Modifying material previews

Garry Curtis & Robert den Broeder, June 20th 2005. A tutorial for Realsoft3D V5+

Beginner/intermediate level.


Realsoft3D's user interface is extremely configurable. One of the options you have, is to change the size and shape of your material previews. This small tutorial shows you how to create a new type of preview and how to change the size of both the preview window and the materials tab of the Select window.

From list to preview

When you click the material tab in the Select Window, using the default program settings, Realsoft3D shows you all available materials alphabetically ordered and shows a small icon beside each material name.

Materials listed in default program settings

This list can easily be changed to present the available materials in a more intuitive and interactive way to the user: the material preview. Try this: make sure you are at the Materials tab, then click with the right mouse button anywhere in the Select Window and select 'Show Previews' from the pop-up menu. You will find this option almost at the bottom of the pop-up. Note, that the next time you open the pop-up menu, you see a small check-sign at the Show Previews entry. Selecting this option again, changes the display back to the list of icons with text labels.

Before Show Previews....                                      and after Show Previews...

As you can see, the previews are all spheres. Some spheres, like the one used with the Fog and with the Marble1 materials, are displayed more close up, thus filling up most part of the small preview window. Let's investigate some more about the configurability of these material previews.

The material property window

If you wish to change one or more properties of any material, you need to open the material property window. This is done, as you probably know, by double clicking on a material preview icon, or by selecting 'Properties' from the pop-up menu. The material property window opens and by default shows a basic interface that allows you to change almost any property of the selected material. But that is not what we're after this time. This time we will have a look at the material preview window.

The small sphere shaped material preview we have seen in the Materials tab of the Select Window is also available in the material property window, but this is not switched on by default. Click the 'Preview' checkbox at the top of the material property window, to see the default sphere shaped material preview.

Preview option checked

Changing the preview type

There are several different material previews available for the user to select. These are hidden in a
pop-up menu in the material property window. Let's have a look at these. Open for instance the material property window for the 'brushsteel'  material and check the Preview checkbox. Now click the right mouse button, when you hover your mouse pointer over the preview image. A small pop-up menu shows:

Pop-up menu in the material property window          Post particles preview selected

Try some of these settings and see what happens to the preview image. If you wish to go back to the default material display, select 'material preview'  from the pop-up menu.

By the way, Realsoft3D offers another way to select a different preview type. In the Material Property window, there is a small button with three dots in it that allows you to directly access the previews directory. This button is only there if the Preview checkbox is ticked. Click the small button and a requester opens, allowing you to select and load any of the available preview types. The small rendered preview in the Material Property window will be updated immediately. The default project can be restored here also by clearing the 'File' name string.

Click the small dotted button to directly access the Previews directory

Please note that the Ctrl key and Shift key  modifiers also work on the material preview window. So, click right mouse button with Shift key pressed and held: zoom preview in and out and click right mouse button (or middle mouse button if you have one) with Ctrl key pressed and held: pans the material preview window. Select Reset if you wish to return to the default display position.

Changing Shape

Would'nt it be nice to have the ability to show certain materials on a different shape than a sphere? Let's change the sphere into a cylinder and save that for future use.

Each of the different preview types has it's own small project file, which is located in the Realsoft3D/previews subdirectory.  It is possible to just load one of them in the same way as any other project. Before continuing, you may want to back-up your previews directory, just to be safe.

To load a preview as a project, select  File -> Load and browse to the previews directory. Select and open the 'denim.r3d'  project. When the Load File requester pops up, click OK. Note there is no thumbnail for this project, so the thumbnail preview window is black.

All the different material preview types               Denim.r3d selected

After loading the project file, you can see it is a simple project with some lightsources, a textured sphere, a textured rectangle and a wireframe invisible backdrop. To change the appearance of our material preview, we simply need to exchange the sphere with a different object, in this case a cylinder.

Make sure you use the wireframe display mode. To ensure the original sphere and the cylinder are about the same size, take a top view and then drag and drop the sphere from the Select Window in the View window. This puts the sphere in the center of the view. Click the Analytics tab, click on the cylinder icon and make a cylinder, at the same position as the sphere and with the same diameter as the sphere. Then take a front view and extend the cylinder, so that it becomes the same size as the original sphere. Note that the new cylinder is added at the bottom of the hierarchy. Now to replace the sphere with the cylinder, drag and drop the cylinder in the preview directory of the hierarchy. Place the cylinder directly above the Preview map object and then delete the sphere from that directory.

Original hierarchy                        Cylinder added                       Cylinder has replaced the sphere

Basically you now have a new project, so if you want to use that project again in the future, you will have to save it under a new name. Because it's a preview project, it must be saved in the previews directory again. Select File -> Save as from the menu and change the name of the file to previews/cylinder.r3d  for example. If you wish to change the user information and the file comment, click on the black preview window. This updates the user information in the file save requester. The comment has to be changed manually. Note that the black preview is exchanged for a screenshot of the current project. When done, click OK to save the project file. Then select File -> Close to close the project. 

Information in the Save requester updated         and the updated material preview.

Next time you open the material property window, you can select the new cylinder type preview from the pop-up menu. The cylinder shows in front view and you must zoom out a little and rotate the view a bit to make the cylinder fully visible.

If you like to see displacement in your material previews, then the analytic object needs to be replaced by geometry that supports displacement, like SDS and NURBS.

In a similar way you could change the mapping type if you like. Simply exchange the Preview map with a different mapping type, like sphere or cube. But for most cases the original parallel mapping type suits best.

Changing the material preview size in the Material Property window

The material previews are 50 x 50 pixels by default, but with today's faster machines, and when working with certain projects as well, you might want to increase the size of that preview render.

Before this method is listed, it should be mentioned that the material preview 'list' in the Materials tab of the Select window, are actually a copied images of the real material preview render. So, if your material preview render is set to 50 x 50 pixels, and you set the image size in the Material tab of the Select window to 100 x 100, you will see pixelisation, obviously.

OK , so go into File/Preferences to open the Options window. Then select:
Graphical User Interface / Gadget / List property Gadget / Material Gadget.

Graphical User Interface / Gadget / List property Gadget / Material Gadget selected

When you have clicked the Material Gadget entry, you will see a list of options appear on the right.

PreviewWidth currently shows a value of 50. Change that to 100.

Click "PreviewWidth". It's current value is set at 50, now change that to 100. Then click "PreviewHeight" and change that to 100 as well. Then close the Options window. The new option settings are activated immediately. There is no need to save a new startup-file.

Now go back to the Material tab in the Select window. Note that seemingly nothing has changed. Double click for instance at the brushsteel material icon to bring up it's Property window . Check the "preview" box and when Realsoft3D does a preview in the window now, you'll see a good quality 100 x 100 render of this material.

A beautiful 100 x 100 pixel material preview render!

Changing the material preview size in the Materials tab of the Select window

To change the display of all your materials in the Materials tab of the Select window to something more than 50 x 50 pixels, open the File/Preferences. This time select:
Graphical User Interface / Gadget / Material Preview List and on the right at top you'll again see two size options, called ImageWidth and ImageHeight.

Graphical User Interface / Gadget / Material Preview List selected, showing
ImageWidth and ImageHeight on the right.

Click ImageWidth and change it to 100, then change ImageHeight to 100 as well. If you would have skipped the previous step  (changing PreviewWidth and PreviewHeight) then the aforementioned pixelisation will occur.

Pixelised material display occurs if ImageWidth        Here you go! Nice smooth big material previews!
and ImageHeight have larger values then
PreviewWidth and PreviewHeight

To fix the pixelised display, make sure ImageWidth, ImageHeight, PreviewWidth and PreviewHeight have the same values. Then close and restart Realsoft3D, then simply click on a material and let Realsoft3D re-render the preview image. You will see an updated Material display in the Select window.

Like mentioned earlier , you could have a landscape project placed in the 'previews' directory and then set the preview render to 200 x 200 and bingo ! Super fast previews of all kinds of materials on a terrain , simply by selecting that landscape preview ! (right click on the material properties preview render and select landscape from the pop-up menu).

Final note: the selected material preview project is a material property, not a window property. Every time you edit a new VSL material or a material that has no custom preview selection, the program loads the preview project called 'material preview'. The user can customize and save it to get a new kind of default preview setup.

      I know you can easily come up with much more elaborate and interesting creations of your own . Hopefully this simple tutorial will help you to get started . Cheers !
  Garry Curtis