Material Colour or UV? Have to UV?

Hi All,

Noob question on Blender which I am sure is a simple quick question which is confusing me.

In Blender, there is a Materials Tab, which you can then colour your model, However when I watch tutorials or anything related to Blender texturing/adding colour, most if not all talk about how they add a Colour Pallete and then simply UV map their model and chose the colour on that mesh…So the question is, why does Blender have a Material tab for Colours where you can with a click of the button chose a colour and then edit the nodes to your liking, if you shouldn’t really use them and using UV Mapping, with Colour Palattes? Hope that question makes sense.

I know about UV mapping and done this in the past along with colour palletes from online to use on models, however still new to Blender and just wondering if the materials tab base colours that are provided are there for previewing the look before you go and UV Map?

My models are going to be more straight one colours per surface (ie Skin one colour, Clothes another colour, etc etc.

I am aware that UV Mapping is basically a Must in the gaming industry to map all colours/texturing onto one UV Map texture, then you can duplicate as a Normal/Bump/Spec etc. Just checking on why it is there in Blender if basically shouldn’t be using it for final?

Material Tab example with colours you can chose on model:

UV Map Colouring Example found online as an example:

Games are realtime.
In order to facilitate their display, creator have to try to minimize data load.

When you create a palette as one texture map, UVs are unique data per mesh.
But same material can be applied to all meshes.
If you don’t use that, it means that you are creating one material per mesh.

It is also possible in Blender to have one material for all objects and use object color or object index or have a random color.
You are not forced to use a texture.

You are free to do what you want. You are free to prefer ease of use to data size optimisation.
For games, way to optimise data load will depend on game engine used.
Nowadays, many game engines can handle one color property per object.
It is not obvious that UVs+Texture will be the most efficient way to optimise data load.
That depends on engine used.

But if your assets are not supposed to be used outside of Blender, just do what is the most effective for you.
That does not really make sense to lost time to transform UVs of dozen of objects, when defining an object color per object is a lot faster.

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Hi @zeauro

So my game character is going to be a colour model not texture unless I have to I guess, for example colour on each part (hair, skin, clothes, items etc etc).

An example from Google on what someone has created shows an example of what I mean…

So people tend to use the colour materials to put in the colour shading, edit the nodes and then as it stays in Blender to Render for a picture, then that is completely fine and I get it.

However as my character is going into another Engine (UE5 probably) I have already exported to the engine to test and works just to check. However I assume I have to UV Map. I understand UV mapping and I get the Baking of normals, bump, spec etc, however I was wondering if I have to UV Map. Not trying to find away Not to do it, however just didn’t know the reason for the Material tab in blender, if people then UV Map and then have to put other colours/palattes on it. I hope this makes sense. So assuming that I am going to have to UV map my character and put the colour textures on it? I am going to have multiple NPCs in the game with same process of one colour per part/section so wanted to see what the Best practice thing to do is.

Below was found on Google Images as an example to what I mean.

For realtime rendering You want to have as low materials per static scene/dynamic objects as feasible

Even UE5’s nanite performance is constrained by number of materials. (number of pixels*number of materials on scene to be precise)

Example from “Polygon City”:


Whole character have single material, some areas have texture, but mayority of flat faces are just UV unwraped to single color palette.

While doing Your model You prepare pallete, and then unwrap model, scale UV to albost 0, and then move those uv to correct colors on palette:
|257px;x135px;


Or You can apparently use this addon that just BA just showed me as AD right now :smiley:

Paletter - Blender add-on for baking materials colors to image palette.

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Amazing @gorion103

My question was why is there the colours in materials to use, if everyone is basically UV mapping the colours on to it and it makes sense to due to being live and baking it as one is best.

The Addon looks great so going to use that!

I’ve tried the UV scale 0 and scroll to colours in past which was good but want higher colour Res, blend of a colour like the material colours and this Addon you shared looks really promising so thank you!

Your question

does not make sense because you need it to be able to give your material a colour whichever method you use.

Even if you use the colour pallet method you are still using the colour input of the material. You have to plug the pallet map into it! The colour input is a necessary for any texturing method.

Not everyone one is using the colour pallet method, It is not that common most people UV unwrap and make complex colour, roughness, metallic and normals maps for export.
Others make materials that are totally procedural (which is great inside Blender but you have to bake the results if you want to export).

Not every one is UV unwrapping.

Inside blender you can also use generated, object, normal, camera, window or reflection texture coordinates for mapping textures.

You can also assign different materials to each face you want to be a different colour without any mapping at all.
For each material you can use the colour input to change the colour and also each material can have its own roughness metallic value etc. etc.

There are many texturing methods but they ALL use the colour input.

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Adding to what’s already been said here - If you’re only ever going to use your models within Blender itself (i.e. Just rendering, and not exporting elsewhere such as a game engine or whatever), and have no need for anything more complex than single color materials, then just selecting a color in the material panel is perfectly fine.

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Yes, and you can export it as well! Most export formats will export the correct colour and roughness values as simple numeric values obj, fbx etc.

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Thanks @DNorman @Magnavis.

I’m using blender for my models and exporting to at the moment UE5.

I am basically checking as I can use the material colour input on the model with clicks of buttons if I can simply export but actually best practice would be still to UV Map the models and use colour palettes and then export the models.

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Yes, standard practice for exporting models to game engines is to UV unwrap and use maps for Diffuse, Roughness Metallic and Normals. This is the “pbr metalness” workflow.

I just wanted to clear your confusion as to why Blender materials have a colour input in which you can set a simple colour.

The key is you need that input, that it is where you have to plug in your Difuse map (or alebo/base colour which are different names for the same thing). Your colour pallet image is a diffuse map.

Your game engine will have a similar input that works in the same way, you can either assign it a “map” or give it a “solid” colour value.

This would be the equivalent to setting a simple colour in Blenders principled shader’s colour box in UE5

base-color

In Blender for simple solid colours you can just set a colour and it will export as a numerical RGB value. This does mean that you need separate materials for each colour.
Blender will export them as separate materials assigned to specific faces (the ones you assigned each material to). I am confident that UE5 will set up the materials with a colour input node for you when you import the materials.
But yes you are right, it is good practice to unwrap and use maps for anything that is more complex than one single colour.

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