Interesting normal map technique

Interesting technique! My computer cant handle Blender in sculpt mode for any useful amount of polygons so this technique looks like it'll be useful for one of my projects.

It looks especially useful for making stylised normal maps which is perfect for what I want to do.

Unearthly challenge Day 3&4

Update: I refined the connection between engine and hull sections as well as added various other details.

5 simple steps to making a clean cut in Blender

In this post I will outline the method I use to making smooth cuts (or spaces) in my meshes. It's pretty basic and I'm sure you'll find examples of this elsewhere.

While I admit its not completely perfect because of the introduction of ngons and triangles, the result seems to be quite good and the amount of polygons required is quite low which is great.

The following images show what I'm talking about. The second image uses the same method to achieve the opposite shape.

The following steps assume you have a mesh with a Subsurf modifier.

Step 1 Position where you want the cut/space in your mesh to be.
I usually use the Edge loop tool (ctrl+R) to set where I want the loops to define where the sides the thole will be. It helps reduce unwanted distortions. If your mesh happens to have edge loops already there, use those.

Step 2 Make some lines 
Draw an edge using the Knife tool (K) around the area that you want to become a hole. Ensure that when you change direction you leave a triangle between the edges as shown in the picture. Make sure the edge you are drawing is close to the existing edges you defined earlier.

Step 2 Make some space
Delete the polygons where you want the space to be. Notice how the mesh is being smoothed. This will be fixed later.

Step 3 Extrude
Select the edges around the polygons you just deleted and extrude downwards (or whatever direction you want). Again, notice how the mesh is smoothed. The next step will resolve that.

Step 4 Add lines
Creating these lines will make the corners sharp. Use the Knife tool and cut from the outer edge of the mesh up to the corresponding vertex of the triangle mentioned in step 3 making sure to cut as close to the corner as possible.

Step 5 Add sharpening line
The purpose of this line is to make the edge sharper as well as producing smoother geometry where the triangles are.

Done. I hope someone found this useful.

Unearthly challenge: Day 1 & 2

Well, I just got sucked in to a challenge. Game Artisan are hosting the Unearthly challenge. Me having a bit of spare time and being a long time lurker of the 3DTotal forums I decided to join.

Out of the four categories I went for the 3D vehicle as I already had an idea I was pretty interested in trying out.

The Bullfrog

"The Bullfrog is an Oceanic planetary explorer. With its powerful hybrid engines it can cross vast oceans either above or below the waters.

It can be dropped from orbit and land using parachutes. Once on the water its hydrofoils deploy and off it goes.

Massive waves? No problem, using its small wings to provide lift, it can hop over them and its computers can even map a route allowing it to jump from wave crest to wave crest resulting in more efficient travelling during planet wide storms.

If needed it can dive up to 100 metres under the surface and provide life support for a crew of 3 for up 24 hours."


During the first day I quickly blocked it up and added a subdivision modifier because I wanted some nice smooth curves.

Day 2: Added more detail and finalised main sections of the model.

At this stage I am almost satisfied with it. I'm still working on defining certain areas.

Comments are welcome!

Lester Animation Project

I'm currently playing around with my rat character with the goal of making a short animation with it.

This is just a WIP shot from the viewport. I will post something more interesting soon. I am experimenting with different looks for the final look of the animation. To do this I will be doing some renders of various poses of the character along with props.

Soon I will also post some (bad) story board of various shot ideas along with some plot stuff.

Anyhow. More to come.

Normal Mapping the Time Device + basic Normal Mapping tips

Normal mapping in Blender always seemed such an awkward thing to accomplish. After reading into "mesh exploding" something finally clicked! If you want to know more about normal mapping I made a mini tutorial at the end of this article.

Now about the Time Device prop. I started modelling using the subdivision method as described in the scientist character modelling overview. This allowed me to make it look as nice as possible and not worry about re-topologising it later.

Once a Low poly mesh was produced, I removed the parts that can be duplicated and unwrapped it as efficiently as possible.

Next, and this is important, I made a copy of the low poly mesh and moved it far away from the original meshes. I then "exploded" both the high poly and original low poly meshes as described on some other sites. This essentially consists of taking all the parts that can be separated (anything that's a separate mesh, or can be made separate) and moving them far from their original positions.

Note: This is done for both high poly and low poly meshes making sure each corresponding high poly and low poly parts overlap.

This may seem crazy but remember that mesh copy I made? The non-exploded and exploded versions share the same UVs. This means that a normal map baked on the exploded version, will work on the non-exploded version and be glitch free! The original low poly mesh is left untouched and baked map can be applied to it!

Exploding the mesh reduces the interference between all the components and seems to produce much cleaner results.

Hope someone found this informative. Read on for more normal map related stuff!


Mini tutorial - Normal mapping Distance and Bias settings

This is something I only recently understood.

Lets make a normal map for this object (the picture shows the low poly and the high poly models):

I have identified the parts which will cause issues with the baking. In this case it happens to be the corners because the low poly deviates a lot from the high poly. 

The distance value represents an imaginary "cage" around every mesh comprising your model (or Object). This cage is both on the outside of the mesh and on the inside. The Distance value can only be made positive. Nevertheless the cage extends the same distance in the oposite direction. This ensure that no matter if the high poly extends outside or inside the low poly, the cage will still pick it up. The Bias is another imaginary cage, around your meshes, inside the first cage. The values are in Blender units (Bu).

So for each separate mesh in your model (within the same Object), you will get a separate cage with the same settings. You may need to explode your model as I explained above if this causes problems.

Anything outside the Distance (or cage) will not be baked. So when you get some solid colour artefacts in your bakes, this happens because the high poly mesh has polygons that extend beyond that distance. They intersect with the cage. You simply need to increase the Distance value until the cage is large enough that no intersections occur.

You can see that in order to resolve the detail of the high poly mesh, we need to set the distance parameter to be as close to the maximum distance between the high poly and low poly mesh. In this case, the maximum distance between the low and high poly models occurs at the corners and is around 0.1 Bu. So that's the minimum Distance value I can use for this low poly mesh.

The Bias value functions in a similar way. Anything inside the Bias cage will be projected onto the mesh to which that cage belongs to. Anything that extends beyond the Bias will not be baked.

 The first picture has a Bias of 0 and even though the cube is still within the Distance, it doesn't get baked to the normal map. This shows why the method above works .

The second picture shows that with some tweaked values you can project the cube onto the map. It also shows the Distance and Bias cages and clarifies what the Bias value does (please ignore the fact that I forgot an edge loop resulting in the corner of the main mesh being a little screwed up).

By making the Bias 0, the cube was totally ignored. Setting the Bias to the correct value (the distance from the surface of the main mesh, to a point beyond the cube) allowed the cube to be projected on the surface.

Note: in order for this to work, you need to increase the Distance value so as to include the cube within the Distance cage (see the previous picture).

In most cases the Bias value is not needed unless you want to project some objects onto your model e.g. you could project some screw holes, rivets, shirt buttons or anything that stands out from the surface of the mesh onto the normal map without needing extra geometry on the low poly mesh. This is good for many situations where you want to add small details without increasing poly count.

In conclusion here are some basic settings to keep in mind.

Single mesh where low poly matches high poly very closely:
Distance = 0.2
Bias = 0

Multiple meshes (say, box with complex surface plus screw holes around 0.1 Bu away from the main mesh)
distance = 0.2
Bias = 0.15

Note: these values will need to be tweaked because every model has a different scale etc.

I hope this was useful to some people! 

The Time Device

Today I did some texturing of a game prop. I made the high poly model and from that produced a low poly model. A normal map was then made from the high poly model.

I will detail how I did the normal mapping in another post, but I've found Blender to require a little bit of hacking to get going, but once you get the idea its pretty simple and relatively fast.

Anyway here's some screenshots.