I’m modeling a high poly character, and I know I need to retopo, but should I bake the normal map and texture before retopo? I’m guessing the retopo should bring him down to under 20,000 tri’s? Oh, and feedback on the character is welcome. He’s an old knight who’s been wandering in the wilderness for the last year or so (his shirt will be chainmail).
Hi McGillChris,
First off, fantastic model! And great to see your using Blender 3D to make such excellent work. I am also a Blender user.
So here’s my humble advice tips of the subject of a Blender to UE 4 Skeletal Mesh work flow. I’ll try first to answer your questions, then explain my own workflow for comparison.
Your initial question: “Should I bake the normal map and texture before retopo?”
Answer: The solution is simple - make a copy of the High Poly model and keep the original High Poly model. Retopologise the Copy into a Low Poly model, and yes you shouid be aiming for around 20k Tris. Now you will have a High Poly original and a Low Poly copy. Now you must UV Unwrap the Low Poly Model, before you can bake to it. Once the Low Poly model is UV Unwrapped, bake the High Poly to the Low Poly to generate your normals and your AO maps etc.
What Software are you using to Bake your Maps? I would highly recommend using XNormal - which can be downloaded and used for free. You can get XNormal here:
http://www.xnormal.net/ I do not recommend using Blender to bake your Maps as in my experience it’s baking process returns a lot of artifacts.
Also what software are you using to Retopo? Zbrush?
Okay… so a few suggestions:
You should probably not try to model the Chain Mail of the Knight’s Chain Mail shirt. The way to achieve a Chain Mail effect on a smooth surface as in the shirt in your model is to obtain a high resolution image texture of Chainmail. Take the Chainmail Image Texture and convert it into a Normal Map using either NDO2 / Quixel Suite or Nvidia’s Normal Map Conversion tool (Please ask for specific details on this one, as I don’t have them to hand.) Once you have the Chainmail Normal Map, take it and overlay it on top of the main Model Normal Map inside your chosen Image Editing Software (Photoshop or Gimp) and then erase the Chainmail Normal Map where it is not needed, leaving the areas of the Chain Shirt cover with Chainmail Normal Map. Then you can use this Normal Map to generate an Ambient Occlusion for texture painting.
Hope that makes sense and is helpful?
2nd Suggestion: If you intend the Knight to be a working computer game model. Have you considered seperating the Sword and Scabbard from main model and texturing them separately? You can then attach the Sword and Scabard to the Knight inside UE4 using the Socket Manager. The main advantage of this is allowing you to work on and texture the sword separately, saving valuable UV texture space on your main model. Also, it will mean that in the future your knight won’t be limited to just one weapon loadout - for example you can make him a Sword and Shield and attach them inside UE4.
Hope that’s helpful.
Okay, so to conclude - my own personal workflow inside Blender is that I build a complete Low Poly Model first, then I make a copy of the Low Poly and model on to it, converting into a High Poly. Then i bake my maps. Doing it this way bypasses the need to retopologise. 
Okay hope my suggestions have been useful to you. Any questions please feel free to ask. Keep up the good work!
Thanks for the encouragement. Very informative and helpful. I will def be using xnormal. This is actually my first model ever so I’ve never done any of this before. Kinda learning as I go. I’m to hardheaded to start with something easy. And I don’t have access to zbrush, but I was thinking about purchasing the retopo adding that just came out for blender. Seems like it would be pretty helpful.
Good call on the chainmail. I tried modeling it earlier with the particle system but realized that wasn’t the way to go. Thanks for the help on that, been struggling to figure out how to go about it. Would something like Crazybump work for getting the normal map from the chainmail texture? I use that for the custom textures I make in UE4. Ambient occusion is a little beyond my understanding, but I think I followed about the normal maps.
I actually already have the sword and separated, I just added it into this mesh to get a feel for how he would look with it equipped. I’ve never textured before either so I think I will start with the sword and scabbard, since it will be a little simpler than the character.
Again, thanks a ton, this is seriously helpful.
Hi McGillChris,
Glad to be of service. And hehe, I totally know how you feel about being too hard-headed to start with something easy. I’m exactly the same! I think doing something challenging is a better way to learn and improve your skills any ways! And your Knight model is great, so right on!
Unfortunately I don’t know much about retopologisng. I understand that Zbrush has a retopology tool that allows you to convert High Poly Models to Low Poly Ones in Zbrush, but I have never used it. It’s news to me that there is such a Plug In in Blender, but if there is it sounds like it could be helpful for you sure.
Yes Crazy Bump is exactly the kind of program you need for generating Normal Maps from an image texture. I see that Crazy Bump also generates Ambient Occlusion Maps. The program I use to this process is called NDO2 by Quixel - but that requires Adobe Photoshop.
An Ambient Occlusion Map is pretty simple really. In the same way that a Normal Map allows the game engine / renderer to “Pretend” that an object has depth and “Grain” or “Texture” an Ambient Occlusion Map is simply a black and white image showing how light is distributed across the Normal Map. (This may not be an exact explanation, I’m not actually an expert on Rendering, but this is a Layman’s explanation). So to make an AO (Ambient Occlusion) Map the computer flashes light onto the Normal Map - like the flash of a camera, except less intense, hence the word “Ambient” - and then takes a picture of how the shadows are cast across the Normals. That’s Ambient Occlusion.
Ambient Occlusion is, useful for two reasons. In UE4 it gives the Material information about what parts of the object should be dark and light. But it’s second use in my experience is as a base texture to use as a basis for Texture painting. So you can take the AO Map, make a copy of it, and then paint on the copy, turning into a Diffuse or “Base Colour Texture”. To paint a Texture you will need a program such as Adobe Photoshop or Gimp. Gimp is free, Photoshop is not.
On the subject of Chainmail, great example’s of 3D models of medieval armour can be found in the game Mount and Blade: Warband. And I just so happen to have a couple of those textures here to give you an idea what I’m talking about:
Mail and Plate:
Diffuse Map
Normal Map
Specular Map
Here’s what the armour looks like in game:
Here’s another example of Chainmail from Mount and Blade: Warband.
Okay, hope that’s all helpful dude. Best of luck with your Knight model!
xNormal also has output for Ambient Occlusion, curvature, etc…, 
Excellent. I’ll have to check that out.
Good point. Sanvean is correct - Xnormal can also generate Ambient Occlusion Maps, which is very useful.
But Xnormal only generates Maps from geometry, in the case of making a Chainmail Normal Map McGillChris will need to convert and image into Normals. Hence Crazybump or NDO2.
Question dos: how do I do a custom UV texture in blender? Say if I wanted to do the designs on the scabbard in photoshop, and then import it to UE4?
If you want to use it in a game, you have to retopo, 1.400.000 Tris is a bit high, before export.
yup no worries, will def be retop-ing.
Custom uv map. =Unwrap, in the UV menue “export” uv-layout. Open in photoshop.
But have you tried blender paint? Live paint on model could be fun.
When you have such a “complicated model” you need to adjust and pin some parts of the uvmap, to get an easy to paint surface in PS.
Not to make dazillions of scattered parts.
When you paint inside Blender it has not to be perfect to get good results.
So if I want to make an intricate design, I understand how to add it to blender, but how do I add it to ue4 instead of a tiling texture.
Bake your maps directly in. I’d do shadeless for the albedo map, and then you can generate the respective maps by just switching the respective textures for the diffuse. Should be in the render settings.
Unfortunately I only understand a bit of that. How do I bake my normals directly in? And what is the albedo map? And swithing the diffuse in UE4 material blueprint? Sorry, still figuring all of this out.