Using ZBrush BPR and NPR filters to render your models with an ‘illustration mood’
Once you have downloaded the ZBrush render presets for illustration, setting up the document is really simple. If all you have is a 3D mesh with a grey MatCap, the filters from the preset probably won’t give you the results you are expecting. For best results, you should have some polypaint on your mesh or at least a MatCap with some color in it.
First, go ahead and load the preset by clicking on the ‘Load’ button from the Render palette and selecting the ZBGs_Simple_Illustration.ZRP file. To check that the preset was loaded, you can open up the ‘BPR Filters’ subpalette and you should see that the 12 filters are enabled (F1, F2, etc).
If you do a quick BPR render (Shift + R) with a mesh that has no polypaint and the MatCap grey, you should get something like the image below:
The next step in setting up your ZBrush document is to change the background color to something lighter than the default grey and with a bit of color (the hue is totally up to you). The reason is important to change the background color for this render preset to work, is that there are a couple of filters that are working with ‘Overlay’ as a blending mode. If you have a background color that is too dark, the overlay effect won’t be very evident.
With the updated, lighter background color, you should now be able to see the ‘paper texture’ from one of the filters that is using the ‘overlay’ blending mode. This should already give you a nice looking render even without polypaint on your mesh.
Now that the preset is loaded and we have nice background color, you can enable or add some poly paint on your mesh. For this quick guide, I’ve been using my Cassowary model which has some interesting set of details as well as a good range of colors in polypaint:
This is the effect of the Render preset with the colored background and polypaint enabled:
Editing the look and feel of the illustration render is really simple. You can go over each filter from the BPR filter subpalette and turn them On and OFF so you can see what they do (you don’t have to re-render to see the effect).
The main filter that will have a greater impact on your render is probably the F8 which is the filter with the paper textures. So, you can load your own paper texture or any type of texture in ZBrush and select it from the texture thumbnail within this filter.
The best textures for this illustration style are the ones that have subtle changes in hue and are, for the most part, very bright. Remember that his texture is set to overlay, so the color of your background will also change the contrast and hue of the render.
Here is an example of the same render preset but just changing the ‘paper texture’ that is used as an overlay. The color changes slightly and some of the ‘dirt’ areas are stronger.
Depending on the resolution of the texture you load, you might see it being repeated a few times or ‘cropped’. You can adjust the size of the texture from the ‘Texture Overlay’ slider (the one right below the blending mode button).
Besides the type of texture you choose to overlay and the background color you choose, you can also tweak the hue and saturation by changing the ‘front’ color of this overlay filter (F8). This front color works better if is a lighter color and roughly the same hue as the background, but you can experiment with it to see how it changes the effect.
Finally, you can also toggle OFF the last filter (F12) which is an ‘Outline Cavity’ filter. The idea of this filter is to sharpen and re-define some of the edges and lines on your mesh but depending on the type of model you have you might want to turn this one off.