Mesh from Strands Modifier 

This modifier converts strands from hair state into mesh state. It is to be used in conjunction with (above in the stack) the change width modifier, which can specify hair radius. There are a number of parameters that control mesh creation. There are three main types of meshes that can be generated from hair:

  1. Cylindrical hair (can be rendered from all angles, great for high quality hair)
    Prismatic meshes are cylindrical N-sided structures that encapsulate each strand. Because they can be viewed from all directions, they can be rendered as they are or collapsed into baked meshes. This is often the best choice for strands that demand quality over quantity. Some examples include cat whiskars and lizard tails. Rendering very thin cylindrical hair usually causes artifacts, but these can be fixed with increasing sampling per pixel in your renderer.
    Cylindrical hair has to be rendered with one of Max's shaders (such as standard) because the normals are generated away from the surface.
  2. Billboarded hair (fast and cheap to render, great for dense thin hair, can be used with Ornatrix shaders)
    Billboarded hair primitives are faces, one per segment, that form sprites which always face the camera. Since hair in nature is cylindrical, camera-facing billboards fill the task of rendering hair very well. They are cheap to generate and render, however one downside is the fact that they're not cylindrical and sometimes can't be used for things like whiskars, like prismatic mesh primitive. Billboarded hair can be oriented in any direction as well as controlled by a map to produce things like grass and tree leafs.
  3. Proxy hair (use any arbitrary set of objects as hair. Great for managing large leafy scenes such as forests or bird feathers)
    Proxy mesh-based hair allows you to take any mesh object (or a set of objects) in the scene and use it as a strand. Ornatrix will literally stretch the object along the strand and deform it using strand transforms. There are options to inherit hair's shape, thickness, orientation, and UVs for any number of arbitrary mesh objects. If multiple objects are added to the list, they will be randomly assigned to each strand. Randomness can be controlled through a seed parameter.
    Orientation can be easily controlled with same parameters as used for billboarded hair. Proxy hair is great for things like bird feathers, tree leafs, and forests.
    • Texture Coordinates and Mapping Channels
      If "Per Strand UV Coords." option is checked then proxy mesh generated for each strand will reuse the same texture coordinates as the incoming proxy mesh. If that option is off, then each mesh will have the texture coordinate of the underlying distribution mesh at each strand's position. This, in addition to adding multiple mapping channels with their own settings, allows using textures which vary with the surface of the distribution mesh and also with the strand geometry.
    • Material ID Assignment
      • If "Scatter Randomly" option is off, a material ID will be assigned to each generated strand mesh according to the incoming proxy mesh which was used. For example, if a strand uses a mesh which is the 2'nd on the list, it will have material ID 2 in the resulting mesh. This allows using a sub-object material to assign different materials to different generated strands.
      • If "Scatter Randomly" option is on, a material ID will be generated randomly for each mesh, or derived from the provided scatter map and/or strand group, similar to billboard hair.
    • Mesh Twisting
      The proxy mesh is stretched along the source strand, however, determining its twist can sometimes produce unwanted results. Use the <a href="orientBasedOnStrand.html">orient based on strand</a> option to fix this problem. When this option is on the proxy mesh will always be oriented based on the strand's current shape instead of a global twist angle.
 

Parameters 

  • Strand Group
    Allows you to isolate the effect of this modifier by selecting a Strand Group created in the Edit Guides modifier.
  • Tangent normals
    When on, render normals generated on the mesh are actually hair tangents (perpendicular to normals). This option should be used when using Ornatrix shaders to render the hair.
  • Face camera
    When using billboarded hair, during a render this option will orient all billboards to face the camera.
  • Number of sides
    When using cylindrical hair this option sets number of sides of each hair cylinder. Total number of triangles (faces) in the mesh then becomes NumStrands * ( PointsPerStrand - 1 ) * NumSides * 2
  • Uniform scale
    If this option is on, generated proxy meshes will be scaled down uniformly (along all -X, Y, and Z axes) based on strand length.
  • Inherited properties
    Determine which hair properties are inherited from underlying hair, and which properties are ignored. For example, if you wish for your objects not to deform with the strand length-wise, turn off the shape inheritance.
  • Conform To Surface
    When on, the roots of the hair meshes will be aligned with the distribution mesh surface. This causes the hairs to appear to be glued to the surface.
    • Ignore Surface (Default)
      Base of hair meshes will be aligned with the hair's tangent
    • Surface Normal
      Base of hair meshes with be aligned with the base surface