Something that makes Megu Shinonome is that you can actually give a gift of 3D model.
This article covers information about how to create one.
Let me, first by introducing what the official website stats:
Number of mesh: 1
Number of polygons: about 5000 (You cannot use N-gons)
Number of materials: 1 to 2
Type: png (4096×4096 pixels)
Only a color texture, and a shadow color texture allowed. You cannot use normal and alpha.
File name of the texture:
Color texture: any name you prefer
Shadow color texture: Color texture name followed by _Shadow1
Include files in a folder with the name pattern of OBJ_XXX (Where XXX represents your object name)
Contents of the folder
・An obj file
・A mtl file
Model should be made in a actual size
If you are using Blender:
When exporting to obj, use 100 as the scale. You can also magnify the object by 100 as well.
Because this converts the model in a centimeter scale, 1x would be very small.
Use a web file transfer service to send the resulting file to @meguart_otayori.Instruction provided in the official Megu Shinonome Website
Note: the English equivalent of the screenshot above is the following:
This instruction contains the all the requirements but many may find it is difficult to start with this instruction. This article will guide you through each process.
This article assumes the following. If you do find any of the following items unclear, it is advised to find some videos or other materials covering these topics. (or you will find yourself lost in the process…)
- General information of how to use Blender (installing, starting, reading writing, using exporters, etc.)
- Basic modeling process. You will need to know how to transform, connect the faces. Of course, if you are to actually create something, you would need some more skills in addition to it.
- Using UV textures. How to use the UV editor, unwrapping mesh. There will not be any advanced usage, so you just need to know the basics of it.
- We assume that you know how to use your operating system, including installing application, how to use ZIP file, etc.
You will need the following. You can get them for free:
- Blender (You can technically use anything that can export an Wavefront OBJ, but these are not covered under this article.) We will be using Blender 2.90.1.
- Krita (or some other 2D image editor. You can use the one that comes with Windows, for instance. You just need to be able to export your file to PNG format. We are not covering how to use aspect of this tool; use something you prefer.)
In addition to that, the following tool made by Makimaki is useful in confirming the correctness and scale of your model.
While Blender supports multiple platform, while the makiMeguAcce supports Windows. Because of this it is advisable to work on Windows platform. Even if you are working on other platforms, I would strongly recommend confirming your model using this tool on a machine running Windows.
You are subjected to some restriction on the parameters when creating a model for Megu. For example, you will have to keep yourself conscious about polygon counts while working on your model. It is useful to have this information up on your screen all the time. (This is implemented in 2.90 and onward.)
To enable this, enable Statistics from Viewport Overlays:
With this enabled, you will see a display like the following:
By selecting a object, or going into edit mode, you will be seeing information about the particular object. It is useful in controlling your polygon count while you are working on your model.
From here you can start modeling. You will need to remember some important restriction in modeling. That is, one object, and one texture. Therefore, it is often easiest by creating a model using low polygon counts, while connecting them together.
The model I have created, used this method, using mirror modifier:
You can also attempt to work it downward from high resolution model, using Decimate modifier, especially when you already have a model you want to use. They tend to introduce unpredictable artifacts, thus, you may have to perform some trial-and-error processes.
You will need make sure to not introduce any N-gons — always use three or four vertices in your faces.
You also cannot use vertex color, nor can you specify multiple materials. Therefore, you will have to apply an UV texture within one material. Because of this, you will have to organize faces of different colors and textures, it is useful to use Vertex Groups.
You can define a vertex group by selecting vertices and press the Assign button.
You can use the Select and Deselect button to select and unselect defined vertex groups.
General process is to create a texture atlas like below, and then assigning region for each of vertex groups as you have defined. This would be, selecting the appropriate region, unwrap it under the UV editor tool, assign the desired portion of the UV texture. Therefore, you will still have to create and define simple color as a texture.
You can use up to 4096×4096 texture.
Define this texture as the Base Color under the material:
There is a shadow color texture within the official specification, which it used to be able to assign texture to AO map in Blender, however this is no longer possible. (Inspecting the exporter code, this is always assigned “None” value, thus this seems to be deprecated.)
If you really need ot use a shadow color texture, you will have to bake this into your color texture.
Checking the Normal
It is important to ensure that your model has the normals that pointing the correct direction. Basically, this needs to be pointing toward out side of your model.
To confirm, use the following option:
You should see the display like the following:
These blue lines show the direction of the normals. If these are pointing to wrong direction, this would be more like following. (You can see the line pointing inward.)
If the normal is pointing to the wrong direction, they won’t be displayed. (Checking this with the MakiMeguAcce tool is discussed later, too.)
To ensure you have the normals pointing to the correct direction, use Recalculate Outside function, which will point the normal toward outward from your model. (Or you can also use Shift-N key.)
If you have part of the models showing the normals in wrong direction, you can select it and use the Flip function from the same menu to switch it.
Exporting your model as an OBJ file
Use the exporter in Blender to export your model as an Wavefront OBJ file.
By selecting this function, you will see some export options:
You will need to make sure OBJ Objects and Material Groups enabled under this. Also specify the Scale to 100. (You can optionally adjust this scaling your model. For more information about this, please see the next session covering makiMeguAcce.)
Once you have set your export options, you can save this as a preset; makes it easy when you will be using these setting later.
After exporting, you should be a OBJ file and a MTL file. Be sure to place your texture file in the same place as you have exported.
Checking with the makiMeguAcce
Once your model is ready and exported in a OBJ file, you can check your model using makiMeguAcce. This innovative tool, created by Makimaki, removes a lot of trial and error, which makes the process more predictable.
You can display the size and texture of your model.
Just drag and drop your object file, and you will see your model displayed like the following (in the example below, “Show Megu” option is enabled.)
Using this, you can confirm your model is showing correctly, as well as the size is appropriate.
Like under Blender, this tool will also show numerical parameters of the model. With this tool, any out of parameter items are shown in red.
If your model has a dark texture that’s unnatural, it is likely you have the normals pointing at wrong direction. (Just like the left side of the following.) You will need to resolve it.
Once you have your OBJ, MTL, and texture file ready, put those files in a folder name starting with OBJ_ followed by your object name, compress it as a ZIP file, and use web file transfer service and notify @meguart_otayori via Twitter. You should get notification once your file is successfully downloaded.
That OBJ_ of the folder name should be uppercase or it won’t be loaded. Be sure to name this correctly.
Also, you will have to use Japanese to communicate @meguart_otayori. See below for more information on this.
It is definitely interesting experience that Megu wears and play with your models, and I like to see more people experience that joy.
Please reach @hideki on Twitter, or firstname.lastname@example.org if you have any questions about the files to submit. Due to resource constraints, please do not forward me basic questions like how to model.
As far as my time allows, I would be happy to offer linguistic assistance in submitting your models. Please reach out to @hideki directly first, and do not include me in your conversation with @meguart_otayori without notifying me first. This will confuse both @meguart_otayori and myself.