Tutorial 5: Creating and Editing Environment Tags Using Halo 2 Guerilla

Strictly speaking, your environment does not need any .shader files, but without them you won't have any textures. Also, you can have numerous .shader files to specify different shaders for your environment, but this tutorial will only demonstrate a simple one, appropriate for a floor in your sample level.

Note: Keep in mind that whenever you're working in Halo 2 Guerilla, you're working in the \main\tags directory, which is a mirror of the directory structure contained in \main\data.

To create and edit a shader file

1.      Start Halo 2 Guerilla.

2.      On the File menu, click New.

A dialog box appears, asking what type of file you want to create.

3.      Click Shader in the list, and then click OK.

A nearly empty window representing the new file appears.

4.      Before you can specify what the shader looks like, you need to select a shader template, which defines what basic type of shader you're creating. There are many templates to choose from, but typically you just want an opaque surface with a bump map and possibly a detail or environment map. The functionality of a given template is loosely explained by its filename.

To select a template, click Browse to the right of the same line as the template is printed.

The Select File dialog box appears.

5.      Browse to the Halo 2 Tools installation folder and then to tags\shaders\shader_templates.

You'll find several folders with different types of templates, but you just want a floor texture, so open the opaque folder.

You should now be looking at the contents of tags\shaders\shader_templates\opaque.

These opaque files have numerous small differences, but for your purposes select tex_bump.shader_template. This is an opaque template that allows you to specify a diffuse map (color), a bump map (surface relief, bumps, and so on), and a detail map (a sort of noise that adds fine grain to the surface in the game).

After selecting tex_bump.shader_template, click Open.

6.      A lot more fields are now available for editing. You will want to fill in four of these for this tutorial.

First, click Browse next to base_map.

The Select File dialog box appears.

7.      Make this a concrete texture by browsing to an appropriate .bitmap file, which will provide the image format the Halo 2 game image uses, so any textures you want to use in a shader need to be in that format. They're created using Halo 2 Tool.

Use the concrete texture from Zanzibar. Browse to tags\scenarios\bitmaps\multi\zanzibar, select basic_concrete.bitmap, and then click Okay.

The base_map line now has basic_concrete listed.

8.      Because the base map is just the colors of the surface, you'll want to give it some relief. This is done using a bump map, specified in the line labeled, appropriately enough, bump_map.

Click Browse next to bump_map, select basic_concrete_bump.bitmap in the same folder, and then click Open.

Now you have a texture with both color and the appropriate bumps and ridges.

9.      When you zoom into your map, you’ll want it to show appropriate graininess. For this you’ll use a detail map.

Click Browse next to detail_map, browse to tags\scenarios\bitmaps\detail_maps\concrete, click concrete_pitted.bitmap, and then click Open.

The concrete_pitted file is now listed as your detail_map.

10. Finally, you need to scale down the detail map; otherwise, it will be the same size as the other maps and its detail will be lost. You'll notice several scale fields listed for all the maps, although generally you'll only want detail to be scaled differently than the others. (There are many tricks you can do by editing the other fields once you become accustomed to working with shader files.) In this case, you want the detail map to be scaled much smaller than the other maps.

Click f() to the far right of detail_map_scale_x.

A dialog box with a number of fields in it appears. The one you want to edit is just below Input, and by default it shows 16. This is a little too small (the number dictates how many times this texture tiles for each time the base texture does).

Type 6 in the Input box, and then press the ENTER key.

You will now see the value 6.00 listed next to detail_map_scale_x.

Repeat this step for detail_map_scale_y.

Your shader file is now complete.

11. To save it, click Save As on the File menu.

The Save File dialog box appears.

12. Typically you'll want to save new shaders in a folder named after the level they'll be used in. Assuming your level is called MyLevel, browse to tags\scenarios\shaders\multi\MyLevel, and then click Open.

You will now be viewing the contents of your tags\scenarios\shaders\multi\MyLevel folder.

13. Name your shader file concrete.shader, and then click Save.

To use your new shader file

Your shader has been saved, but you can't use it in a level quite yet. Before that happens, you need to create a new shader collection for your MyLevel folder. A shader_collection file is a text file listing a collection name (used in your material name in your .max file) and the path that the collection refers to. Generally, you'll want to name the collection after your level, to avoid conflicts with any other levels' collections.

1.      Start Notepad.

2.      You need to add two fields: The first is your collection's name, and the second is the path to the shaders in your collection. Type

mylev scenarios\shaders\multi\mylevel

This means that when you type mylev into a material name, 3ds Max will use the shaders in scenarios\shaders\multi\mylevel.

3.      On the File menu, click Save As.

The Save File dialog box appears.

4.      Browse to your working folder and then to tags\scenarios\shaders, click All Files in the Save as Type box, type mylevel.shader_collection in the Filename box, and then click Save.

Remember that you can always open a shader_collection file in Notepad and edit it later. You only need to create a new one when you create a new folder for your shaders.

5.      Now that you have a shader collection, you can use your shader file in your level. Begin by opening your level in 3ds Max.

6.      All that's necessary is to change the material name of your material to one using the new shader. If you've opened mylevel, the box map in the earlier tutorial, bring up the material window by pressing M and then selecting your level's Multi/Sub-Object material.

7.      The bottom half of your material window should list all your submaterials. Find the one you're using for your floor, and then click its name to view its properties.

8.      Change the name of your floor material to mylev concrete.

Note that this is the name of your shader collection (from inside the shader_collection file) followed by the filename of the shader you created. Together, these tell the exporter where to look and for what shader filename.

9.      Export your level as you did in the level creation tutorial, and your new shader should be visible.

Note: Remember that you only need one shader collection specified per folder and that you should try to name that collection after your level. Try to pick something unique; otherwise, someone else's collection (or level) might use the same name and things might not work right.