First, understand the UV map Uvs is a two-dimensional texture coordinate point that resides on a polygon mesh vertex, which defines a two-dimensional texture coordinate system called the UV texture space, which defines an axis with the U and v two letters. Used to determine how to place a texture image on a three-dimensional model surface.
Essentially, Uvs provides a connection between the model surface and the texture image, and Uvs is responsible for determining which vertex (pixels) on the texture image should be placed on the surface of the model, thus covering the entire texture onto the model. If there is no Uvs, the polygon mesh cannot be rendered out of the texture.
Typically, when you create a Maya original object, Uvs is generally created automatically (there is a Create Uvs option on the creation parameters panel, which is checked by default), but in most cases we still need to reschedule Uvs because Uvs does not automatically update the location when editing the model.
rearranging the Uvs is usually done after the model is completely done and before the texture map is specified. In addition, any modifications to the model can cause the dislocation of the model vertices to the uvs, resulting in an error in the texture map. For more highlights, please click here ."Dog Planing Learning net"
Second, UVs and texture mapping NURBs surface and polygon mesh mapping mechanism, the NURBS surface of the UV is built-in (has been automatically defined U, V), these Uvs can not be edited, moving the CV will affect texture mapping. the Uvs of polygons, which do not exist at first, must also be explicitly created and subsequently modified further.
Third, UV map the process of creating a Uvs for a surface is called a UV map (UV mapping). This process includes creating and editing. The result is a clear determination of how the image is displayed on a three-dimensional model, and the proficiency of the technique directly affects the final performance of the model.
Iv. creation of Uvs
There are many Uvs creation tools in Maya: Automatic UV tools, flat UV tools, cylindrical UV tools, spherical UV tools, user-defined UV tools, and more. Each creation tool uses a predetermined rule to project UV texture coordinates onto the model surface, automatically creating a texture image associated with the surface. In General, the auto-generated Uvs must also be further edited using the UV editor to achieve the desired effect. because each modification to the model (such as squeezing, zooming, adding, deleting, and so on) can cause Uvs dislocation, the best workflow is to create a UVS after the model is fully designed.
v. Observation and evaluation of UVS
Once you have created a Uvs for a model, you can edit it using the UV editor. This editor allows you to observe the UV coordinate point and its relationship to the texture image on a two-dimensional plane, and to manually edit the Uvs and its various elements.
in general, the UVS generated by default using the Create tool may not meet our needs, so you can observe the evaluation with your eyes in the UV editor, and manually adjust the position of the Uvs (rearrange).
the reference principle for adjusting the Uvs is to trust the texture image that eventually needs to be mapped. It can also be said that different images require different Uvs locations.
There are several situations that need to be adjusted using the UV editor:1, when the final image to be affixed to the model is determined, you may need to adjust the UV (and even in some cases to adjust the model grid) to fit that image. 2, want to use an image repeated multiple times. For example a brick wall. 3, when the use of automatic creation of Uvs. Automatically created Uvs always produce multiple surface-based, detached UV meshes, so you may need to rearrange or stitch some of the detached Uvs. 4. When the map on the model surface is severely distorted and stretched, you may need to expand and loosen some Uvs (Unfold and Relax) in the UV editor. Note that to create the best Uvs for a model, it may take several attempts and a different UV creation method.
Six, UV mapping tips Maya provides many tools for creating and editing Uvs, where the UV editor is the most important tool.
knowing how to find the best UV for an existing image is a very important technique, and here are some basic guidelines:1, maintain the range of Uvs coordinate value in 0-1in the UV editor, UV space is displayed as a grid marker with a working area of 0 to 1. By default, Maya automatically sets the value of Uvs to 0-1 during the UV creation process. However, after the Uvs are moved and scaled, the Uvs may be placed outside of 0-1. In most cases, the UV value should be kept within 0-1. When the UV value exceeds 0-1, the texture image appears duplicated or rounded. For more highlights, please click here ."Dog Planing Learning net"
2. Eliminate the overlap of UV shellsa mesh formed by connecting a UV point to each other is called a UV shell (UV shell). In the UV editor, if a UV shell overlaps, an image repetition occurs at the corresponding vertex part of the model. This overlap should usually be eliminated unless there is a special need. For example, if a model has two different parts with the same image, then the UV shells of the two parts can be placed on the image.
3, the correct arrangement between the UV shell intervalthe interval between two UV shells is also an important consideration. They cannot be too close, otherwise the image content of the other UV shell is rendered when rendering.
4, try to use capture Uvswhen editing Uvs, similar to editing elements in a scene, you can also use a variety of snapping methods to control Uvs. You can snap to background gridlines, other UV points, and image pixel points (you need to enlarge the editing area by N times to feel this capture).
vii. Introduction of UV editor There are several ways to open the UV Editor: Use window > UV Texture Editor, or edit UVs > UV Texture Editor, or panels > Panel > Uvtextu in the View menu Re Editor. Explains that the UV editor is a very important editor. in the UV editor, you can view and interactively edit texture coordinates (UVs). Select, move, scale, and modify UV topologies, as well as display background texture images as a reference for adjustment. UV Editor and Scene view, you can display the selected Uvs and the corresponding vertex. using many of the tools included with the UV editor, you can effectively edit Uvs. such as rotation and flipping, cutting and stitching, etc., can also output an edited Uvs layout as an image, and then use software such as PS to create a texture map. Note that there are some tools in the UV Editor in the main menu of edit Uvs. The view of the UV editor can also be moved and scaled using shortcuts (mouse wheel zoom, ALT + middle key move). There is also a right-click marker menu in the UV editor. It includes almost all of the operations.
Eight, UV set you can create multiple UV permutation schemes for the same model (unlimited quantity), each of which is called a UV set. UV sets are useful when several different UV layouts are required for a model. For example, you want to create a brick wall with some graffiti patterns above. You can use a texture as a brick, another texture as a doodle, and you can use a different UV layout (UV set) for both textures if the brick texture needs to be repeated and graffiti is not required. For more highlights, please click here ."Dog Planing Learning net"
the key steps for using UV sets are:1. Assign multiple textures to the material. If you can specify a color texture and a transparency texture for a material. In addition, you can specify a hierarchical texture for a single property, such as a color. 2. Create a UV set with different layouts (there is a UV set option in the Create parameter). 3. Use the relationship editor to associate textures with UV sets.
Nine, create a planar UV map maps Uvs to the model surface through a plane. The surface of the model is preferably relatively flat, or at least one angle of the camera can be seen at all. Typically, this technique creates a UV shell that overlaps and looks like a simple UV shell. Therefore, you should use Edit UVs > layout to separate the overlapping UV shells when you are finished creating them.
The best Plane texturing Tools Tool assigns Uvs to a polygon (a polygon selected beforehand through a vertex). You can select faces before using the best planetexturing tool tools, or you can use the Bestplane texturing Tools tool to choose which faces you want to map. 1, choose a model to map a face;2, use create UVs > Best Plane texturing tool tools;3, click on other faces to add to the selection, note, can not be selected, can only be selected with a click. Press ENTER after selecting. 4. Select three or more vertices (you can switch to vertex selection mode). -This may be used to determine the main plane. 5. Press ENTER again. The creation is complete. Go to the UV editor to view and edit the created Uvs. create a planar UV map (based on the camera plane)The above example determines a map master plane with the selected vertex, and now uses the camera plane as the main plane of the UV map. 1. Select one or several faces on the model that you want to map; (not selected will not participate in the layout)2, scroll the view, so that the face toward their own, or, simply switch into the orthogonal view, so that it completely aligned with themselves;3. Using Create UVs > Create UVs Based on camera tool, the creation is complete. Go to the UV editor to view and edit the created Uvs.
10. Create a planar UV map (based on a controllable plane) 1. Choose a face that you want to map;2. Open Create UVs > Planar Mapping > Parameter box, in fit projection to, if you choose best Plane, create a mapping plane based on the one you just selected; If you choose bounding box, Creates a model-based box plane as the mapping plane. 3, click Project, create a UV layout, and a manual regulator can be adjusted to make some simple adjustment;4, finally into the UV editor for complex adjustment.
11. Some description of the planar UV map1. Planar maps can create shared, overlapping uvs that look like texture boundaries. Open display> polygons > Texture Border Edges (show texture boundaries), you can see this boundary clearly. (or by displaying the border icon in the UV editor). 2, the sharing, overlapping UVs may cause seam problems, solve this problem can be manually separated UVs (with edit uvs> layout > Parameter box, set Separateshells to Folds,shell layout along U or into Square). 3, if you want to create a planar UV map for multiple models at once, you can choose to combine these models (combine), create Uvs, and then separate them (separate); otherwise, you can create them one by one. 4, if a model is a complex organic organ, and you want to map a map, the planar map may produce overlapping and distortion, at this point, you can consider the use of other mapping technology.
12, cylindrical UV map creates a UV layout based on a cylinder that wraps around the mesh of the model. The model is best to have no protrusion or voids. 1. Select the face you want to map .2. Using the Create UVs > Cylindrical mapping tool,3, using manual controller to operate the cylindrical shape;4, finally in the UV editor further editing.
13, spherical UV map based on a ball, the UV layout is generated along with wrapping around the model grid. The model is best to have no protrusion or voids. 1. Select the face you want to map .2. Using the Create UVs > Spherical mapping tool,3, using manual controller to operate the cylindrical shape;4, finally in the UV editor further editing.
14. Automatic UV mapping The UV layout is automatically found and determined by the system for the shape of the model, and multiple mapping planes may be used (resulting in multiple UV shells). For complex models and with empty models, it is very effective to use automatic UV mapping. in further operation, the separated shells may need to be stitched.
you can determine the number of mapping planes, and you can use an object in the scene as the mapping plane (via load Projection). 1. Select a model and open its UV editor at the same time;2, use create UVs > Automatic Mapping > Parameter box, set the parameters;3. Click Project. Use manual adjuster adjustment (the regulator can be recalled again in the Channel bar). 4, use the UV editor to further adjust.
15. User-defined UV mapping a mapping plane specified by the user to create a UV layout. Standard requirements for mapping objects:1, the object that is used as user Custom mapping must have UV texture coordinates;2, recommended this object is composed of separated faces. For example, if you want to use a primitive polygons as a mapping object, it must first detach the mesh with mesh > extract. (Do not use NURBS and subdivision surfaces as mapping objects). 3. This object determines the location and shape of the mapping plane when the UV layout is created in the future;4. The maximum number of faces of this object cannot exceed 31.
Operation Method:1. Select a model to map, and open its UV editor;2. Open Create UVs > Automatic Mapping > Parameter box, tick load Projection, enter the name of the mapping object you want to use in the input box, or select the object in the scene and click Load Selected loading;3. Click Project. Use manual adjuster adjustment (the regulator can be recalled again in the Channel bar). 4, use the UV editor to further adjust.
16, confirm the UV placement when creating a UV layout, how do you confirm that they are positioned correctly? One way to confirm this is to specify a material that contains textures to the model. Confirm by observing the texture. Maya provides a quick way to observe textures by opening create UVs > Assign Shader to each Projection,maya automatically creating a "Defaultpolygonshader" Material (it contains a checkerboard texture) and is assigned to the model that is creating the Uvs (the material is also added to the node of the model, so you can also change other textures on that node). By default, the method of quickly observing textures is closed.
17. Migrating a UV layout between two models typically migrations are used in this scenario: when creating a UV layout for a complex model, copy the complex model, smooth its mesh with a smooth tool (avoid overlapping uvs), and then create a UV layout on it, then migrate the layout to a complex model. 1, copy model;2. Use mesh > Average Vertices > Parameter box to smooth. (Note that this smoothing technique does not delete vertices); For best results, the tool can be reused multiple times. 3. Create a UV layout for this smooth model, then adjust until satisfied;
Unity3d Game Development UV Mapping Tutorial
