• Background Information
• Limitations
• Getting Started
• How to Blender
  
  • Object Mode
  • Edit Mode
  • Materials
  • Textures
  • UV Mapping
  • Modifiers
  • Animation
  • Vertex Colors
  • Armatures
• Preparing for Ikemen
• Baking Animations
• Skyboxes
• Baking Lightmaps
• Exporting to GLTF
• Using GLTFs in stages
• Troubleshooting & Common Blender Questions
• Miscellaneous Tips
• Further Reading
• Special Thanks

• There is no direct support for light objects or environment maps. However, you can get around this by pre-rendering (or "baking") your lights beforehand and creating a skybox respectively; we'll touch on this later.
• Related to the above, Ikemen does not currently use any part of a material other than the color map, so no roughness, metallic, specular, normal, emission, etc. are displayed.
• Armature deformations/weights are not supported. This means that, while models with armatures will be drawn, they won't animate and will most likely default to their base pose. Update 12/26/2023: Armatures are now supported in the latest nightly builds!
• Volumes/volumetrics of any kind are not supported, which means that things like fog will have to be simulated with a bunch of transparent planes.
• Currently, only PNG, JPG, and uncompressed DDS textures are supported. Draco compression is also not supported.

• Blender: A very well-known free and open-source 3D modelling program. This is what I'm going to be using for this guide, and it's most likely what you'll want to use unless you happen to have a copy and familiarity with other programs like Maya or 3Ds Max. I'm using version 3.4 here, but the general workflow should be more or less the same across all versions past 2.8. [Editor's note: Blender 4.0 released right in the middle of me writing this guide, so if the UI looks slightly different for you than what I'm showing here, that's why!]
• Rodzilla's Material Maker: Also free and open-source, this program makes it easy to create procedural, seamless textures for use with 3D models. I used it to create the textures in my original stage, Third Heights.
• If you don't want to make your own textures from scratch, ambientCG.com has thousands of textures available as CC0/public domain, mostly photoreal ones. Ditto for polyhaven.com. I'd still recommend making your own if you can though!
• Either GIMP, PhotoShop, Paint.net, or some other image editing program. Not strictly necessary, but it's very handy to have on hand for editing textures. (Blender has its own image editing tools built in, but I find them to be clunky personally.)

Note: Due to MFG post size limitations, I'm not able to include the How to Blender sections in this post. I've split them into two replies to this thread. Click the respective section to be taken to the reply containing it:

• Object Mode
• Edit Mode
• Materials
• Textures
• UV Mapping
• Modifiers
• Animation
• Vertex Colors
• Armatures

Okay, now that I've given all the newcomers a crash course on how to use Blender (or at least a subset of it), I can FINALLY start talking about the fun stuff specifically for Ikemen. As will become evident in a second, from this point on I'm assuming you have decent knowledge of how Blender works, beyond what I've covered here already.

First off, make sure that the origin of the world (coordinates {0, 0, 0}, where the grid axis lines all intersect) is aligned with where you want the fighters to be standing. If you need to adjust the position of the scene, hit A to select everything, then G to move it into place. This part is pretty crucial, so make sure to get it right!

Next, make sure the scene itself is oriented properly. If you press Numpad 1, you'll be looking in the direction that Ikemen's 3D camera will be looking towards. Make sure your scene looks correct when viewed from this direction, rotating the mesh if necessary I recommend pressing A, then R, then Z to lock rotation to the Z axis, then rotating it until it looks how you'd like.

Finally, and this isn't as important (as you can adjust the scale of the model in the .DEF later), I'd also recommend scaling the stage to a reasonable size when possible. "Reasonable" is subjective here, but I generally like to keep stages within a roughly 8x8 grid of Blender's "large" grid squares when viewed from above and at a medium-distance zoom. This isn't a hard and fast rule, but it's something I like to do for consistency's sake across various stage models and to make it easier to adjust stage size. The procedure's pretty similar to rotating and moving: A to select all, S to scale up and down, hopefully you get the idea.

Here's an example of what it should look like when its aligned properly and scaled to a reasonble degree:

For the most part, animations should just work as-is, but I've ran into some interpolation issues when exporting animations involving keyframes beyond the start or end of Blender's animation frame range. The solution I've found (warning: this is not reversible, so make sure your animation's how you want it first!) is to go to the Animation workspace, select your keyframes, and then press Shift+Alt+O to sample the keyframes. This essentially "bakes" their animation data by creating a keyframe on every single frame (indicated by blue dots), which allows it to export properly. You may need to manually remove keyframes beyond the animation frame range if you're still having problems, but other than that, it should work after doing this!

As mentioned above, Ikemen does not directly support light objects, and that also includes the environment map. This means, if we don't want a pure black background, we must simulate an environment map using an old-school approach: the skybox (or skysphere if you want to be fancy and use a sphere, but most people still call it a skybox either way). A skybox is a big mesh (usually a cube for performance reasons, but a sphere works great too) that goes around your entire scene and typically has flipped normals, allowing you to look through it on the outside.



To create a skybox, press Shift+A to create a new cube or sphere, then switch to Edit Mode and scale it up to fit over the entirety of the scene. Now press Alt+N (or use the F3 search menu) and look for an option called Flip; click it to flip the mesh's normal direction. Assign it a new material, give it a sky texture, unwrap it so it looks nice, and then here's the important part: in the Material Properties panel, scroll down until you see the Settings section. In there should be a checkmark toggle labelled "Backface Culling"; enable it and you should now have a functioning skybox!

I want to stress: this part is entirely optional, and as you're about to find out, potentially very tedious and time-consuming to do, but worth it for the improved visual quality in my personal opinion (a great saying I heard in the 3D community and also just a good tip for art in general is "90% of art is in the lighting"). I would only recommend doing this if you are paitient and are savvy enough with Blender that you know how to use the node editor and how UV maps work.



Baking your lights means to pre-render your lights onto a new texture map, which is then applied back onto the models, giving you the visual benefits of lighting without having to require the computer to actually calculate said light in real time, which saves a ton on performance. This technique is very common in games, used in everything from Half Life Alyx to Quake to Mario Kart. It's also the only way to get lighting detail out of Ikemen right now, as there's no support for light objects directly at this point in time. Unfortunately, as you're about to find out, it's a pain to do in Blender.

The following instructions are an abbreviated version of this article on Blender Knowledgebase, which is where I learned how to bake lightmaps. If you run into issues, check that page.

So first, you'll need to open the Node Editor tab and add a new Image Texture node to an object's material, with the node not being connected to anything else. Create a new image (the name doesn't matter but I usually call it "Lights" or "Lightmap"), and set the resolution of the texture to a high power of two (I usually use 8192x8192 as that's a good compromise between quality and performance). In the Object Data properties (that's the green triangle tab), create a second UV map and connect that second UV map to the Image Texture node using a UV Map node. Make sure to also select said second UV map if it isn't already, as this will become important in a second.



Now you need to add that same Image Texture node to every single material whose lighting you want to bake, along with creating a second UV map for each object whose lighting you want to bake. You can make this process slightly less tedious by converting all your materials into an atlas (see Optimizations), but it'll probably still take quite some time.

Once you've done that, select all the objects you want to bake, switch to the UV Editing workspace, and enter Edit Mode. Press A to select the entirety of the meshes for all the selected objects, then press U to bring up the UV menu. Select Lightmap Pack and set the image size to the same size as your new texture from earlier. The margin value is kinda hard to explain and you might have to trial-and-error it depending on your meshes, but I generally go for 0.15 to 0.2.



Once your lightmap UV is set up, you must now head back to the Node Editor. Make sure the Image Texture node with the lightmap texture is selected, then go to the Render Properties tab (the gray camera icon) and change your render engine to Cycles. Make sure to set the Device to GPU Compute (as this will dramatically reduce the time it takes to bake), and make sure to disable the Denoise options, as not doing so will result in weird artifacts on the edges of every face of your baked lightmap (I found this out the hard way).



Now that ALL of that preamble is done, save a backup file of your Blender scene, then you can finally scroll down to the Bake section and click Bake. Depending on your hardware, the size of the lightmap texture, and the number of objects/materials you're baking... this could take quite a while. My original Third Heights stage took roughly 8 minutes on an RTX 3060 Ti to bake an 8192x8192 lightmap, so if that gives you any idea of how long it'll take on your scenes, there you go.

Once it's done, you'll then need to set the lightmap UV map to the rendered UV map (meaning the little white camera icon should be enabled for it) for every object, connect the Image Texture node to the Material Output (or Principled BSDF, but preferrably Material Output), and then you should be able to export the model with your shiny new baked lightmap. If it still defaults to the old UV map and your exported scene looks like a garbled mess, you might need to delete the old UV map entirely to get it to export properly; I'm still a bit confused on this myself, frankly.

So now that our model's all prepared and ready to go, it's time to export your creation! To do that, go to File in the menubar at the top of the screen, then under Export, click GLTF 2.0 (.gltf/glb).



A window will pop up asking where you want to save, and on the right will be some parameters you can adjust if desired. If your scene uses Modifiers, make sure to go to Data -> Mesh -> Apply Modifiers and enable it. Aside from that, the default settings are plenty good for most scenes, so navigate to where you'd like to export the file and click Save. The resulting file should, by default, be a self-contained .glb.

It's a good idea to verify everything looks how you'd like first by viewing your exported model file. If you're on Windows 10, you can view the .glb file directly using the built-in 3D Viewer application. Otherwise, you can use web-based tools such as this one from Khronos Group or the aforementioned gltf.report.

So now we finally have our model file, it's time to put it to use! I'm not going to go into detail on how stage .DEFs in general are written, as there are countless guides for that already both here on Mugen Fighters Guild and elsewhere online; for the most part, it's identical to how you'd usually make a stage. However, I will highlight the new stuff needed for 3D stages to display.

The first new parameter is called fov, and it goes under the [Camera] section. This controls the field-of-view of the 3D model. I personally set mine to 30 as that's what Blender uses by default for its camera, but you might want to experiment a bit.

Code:

[Camera]

; (insert other camera parameters here)

fov = 30

The next one is in the [BGdef] section, where you would define the SFF file the stage uses. The SFF is still required to be included by spec (although outside of another Ikemen feature, stage portraits, the contents of the SFF don't really matter much). You can use the parameter model to specify the filename of the model, in a similar way to spr for the SFF:

Code:

[BGdef]
;Filename of 3D model file
;Supported file types are gltf and glb. Texture types supported are PNG and JPEG, no DDS.
;Make sure the world origin of the model is at the camera starting point!
model = stage3d.glb

;Filename of SFF file, required by spec (and for stage portraits!)
spr = stage3d.sff

Finally, to actually use the model in a stage, a brand-new [Model] section has been defined, with the following format:

Code:

; Model element definition; this is similar to the [BG] blocks in 2D stages
[Model]

; X, Y, and Z coordinates of the model
; X = horizontal, Y = vertical, Z = depth
offset = 0, -0.25, -1

; Scale of the model
scale = 0.5, 0.5, 0.5

You may need to tweak the position and scale quite a bit to get it looking correct; a pro tip from me is to use Shift+F4 in Ikemen GO to reload the stage's files without having to restart the entire game, making it easier to test changes.  I recommend creating a temporary plane at {0, 0, 0} and rotating it 90 degrees on the X axis (so that its facing towards the camera) to make it easier to set your offset values correctly.

If your stage was aligned correctly in Blender, you shouldn't need to adjust the X offset much at all. The Y offset I usually keep somewhere around -0.2. As for Z offset, I usually set its value between -0.75 and -1.5, though you might need to dial this value in if you notice your model/characters are moving "faster" than they should. Also, quick note: do not set the Z offset to 0, as otherwise the model's geometry will not move at all. Likewise, setting it to a positive value (above 0) will cause the geometry to move inversely to your characters.

Once all of that is done though, congratulations: You now have a 3D stage in Ikemen!

This part compiles a bunch of common questions I've been asked when helping out others with Blender stuff, and is probably of good value to you folks too!

How do I get transparent textures to display right?
Go to the Node Editor workspace and make sure the Image Texture's Alpha output is connected to the Principled BSDF shader's Alpha input. Then, go to the Material Properties of the material with the transparent texture, and make sure to set Blend Mode to Alpha Clip. You might also need to toggle Backface Culling depending on the model.



How come my model's faces look weird and 'inside-out'-y?
This usually means your model has its normals flipped or otherwise not set correctly. The fastest way to fix it is by selecting the entire mesh in Edit Mode, pressing Alt+N to bring up the Normals menu, and then clicking Recalculate Outside. Blender has a built-in Viewport Overlay option (it's in the down-arrow button next to the icon with the two circles) to display normal orientation as well; blue is facing outside and red is facing inside.



What are some good sizes/model stats for a stage?
In terms of file size: all of the stages I've made so far rarely exceed a .glb size of 20 megabytes. Whether or not that's feasible for your stage depends on what it is and how much detail you want to include; admittedly mine are rather simple in terms of composition, but still. If you feel like your stage's file size is too large, try some of my Optimization tips above.

In terms of geometry/tri counts: I usually try to keep my stages around the 10,000 to 30,000 tris range. That puts it somewhere between a late Gamecube and early Xbox 360 game in terms of mesh detail; this might not sound like much, but a general rule of thumb is that textures carry much more detail than the underlying mesh itself does, so higher poly counts won't really give you much benefit after a certain point.

Speaking of textures, unless you're using a lightmap, my textures for stages don't usually exceed a resolution of 1024x1024. This makes sense as I imagine that most people playing Ikemen are probably not playing at a high-enough resolution for 1024x1024 to seem 'low-quality' (especially since the texture isn't going to be seen at its native size, but rather distorted onto a 3D mesh, thus you'd only be seeing a fraction of its actual resolution).

Why is my 3D stage rendering as solid black?
This can be a few different things. First, make sure you're using a version of Ikemen GO that actually supports 3D models (as of this writing, that means specifically the nightly builds, not 0.99). Secondly, make sure that your graphics drivers are up to date (particularlty for those of you using older graphics cards or chipsets). Thirdly, if it's a stage/model that you've created:

• Make sure that, when exporting from Blender, your image texture is connected to the Principled BSDF node's Base Color input, which is in turn connected to Material Output. Any other BSDF input, such as Emission, won't render anything in Ikemen.
• Make sure that your stage's position and scale are appropriately set in either Blender or Ikemen GO, preferrably the former.
• Make sure your model's normals are facing the correct direction.
• Make sure that your .def file is correctly pointing to the filename of the .glb file you exported, and make sure said .glb is in the correct file location.
• If you added vertex colors to an object, check and make sure they aren't all set to black; for some reason that's what Blender defaults to for the default vertex color.

It's also been observed that those using Windows 11 have had 3D stages not render unless you go into Ikemen GO's properties and set its Compatiability Mode to Windows 10 and/or explicitly set the GPU to use. If you're running Windows 11, give that a try as well!

I'm getting a huge error about nil pointers! What did I do wrong?
As of right now Ikemen GO will crash if a model includes an object that has no materials assigned to it. Make sure that all your objects have at least one material!


Another common cause is when authors erroneously remove or otherwise not include an SFF in addition to the GLTF file. This will cause Ikemen GO to crash due to a missing SFF, so make sure to include one! I'd recommend using the opportunity to make a stage portrait (sprite 9000, 1 in the SFF; you can check Ikemen's included stages as reference for what it should look like).

• As mentioned above, Blender's 2.8 Fundamental series and/or BornCG's Let's Learn Blender are really great series that jog through various aspects of Blender, probably even better than my guide does.
• ExplainingComputers's modelling introduction is also a pretty good introduction to Blender's modelling tools, though it specifically focuses on modelling for 3D printing rather than general-purpose modelling. Runtime of 35 minutes.
• Daniel Kraftt's "Blender Tips You Might Not Know" series. Has multiple installments (I linked the first one), but it's a rapid-fire list of very useful tips and quality-of-life things that might be good to know.
• As silly as it might sound, the built-in tutorials for Mario Artist: Polygon Studio on N64DD are surprisingly still pretty applicable to Blender as it uses fairly similar modelling techniques. Might be worth checking out, even if just for novelty's sake.
• Blender's official documentation is a good resource to have on hand as well, though admittedly I don't use it as much as I should. If you're confused by a specific aspect of Blender, definitely check there.
• There's plenty of communities out there for Blender if you'd like to ask for some help and support with aspects of the program. Blender's website aggregates a bunch of them on this page here.

• Eiton, for implementing 3D stage support in the first place.
• Violin Ken and PotS, for proofreading this guide and giving me some feedback.
• The Blender Foundation for giving us such an incredible 3D tool for free, and making it open source.
• This also applies to its community. Thanks for giving me the resources to get started on 3D stuff myself!

I want to make some animations using, sprites 2D to the background, like cameos watching the fight; how can I do this at the stages?

How come the Moderators are not set a Ping on this very wonderful Guide. for STICKY WE NEED IT :O