File list

File link	Description
Required textures	The custom textures used in this tutorial
End result	The end product of this tutorial for you to examine and compare.

Introduction

In this section, we will cover how to set up an object to use custom textures in Blender, and then how to transfer this into Halo, so that our custom object looks presentable. It is highly recommended to read over the Halo 3 Materials page, as the naming conventions and how materials in Blender correspond to shaders in Halo can be a little confusing to those unfamiliar with it. However, a short explanation will be provided below.

Apply custom textures/materials in Blender

You will need the custom textures from the file list at the top of the page for this section. For the purpose of demonstrating how to use multiple materials on a single object, we will be using a simple tiled wood-effect texture for the top face of our model, and a concrete texture for the sides and bottom.

Adding textures

1. Select the Cube object in the Outliner, and navigate to the materials tab. If you have been following along, you should already have a material named material applied to the object:

   

2. Rename the material to wood.
3. Add a new material named concrete to the Cube object.
4. Now we need to assign the textures that you have downloaded to these materials. Make sure Use Nodes is checked in the Surface section of the material.
5. Assign an image texture node to both of these materials, making sure to navigate to and select the right texture for the right materials. concrete_seamless_texture_6820 is for the concrete material, and parquet_seamless_texture_4264 is for the wood material.

You should now have two materials on the Cube object, both with different textures assigned. Check that your materials tab looks similar to this:

Assigning materials to faces

In Blender, material assignment is done per face on a mesh. As such, we can apply different materials to different faces on our Cube mesh, to vary the look and make it more complex.

You may be wondering why nothing appeared to change when you added the textures to the materials - this is because we are still in Solid Viewport Shading mode. To see the textures on our object, we must switch to Material Preview Viewport Shading mode. This can be done by pressing Z and switching the mode, or by pressing the viewport shading buttons in the top right of the 3D viewport. You can read more about this here. Once you have done this, your Cube will look like this:

After taking a look around the model, you will notice that all sides are using the wood material, and our concrete material is going completely unused. We will now assign the concrete material to all but the top face of the model.

1. Select the Cube object.
2. Change context mode from object mode to edit mode.
3. Make sure you are in face selection mode so that you can properly select the object faces.
4. Select all faces of the Cube except for the top face.
5. Select the material named concrete from the materials list in the object.
6. Click the assign button.
7. To make sure you have the wood material applied to the top face, select the material named wood and assign the material only to the topside face of the object.

You should now have a Cube object with a wood texture on top, and a concrete texture on the rest of the sides:

UV mapping

UV Mapping is the process of projecting a 2D image onto a 3D model's surface. That may sound scary if you haven't encountered it before, but it will begin to make sense when you actually do it. As of right now, you will notice that the wood texture on the top face seems a little too "zoomed in", especially given the scale it will be in Halo. Also, the texturing on the sides of the object is very stretched, which is quite ugly. UV mapping will allow us to solve these issues and make the texture work on the model much more presentable. If you are a complete beginner to 3D modelling/texturing or Blender, and find UV mapping to be too complex at the moment, you are free to skip this section, but the textures on your model will not look very good.

1. Start by switching from the Layout workspace to the UV Editing workspace in Blender using the tabs along the top of your screen

   

2. Hover your mouse over the 3D viewport on the right side, press Z and select Material Preview so that you can see the textures again.
3. Make sure that the context mode of the 3D viewport is set to Edit Mode, and that you are in face select mode

This is the default UV Editing workspace. The left window is the UV Editor, and the right window is the 3D viewport that you are used to from the normal Layout workspace, however it is possible to customize the window positioning to whatever you would like. It is difficult to do such a complex topic as UV editing justice via a text tutorial, so please watch this short UV editing basics tutorial for a visual demonstration on how manipulation UV mapping affects how textures are displayed on a 3D object.

Using the information shown in the video, follow these steps:

1. In the 3D Viewport, select only the top (wood) face of the object. You should see the texture appear in the UV window, along with a small square representing the area of the texture that the face is sampling the pixels of. We want to increase the size of this square so that the face covers a much larger texture area.
2. Hover over the UV editing window and press S to scale the face. Press 10 to scale by 10x in the X and Y axes, and press Enter to confirm. You should see that the wood texture on the object is now smaller, and the tiling is more apparent. This will look much nicer in-game compared to the UV mapping we had before.

   

3. In the 3D Viewport, select only the bottom concrete face of the object. You will notice the texture appears quite pixelated, despite the texture file itself being quite high-res. This is because the UV map for the face isn't large enough.
4. In the UV editing window, press N to open the sidebar if it is not open already, and on the Image tab, set the UV Vertex for both X and Y to 0.5. This will centralize the UV in the center of the texture.

   

5. Next, press S to scale the face, and then type 3 to scale by 3x in the X and Y axes, making the texture appear much nicer on the bottom face.
6. Lastly, we need to sort out the stretching on the concrete textures on the sides of the model. In the 3D Viewport, spin around the model and select only the 4 side faces (remember that you can hold down Shift to select multiple faces).
7. Press the UV pill menu, select Smart UV Project. Set the Angle Limit to 66 degrees. Keep the other options at 0, make sure Correct Aspect is checked, and Scale to Bounds is unchecked. Hit OK.

   

8. In the UV editing window, change the UV Vertex option in the siderbar from 0.250 to 0.5 to center the faces.
9. Next, hovering over the UV editing window, press R, then 90, then hit Enter to rotate the UVs 90 degrees. We must do this so that when we scale, the texture wraps on the X axis and not the Y, as the texture only tiles cleanly on the X axis.
10. Finally, press S, X, 10, then hit Enter to scale the UVs by 10x on the X axis.

This is the end of the UV mapping section, and hopefully your object's textures look much nicer as per the images below. You can now return to the Layout workspace tab. If you are confident with UV mapping or simply want to play around more, feel free to further edit the UVs to your liking, it won't affect any future parts of the tutorial.

Updating the render model in-game

1. Now that we have successfully added two materials to our custom platform and fixed up the UVs, we need to re-export from Blender to .JMS so that we can bring our updated model into Halo 3. If you have forgotten how to do this, read through the steps again in the previous tutorial. As this is the second time we are exporting, you won't need to create a render folder again. Simply overwrite the existing custom_platform.JMS file.
2. Once this is done, we need to run the tool render command again, to re-import the .JMS file. When this happens, tool automatically updates/overwrites the old .render_model tag, and the model will automatically reload itself if you happen to have Sapien open at the same time, which is very useful. If you have forgotten how to open the command prompt in the H3EK directory so that you can enter tool commands, revisit this section from last time. The command we need is the exact same as last time: tool render objects\scenery\custom_platform draft

Your object's render model has now been updated. However, it still won't have any texturing in Halo 3, so it can be difficult to tell if it worked. However, if you happened to keep an eye on the model in Sapien before and after re-importing it, you will notice that the placeholder texture it has will have moved slightly, due to the new UV mapping.

Importing image textures into Halo 3

Similarly to .JMS files, tool.exe will only import texture files from inside the H3EK\data folder. Whilst it will import textures from anywhere within here, it is good practice to put your .tif files into a folder named bitmaps, within your model's main folder.

1. Create a folder named bitmaps in H3EK\data\objects\scenery\custom_platform
2. Copy both .tif files from this tutorial's .zip download to the new bitmaps folder. For example, you should have H3EK\data\objects\scenery\custom_platform\bitmaps\concrete_seamless_texture_6820.tif
3. Open command prompt inside the H3EK folder, as we need to import the textures with a tool command.
4. Enter the tool command tool bitmaps objects\scenery\custom_platform\bitmaps. If successful, you should see the following output:

   

Your textures have now been imported. Halo stores images in a tag type called .bitmap. Think of a .bitmap tag as a container for one or more images. Your newly generated bitmaps, like with the render model, will have been saved the mirrored file location in the tags folder. For example, in this tutorial, the bitmaps get saved to H3EK\tags\objects\scenery\custom_platform\bitmaps.

Creating and applying shaders

Shader information

Shaders are, within the world of Halo, what actually gets directly applied to faces of models and levels. They reference .bitmap tags in order to use textures, and support many shading features such as bump maps, height maps, specularity, self-illumination, color-change and more. If you are familiar with 3D modelling programs such as Blender, .shader tags are essentially the equivalent of Materials in Blender.

Simply having the textures imported as .bitmap tags is not enough to have them appear on our custom model, and we will need to create two basic shaders, one for the wood texture, and one for the concrete texture. As explained previously, when importing a render model, tool looks for corresponding .shader tags with names that match the names of the materials used in Blender. For example, as we named our materials in Blender wood and concrete, tool looks for shaders called wood.shader and concrete.shader. It looks for these shaders first within a folder named shaders within the model's tag folder. In our case, tool will be looking for them in H3EK\tags\objects\scenery\custom_platform\shaders. Therefore, the final step we need to do in this tutorial is create these two shader tags. If you wish to refresh your knowledge on this system, or look at more advanced stuff like shader collections, review this page.

Creating shader tags

1. Open Guerilla
2. Press Ctrl + N. Select shader from the dropdown, or type shader until it appears, then hit Enter.
3. If you are new to Halo shaders, this tag may look horrific, but we only really need to change one option to get our textures on the model. I won't be going over more advanced shader options here, as this is a basic tutorial.
4. Look for the entry called base map under the ALBEDO block. This is where your normally put any base texture that you want for the shader. Click the ... on the right next to it and browse to H3EK\tags\objects\scenery\custom_platform\bitmaps. Double-click concrete_seamless_texture_6820.bitmap to add it to the shader.
5. Now we need to save this shader tag. Press Ctrl + S, and navigate to H3EK\tags\objects\scenery\custom_platform. Create a new folder here called shaders. Make sure to spell it exactly as shown.
6. Navigate inside the new shaders folder, and save the tag here, with the name concrete (remember how this needs to exactly match the name of the material in Blender).

   

7. Usually, tool compresses any imported textures, and this can look to them looking a bit green and low-res. To fix this, double-click on the name of the bitmap tag within your shader, and a new window should pop up for the concrete bitmap.
8. Near the top, change the Curve Mode option to Force Pretty, and the Force Bitmap Format option to Best Uncompressed Color Format. Press Ctrl + S to save the bitmap tag. It should look like this:

   

9. Bitmap tag options don't actually get applied to the image until you re-import the bitmap (since it is too late, it has already been compressed etc). The bitmap tag editor in Guerilla contains a handy button for it, so you don't need to manually enter a new tool command. Press the Reimport Bitmap button right near the top of the window. Try to ignore any warning or error lines in the new window that pops up, and focus on making sure that one of the lines says 1 bitmaps imported as 'Diffuse Map' (in-game size: 33930784 bytes) or similar. If it does, this has worked, and you can close this new small window that has appeared.

   

If you have saved all of the changes in Guerilla, you have successfully made the shader tag for the concrete! You will now need to repeat the previous 9 steps again, but this time making a new shader tag called wood, and saving it into that shaders folder. Once this is done, we can go to the final step of this tutorial.

Re-importing the render model

Unfortunately, adding new shader files does not mean they get automatically picked up and used by the object that needs them. In order for an object to use newly created .shader tags, you simply need to re-import the object's render model once again, to let tool find and assign the shaders.

1. Open CMD in the H3EK folder
2. Just like earlier, run the tool render command to re-import our render model .JMS file. For this tutorial, use tool render objects\scenery\custom_platform draft.

If you don't have it open already, open Sapien and place down your custom platform scenery object! It should now have all of the textures correctly applied to it. If you can't remember how to add or place objects in Sapien, review this part of the previous tutorial. Your model should hopefully look something like this:

Not a bad looking first model! If something has gone wrong and you would like to check my source files and tags, feel free to grab the files from the link at the top of the page

Acknowledgements

Thanks to the following individuals for their research or contributions to this topic:

• General_101 (Original explanation on how materials correspond to textures/shaders in Halo 3, YouTube videos showing several of the processes involved.)
• PepperMan (Writing this guide)