PBR texturing in 3D coat, Jaakko Saari 2016 (3D Coat ver. 4.7.06 Windows 64bit) Please see my 3D-Coat 4.7 2016 review here.
Introduction to PBR texturing in 3D Coat
3D Coat has always shined when it comes to per-pixel painting. This feature has been very useful and even better than zBrush polypainting as the resolution of the texture doesn’t depend on the polygon density of the object. New PBR texturing in 3D coat is very attractive to many 3D modelers and texture artists. I’d like to take a look what we can come up just by using and modifying the ready made Smart Materials and stencils.
3D Coat can export both metal-rough and spec-gloss PBR textures. You can choose one in Export Options.
Painting UV Mapped Mesh in 3D Coat
First, let’s select Paint UV Mapped Mesh (Per-pixel) from the start up menu. Alternatively you can go to File, Import and select Model for Per Pixel Painting.
The Paint UV Mapped Mesh menu will appear. You can select one of the pre-made 3d models or import your own. I’m going to click the folder button and import our object to the scene.
Import Object for Per Pixel Painting dialog box informs you kindly that this works with intersecting or mirrored UVs.
There are couple of settings to mind of. If you have baked custom normal maps in software such as xNormal and want to preserve your mesh normals, do click Lock Normals. You can also select Normal Map Software Preset. Obviously it’s good to select the one that corresponds the tool you used. You may also triangulate if needed.
If your model already have UVs in them , you can keep the default “Keep UV”. Since we have already done UV unwrapping for our object, I’m going to select it. You can also name your UV Set Name here and select texture resolution. I’m going to keep the default at 1024×1024 but it’s good to increase it for further detail.
We have now loaded the object into the Paint room and we are ready to start to do PBR texturing in 3D Coat. Notice that we have three panels on the right side of the window. You can customise those but these are the defaults. The most important panel is the lowest one where we can see Layers.
These layers work similarly as in Photoshop. You can choose blending modes, and each layer have several channels such as Metal, Roughness, Depth and Color Opacity (which is oddly named just Opacity), and you can tweak the opacity of each channel independently by percentage. What comes to blending modes there’s plenty to choose from, and they work similarly as in Photoshop.
Now, let’s go to the Smart Materials panel and click one of the metals. 3D Coat will ask you “The Smart Material requires ambient occlusion layer. Do you want to calculate it right now?”. Yes, right now please. We will choose OK. We can keep default settings for the Occlusion Parameters and hit OK.
We have very handy Smart Material Preview window which is resizable. So if we are using old computer or have a very complex model, choosing a small area to preview can greatly improve the performance. You can browse different metals smart materials to find the one that pleases you.
Now, you should see a floating “Preview options” panel above. You can select several options here, mainly the method of applying the texture. But you can also do From Camera, Cylindrical, Spherical or UV-Mapping. I like Cube Mapping because it’s completely seamless. What’s really nice about this panel is the magnifying glass. What this does is that it allows scaling of the texture of the smart material. If some details look too large or small in your model, you can easily resize them. You can also move and rotate and non uniformly scale the texture.
Make sure that the Opacity, Roughness and Metalness percentages on top of the window are all at 100%.
We can now right click Layer 1 and choose option “Fill whole layer”. Then, let’s double click this layer and rename it to BaseMetal. We can preview and check our object in full PBR glory. Congratulations. You have just PBR textured a metal asset. The result should look like this.
But let’s add further detail.
Let’s Add a new layer by clicking the button of the lower right of Layers panel. Let’s name this layer PaintLayer. We can go to paints in Smart Materials tab and pick the one we like. I’m going to choose this beige one which I created myself. You can experiment with any. Again, use Smart Material Preview to get an idea how it will look like.
Now, we can again use magnifying glass button in Preview options to get a nice scale of the effect. Now, I’d like to edit the curvature effect more. This effect is based on the Curvature Map that is automatically generated for you. So I will right click the smart material I chose, and select Smart Material Editor.
We have plenty of options here, but I’d like to focus in Overall Cavity Modulator. This will allow to change strength of the Curvature Map, which means that you can choose how strongly you want the worn-edges effect to appear. I like extreme effect so I am going to choose something around 5 or 6. I’m going to give this Smart Material a new name, and hit Save as New. And again I will right click our PaintLayer and select Fill Whole Model.
Now we can further tweak the paint layer. I like to chip some parts of the paint so that it looks less uniform and more organic. I’m going to select Eraser Tool. I will select hard looking alpha from the Alphas panel, and start to chip away the paint. It’s nicer to use those without much falloff to this task since we want the transition between painted area and bare metal to be sharp. You can scroll with the mouse wheel to change size of the brush. It’s nice to accentuate some of the worn edge effects, and also I like to use square alpha for this, changing the brush size constantly.
Let’s use a stencil for cracked paint effect. In the middle panel, clicl Stencils and select OT_random6. We can then scale this by using the magnifying glass in the preview options. We can also use rust. And now when we erase the stencil is applied and we only erase certain areas.
When we are happy with the result, we can move on and add some dirt to this. Again I’m going to add new layer and name it Dirt1. Before we continue, please click “Close” in Stencils window, otherwise the stencil will be applied to next smart material. I’m going to navigate to Dirt and click on the paint brush icon in the left toolbar to get our smart materials preview. You can browse between different kinds of dirts. I like dirt_2.
Notice how the dirt seems to accumulate in occluded areas. This is based on the AmbientOcclusion map the 3D coat rendered for us earlier. I’m again going to scale this using the magnifying glass and click Fill Whole Layer.
I would however like to add additional hand painted dirt. I’m going to create new layer Dirt2. Let’s do this. This time I will choose dust_1. Now, let’s not fill whole layer but instead paint the effect in using the brush. So we can move Smart Material Preview out of the way and paint. Remember that you can adjust the scale of the texture while painting. You can add hand painted details anytime during the workflow. This is definitely one of the benefits of doing PBR texturing in 3D Coat.
If you want to add further layers, go ahead.
Let’s preview the textures we have created. I’m going grab the Texture editor panel and resize it to be larger. Please note, that you can paint on this editor just the same way as you can on surface of the model. This is the same thing, just in 2D plane
Here we see our Color map or Albedo as it’s called in PBR texturing. This is what it should be, color data only, no fake highlights or ambient occlusion in it. We can preview Normals, Roughness and Metalness as well. The way how Metal-Roughness PBR workflow works is that basically what is considered as metal is white, and black values are non-metal, in our case paint. The roughness is a definition of micro surface detail, such as dust and dirt. What is more rough appears less glossy. We can paint on any of these maps to further define them. It’s nice that we can also toggle wireframe on this window.
Finally, to export our textures, we can go to File and select Export Objects & Textures. I will Export geometry, select Output mesh. In Texture Export/Import Workflow I choose Roughness/Metalness. If you are exporting your textures to Unreal Engine 4 for example choose this. The Spec-Gloss workflow is also supported.
We can choose several presets to export to, for example Unreal 4. This will export a lot of maps, including Displacement and Ambient Occlusion. I will just keep it as default and click checkboxes to export Color, Roughness, Normal, Metalness and AO. Now the textures are ready to go.
I hope you enjoyed this tutorial on PBR texturing in 3D Coat. Here is the video tutorial.
I don’t see any ambient occlusion in the shots before you added dirt.
i have the same problem, 3d-coat (after 4.5) doesn’t calculate occlusion anymore, just a white sheet.