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You can create polygonal mesh forms. Because the faces of the mesh are planar, the mesh can only approximate curved surfaces.

You can use meshes if you need hiding, shading, and rendering capabilities that wireframe models cannot provide but do not need the physical properties that solid models provide (mass, volume, center of gravity, moments of inertia, and so on).

You can also use meshesto create geometry with unusual mesh patterns, such as a 3D topographical model of mountainous terrain.

The visual style controls how a mesh is displayed, either wireframe or shaded. (VISUALSTYLES command)

You can create several types of meshes.

▪ 3D face. 3DFACE creates a planar mesh with either three or four sides.

▪ Ruled mesh. RULESURF creates a polygon mesh representing theruled surface between two lines or curves.

▪ Tabulated mesh. TABSURF creates a polygon mesh representing a general tabulated surface defined by the extrusion of a line or curve (called a path curve) in a specified direction and distance (called a direction vector).

▪ Revolved mesh. REVSURF creates a polygon mesh approximating a surface of revolution by rotating a path curve or profile(lines, circles, arcs, ellipses, elliptical arcs, polylines, or splines, closed polylines, polygons, closed splines, or donuts) about a specified axis.

▪ Edge-defined mesh. EDGESURF creates a polygon mesh approximating a Coons surface patch mesh from four adjoining edges. A Coons surface patch mesh is a bicubic surface interpolated between four adjoining edges (which can be general spacecurves).

▪ Predefined 3D mesh. 3D creates three-dimensional polygon mesh objects in common geometric shapes, including boxes, cones, spheres, tori, wedges, and pyramids.

▪ General meshes. 3DMESH and PFACE create three-dimensional polygon mesh objects in any shape.

Understand Mesh Construction

The mesh density controls the number of facets, and is defined in terms of a matrix of M and Nvertices, similar to a grid consisting of columns and rows. M and N specify the column and row position, respectively, of any given vertex.

A mesh can be open or closed. A mesh is open in a given direction if the start and end edges of the mesh do not touch, as shown in the following illustrations.
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There are several methods for creating meshes.

Create a Ruled Mesh

With RULESURF,you can create a mesh between two lines or curves. You can use two different objects to define the edges of the ruled mesh: lines, points, arcs, circles, ellipses, elliptical arcs, 2D polylines, 3D polylines, or splines. Pairs of objects to be used as the “rails” of a ruled mesh must both be either open or closed. You can pair a point object with either an open or a closed object.
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You canspecify any two points on closed curves to complete RULESURF. For open curves, construction of the ruled mesh is based on the locations of the specified points on the curves.
[pic]
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Create a Tabulated Mesh

With the TABSURF command, you can create a mesh representing a general tabulated surface defined by a path curve and a direction vector. The path curve can be a line, arc, circle,ellipse, elliptical arc, 2D polyline, 3D polyline, or spline. The direction vector can be a line or an open 2D or 3D polyline. TABSURF creates the mesh as a series of parallel polygons running along a specified path. You must have the original object and the direction vector already drawn, as shown in the following illustrations.
[pic]

Create a Revolved Mesh

Use the REVSURF command tocreate a revolved mesh by rotating a profile of the object about an axis. REVSURF is useful for mesh forms with rotational symmetry.
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The profile is called a path curve, which can be any combination of lines, circles, arcs, ellipses, elliptical arcs, polylines, or splines, closed polylines, polygons, closed splines, or donuts.

Create an Edge-Defined Mesh

With the EDGESURF command, you...
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