Part 4: Creating a 2D bump texture
 
 
 

In this section, you will create a shader for the Grip surface by duplicating an existing shader. Then, you will apply a bump map to the new shader to create the effect of a bumpy surface.

Watch Part 4 of the tutorial.

Creating a shader for the Grip surface

  1. Open the Multi-lister.
  2. Click the Plastic shader to make it active.

  3. In the Multi-lister, select the Copy command (Edit > Copy).

    A new shader is created called Plastic#2. We are creating a shader instead of modifying the original plastic shader, because the original shader was also shared by the Decorations layer. We don’t want to change the shader on the decorations, just on the grip.

  4. In the layer bar of the modeling window, click the Grip layer button, and select the Pick Objects option.

    The grip becomes active.

  5. Assign the new Plastic#2 shader to the grip.

  6. Choose Pick > Nothing to deselect all objects.
  7. Double-click the Plastic#2 shader to open the shader's control window.

    You will change the characteristics of the material to be more like a hard sponge. The surface will still be somewhat shiny, but will not be very reflective.

  8. Set the Diffuse parameter to 0.2.

  9. Set the Shinyness value to 2.

  10. Click the color swatch to open the Color Editor.

  11. In the Color Editor, click to open the Swatches section, click a red swatch, then close the Color Editor.

    At the Shader Name cell, change the shader name to Grip.

Creating a bump map for the Grip shader

To create an effect of a bump on a surface, you use a technique called bump mapping. Any image can be used as a source for creating a bump on a surface. Typically, the image used in a bump map is gray scale. For example, to create a golf ball, you would use an image that was all white with gray circles darkening to black at their centers on it. The computer would push the surface inwards everywhere there was a dark circle on the image. The darker the color, the farther it gets pushed from the surface.

It is important to note that bump maps create the appearance of a bump on a surface, but do not affect the surface. The edge of a bumped object will retain its original smoothness. If you need to the edge or profile of an object to be bumpy as well, consider using a displacement map, which alters the surface when the image is rendered.

Now, you will create a bump map on the grip shader using a texture from within Alias.

  1. In the Grip control window, click the Special Effects tab.

  2. Click the Map button next to the Bump parameter.

    The Texture Procedures window is opened.

  3. In the Surface section, click the Bulge texture. You will use this texture as the image in the bump mapping procedure.

    The Bulge control window is opened.

  4. Click the Surface Placement tab to open it.

    The Surface Placement parameters control the number of times the image is repeated across the surface.

  5. Click the Urepeat field and type 20, then press (Windows) or (Mac). Click the Vrepeat field and type 20, then press (Windows) or (Mac).

  6. Look at the Grip swatch in the Multi-lister. The bulge texture is apparent.

  7. Close the control window and the Multi-lister.

Rendering the scene

Now, you will render the scene to see the bumpy grip texture.

  1. Select the Render command (Render > Render).

    The File Browser opens to the pix directory of the Lessons project.

  2. Type render5 in the Object name field (Windows) or Save As field (Mac), then click the Save button.

    The File Browser closes and the render begins.

  3. Select the Show button on the Render Monitor to view the rendered image.

    The grip now has a bumpy surface.

  4. Close the rendered image and Render Monitor.

Save your work

  1. Choose File > Save As to open the File Browser.
  2. Save your work in the wire file of the Lessons directory.
  3. Name your file myadv_rend4.wire.