Simple Road Sign 3D Model Creation for STISIM Drive

There might come a time when you need to create a new 3D road sign, or modify an existing one, in your STISIM Drive simulator. The good news is this is something you can absolutely do on your own, and we’ve outlined the process below to get you on your way.

There are several different ways to create and modify road signs, only differing in their complexity and the tools needed to accomplish the task. Obviously the more complex methods produce the best results but also require the most time, the best tools, and some modeling knowledge.

The techniques described here do not require any special 3D modeling software and there are free versions of the software needed to accomplish this task. Though we’re only going to focus on the creation of road sign models, the techniques we talk about could also be used for creating other 3D models.

Tools Required for Creating 3D Road Signs

To apply the techniques discussed here, you’ll need these tools:

  • Image modification software (paint program). This will be required to create the new artwork that you will apply to your sign. Some free applications that you can use for this purpose are:
    • GIMP
    • Paint.Net
    • Microsoft Paint (you can find this in the Windows Start button/All Programs/Accessories/Paint)
  • Binary Editor. This will be necessary to modify the existing 3D model file with a new material name. The editor must be able to edit files in binary mode (on a byte level) so programs like Windows NotePad will not be sufficient. Try one of these:
    • NotePad++
    • Another good but not free editor is UltraEdit, although you can download a free trial of the software
  • Text Editor.  This will be used to modify the text based material files. Most binary editors also allow you to edit text, so the same editor that you chose in #2 should work here. Otherwise, you can always just use Windows’ NotePad or WordPad for text editing.

What You Will Need from STISIM Drive

First a little background before you get started. The 3D models that you see in the STISIM Drive roadways are generally comprised of three different resources, each contained in its own separate file:

  • 3D Model File – This contains the physical geometry of the 3D model that is shown to the driver.
  • Artwork Files – These files contain the images that are applied to the 3D model file and are what make the 3D model look realistic. The artwork could be contained in a single file or multiple files depending on how the 3D model was created.
  • Material Properties File – This file contains information on what artwork will be applied to the 3D model and defines characteristics on how the artwork will be applied. Characteristics such as artwork resource (file name), lighting, etc. are contained in this file.

To modify an existing 3D sign model, you will most likely have to make modifications to all three of these resources.

  • 3D model file that you would like to use as the basis for your changes. A complete list of resources that are provided can be found in the Model Library Manual. Pay particular attention to the file type (listed in the header of each model category or for each individual model) and the model file path (listed in the header for each model category). Only files of the type MESH can be used in this process, and the file path will show you where you can go to find the MESH file.
  • Material file that contains the individual materials associated with a model. In general, STISIM Drive has one material file per model category and it is in the C:\STISIM3\Data\Materials folder. For road signs the materials are in the RoadSigns.Material file.
  • The artwork that goes along with the 3D model. In general, the artwork is in the same folder as the MESH model, however if it is not found there it may also be located in the C:\STISIM3\Data\Textures folder.

How to Create Your 3D Road Sign

Sure, this process requires a number of steps and different applications in order to complete, but once you get used to it, you can create new signs in a matter of minutes. Plus, we’ll walk through an example at the end.
Before doing anything else you will need to choose and prepare the original files that you will be modifying to create your new model.

  1. Find the files associated with the 3D model that will be changed. You can look at the Model Library Manual to help determine what model to start with and then navigate to the folder that holds the model resources. Look for a model that currently has the shape of the sign you want to change and start there.
  2. Copy the files to a new temporary location so you can modify them without damaging the original files. Remember you will want to copy the MESH file, the MATERIAL file, and all the artwork (texture maps, pictures, etc.) associated with the file.
  3. Rename the 3D model’s MESH file and the artwork files to descriptive new names. You will not need to rename the material file because you will be adding a new material to it. However, if you are worried about messing up the current material file, you can simply use your text editor to create a new empty (blank) material file.

The first (and generally most time-consuming) step is to modify your artwork (texture maps, pictures, etc.). This is where you’ll need the paint program we mentioned earlier. Take your new copy of the original artwork, load it into the paint program, and modify it to meet your needs. You may also want to look online and see if you can find artwork that already exists – if so you can simply download it to this folder (and save yourself some time).

Because you may want to use the original model as well as your new model, you will need to create a new material and include it in the material file.

  • Figure out what the name of the material is and find it in the material file. There are a couple of ways to do this:
    • You can open the 3D model’s MESH file with your binary editor and find the name of the material.
    • If you have the name of the original art work, you can open the material file and search for the artwork. When you find the artwork, you can then determine the material name.
  • Once you have found the material, use your text editor to open the material file and copy the desired material and paste it into at the bottom of the file, or to your new material file.
  • Then, rename the new material that you pasted in step 2. VERY IMPORTANT: The new material name must have the exact same number of characters in its name as the original material. For example, if the original material name was Sp00Mph.3ds/SPEED_LIMIT_00, then the new name that you give the material must have exactly 26 characters in it.
    In your new material definition, you will also need to change the name of the artwork that will be used. For example, if the original material used the file SpeedLim.Jpg, you will need to change this to MyNewSpeedLim.Jpg (or whatever the artwork file is that you created).
  • Save the material file.

The final step in the process is to modify the 3D model’s MESH file so that it points to the new material that you created.

  1. Using your binary editor, open your new MESH file.
  2. Search through the file to find the name of the old material (this is the name that you previously modified to create the new material name).
  3. Change the original material name to the new material.
  4. Save the file.

The final step is to copy the files that you modified back into the original folder that they came from. And, voila! You now have a new sign that you can use in the simulator scenarios!

A Practical Example

The best way to illustrate this process is with a practical example. In this case we will be changing the way a rectangular speed limit sign looks. Here is the process:

  • Go to the C:\STISIM3\Data\Signs\Speed Limit folder;
  • Copy the files Sp55mph.mesh (MESH file) and Sp55mph.jpg (artwork file) to the C:\STISIM3\Temp folder;
  • Navigate to the C:\STISIM3\Data\Materials folder and copy the RoadSigns.Material file to the C:\STISIM3\Temp folder;
  • Go to the C:\STISIM3\Temp folder;
  • Rename the MESH file as Sp55mph_New.mesh;
  • Rename the artwork as Sp55mph_New.jpg;
  • You should now use your paint program to modify the Sp55mph_New.jpg file so that it appears the way you want. For this example, we will simply change the color of the characters on the signs:

The color of the sign text goes from black to red and green.

 

  • Save the new artwork file.
  • Since we know the name of the artwork (Sp55mph_New.jpg), use your text editor to open the MATERIAL file and search for Sp55mph.jpg;
  • When you find the reference to this file, highlight and then copy the entire material. You want to go up from the line texture Sp55MPH.Jpg until you find the word material followed by a name. It should look like this:
material SpeedLimitSignsTextures/55MPH
{
	technique
	{
		pass
	{
			texture_unit
		{
				texture Sp55MPH.Jpg
		}
		}
	}

	technique
	{
		scheme FR_stencil
		pass
		{
			texture_unit
			{
				texture Sp55MPH.Jpg
			}
			vertex_program_ref phong_1UV_fog
                    {
                    }
                    fragment_program_ref stencil_BP_fog_decal
                    {
                    }
		}
	}
}

  • Scroll down to the bottom of the file and paste the material into the file;
  • You will now need to rename the new material with some unique name that contains the exact same number of characters as the original name did. The original material’s name was SpeedLimitSignsTextures/55MPH which has 29 characters and therefore the new name must also have 29 characters. For this example, the new material name will be SpeedLimitSignsText/55MPH_New. Remember this new name, it will be needed shortly.
  • Save the MATERIAL file;
  • Using your binary editor, open your 3D model’s MESH file (Sp55mph_New.mesh);
  • Search for the original material name (the one from the original file, in this case it was SpeedLimitSignsTextures/55MPH;
  • When you find the original material name, change it to the new material name that you just created SpeedLimitSignsText/55MPH_New:

    Replace the original material’s name….

    …with the NEW material’s name.

  • Save the changes you made to your MESH file;
  • Finally, copy all the files that you changed from the C:\STISIM3\Temp folder back into the C:\STISIM3\Data\Signs\Speed Limit folder.

You should now be ready to use your new speed limit model sign in the simulator.

Happy Driving!