing.