This utility is a helper function to convert your Specular Level bitmap into the Alpha channel of another bitmap.
NOTE: For accurate results, update WW to 4.0.20+.
In Source materials, you cannot simultaneously use $envmapmask (Specular Level) and $bumpmap (Bump). But you can use a Specular Level if you store the Specular Level in the Alpha channel of one of the following maps: Bump, Self-Illumination or Diffuse.
The purpose of this tool is an attempt to let you do that inside 3ds Max instead of having to composite the Specular Level into the Alpha of these in another application (like Photoshop, PHOTO-PAINT or Gimp).
- Open Alpha Spec.
- Select items in the scene that have materials.
- Press the Update Material List button. Any materials that have both Specular Level and Bump/Displacement will be listed.
- From that list, select the material you want to convert.
- Choose the target map to send the specular to as an Alpha. Note the tool lists all of these regardless of whether the material has these.
- When sure, click the Do It button.
- A dialog to save the new bitmap appears. Save the new image as a TGA. Important: make this a 32bit image with pre-multiplied alpha (and likely the gamma override of 1.0 especially if making a normal map).
- The new image is assigned to Specular Level and the target slot.
When you click the Do It button, the tool will:
- Paste the Specular Level into the alpha channel of the target bitmap.
- Save the target bitmap with this new alpha channel as a new image.
- Unlink the current Specular Level map and Target map from the material.
- Assign the New bitmap to the Specular Level and Target slot.
- Display the resulting bitmap.
Considerations and Notes
Getting the Alpha
When you save the new TGA, make sure to choose 32bit with pre-multiplied alpha (and for normal maps always use a gamma override of 1.0). If you do not do this, you may not find accurate results.
Inverting the Alpha
There is a button in the UI to Invert the Alpha. This is useful when putting the alpha into the diffuse map and using the textures for glass (or similar materials).