A pattern in The Sims 3 has four channels to hold mask information. These are Red, Green, Blue and Alpha (RGBA) where every channel can save a greyscale image. The following tutorial will illustrate the concept of stencil masks (not the making of the pattern itself).

Installing the DDS plug-in

You have to download the Photoshop DDS plug-ins here: http://developer.nvidia.com/object/photoshop_dds_plugins.html

Click on Download Current Version to download the file and then install it.

If your Photoshop is in English the installer might have chosen the right destination in the Photoshop directory for the plug-ins. If it’s not then you have to translate the folders name to know where to move the plug-ins to. The correct folder should be C:\Program Files\Adobe\Adobe Photoshop CSX\plug-ins\file format

Concept

A pattern in The Sims 3 has four channels to hold mask information. These are Red, Green, Blue and Alpha (RGBA) where every channel can save a greyscale image. The following pattern (fig 1) is going to illustrate the concept of stencil masks, not the making of the pattern itself.

    Fig 1

Let’s break up this pattern in its colour layers (fig 2).

    Fig 2

Now we sort these layers in channels and making them greyscale, so they work like alpha masks for the colours. White is fully opaque, black is invisible and greys are transparent (fig 3).

    Fig 3

Create the RGBA Stencil Mask

Open a new 256x256 pixel RGB/8 document (fig 4).

      Fig 4

Change to the Channels tab and add an Alpha (fig 5), since there are four channels in this pattern. You don’t have to add the Alpha channel if you have only 3, 2 or 1 channel used for your pattern. Don’t delete any of the RGB channels. Photoshop won’t like that.

    Fig 5

Copy/paste each of those masks in the correct channel (fig 6).

    Fig 6

With Alpha visible the image will look something like this (fig 7).

     Fig 7

It looks odd but this doesn’t matter as long the masks in channels are correct.

Go to Save as… and choose the D3D/DDS (*.DDS) file format with Alpha channel enabled. Hit Save and the DDS plug-in dialog pops up. Choose the DDS internal format 8.8.8.8 ARGB 32 bpp | unsigned from the drop down list and click Save (fig 8).

    Fig 8

You’re done!

Now move on and import the DDs into the TSR Workshop Pattern Tool!

Note: Almost all kind of meshes in the Sims 3 do have a Stencil Mask. This time they don’t hold colours but are the mask for patterns to compose the final mesh texture.