Painting the color maps in Cycles

There are no differences in painting in Blender Internal or in Cycles, because the Paint Tool is exactly the same; the only difference is in the preparation of the materials.

In this recipe, we are not going to repeat the procedure already explained in the previous one; we'll just set up the file for the painting and test whether it's possible to paint in real time on all 5 image textures at the same time, as it is in Blender Internal (spoiler: it is).

Getting ready

Let's start with the Gidiosaurus_painting_BI.blend file; in that file, we already have the UV/Image Editor windows set and the 5 materials assigned to the 5 different UDIM tiles and parts of the mesh.

In case you want to start with a brand new file, here you need to repeat the steps of the Preparing the model to use the UDIM UV tiles recipe in this chapter. Then, continue with the following:

1. Be sure you're in Object Mode.
2. Go to the main top header and click on the Engine to use for rendering button; switch from Blender Render to Cycles Render.
3. Split the 3D view into two horizontal rows and change the top one into a Node Editor window; press the N key to get rid of the Properties sidepanel.
4. In the Material window, select the Material_U0V0 slot; click on the Use Nodes button or select the Use Nodes checkbox in the Node Editor toolbar:
   

   Enabling the nodes for the materials under Cycles

5. Put the mouse pointer inside the Node Editor window and add an Image Texture node (press the Shift + A keys and in the pop-up menu, go to the Texture item to select Image Texture). Connect its Color output to the Color input socket of the Diffuse BSDF node.

   At this point, if we haven't already painted the color textures in Blender Internal, we should load the blank_U0V0.png image in the Image Texture node and then do the same for the other 4 materials.

   Instead, because we already have the color textures, let's load them in the Cycles materials. To see whether everything works as it should, we'll paint on them through the 3D viewport.

6. Click on the double arrows to the side of the Open button in the Image Texture node and select the U0V0_col.png item from the pop-up menu (remember that the 5 color textures are already loaded inside the blend file):
   

   Selecting one of the already loaded images in the Image Texture node for the materials under Cycles

7. Repeat step 4 to step 6 for the other 4 materials.

How to do it…

Now, the steps are really simple:

1. Go to the Brush subpanel and switch the foreground color with the background black color.
2. Trace in the 3D viewport, a continuous stroke enveloping all the Gidiosaurus body parts:
   

   The single stroke test under Cycles

   This is the proof that it works exactly as in Blender Internal.

3. Press Ctrl + Z to undo the stroke and save the file as Gidiosaurus_painting_Cycles.blend.