How to pose your skin - jessicanataliagta/mutare GitHub Wiki

First of all, you need to pose and adjust the scale of the new model to fit the size and position from the original game model that you want to replace.

To pose your character, it will be necessary that the character already have a skin rig, so you can move the bones to match the positions of the model that you want to replace. If your model do not have a skin rig, you can make a temporary rig on mixamo just for adjust pose and scale. Keep in mind that you need to do a new auto rig after adjusting the pose and scale, because rigs usually breaks when position and scale is changed.

Usually, the model that you are going to convert probably will already have a skin rig

In this exemple I will pose my model to fit a character from GTA Vice City

Open your new character model on 3DS Max

Open the character from the game that you want to replace, the scene will be like this. In most cases, the scales, position and characters pose will be different, we need to adjust that.

Open the Scene explorer:

Select the original model from the game, and click on the "eye" icon on the scene explorer in order to hide it.

Select the skeleton (not the model) of the new character.

What is wrong in this case? the rotation, the scale, and the pose. So let's fix that.
To fix the rotation give a right mouse click, then click on the square window on the Rotate option.

This open a window where I was able to fix the rotation by putting 90,0 on X. Keep in mind that while rotating you should allways use 360 degree rotation entire numbers like 90, 180 to make a full rotation, otherwise the character rotation will have a small inclination.

To fix the scale it's better to unhide the original character 3D model, then with the skeleton of the new character still select, click right mouse click and select the square window.

On Offset:World, put a number to increase the size. By default is 100,0 so I will increase. But if my new model was bigger than the original game model, then I would need to do the inverse, decrease this number.

In this case I replaced 100,0 to 1000,0 and then the scale looks fine. And usually works like this, with fixed numbers. 100,0 to 1000,0 or 5000,0 or 10000,0 would fix to the right scale. (and 100,0 to 50,0 or 10,0 to decrease).

As you see on the image above, the model position is different, so let's fix it. With right mouse click, click on the square window on Move.

Clicking with the arrows, tweak the position on X Y Z.

Now with the position and scale fixed, we need to fix the pose.

You will need to keep hiding and unhiding both characters models in order to see the bones.

Go around rotating the bones until your new model matchs the position of your game model. When rotating the bones, is usually good to use the rotate box and keep the same value of rotation on both sides, this will keep the symmetry of the model intact. On this case I used Y -35,0 on the right and Y 35,0 on the left.

Now my new model matches properly the rotation, position and pose of the original game model that I want to replace.

To finish it, delete the original game model and skeleton (by selecting both of them on the scene explorer and hit delete button on keyboard).
Then click on your new model, go the the modifier list, click right button mouse on the Skin modifier and select Collapse All.

Select Yes.

Select and delete the original bone of your skin. Then select "Reet Xform", "Reset Selected"

And give a collpse all to the xform modifier.

Now we have a model properly adapted to be used on auto rig.