I'm about to start modeling guns. But I also wish to give them an animation. So here is my question. Do I need to model the gun in different parts to make the animation? Aka the trigger, and the chamber of the gun where it release the bullet.

58 minutes ago, General Cooper said:

Do I need to model the gun in different parts to make the animation?

If during any part of the animation you can see a part it will have to be modeled.

It's normal to make these pieces on there own while modeling. Having one solid gun wouldn't only be hard to model it will consist of more polygons than needed.

During animation there is two ways you can animate the model:

1) Each part of the gun is it's own object. You then move these objects in 3D space with or without a rig. So a single gun will consist of at least 3 models if you do this.

The advantage is no skinned meshes and as a result work well with high polygon models. Animations uses very little resources this way.

The disadvantage is that you have at least 3 objects. In a game there is a limit to how many objects can be drawn and now your gun takes the place of 3 objects. Batching or Instancing (Instancing for Unreal) helps with this however it only works if there is many objects with the same material.

2) You join all your parts into one and use a rig to animate the gun vertices; this is a skinned mesh animation.

The advantage is one draw call per gun (or will be if you only use one material) and it's only one object.

The disadvantage is than skinned meshes are slow and even with a engine like Unreal that can have 64 000 triangles per mesh you don't want to use that full count, because of how skinned meshes effect vertices.

For this reason most artist stop at around 60K triangles and instead split the model into more. The result is a animation that can be a lot worse than the first kind.

A rule of thumb is: That most 3rd person games where object count is more important use the first kind. In a First person shooter use the second kind because animation quality is more important.

The smart thing to do is test both under your game conditions to find out what to use.

4 minutes ago, Scouting Ninja said:

 

6 minutes ago, Scouting Ninja said:

For this reason most artist stop at around 60K triangles and instead split the model into more. The result is a animation that can be a lot worse than the first kind.

 

 

A rule of thumb is: That most 3rd person games where object count is more important use the first kind. In a First person shooter use the second kind because animation quality is more important.

The smart thing to do is test both under your game conditions to find out what to use.

Maybe I miss read this. But why would I use the second choice for first person game. If I'm going for a clean animation?

 

1 hour ago, General Cooper said:

Maybe I miss read this. But why would I use the second choice for first person game. If I'm going for a clean animation?

Skin mesh animations are smoother and have more control.

Think of animation Blending. When a gun goes from fire to reload or to fire again, this is done by overlapping animations.

So if your gun animations was very detailed as in where the hammer moves, the safety moves, the bullet gets ejected, the ammo clip moves, the slide lock moves, the magazine catch moves, the slide moves...

A detailed gun has 8-14 moving parts. That is 8-14 objects that have animations. it gets messy real fast and hard to edit when each object is it's own. The Blending for each object has a cost and with this many you start losing performance compared to skinned meshes.

The moving parts can separate from each other if not attached to a rig.

There is also the scaling error where if your 3D tool isn't 100% scaled the parts move around when imported; A rig allows objects to scale relative to the parent.

Then there is mesh deformation. This needs skinned meshes or morph targets. The deformation allows the animator to apply better stretch and pull animation. Yes lots of first person games use this, even if it's a bit unrealistic; like how people act in movies to make things more interesting.

Last is the optimizations build into most FPS engines, like Unreal, because these engines are used to make so many FPS they optimize the skinned meshes for it.

If your gun has less than 8 parts the first way will be best. After that you will want to consider skinned meshes.

Unreal has tutorials on making guns in it's wiki you just have to scratch around to find them.

https://wiki.unrealengine.com/Weapon_Modeling_Tutorial_Shock_Rifle

6 minutes ago, Scouting Ninja said:

Skin mesh animations are smoother and have more control.

Think of animation Blending. When a gun goes from fire to reload or to fire again, this is done by overlapping animations.

So if your gun animations was very detailed as in where the hammer moves, the safety moves, the bullet gets ejected, the ammo clip moves, the slide lock moves, the magazine catch moves, the slide moves...

A detailed gun has 8-14 moving parts. That is 8-14 objects that have animations. it gets messy real fast and hard to edit when each object is it's own. The Blending for each object has a cost and with this many you start losing performance compared to skinned meshes.

The moving parts can separate from each other if not attached to a rig.

There is also the scaling error where if your 3D tool isn't 100% scaled the parts move around when imported; A rig allows objects to scale relative to the parent.

Then there is mesh deformation. This needs skinned meshes or morph targets. The deformation allows the animator to apply better stretch and pull animation. Yes lots of first person games use this, even if it's a bit unrealistic; like how people act in movies to make things more interesting.

 

Last is the optimizations build into most FPS engines, like Unreal, because these engines are used to make so many FPS they optimize the skinned meshes for it.

 

If your gun has less than 8 parts the first way will be best. After that you will want to consider skinned meshes.

Unreal has tutorials on making guns in it's wiki you just have to scratch around to find them.

https://wiki.unrealengine.com/Weapon_Modeling_Tutorial_Shock_Rifle

Oh ok I think I get what your saying. When I do get done making the model and giving it animation. Can you critique it?

3 minutes ago, General Cooper said:

Can you critique it?

You can upload when ever you want. There is a lot of people on this site that will be able to provide good critique for you.

1 minute ago, Scouting Ninja said:

You can upload when ever you want. There is a lot of people on this site that will be able to provide good critique for you.

Will do. And again thank you for your help!