3D Painting

If all you want to do is apply a solid colour to your 3D object or to certain faces of your 3D object then see the 'materials' page, not this one. If you want to be able to achieve airbrush painting effects then this is the right page for you. There are two ways to airbrush paint your 3D object:

The normal method is to unwrap the surface of the object as if you were removing the peel from an orange. Once the surface has been unwrapped and flattened (just like you a flattened orange peel) it can then be exported into a specialised painting program such as Photoshop or Paint Shop Pro, worked on there and then imported back in again. A problem with this method is that it is necessary to choose the seams carefully where the different parts of the surface will be separated from one another. This method is not explained in this site so if you would like to try this method please check the Blender online manual or one of the many tutorials available on the internet in places like YouTube. A video about unwrapping a human head can be seen HERE and some examples can be seen at the bottom of this page.

Alternatively you can switch to vertex paint mode and paint the 3d object while it is still in 3D. You’ll have to keep rotating it around and some parts might be hard to reach but at least this method is intuitive and there is no problem with seams as in the first method. This is the method explained below.

Vertex Painting

Here’s an exercise you can do to learn about vertex painting.

Note that there seems to be a bug in version 2.5 alpha 2 which interferes with vertex paint if you choose texture paint at any time. DO NOT CHOOSE TEXTURE PAINT and be sure to save your work extra often when working with vertex paint.

Start Blender, delete the default cube and add the monkey mesh. The monkey mesh will be facing the sky but you can make her face forwards (her name is Suzanne, by the way) by doing R, X, 90, Enter on the keyboard (i.e. rotate 90° about the X axis). Suzanne probably has a rough shape made of obvious flat faces – you make her look smoother by turning on the Smooth option in the toolbox at the left of the 3D window (if you can’t see the toolbox press T). But if you look closely (and maybe zoom in) you will notice that the edges of Suzanne’s head are just as rough as they were before, so Smooth does not actually smooth the shape, it simply smoothes the colours within each face so that the edges between the faces are less obvious. You can convince yourself of this by going into wireframe mode (press Z) and you will see that that the original crude set of edges has not changed. Press Z again to exit wireframe mode.

Vertex Paint mode actually works better on a shape that is truly smoother (i.e. more faces, not just recoloured faces). To increase the number of faces and get a smoother shape we will use the subdivision surface modifier (also called subsurf). See the Modifiers page for more information about the subsurf modifier. With Suzanne still selected in object mode, click the Modifiers icon and add a Subdivision Surface modifier. Set the subdivision levels to 2 for viewing and 3 for rendering.

Explanation to finish.....

UV Unwrap

As previously stated, this method is not explained on this site, but I thought you might like to see a couple of images showing the Suzanne monkey head being unwrapped, painted and then rendered:

Here is the flat UV image. The two circles at the bottom are the eyes:

The UV unwrap being painted:

The finished result, with the UV surface applied to Suzanne's head and then rendered:

These images are from HERE.