Many users are used to learn one by one all tools of a software ,but it is not really a good idea,because even though you can manipulate all tools,but you will be puzzled, you don't still know when and how and where to use them ,and don't know why the tools exist.

As we know, terrain landscape modeling is a very hard work,it is not like surface modeling which can use few control points to control complex modeling,and not like building modeling which can be freely pick a part of entire model to modify ,because it is generally regular .Terrain landscape modeling need often disruptive modification on terrain.For example,you are going to make roads on terrain,where are you begin?Use boolean and comform deform object as before? Another example,if your modeling has been completed ,but you need to hack a clearing from terrain to place a building by the side of the road ,which tool will you first call in mind? Some users generate curb,sideway and stone paving ,but roads are still flat,how to do after ajusting level difference of roads? how to do in next connecting work to terrain?

 

So ,it is impossible to modeling for terrain landscape as modeling for other type of scense,we need a new completely different idea to guide us to find an efficent workflow,which can avoid plenty of unusful jobs.The peculiarity of terrain landscape modeling decide there is only one workable thread,which has been write in the article MAIN THREAD OF MODELING TERRAIN LANDSCAPE .It is a very important arcticle. It is very necessary to read the arcticle before learn TerrainAxe. The thread is the most direct and efficient we can find,because of which every tool exist.Follow the thread to search tools you desired and understand them,thus you can freely use TerrainAxe .

 

Why use a software like Civil3D to modeling terrain landscape?Maybe somebody ask.It is really a powerful software,but first of all,this type of automate software need complete data ,but the data we can have is generally insufficent;Also we have many individuation requirements,which can be solved by ajust data or parameters.Only preparing  many individe tools  to  let users freely combinate them can   meet our defferent requirements,this is also the time to show the power of TerrainAxe.

Hope everyone who is interested in TerrainAxe can realize earlier the value of the software.

A tutorial and its 3dsmax file were also provided,Basic Tutorial---Make Roads Through Terrain.

Facing a terrain project,where should you begin ?It is really confusing, but there is still one thing we can confirm :All works of the terrain modeling base on some roads,that is to say that all things is meaningful only when the roads is fixed. If the road is modified ,all things connected with it will have to be adjusted.For example,if the curbs of a road is first created  and then you want to change the elevation of the road,previous work will be wasted.So,the most logical and resonable steps should be :At first ,build your road as accuratly as possible ,then think about how to add new faces to connect the roads and the terrains.This is also the basic thinking that TerrainAxe was designed basd on.

Generally,three issues are the most focused by 3D modeling artists:

Good topology

Make slopes and smooth roads

Connect roads and terrains

First of all,we talk about the most concerned question for 3D modeling artists :how to connect roads and terrain

Connect roads and terrains

There are two main ways to connect roads and terrains:

For an existed terrain object(such as a terrain mesh built from contour lines or some DEM data),thinking about the work flow:first ,delete the faces covered by the roads,then we can get some borders,with the borders and that of the roads ,create a big polygon face and subdivide it,then we will complete connecting.

In TerrainAxe,CapEdges,FreePoly can use an unclosed border to create a polygon,StitchVerts and Triangulate(Faces) can  cut polygons.

We can also use StitchPoly directly to create polygons to  connect borders of  a terrain and a road.

2.For those areas enclosed or semi-enclosed  by  roads,maybe the original terrain is missing or un-useful,a new terrain need to be re-created. Thus you can cap these areas to create a new polygon,then use Slice to cut and get grid-like topology,then relax them or paint desired appearance with 3dsmax's brush tools .

the way is also suit for the first situation.If you don't like the topology created with contour lines,you can use MoveVerts to conform vertices of the grid-like faces to the original terrain.So,you don't need  to stitch them.

Topologize

Topologizing is very important.To present accurate slopes and road levles, topologizing or re-topologizing   is necessary.There are some requirements for topologizing:

A road should be made up of regulate quad polygons as much as  possible,as shown  below in left picture;Some ground pavement need some cutting operations to make the polygon topology more reasonable;

Narrow and long triangles should be avoided as much as possible. The more reasonable topology, the better the effect at render time, as shown below in the right picture.

To meet the above requirements,many cutting operations are needed.In TerrainAxe ,there are many cutting tools to such as CutPerToEdge,CutByAgl,Cut2Verts and StitchVerts,and so on

Slope modeling and road smoothing

Make a Slope

Such a tool is indispensable:when vertices of surface fall to a slope,only z coordinates are modified but xy coordinates keep unchanged,that is ,make vertices align to slope plane along Z axis ,or the structure in top view will be damaged.MoveVerts can do this.

Smooth Roads

To present road levels and get a natural appearance,the section of a road need to keep horizontal,and can't be sticked to the terrain like a clothe .

So an ideal tool  should be able to output a smooth transition like a curve and meanwhile be able to  map  the evelation data of one side of the road to that of the other side,

When smoothing a road ,continous  edges  can be used to represent a range of  the  road  and the vertices with different z coordinates  to express  different  elevations 

you can use SMRoad(linear),SMRoad(curve),SMRoad(npts),SMRoad(blur)  to complete this work.

SMRoad(Splines)  uses a more advanced way to smooth a road in which you can ajust knots of splines to control the transition.

The article describe  several  main issuses of terrain modeling from the outer frame,it should be as a main direction.Hope  readers can get desired help and have a good beginning.