Editing Presenter Materials

Installed archive materials cannot be edited whilst they are in the archives, but you can edit materials in the scene's palette. Edited materials will be saved with the JetStream model in an .nwd or .nwf file, or in an .nwp palette file, or they can be added to your user archive, My Materials

To edit a material, double click on it in the palette, or right click on it and choose Edit... from the context menu. The material editor dialog will appear, which will vary for different types of material. You can't add or remove parameters on a material - merely edit those existing, so it is important to use the right type of material template for the material you want to edit. The dialog for the Breeze block procedural texture is shown below and this will be used as an example of how to edit a material.

Editing the breeze block texture

1. The three buttons at the top determine what sort of material preview you get:

   • Click on the Standard Preview button to get a software generated photorealistic preview of the material on the standard ball against checkered background, which is not interactive but will show how the material will look when rendered photorealistically.

   • Click on the Active Preview button to get an OpenGL interactive preview of the material on the standard ball against checkered background. This is updated interactively while you change the parameters and will resemble the quality of material shown in JetStream Roamer during navigation, but will not be as high a quality as the photorealistic render.

   • Click on the Main Window Preview button to close the preview window in the material editor and instead preview the material on the item in the scene in Roamer's main navigation window. This is updated interactively while you change the parameters and will be exactly the material shown in JetStream Roamer during navigation, but will not be as high a quality as the photorealistic render.

2. For a simple material, there is only a single Material tab on the material editor, whereas for a texture material, whether procedural (generated from an algorithm) or bitmap (generated from an image), there is an extra tab called Texture

   The Material tab contains simple parameters that affect the material's color, scale, shininess and so on. In the case of the breeze block, there are parameters for the overall scale of the material as well as a block's width and height, the blocks' color and mortar color, its roughness and reflectivity. On a bitmap texture, you would also define where the image is that becomes the texture map in the Image File Name text box (see >Creating a texture using your own image). On a glassy material, other factors would affect the transparency and refraction properties of the glass. Some of these factors will not be apparent in the interactive OpenGL window and will have to be rendered with the Render button to be seen.

   The Texture tab contains parameters that specifically affect a texture material's texture mapping properties, such as its rotation, offset (origin) and S- and T- (sometimes called U- and V-) scales. These parameter values are applied in relation to an origin point, (see for more information). There are S- and T- Reflect check boxes, which will show the reflection of the image in either (or both) of these axis. Finally there is an Offset Center check box, that repositions the origin to the center of the image (again, see for more information). When using the Main Window Preview , texture changes can be made instantly allowing interactive positioning of materials on an object.

3. At any time, click on the Apply button to apply the parameter edits to the material in the scene.

4. Click OK to keep the changes made or Cancel to discard any changes made (since the last time you clicked Apply at least).

Creating a texture using your own image

1. From the Templates material archive, double click on the Plain Texture material. This will add the material to the scene's palette and open the Material Editor

   

2. On the Material tab (or Color tab, if in Developer profile) click the Browse (...) button next to the Image File Name text box. The Open Image File dialog is displayed:

   

3. Browse to the location of and select your image file, then click Open

4. You may then need to adjust some of the texture parameters of the new material, for example its scale, rotation, offset or reflection (if it's back to front). These may all be edited in the Texture tab. See for more information on editing materials.