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Table of Contents

This page provides general guidelines for using multiple V-Ray Decals with V-Ray Displacement.

 

Overview

V-Ray Decal offers you an easy way to project one material on top of another regardless of the target UV set. You can also stack multiple V-Ray Decals that have different materials on top of each other. The projected materials can be masked based on textures.

The Displacement mapping adds more detail on the V-Ray Decal and its geometry without having to model it first.

This tutorial covers the steps for adding several V-Ray Decals that have V-Ray Displacement as well as controlling their order. It also shows complex masking of the projected V-Ray Decals' materials.

The tutorial scene used contains a simple room setting. The V-Ray Decals help to create a procedural wall painting.

The scene objects are taken from the extensive Chaos Cosmos 3D library.

To download the scene files, click the button below.

 

Download Scene Files

 

 

Preparation

Follow the steps of Tutorial Part I to add the VRayDecal and apply materials and displacement to it. You can find it here: How to Apply V-Ray Displacement on V-Ray Decal - Part I


Adding Complex Masks to VRayDecal

Let’s separate the frame and the canvas of the painting by using different materials. For this purpose, use a VRayBlendMtl.

  • Create a VRayBlendMtl and name it Painting_Blend_Mtl.

For the painting frame material:

  • Create a new VRayMtl with a color of your liking. In this case, we use gray with a Value of 50 for the Diffuse color.
  • Set the Value of the Reflection color to 200.
  • Set the Reflection Glossiness to 0.75.
  • Make a copy of the existing Painting_Displacement Gradient Ramp map (see Tutorial Part I) and name it Painting_Base_Displacement. Plug it to the Displace slot of the VRayMtl.
  • Name the new material Painting_Base and then plug it to the Base material slot of the Painting_Blend_Mtl.

For the canvas:

  • Create a new VRayMtl and load a VRayBitmap with the Painting_Coat_Diffuse.jpg file, which is available in the Assets folder (check the downloadable scene files).
  • Set the Value of the Reflection color to 100.
  • Set the Reflection Glossiness to 0.6.
  • Name the material Painting_Coat and then plug it to the Coat 1 slot of the Painting_Blend_Mtl.

 

 

 

Now create a black and white Gradient Ramp mask to separate the two materials. Use the parameters shown in the screenshot for the mask.

Plug the Painting_Blend map to the Blend 1 slot of the Painting_Blend_Mtl.

 

 

 

Render the scene to see the result.

Now, the two elements of the painting have different materials which can be tweaked independently.

 

 

 

In the following example, use the Plain_Natural_Chenille_1474012_28cm #1 material from the Chaos Cosmos library for the canvas.

Plug the material into the Coat 1 slot of the already created VRayBlend material.

Also tweak the Diffuse color of the Painting_Base material to HSV (31, 57, 67) to match the new canvas color better.

 

 

 

Render to see the new version of the Blend material.

 

 

Multiple VRayDecals

You can use multiple V-Ray Decals on top of each other to create complex layered projections. Let’s explore how they work and how to organize them.

  • Select the V-Ray Decal in the viewport and assign to it the existing Painting_Base material which was used as a base for the VRayBlend material.
  • Create a second V-Ray Decal and set its Width to 405, its Length to 92, and its Projection depth to 25.
  • Position the new decal as shown in the screenshot, so that you can use it as a separation of the wall paint in the two parts.

 

 

 

Make sure there is an intersection with the wall.

Use the Exclude button to exclude all the objects in front of the wall.

 

 

 

  • Apply the available Stucco_02 material. It is identical to the Wall Stucco_01 material, except for the diffuse color.
  • Create a mask to break the hard line between the two materials as well as to simulate irregularity from a brush.
  • Create a Gradient Ramp map and set both the Gradient Type and the Interpolation to Linear.
  • Set the Flags and the Noise parameters as shown in the screenshot.
  • Also set the Blur to 0.01 to make the border strip sharper.
  • Rename the map to Stucco_02_Border and plug it to the Mask slot of the second V-Ray Decal.

 

 

 

Let’s see the result.

Everything is arranged as expected. The painting’s decal is in front of the wall’s decal, so both are visible in the render.

If you want the wall’s decal to be on top of the painting, just move it manually or use the Order function of the V-Ray Decal parameters.

 

 

Reorder VRayDecals

Let’s see how to reorder the V-Ray Decals.

  • To move the wall’s decal on top of the painting, select it (i.e. select VRayDecal002) and change its Order to 1 from the parameters.
    Keep in mind that the Order of the painting’s decal is 0 by default.
  • Let’s also create a third decal.
  • Set both its Width and Length to 20. Position the decal in the bottom right corner of the painting.
  • Set the third decal Order to 2, so that it is on top and visible.

 

 

 

  • Create a new material and assign it to the third decal. In the current case, the material is a copy of the Painting_Base material but with a different Diffuse color: HSV (23, 150, 102).
  • To simulate a painting signature, use a texture mask plugged in the Mask slot of the decal. For this particular case, use the Signature_Mask texture, provided in the Assets folder, through a VRayBitmap node.

 

 

 

And here is the result.

Let’s render from a different angle, using the Render_Camera_02, to see the side view of the scene.

 

 

 

Final Result