In a previous post I wrote about how I clipped a VTuber stream and whilst making the video I considered how I could make an eye-catching thumbnail. I could've gone down the orthodox path of Photoshopping a thumbnail using cutouts from the stream with some text but I got the idea to use Blender to create a 3D render since I had some beginner experience in that program. The end result is this thumbnail right here and here was the process of making it. This post assumes a basic understanding of Blender.

MMD Tools + MMD UuuNyaa Tools

.mmd is a format for models for MikuMikuDance, a program originally used to make Vocaloid animations. MMD Tools and MMD UuuNyaa Tools is a blender addon to easily import and manipulate MMD models. Hololive provides official models for a handful of members which is where I got Marine's but unfortunately an official MMD model for Subaru hasn't been released right now. However I did come across a high quality model made by the GOAT ririku3d which I respectfully borrowed for this render.

Importing the Models

Import the downloaded .pmx model by clicking import inside the MMD tab on the right side of the viewport. By default Marine's model has her coat and hat equipped which I don't want in this render. To remove this I used Mesh > Separate by Materials which splits the mesh in the top right. I deleted the meshes I don't need, then joined them back together into a singular mesh.

Posing the Models

The pose of the model is controlled by its rig or bones which can be seen by toggling the armatures under Model Setup. Once the rig is selected, change to Pose Mode from the top left. The default bones look kinda messy so I select the rig then use Viewport Display > Display as Stick for a cleaner look. Before we start posing, there're a lot of bones we don't need to move, like the ones in the hair. These can be hidden by selecting them and pressing H. Multiple bones in a hierarchy can easily be selected by pressing Shift + ] or Shift + [.

Moving bones can be done with G for movement and R for rotation. I recommend hitting either button, then using X Y Z for a more controlled movement around a certain axis. Additionally I use Local as the transformation orientation which means the XYZ manipulation is based around the joint itself, not the global axis of the workspace. If the posing becomes messed up beyond repair you can always reset by pressing alt in conjunction with G or R.

To make a pose look natural I like to do incremental changes across multiple joints. For example when posing a closed hand like in the image above I make small bends for all three finger joints. In real life it's rare for (or near impossible) to exclusively move a singular joint and any movement tends to 'propagate' across the body. For example if a character raises their right arm, their left shoulder would lower slightly.

Facial expressions can be changed in Shape Keys in Object Data Properties. Inside there will be a list of face movements with sliders.

Lighting + Rendering + Compositing

Lighting and rendering is basically where the magic happens to make a awesome looking final image. The three point lighting is a basic technique that produces good results but for this case I chose the Backlight preset provided by MMD Tools.

For rendering I chose cycles for a realistic ray-traced result. After rendering the models out with a transparent layer I then composited a white background using nodes to give the illusion of light coming in from the back.