How to add blood & gore to custom 3D character models?

Oblivion2500

I'm working on a game using Unreal Engine 4, Maya LT 2018, and Photoshop CC. My game lets you make your own character with different skin tones, clothing, and body size/shape. How can I add blood and gore to the game? Do I have to make new 3D models for each character model and clothing (which would make it take forever to do so)? Is there something else like some kind of vertex painting where parts of the body are blown off and the "holes" are filled with gore? What's a method of making gore for a game that allows you to make custom characters?

The type of blood and gore I want includes the following:

• Head Blown off
• Parts of torso blown off (depending on where you aim at)
• Slice in half (if using a sword)
• Head Bash (chuck of head is gone)
• Legs and arms blown off
• Body Skin damage

Games that share similar gore include Soldier of Fortune 1 & 2, Gears of War 2, Mortal Kombat X, Leaf 4 Dead 2, Killing Floor 2, Manhunt, and/or Fallout 4.

Oblivion2500

Menchen said:

If you want something fully procedural like the cutting mode in metal gear rising revengeance, it will be harder as you will need to write some fancy code similar to how booleans work in 3d modelling softwares, there might be articles somewhere on how to did that.

However, the way most games do this (at least team fortresss 2 and fallout as far as I know, and in many others), is to have the "undamaged" character model in one side, and then model each part separately (the head cut off, an arm, a hand, etc...) with their respective joints (the flesh at the cut itself). Then in your code, you simply change the models, for example, you change the torso to the headless torso, and then you spawn at the same time the beheaded-head asset in the same position the old head was.

In tf2 in particular, what they do is not to remove the "old" head, rather, they scale the "animating bone" to 0, so it looks invisible, but is still there, and then they spawn the dead head in the same position and rotation the "living" head was, plus some blood particles. So the funny thing is that they don't make the old head disappear, but rather, they make it small.

So the arms, legs, torso, and head will be separate meshes grouped together into one and rigged together, then say the character model loses its head, swap the torso model to a headless torso model. 

Since Team Fortress 2 had character models, it was probably a lot easier to make gore compared to a game that has customizable characters like Fallout which means you would have to model each part separately FOR EACH different clothing, hair, faces, and body types, etc. I thought of this idea since my game will be low-poly like 1000-1500 tris polys each character, Just use a texture for clothing, skin color, hair, and faces. It would be ideal to be able to do higher poly models like 2000-3000 polys each instead with more detail and still have a good blood and gore system.

I'm not looking for something fancy like Metal Gear Rising. To be more specific to a game that has similar gore I want would be either or both like Solider of Fortune and Left 4 Dead 2. 

poopipe

Sof and l4d do it in completely different ways iirc.

L4d used shaders to make fake holes in enemies whereas Sof simply had  the characters broken into pieces when they were built.
Both processes have been written up and published but you might struggle to find the sof stuff as it's a good 13/14 years old now (the system was called GHOUL if memory serves)

You can certainly do limb detachment with the physics/skeletal mesh setup in ue4. 

Ue4s destructible object system supports cutting as well as breaking up so if it's compatible with skeletal meshes then you can basically do whatever you want.  I've not tried it though so have no idea if it is. 

pmiller001

I imagine, if youre trying to get your own custom chunky chicken noodle gore soup goin on, you might have to model it yourself no? 

Oblivion2500

poopipe said:

Sof and l4d do it in completely different ways iirc.

L4d used shaders to make fake holes in enemies whereas Sof simply had  the characters broken into pieces when they were built.
Both processes have been written up and published but you might struggle to find the sof stuff as it's a good 13/14 years old now (the system was called GHOUL if memory serves)

You can certainly do limb detachment with the physics/skeletal mesh setup in ue4. 

Ue4s destructible object system supports cutting as well as breaking up so if it's compatible with skeletal meshes then you can basically do whatever you want.  I've not tried it though so have no idea if it is. 

I would like to go for something like Soldier of Fortune in Unreal Engine 4 since my character models are very low poly like 1000-1500 triangles polys maximum and make the gore models pieces by pieces myself in Maya LT. I just have to figure out a starting point of how to do so in Maya and UE4 together.

Obscura

https://www.youtube.com/watch?v=1zJM1gKoU14

Oblivion2500

This is basically what I'm going for, just more exaggerated with the blood and gore.
https://youtu.be/O2KK0oXOhv4