BlitzCoder - Blitz Basic Game Development Resources

Blitz3D Newbies: Max LightMap Baking and the 2 UVW by TigerZ (Hau Nghiep Phan)

Introduction:

So you created this really nice model, or level in 3D Studio Max, but it doesn’t export all your procedural textures into B3d? Well have no fear, Tiger is hear! Currently theres different level editing software that will generate lightmaps for you such as ‘Maplet’, but for some of us, those tools aren’t enough, you want radiosity in Max, you want everything that you can do in Max to be exported into your game engine. So heres an overview of the steps:

1. From Max, you bake the textures
2. From Decorator, you import the 2 UV coordinates *this step is optional*
3. From Blitz, you load and play

Required:

Step 1

Ok, so after you finished texturing your model, you’re now ready to bake the texture. Ill do this with one object, some step might seem redundant but it will be much easier for you to follow, but as you get more experienced, you can find faster ways of doing this.

a. Select the object
b. Assign a new UNWRAP UVW modifier to the object
c. Change the map channel to 50
d. Click on EDIT
e. Click on an empty spot to unselect any faces
f. Click on MAPPING
g. Select FLATTEN MAPPING
h. Let on default setting, click OK

You have now assigned an automatic UV unwrapping of the object, I prefer doing this manually so that I can change the UV manually later on if artifacts appear. You are now ready to bake the texture.

a. Click on RENDERING
b. Select RENDER TO TEXTURE
c. Click on ADD
d. Choose COMPLETE MAP
e. Set your texture resolution, 512x512 is fine
f. Change the channel to 50
g. In ‘General settings’ make sure that Automatic Unwrap Mapping is OFF
h. Click on RENDER

You have now baked the texture, wasn’t too hard was it? Now we need to export it into .3DS file format, if you try it now, it wont work, reason is because the .3DS format has some limitations. It does not export filename greater then 8 character long, so rename your lightmap texture to something like: COMPLETE.TGA. Second of all, it doesn’t export channel 50, so we need to change that.

a. In the object modifier, select the Unwrap UVW that we previously added
b. Click on SAVE
c. Give it a name
d. Add another Unwrap UVW modifier
e. Change Channel of this new modifier to Channel 1
f. Click LOAD
g. Get the saved file

Now you can export the object as .3DS format. So export it, and make sure that your .3DS and the baked texture are in the same directory.

Step 2

*** This is optional, this will let you export 2 UV coordinates if you need it to *** This is extremely easy. You’ll need to export two .3DS file of the same object with different UVW set at channel 1, this is very important that its channel 1 on both file.

a. Open Decorator
b. Load your first UVW .3DS file
c. Press F4 (press G if you want to stop falling down)
d. Load your second UVW .3DS file
e. Press F9 or F12 to export into .B3D file

And that’s it.

Step 3

Well its almost over… now we load the textures and model into Blitz 3D.

a. Load your textures and model
Trunks = LoadMesh("Models\Arenas\Arena_Earth_3\Trunks.b3d”) Bark_texture = LoadTexture("Models\Arenas\Arena_Earth_3\bark.jpg") Shadow_Texture = LoadTexture("Models\Arenas\Arena_Earth_3\S.bmp")
b. Set the 2nd texture to use the 2nd UV coordinates, remember that it starts counting at 0:
TextureCoords Shadow_Texture,1
c. Texture your model and set the index to the proper UV coordinates:
EntityTexture Trunks,Bark_texture,0,0 EntityTexture Trunks,Shadow_Texture,0,1

And done! Not hard eh?

Conclusion

Yay! Another tutorial done, hope this one was helpful.

TigerZ

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