What are image maps?

An image map (sometimes called texture map) is a regular picture file in an image format such as jpeg, bmp, tiff, or png. Image maps are used in materials to create specific effects or patterns.

They are known by various names depending on the parameters they are used for:

• Color maps replace a solid color with an image that repeats across a surface. For example, cloth or wood patterns.
• Highlight maps (or specular maps) create the appearance of relief. Specular maps work best to create visible noise that in the real world if touched would feel smooth. For example, metallic paint.
• Reflection maps provide an image that is reflected off shiny objects. The default in Hardware rendering is to use the environment’s reflection map, so that the object reflects the environment.
  NoteReflection maps have no effect in Ray Tracing. The reflections in Ray Tracing will accurately reflect the environment and other objects in the scene. A large visual difference will be seen between Hardware rendering and Ray Tracing if a reflection map is used.
• Transparency maps determine which parts of an object are opaque and which parts are transparent. They can be used for materials with holes punched out such as a metal grill or perforated rubber. Darker areas of the transparency map produce an opaque material, while brighter areas create a more transparent appearance.

  Often a transparency map is the inverse of a color map. If the color map image format has an alpha channel, you can use that alpha as the transparency map.

• Bump maps break up the relief of a surface. In the real world, if the surface were touched it would feel bumpy. For example, tire treads or rough plastic.

  Bump textures must be normal maps (that is, they must contain elevation as well as vector information).

• Decal maps define the shape and transparency of a decal material. This is similar to a transparency map, except that decals can be layered on top of other materials. For example, the numbers on a keypad or a painted logo.

Apply image maps

1. Select the surfaces you want to work with.

   (The texture is applied over all of the surfaces you select.)

2. Click the Use image file radio button. (Decals require the use of an image file.)

   

3. Click the folder icon to browse to and select a texture map file.
   NoteFile names should not contain special characters.

   (After importing the file, the date the file was imported appears beneath the browse field for your reference.)

4. To align the texture map to the surface, use the appropriate Mapping type option:

   Parametric (UV)

   No projection is used. Instead, the image is mapped to the UV coordinates of the surface. Each surface is mapped separately, so adjoining surfaces may show seams.

   Planar

   The projection of a texture or image as if the image were placed on a level surface and projected onto the object. Use this option to apply a texture to one or more surfaces that are relatively flat, such as wood paneling.

   Triplanar

   The projection of a texture from three perpendicular planes. Use this option for complex surfaces where the texture needs to be applied from multiple angles to follow the contours of an object.

   Cylindrical

   The projection of an image onto an object, as if the image were rolled into a tube and projected inwards towards the object. Use this option to apply a texture to the edge of a circular surface, such as a car tire tread.

5. Move the image map to best fit the surface. (See the next topics.)
6. To reload an image file after you have made changes to it, click the Reload button.

Link texture settings for image maps

To keep multiple image maps (Color, Highlight, Bump, etc.) aligned during the process of mapping and moving them, check Use settings for all textures above the mapping controls.

Once this option is checked for a single image map, all other image maps in the material inherit the same mapping type, tiling, repeats, and transforms.

When this option is checked, the checkbox for all image maps will read Texture settings linked. Once this is active, changing the options for any image map in the material will change them all.

Repeat textures for cylindrical mapping

For cylindrical mapping, use the Radial repeat value to repeat the texture several times around the surface. For the textures to repeat uniformly, it is recommended that you type an integer value (1, 2, 3, 4, and so on).

Or, use the manipulator to drag the texture interactively:

Turn off texture tiling

To apply marks, blemishes, decals or labels to one area on a surface, you can turn off texture tiling in both of the U and V directions. Or, turn it off in one direction so the texture pattern repeats horizontally or vertically (like wallpaper).

To turn off texture tiling:

1. In Tile texture in, click off either (or both) U direction or V direction.
   • If you turn texture tiling on for both U and V, the texture is repeated horizontally and vertically across the entire surface.

     

     (This is the default setting for most materials.)

   • If you turn texture tiling on in one direction, it is repeated only in that direction from edge to edge over the surface.

     

     (The background is determined by the Color setting.)

   • If you turn texture tiling off in both directions, you can apply marks, blemishes, decals or labels to one part of a surface.

     

     (The background is determined by the Color setting.)