Training Course: Low Poly Game Asset Creation – Fire Hydrant in Blender and Unity 3D
Create Low Poly, Game Ready Assets in Blender and Unity 3D!
Through this Blender and Unity tutorial you will learn how to create low poly assets for games. Over the course of this tutorial you will learn the high poly and low poly modeling techniques needed to create the fire hydrant subject matter. You will learn how to unwrap the UVs of the final low poly model and how to bake out normal maps, ambient occlusion and texture maps.
Note: it came to our attention that some serious mistakes were made in the normal map baking tutorial, video #6. Due to this we’ve added an addendum video that goes over each of the errors and shows how they were fixed for much higher quality, and more accurate normal maps.
After the UVs are unwrapped and the baking is done we’ll take you into Photoshop to show you how to finalize the textures by adding the ambient occlusion and extra detail. Once the texturing is done we’ll go back to Blender and export the finished model out to an Autodesk FBX file and import it into Unity. In Unity we will then show you how to setup all the materials and textures and create a prefab for easy use in-game.
What You’ll Learn in this Course:
- High poly modeling methods with minimal effort
- How to create the low poly model quickly
- Techniques for creating convincing low poly models with good silhouettes
- UV Unwrapping and how to optimize your UV space
- Normal map baking and how to deal with common problems
- Baking ambient occlusion and color passes for easy texturing
- Creating detailed texture maps in Photoshop
- Making a specular map for good highlights
- Mixing and improving normal maps with Crazy bump
- Exporting the model out to Unity and setting up a prefab
Software Used:
- Blender 2.6+
- Photoshop CS 6
- Unity 3.5
- Crazybump
High Poly Modeling - part 02
Download HD Video
(24:55)
Low Poly Modeling
Download HD Video
(20:04)
UV Unwrapping
Download HD Video
(21:32)
Normal Map Baking
Download HD Video
(26:48)
Texture Map and Ambient Occlusion Baking
Download HD Video
(10:41)
Diffuse Texture
Download HD Video
(32:35)
Specular Texture
Download HD Video
(10:24)
Mixing Normal Maps in Crazy Bump
Download HD Video
(08:49)
Exporting to Unity 3D
Download HD Video
(29:18)
Normal Map Correction - Addendum
Download HD Video
(22:56)
I unwrapped my (automobile) model. Everything looks good except that I have large squares overlaying the whole 2048 UV map. I can move the squares out scale them down and leave them on the side, leaving my unwrapped model clear. Where are these large squares from?
These large squares are likely other parts of the UVs that haven’t been unwrapped. Most likely this means you merely missed unwrapping a couple of pieces. I would go back and make sure you have everything unwrapped.
Ty for the quick response Jonathan. Much appreciated.
Hi Jonathan, I notice that you are able to see the number of tris used.
Is this unique to the version of blender that you use v2.63.13, I must say i very much like the style of the interface.
If possible could you provide the details of how to get this build.
Thank you
It’s on blender.org. I downloaded the same version. He’s using the Zbrush Theme, which I find confusing. I’m using the Toxic theme because it’s easier to see what is selected and not selected.
FYI it’s listed as 2.64.
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64
Thanks chris, do i need to un-instail my old version ?
I am very new to modeling and appricate your help.
When it comes to blender i am a NEWBEE!!
HERE is my first ever model from concept to 3d model: http://cgcookie.com/blender/images/stargate-update-daz-studio-render/
My biggest issue is with noraml mapping of this model to make it more friendly for unity,I have this model imported into unity.
But thats another subject, sorry.
I have had issues in the past with downloading from blender.org. To be honest I do not know what to do!
If you could help me i would appricate your help.
I have also started a topic on the blender forum in regard to normal mapping help.
colpolstudios
Oh does anyone know the correct axis to set for import from blender to daz ?
No. Download, extract to a new folder, and open that version. Then you can create a shortcut if you like. Then switch to the old version or new version.
Hi there,
This is an addition to Blender 2.64 beta; you can download daily development builds from here: http://builder.blender.org
Cheers!
Jonathan
Thankyou, I hope they keep this addon.
Great tutorial
– Just as a side note: the “bolt” on the top of the hydrant should not have a weld bead on it, as it is actually rotated using a spanner wrench to open the flow valve inside the hydrant itself which allows the water to flow through the hydrant. But thats just “nitpicky.”
Hello from Moscow, Russia.
It was a crazy lesson for me, but very interesting! It is sad such interesting lessons is small enough.
Thx Jonathan.
Hi, how can i select a material of polgon or vice versa in cycles in case of multi material.
Very nice tutorial, as usual
One thing I just stumbled over while using Unity and Blender.
The usage of the two different coordinate systems does matter once you use functions to move or align objects.
The only way I found to fix it is to apply a 270 degree rotation on the x axis in Blender and set the forward direction to “y-forward” during the export or parent the object to a empty.
Really great tutorial. I DO HAVE A PROBLEM (probably something simple). Every time I try to bake my normal map it is SOLID BLUE. I’ve gone back through the tutorial multiple times looking for a clue on this but can’t seem to find anything I’m doing wrong that is obvious.
Any clue much appreciated.
Further to the solid blue normal map. To test this behavior I’ve created two planes – one is complex and subdivided several times. Some of the vertices have been dragged along the z axis, etc. etc. giving the complex plane some peaks and valleys. The simple plane is subdivided once. I unwrap the simple plane. I then go to bake, select normals, tangent etc. select complex mesh then simple then ( with Selected to Active selected) hit Bake. and again – a solid blue normal map. Tried same with simple and complex ‘monkey mesh’. Same result. Have I got something ‘fubarred in Blender itself?
Hi there,
It sounds like one of two things. Either “Bake to Selected” is not enabled. Or you only have one of the meshes selected. In order to bake the high res to the low res you must first select the high res mesh, then select the low res mesh. Then you can press bake. The low res mesh just needs to be your primary selection, as indicated by the brighter orange color.
I hope that helps!
Thanks for the quick response. I DO have Bake to Selected enabled and DO have both meshes selected (Hi res first then low res). As noted above I have also tried this using a simple plane and then a more complex plane with some vertices pulled up and down to give it some ‘bumps’. Same result.Low res object is brighter orange.
Here’s what I get: http://www.alphabetem.com/slidingpuzzle/largeImages/hydrantscreen.png
Great tutorial, and the one that convinced me it was time to become a Citizen Member!
I do have a question if anyone knows… I’m using GIMP rather than Photoshop, and I couldn’t work out how to paste the specular map into the Alpha Channel of the texture. So when I import to Unity, the specular isn’t right. Just about everything else was fairly similar in GIMP to Photoshop, but I got stuck on this one.
Hello, this is a great tutorial and I’m learning a lot from it. However I have a problem with the array of bolts. The second object wants to sit right on the empty and all other objects in the array are offset from that which formed a spiral. I can’t get them to centre on the empty and arrange themselves in a circle with the object as the centre. I’ve checked the video several times but had to fudge it by moving the empty. I can’t work out why it won’t work properly. Is there something I might have done that would make the origin of the first copy sit on the empty rather than be offset the same as the very first bolt? I’ve tried applying movement and rotation but it makes no difference.
Hi Stuart,
Late reply here, since I just joined, and I ran into the same problem. Seems like you need to hit Ctrl-A with the Bolt selected, then apply the transform to Location, Rotation & Scale. Thanks to this video (http://www.youtube.com/watch?v=1dsL4ocuWd8) for explaining it. It might be a Blender 2.6 thing?
I gotta say – this is frustrating. For some reason when I bake my High poly to the Low poly I get no detail on the map – JUST BLUE. HINTS WELCOME
Hi there,
This likely means your high resolution mesh is disabled at render time. To fix this select the high resolution mesh and press CTRL+ALT+H. This will re enable it at tender time and allow you to bake the map.
I hope that helps!
Jonathan
Still BLUE.
Here’s what I get: http://www.alphabetem.com/slidingpuzzle/largeImages/hydrantscreen.png
Okay – HERE IS PART OF THE PROBLEM – which to the un-initiated doesn’t seem like it should matter.
If I select Hipoly on layer 1, then shift select low poly on layer 2 then bake I get a solid blue map.
HOWEVER
If I select layer 1, then hipoly, then ~ (tilde) THEN low poly it BAKES.
baking between layers with both objs selected on their own layer WITHOUT sitting on layer 1 and hitting ~ seems to be the problem.
very annoying.
Not sure where to post a general Blender question but here goes: where do I get more sculpt brushes? I only have one available. Thanks!
In video “High Poly Modeling – part 02″, at 17min 10sec, you create an Empty and use it as Object Offset. Each time I do this, it automatically create the bolt over my Empty and I definitely don’t have the same control as you have with the array… Any suggestion?
Array + Empty is driving me nut, I don’t know if it’s my version of Blender that is all messed up but it definitely doesn’t work as I want.
Hi Eric,
When using an empty for object offset be sure that the empty and your objects origin are at the exact same location. For this you need to offset the actual mesh (in Edit Mode) from the origin.
I hope that helps!
Lowpoly_firehydrant_02_modeling : at 11 minutes. the snap of the end of the weld to the surface of the main structure fails. Jonathan changes the length a little bit and then succeeds in the snap. Mine keeps failing and I don’t know why. Could someone please take a look here ? Who succeeded in doing this ? Help
Made a vid to show this : http://youtu.be/Q1H5qPmBNf4
You need to make sure you have enable “Snap individual elements on the surface of other objects” that’s right next to the whole snapping menu thing. From your video quality I can’t really tell if you do.
I’ve tried it without the option enabled now, after u said that, it’s cleaner now but the edge is straight. I think I won’t use that feature anymore. There is either a hidden step somewhere or it’s too buggy to use. I’ve tried different sizes, different distances, locally, globally, nothing works.
Ok I’ll take back what I’ve said lol, i just found the problem.
I guess looking for hours really helps with memorising this method !
You have to disable “Snap to Itself”, next to the “snap to the surface” in order to get this to work. Even though Jonathan didn’t disable this. (Using Blender 2.63).
Please tell me what’s going wrong here in part 6 of the video (8:05).
http://imageshack.us/a/img688/4480/errorcorrectuvs.jpg
The ‘Operator’ window is empty. When I press F6 to bring up the dialogue-box, the options are disabled. The ‘Correct UVs’ option is not available and the Operator menu remains empty.
Hi John,
This is a common issue with blender, the solution is usually to close and re-open blender. it occurs more with new features.
Does this work for you?
– Alex
I fixed it by adding a loop-cut (ctrl+R) and confirming it without moving it. Then do a Ctrl+E to edge-slide and confirming it. Then and only then, I was able to do F6 and bring up the menu to toggle-on “Correct-UV’s”.
Sorry if it’s just me talking here but I fall from one pit into the next. Now I’ve fixed the normal map as best as I could but the edge is still ‘wavey’ and I’m trying to understand why.
http://imageshack.us/a/img706/9131/waveyerror2.jpg
http://imageshack.us/a/img820/2882/waveyerror.jpg
http://imageshack.us/a/img405/4671/waveyerror3.jpg
Is the size of the low-poly wrong compared to the high-poly ?
How many objects in a game are typically high poly models retopologized to low poly, and how many are usually just built low poly?
It varies with every game. However generally all the key assets, such as characters, vehicles, and any other object that is important to the game and viewed up close will generally be higher resolution. Depending on your target hardware you may normal map the majority of the objects, or only a few. It all depends on the end result your shooting for and the specifications for the target hardware.
I think I asked this somewhere else but,
Why not just use your base mesh for your low poly when doing a character or vehicle? It looks like you retopologize them instead.
The basemesh is generally not optimized for animation and such, it’s much more uniform to provide even, clean sculpting geometry. The retopology is done to provide a model that is optimized for animation and deformation with clean topology that’ll be far more flexible.
This is not always the case, but generally is.
-Jonathan
That is a most excellent response Jonathan! That makes a lot more sense to me now. Thanks!
I very much enjoyed this tutorial thanks Jonathan.
Could you point out a texture painting tutorial for me please as I wish to fix the seams.
colpolstudios
Hi guys,
first i would like to say thanks a lot for the great tutorials!
I am kinda stuck with the Normal map baking.
Somhow my normalmap has wire artifacts in it which i dont know where they come from.
http://desmond.imageshack.us/Himg29/scaled.php?server=29&filename=screenshot20120927at508.png&res=landing
I already tried with and without subsurface and with and without flat/smooth shading.
I have no clue where the black lines are coming from.
Almost looks like Triangles.
Anyone have some hints for a beginner?
Thx a lot in advance!
think i figured it out
Took me some time but i forgot to check Normals in the Image Sampling Section.
Doesnt look perfect yet but much better.
Really enjoying this tutorial! But I’m having a rough time with the normal maps. First of all I can’t get Blender to render the lighting in real time to see if the normals are working. When I hit alt+z it does not become a silhouette but just makes the normal map brighten slightly (in the 3d display).
Also, when I tried to add some edge loops so I could bake with the sub-surf modifier on, it ruined my uv map even though I clicked the “correct uvs” box in the edge slide options that come up. The main body section of the uv’s became separated into multiple pieces instead of one. You mentioned that there’s another way to do this if that doesn’t work. Is there another tutorial that covers that?
Other than that, great tutorial man! I want to finish it very badly, I just need to get over this hump. You’re the best tutorialist on the interwebs imo… and I’ve watched a lot of them. Too many people just don’t know how to be concise about their thought process, but you’ve got that down to an art nearly as much as your skill as a modeler. Thanks John!
Also, fyi, I’m using Blender 2.63. So I suppose the problems I’m having might be due to the difference in builds. Could there be some default settings that have changed also? I’m really stumped here… I’ve been through video #6 nearly a dozen times to double check everything, and I’ve followed your directions as thoroughly as possible.
In the final video at 25:15, you mention that a texture seam can be removed by cloning it out in Blender. Can you go into more detail on how this is done. Thanks.
http://blenderart3d.blogspot.fr/
If I wanted to upload my low poly model with textures to a website like blendswap.com, or sell the asset to a game developer how would I go about that?
Assuming they are using Unity also, can I export the packed model out of Unity or do they have to just apply the textures themselves?
Ok, i really need Help. I try fix this for like 2 days.
I try to Bake Ambient Occlusion from floor tiles i was doing bake’s before on more complicated objects but now my 150 face object bake like forever and fan inside my PC spin like crazy.
After few min of bake i just give up, bar was on half way. I started on 2k map , but after lowered to 1k and even to 0.5k and still damn slow… even samples i reduced from 16 to like 6
I have no idea whats wrong i never had this problem. On your vid bake more complicated object take few sec ( or speed up’ed?
)
My spec:
MSI Laptop
CPU: Intel Core i7-2670QM
GPU: Nvidia GTX570m 1,5GB GDDR5
RAM: DDR3 8GB
HDD: 2x 500GB in Raid 7200RPM
Im 100% sure i have something wrong with settings but can’t find what. I gona try get back to Default Blender settings.
AO bake can take anywhere up to 10 minutes depending on resolution and scale of your scene and max distance.
After back to Default Blender settings seems like problem gone. But will check lower Resolution & Max distance couse still its slow
Thanks for tips , didnt check that value before
Cool looking tutorial. Haven’t tried it yet though. I know this is geared towards Unity but really this type of tutorial should be learned and be done by 3D artists in general. Even if you can’t model great it’s still valuable knowledge knowing how this all works. Also you can just model this stuff low poly and use good looking textures to make it more interesting. While I don’t play video games on my Xbox 360 all the time I am playing Deus Ex Human Revolution right now so this tutorial caught my eye. From the famous saying by Jonathan Williamson “Very cool”.
When you’re adding and removing the loops to refine the normal map, is it possible to duplicate the lowest-poly model, the refine the map by adding loops to the first mesh and apply the final normal map to the previous low-poly version, the mesh without all the loops?
Look at the last video number 12. If you triangulate the object you don’t need to add extra geometry.
The array modifier is not working for we when i set the object to empty it just duplicates the bolt to the center of the origin, i don’t understand why?
Hi Louis,
Can I see a screenshot of your array modifier and object setup? It’s likely the object scale is not 1,1,1 or the object origin is offset.
Sorry I’m really new to Blender I’m just trying to figure out how it works i still don’t have a good enough workflow yet so i know i have missed something. http://imageshack.us/a/img145/8617/firehydrant06blend.png
http://linuxers.org/article/adobes-content-aware-fill-huh-gimp-already-had-it-years
http://chathuraw.wordpress.com/2010/03/29/photoshop-cs5-content-aware-fill-vs-gimp-resynthesizer/
For those who don’t know that GIMP have a similar tool that Jonathan used with Photoshop.
Hello. I keep having the problem of realtime rendering. When I switch to textured mode the model does not go black without a light source and no normals or spec or anything like that actually shows up. It’s just like in standard 3D viewport. I have done and double-checked everything and my settings for the stuff from the tutorial are exactly how they should be. This must be something else. What is it?
What is your “Shading” mode set to in the Viewport Properties panel? It should be GLSL, and you also need to have the render engine set to Blender Internal. If it’s set to Cycles GLSL won’t be available.
Everything is set to the exact same as in video. Meaning GLSL, Blender, Texture Solid and so on.
Here is some extra info:
When I change colour in the Material options under diffuse the colour does change in the viewport, but it doesn’t pick up any information from the textures panel.
try removing the material and adding a new one, this can happen sometimes, also make sure you do not have nodes checked.
-Alex
Hi,
Really looking forward to this tutorial. However I cannot seem to download the source files, get access denied error in the browser?
Thanks for the heads up, I’m looking into it right now.
Cheers,
Jonathan
Okay the download should be working now. The file had been accidentally removed during a cleanup or server move. Thanks for the extra set of eyes!
Cheers,
Jonathan
Thanks for the fix Jonathan, this is a really helpful tutorial.
Cheers,
Tim
Hi I have been working on your tutorial and I cannot seem to activate UV Correction on the Loop Edge Cut tool. Is there another way to do the normal mapping without using the edge loops with UV correction.
Make sure you have a recent version of blender, and yes you can, you just line them up manually.
-ALex
Got the same problem and came here googling for a solution
In Blender 2.65a that checkbox just doesn’t receive a check mark when I click it.
Great tutorial. I followed it exactly except I used Quixel nDo2 instead of Crazybump for the texture normal mapping and mixing. Worked quite well. Here’s my hydrant. http://cgcookie.com/unity/images/fire-hydrant/ Thanks Johnathan!
So in the addendum, how did you get model the three spigots to become a single piece with the vertical column? I can’t figure out how to do it cleanly.
Great series, citizenship is totally worth it.
You need to create some extra loops so you have an 8 point cylinder connecting to 4 faces on the perpendicular cylinder.
-Alex
Hi, Thanks for the very informative series, I learned a lot.
I hit one issue though, which I just can’t figure out. Unity refuses to apply the specular map in the alpha of my diffuse PSD file unless I invert it. (I.e. It’s now mostly white instead of mostly black). If I apply the tutorial’s texture to my material/model, the specular map is applied correctly, so it’s definitely something to do with the PSD file. (The two psd’s alpha channels look pretty much the same in photoshop)
The only difference I could spot is in Unity on the texture preview. If you switch to the alpha, the tutorial’s alpha appears as pure white, whereas mine appears as dark greyscale (same as in photoshop).
Please have a look at this image, which illustrates the problem: http://www.retrotoast.com/downloads/LowPolyAssetCreation-UnitySpecularIssue.jpg
I’ve also uploaded samples of the custom diffuse PSD.
Specular Applied: http://www.retrotoast.com/downloads/hydrant_diffuse_specular_applied.psd
Specular Not Applied: http://www.retrotoast.com/downloads/hydrant_diffuse_specular_not_applied.psd
I would recommend using targas instead of psds, anywho you need to up the levels to make it work.
in photoshop press ctrl+L to go to levels and then crank that contrast way up, remember you can always tone it back in unity.
-Alex
Thanks for the reply Alex. I’ll do some experimenting with contrast to see how it affects things.
However, that still doesn’t answer my question. Check this image: http://www.retrotoast.com/downloads/LowPolyAssetCreation-TutorialVsCustomAlpha.jpg
My alpha channel is dim like that because that’s what was in the tutorial. I don’t understand how the two can have such different results in Unity. Both of those maps work fine in Blender.
Hmmm, I actually haven’t followed the tutorial, but levels will help you, could be a difference in material settings.
-Alex
I’ve been watching the Blender intro and now the low poly training. Many thanks for informative videos! There is one important issue I cannot quite put into place what comes to the modelling workflow:
Low poly training uses the workflow ‘high poly – low poly – unwrap, bake and texture’. It seems very logical and one gets to see the ‘clay version’ of the final model quite early on before going to optimization steps.
However, how does this approach suit to modelling objects which are built of repeating the basic blocks over and over (say, many buildings or certain kind of spaceships)? My initial thinking is to
1) model the blocks
2) UV unwrap, normal map and diffuse map them (into a smaller texture)
3) build the model by copying the blocks and adding other details
4) bake AO with another set of UV coordinates into a larger texture
However, this does not sound too elegant and kind of breaks the workflow (needs to go back and forth between modelling and texturing (1-2) before getting to put together the real thing (3)). Is there a clean way to model the high poly version in situations like this? Something like linking together all instances of the blocks (which may be all over the place, not just as an array) and texture the master blocks only after the high poly step is complete and get the UV coordinates copied everywhere?
For something like spaceships my personal workflow would be:
1. create modules
2. create low poly versions of modules
3. assemble high poly modules into spaceship
4. replace high poly modules with low poly
5. retopologize from there
6. repeat for rest of ships
-Alex
Great tutorial! I’m still new to blender but have no trouble following most of this series. Must be the great teaching :p
One problem I’m running into: during video 6 (normal map baking) at 23:25, in reference to deleting the “extra” extra loops, JW says: “If the UVs get messed up you will see major distortion.” Well, that’s my problem. Every time I delete/dissolve these extra edge loops on the low poly model (after baking the normal map and adding it as a texture), it distorts my UVs. When I added these edge loops, I did check the “correct UVs” box, which I thought was supposed to correct this problem.
Can anyone give me insight into this problem? What causes this? How it is corrected?
Image of distortion: http://i1358.photobucket.com/albums/q764/blenderitme5/Deletingextraedgeloops–distortedUVs_zpsaa25fa3f.png
My blend file: http://www.mediafire.com/download.php?3ideu64umymilq6
Hi there,
I actually recommend you skip ahead to the addendum for this part. The way I originally did this section was incorrect and causes problems, so I corrected them in the addendum. It should help shed light on it for you.
Thanks for the reply. The addendum really did clear it up.
Now every time I am playing a game and I run past a fire hydrant I am going to stop and go back to look at it and say “Hey theres no chains on this fire hydrant” haha.
Great series so far Jonathan.
Really great series. Glad I found this site.
Greetings Gentlemen! I’m working on a little project of mine and have run into a normals conundrum. For some reason when I bake out the normals half are perfect, and half come out a pale green, with either no detail, or really wonky detail that doesn’t even exist on the high poly model, any ideas?
Well finally finished watching the series. Learned a lot. Thanks Jonathan.
You’re very welcome
This tutorial was the reason I upgraded to citizen membership and it was totally worth it!
Welcome to Citizen!