Materials Tab

Materials Tab

Like the LightsEffects and Rendering tabs, the materials tab is divided into two panes. The left-hand pane describes the pre-defined archives of materials that are installed and the right-hand pane shows the current palette of materials that have been defined and are being used in the scene. The palette also shows a small thumbnail of the material as it will appear when rendered.

The following sections will describe how to manage and edit materials for application onto items in the scene.

Applying Presenter Materials

Applying Presenter Materials

Materials can be applied to items in the scene by dragging-and-dropping the material onto:

• an item in the scene;

• an item in the selection tree;

• a selection set.

If you drag the material from an archive then it will appear in the palette where it can be edited and saved with the scene if necessary.

Presenter uses Roamer's selection resolution to decide which items to apply the material to when dragging from an archive or palette onto the main view. When hovering over any item in the main view, the proposed selection will turn the selection color (blue by default). When you drop the material onto the current selection, it will be applied to all the items selected. If you drop the material onto an item that is not currently selected, it will be applied to just that item.

You can also apply materials to items by selecting the items in the JetStream selection tree or scene and then right-clicking on the material in the palette and selecting Apply to selected items from the context menu.

Rules can also be used to apply materials to items based on their layer or color or selection set names, for example. See for more information on this.

Applying a material to items

1. Select the items in the main navigation window, or by using the selection tree.

2. Choose your material from an archive or palette, right click on this material and choose Apply to selected items from the context menu to assign the material to those items selected. Note that the material will only be applied to those items and not to every instance of the item, if it is a multiply instanced block or cell. To assign the material to all instances of a multiply instanced block or cell in the scene, instead choose Apply to all instances of selection from the context menu.

3. Alternatively, you can simply drag-and-drop a material from an archive or palette onto items in the selection tree or main navigation window to assign those materials to the items. Note that the selection resolution determines which items will receive the materials. See the section called "Selection Resolution" in the chapter called "Selecting" in the Roamer book for more information on selection resolution.

Removing Presenter Materials

Removing Presenter Materials

You can remove materials assigned to items either from the material or from the item:

Removing a material from items

1. Right click on the item in the main navigation window, or the selection tree and choose Presenter, Remove Material from the context menu. This item on the menu will only be available if the item right clicked on has a material assigned to it at that selection resolution in the tree - see the section on >Inheritance below.

2. Alternatively, right click on the material in the palette that you want to remove from items in the scene.

3. From the context menu, choose Remove from all items to remove all assignments of the material from all items in the scene.

4. If you have items selected in the main navigation window or selection tree, then you can choose choose Remove from selected items from the context menu to remove that material from only those items you have selected in the scene.

   Note

   Deleting the material from the palette will automatically remove that material from any items in the scene which it was applied to.

Inheritance

Layers can have colors, just as geometry can. If a layer has a material, all its children in the selection tree inherit this material, until one of the children is assigned its own material, at which point, all its children in the selection tree inherit this material, and so on.

If you drag-and-drop materials onto layers, this works fine because only the layer picks up the material and although its children inherit the material, they do not have it explicitly assigned to them.

Therefore right clicking on such a child will not allow you to remove the material because one was not explicitly assigned in the first place.

However if you use a rule to assign a material to a certain color, then all objects in the scene will get this material explicitly assigned to them, including parent layers and child objects. If, with a selection resolution of something like Geometry (which is more specific than a resolution of Layer ), you right-click on a child object and choose Remove Materials from the context menu, then the material will be removed from the child object, but not from the parent layer and there won't be any apparent difference.

To remove the material, you will therefore have to remove it from the parent object, in the above situation this would be the layer.

Managing Materials

Managing Materials

The palette is where you edit and manage your materials for your scene. Materials are taken from the archives into the palette where they are edited. You can then save the palette into a JetStream Palette file (.nwp) for use in other scenes too.

Managing Palette Materials

1. Right click on a material in the right hand pane of the Materials tab (the palette).

2. Click Delete to delete the material from the palette. This will also remove the material from all items in the scene.

3. Click Copy to copy the material to the clipboard. Right click on an empty space in the palette and choose Paste to paste a copy of the material with a the same name suffixed with the next number in the list. This process is useful if you want to test small tweaks to a material.

4. Click Rename to rename the material. You can also select the material and press F2 to rename it.

5. Click Regenerate Image to regenerate the thumbnail of the material in the palette with the current attributes.

6. Click Select all instances to select the items in the scene which have this particular material assigned to them.

7. Depending on whether items are selected in the scene and whether the material has been assigned to any items, there will also be a couple of Apply and Remove items on the context menu. See and for more details on these.

8. Click Clear Palette to delete all the materials from the palette and also from all items in the scene.

9. Click Load Palette... to load a previously saved palette of materials into the current scene. This will delete any materials currently in the palette. The standard File Open dialog will appear, allowing you to browse to an .nwp file.

10. Click Append Palette... to load a palette from an .nwp file, while keeping all the existing materials in the current palette. Any materials that are duplicated will be renamed with the .nwp file as an extension.

11. Click Merge Palette... to merge a palette from an .nwp file into the current scene. This is like appending, but instead of adding and renaming any duplicate materials, merging will overwrite existing materials of the same name.

12. Click Save Palette As... to save your current palette of materials into a NavisWorks Palette (.nwp) file. If you save the current scene using the usual File, Save method into an .nwf or .nwd file, the palette will be saved too, but the independent .nwp file is useful if you want to transfer materials you've made in one scene into other scenes.

    Note

    If you publish an .nwd file, using the File, Publish command (only available if you have a valid JetStream Publisher license) a _Presenter_Maps folder will be created along with the .nwd file. This folder will contain any materials that are not contained in Presenter runtime , which is used by both JetStream Roamer and NavisWorks Freedom, to view materials.

13. Click Edit... or simply double click on a material to open the material editor dialog, allowing you to edit its parameters. See for more information on this.

Editing Presenter Materials

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.

Advanced Materials

Advanced Materials

Internally a material is defined by four shaders from different classes - Color, Transparency, Reflectance and Displacement. Each class of shader controls a different aspect of a material's behavior. There are many types of shader in each class, each type being defined by its own set of parameters.

• A color shader is used to define the color of a surface at any point in space. It may be as simple as a plain color which specifies all parts of the surface to have a uniform color, or it may define complex surface patterns such as marble or wood. Every material must have a color shader.

• A transparency shader is used to define how transparent or opaque a surface is, and thus how much light is able to pass through it. Transparency shaders range from a simple uniform transparency to more complex regular or irregular eroded patterns that would be more difficult to represent using modelling techniques. A material without a transparency shader is completely opaque.

• The behavior of a surface in the presence light is represented by a reflectance shader which defines how much light is reflected by the surface towards the viewer. Shaders of this class may be thought of as defining a surface's "finish", and are used to model properties such as matte, metal and plastic.

• Small surface perturbations can be supported by means of displacement shaders. Typically, a displacement shader will give an otherwise smooth surface an irregular or indented appearance. Displacement shaders are used to represent features that would be difficult, impossible, or inefficient if conventional modelling techniques were used. For example, rough metal castings and the regular indentations produced by pressed sheet metal can be simulated.

Normally the material editor displays a selection of the most important parameters from all shaders within the material tab. If the user profile (see the section called "Profiles" in the chapter called "Interface" in the Roamer book for more information on this) is set to Developer , then all four shaders can be edited and changed individually.

Some shaders are described as "wrapped". These define a flat, two dimensional material, like wall paper. Wrapped materials need a texture space shader to define how they should be applied to (wrapped around) a three dimensional object. Materials that include a wrapped shader can also include a texture space shader. A special type of texture space shader, called a layout shader, can be used to transform (rotate, stretch, offset) the two dimensional material before it is applied to the three dimensional object. Transforms are based around an origin point, which by default, is the top left hand corner of the image (refer to the diagram below, where the image is enscribed in the red square, which is then repeated. The default origin is Point 1 ). Checking the Offset Center check box will reposition the origin to the center of the image (Point 2 ). Finally, in Developer profile, you can edit the Decal Mode , choosing from either Default or Normalized . Selecting Normalized will move the origin to the lower left corner of the image (Point 3 , with the Offset Center option un-checked). With both Normalized and Offset Center selected, the origin will be repositioned in the center of the repeated image, directly below (Point 4

In Presenter, materials that include a wrapped shader also have a layout texture space shader associated with them. Normal texture space shaders are associated with objects.