Before unwrapping a 3D mesh for texturing, you need to know what UV mapping is and a little about how it works. In this video, learn about what UV mapping does and why you need it for your meshes.
- [Instructor] Whether you have mastered Houdini's modeling tools and so, now, want to texture your newly-created assets or want to become a texture artist and so, need to understand UVWs in that context, the simple truth is that before jumping into any of Houdini's mapping tools, we first need to know what is meant by the term UVW or UV mapping coordinates. Well, simply put, UVW coordinates are one way of tackling a tricky problem in 3-D asset creation, and that is how to take the information contained inside one of Houdini's map types, be that a bitmap image or a mathematically-generated procedural, and then, apply that detail to the surface of a 3-D object in the scene.
Keeping in mind that we also need to be able to perform this type of operation in a predictable fashion, and it has to be usable inside a production situation. So, our application needs a system that can tell its various render engines, or its 3-D viewports, where on a geometric surface visual information found in a texture map ought to be placed. On top of that, the system would also need to be editable. In other words, the artist inputting and applying the texture map would need to have the ability to make artistic choices regarding how the visual information is displayed.
The solution? Houdini's UVW mapping system. Now, probably, the first thing we will want to know is what the letters U, V, and W actually stand for. Well, in short, these are designed to avoid confusion. They indicate the position and orientation of a map once it has been applied to an object's surface, in much the same way that we use the X, Y, and Z, or Cartesian coordinate system, to describe an object's position, orientation, and scale in 3-D space.
If the letters X, Y, and Z were used for both texture and object coordinates, well, I'm sure you can see the potential for confusion there, but why U, V, and W in particular? Well, quite simply, because they proceed X, Y, Z in the alphabet. Although, we do, of course, need to separate U, V, W coordinates from the Cartesian system because, even though they too, in a manner of speaking, indicate direction, they work in relation to the length and width of the map being applied, regardless of the orientation or size in 3-D space of the geometry to which the map is being applied.
Well, with that in mind then, let's move on to our next video and take a look at what UVW space is, how it works, and how it is represented and manipulated inside the Houdini application.
- UV mapping basics
- Controlling how UV mapping handles scale
- Displaying viewport maps correctly
- Testing and resetting UVs
- Choosing a texture type
- Mapping NURBS and Bézier surfaces
- Making UV seams
- Grouping, storing, and reusing UV seam selections
- Using seams with pelt mapping
- Selecting and manipulating UVs
- Sewing shared points
- Installing the Game Development Toolset