Is a high poly Model Needed for Realistic PBR Game Assets?
polycounter lvl 6
Hello,
I would like to know if a high poly model is necessary when creating a realistic game asset, especially in the game industry. I ask this because high poly modeling can be very time consuming and I haven't had much success with normal map baking thus far for complex models where xnormal doesn't get small details like screws and bolts and even most indentations, and without the high poly model is a normal map still needed for details that are not in the low poly model and if not ,how would you model the low poly, would i bevel edges to have better results like in this example I did. This particular model has 6319 tris and 3293 verts.
And would the normal map be as simple as this :
or would the normal map be more detailed? The end goal is to be able to sell my models like unity asset store and ue4 marketplace and here is another example model which is 8k tris, can this be textured the same as the first model posted? The software I used for texturing is DDO and NDO using a custom made ID map in Photoshop. And these are only two of many more models I have.
One more thing how would i go about modeling something where i can't find enough reference images for details or don't know the name of parts which would make finding more reference images difficult?
I would like to know if a high poly model is necessary when creating a realistic game asset, especially in the game industry. I ask this because high poly modeling can be very time consuming and I haven't had much success with normal map baking thus far for complex models where xnormal doesn't get small details like screws and bolts and even most indentations, and without the high poly model is a normal map still needed for details that are not in the low poly model and if not ,how would you model the low poly, would i bevel edges to have better results like in this example I did. This particular model has 6319 tris and 3293 verts.
And would the normal map be as simple as this :
or would the normal map be more detailed? The end goal is to be able to sell my models like unity asset store and ue4 marketplace and here is another example model which is 8k tris, can this be textured the same as the first model posted? The software I used for texturing is DDO and NDO using a custom made ID map in Photoshop. And these are only two of many more models I have.
One more thing how would i go about modeling something where i can't find enough reference images for details or don't know the name of parts which would make finding more reference images difficult?
Replies
Also, with tools like NDO and the Substance tools normal/height detail can be done at the texturing phase. You can bake your maps for the ddo/substance workflow based on the geo so a NM isn't required. You can also paint your normal detail and use that normal map as a basis to bake other maps.
Just make sure your model is cleanly triangulated before final export and that there are no surface normal shading errors.
Study examples, there are many available from many games by various artists. I think you will quickly figure out the answer to your question from there.
https://www.artstation.com/artist/lonewolf3d
http://www.bergman3d.com/
https://www.artstation.com/artist/ethanhiley
https://www.artstation.com/artist/pirat
https://www.artstation.com/artist/lildragn
Now as far as marketplace assets are concerned it's kind of up to you to decide on the style and the execution technique. There might be room for assets with less accurate details than the ones shown in the above links (TF2 style for instance) ... but if you do want to create assets with higher fidelity then yes, you will need baking.
As for things you don't have enough refs for....be an artist, improvise, use your imagination.
but the baked normal map would come out like this even with exploding the mesh
where a lot of detail is missing and this was bake in xnormal and maya which gave me similar results this normal map has been tampered and the original this has to layers to sharpen the image smudged normals i did to get rid of a lot of errors.
Caveats include but are not limited to:
1. Must use custom normals. Maya does this by default now to an ok degree. We have custom tools for workflow purposes.
2. Must eat the cost of using extra Verts/Tris. In some cases it may triple your tri count. Be smart about it, and it is ok.
3. Must change the mindset of an ingrained / indoctrinated workflow.
4. Advanced material blending in engine is a huge plus.
5. Must eat the cost of advanced material blending.
6. Deferred Decals will greatly improve the workflow.
7. May have to use a second UV channel.
8. Must eat the cost of a second UV channel.
9. Must understand that sometimes, you just need to make a high poly and bake.
I have created similar high quality assets without a high poly step, and with proper iteration and tools, can pump out assets that look baked in far less time. Once consoles/PC's have a baseline similar to MS Project Scorpio, high polys will be rarely necessary.
Learning to do the workflow is great as musashidan said, but it would also be smart to prepare for the future.
If your game has a significant triangle margin for viewmodels then you may not need a highpoly. Smooth edges can be approximated with support loops. Some engines even support realtime subdivision, which reduces the need for baking because the game model itself can be a highpoly model.
But, in practice, to achieve best results in a realistic budget, you need to bake from a highpoly model. Triangles are still limited, so normal maps still have utility. Certain workflows can help you automate highpolies more.
If you're not doing viewmodel assets but more environment stuff, you might want to look into texture atlasing.
In order to remove the high poly step, you have to stop using Zbrush. We all know that Zbrush is THE essential tool in a character pipeline, so how do we remove it? How do we tell character artists that they have to go back to manually making a character using Sub-D modelling? There may be a solution, but I don't think any current character artist will be able to ditch Zbrush, so we are just biting the bullet and eating the cost of making the character models all twice.
Ideally your characters will just be 70k+ triangles and you can just model all the details you need for many characters, but most artists would still use zbrush and that defeats the purpose of streamlining this step.
Firstly i believe using custom normals as a means of faking soft edges etc. Is a false economy in most asset related cases. The method is expensive, destructive and does not LOD effectively - It works well for objects that use tiling textures and dont LOD but as a replacement for baking on a character or environmental prop the negatives far outweigh any (dubious) gain in productivity for me.
A middle of the road approach where larger scale information (edge bevels etc.) is baked and higher frequency/non-sillhouette details are added using textures seems to yield the best results in terms of flexibility and speed.
Eg.
Your high res models are quicker to build/sculpt, simpler to bake and you can rework large scale information without destroying time consuming details.
Your low res models can be cheaper and LOD effectively.
Final decisions on surface information can be deferred till far later in a project ( a godsend if your renderer isn't finished yet).
So yes, in summary I think you do need a high res mesh, it just doesn't have to feature every wrinkle or screwhead