<function name="Begin" parent="mesh" type="libraryfunc"> <description> Starts constructing a new 3D mesh constructed from a given number of primitives in a given primitive format. The resulting mesh can be stored in an <page>IMesh</page> if it is intended to be drawn multiple times or on multiple frames. </description> <realm>Client</realm> <args name="Building a Dynamic Mesh"> <arg name="primitiveType" type="number"> An enum that indicates what the format of the mesh's primitives will be. For a full list of the available options, see the <page>Enums/MATERIAL</page>. </arg> <arg name="primitiveCount" type="number"> The quantity of primitives this mesh will contain as a whole integer number. ⤶ The expected value of this argument is dependent on the primitive type used. ⤶ For a full list of the primitive counts expected by each primitive type, see <page>Enums/MATERIAL</page>. ⤶ </arg> </args> <args name="Building an IMesh"> <arg name="mesh" type="IMesh"> The <page>IMesh</page> that the created mesh will be stored in. </arg> <arg name="primitiveType" type="number"> An enum that indicates what the format of the mesh's primitives will be. For a full list of the available options, see the <page>Enums/MATERIAL</page>. </arg> <arg name="primitiveCount" type="number"> The quantity of primitives this mesh will contain, as a whole integer number. The quantity of primitives this mesh will contain as a whole integer number. ⤶ The expected value of this argument is dependent on the primitive type used. ⤶ For a full list of the primitive counts expected by each primitive type, see <page>Enums/MATERIAL</page>. ⤶ </arg> </args> </function> <example> <description> Draws a triangle near Vector( 0, 0, 0 ) in the map using a dynamic mesh, a dynamic mesh is good for animated meshes, or otherwise frequently changed rendered meshes. </description> <code> local mat = Material( "editor/wireframe" ) -- The material (a wireframe) local verts = { -- A table of 3 vertices that form a triangle { pos = Vector( 0, 0, 0 ), u = 0, v = 0 }, -- Vertex 1 { pos = Vector( 10, 0, 0 ), u = 1, v = 0 }, -- Vertex 2 { pos = Vector( 10, 10, 0 ), u = 1, v = 1 }, -- Vertex 3 } hook.Add( "PostDrawOpaqueRenderables", "MeshLibTest", function() render.SetMaterial( mat ) -- Apply the material mesh.Begin( MATERIAL_TRIANGLES, 1 ) -- Begin writing to the dynamic mesh for i = 1, #verts do mesh.Position( verts[i].pos ) -- Set the position mesh.TexCoord( 0, verts[i].u, verts[i].v ) -- Set the texture UV coordinates mesh.AdvanceVertex() -- Write the vertex end mesh.End() -- Finish writing the mesh and draw it end ) </code> </example> <example> <description>Draws a triangle near Vector( 0, 0, 0 ) in the map using a static mesh, that is, a mesh that is only created once, which is good for performance. </description> <code> local mat = Material( "editor/wireframe" ) -- The material (a wireframe) local obj = Mesh() -- Create the IMesh object local verts = { -- A table of 3 vertices that form a triangle { pos = Vector( 0, 0, 0 ), u = 0, v = 0 }, -- Vertex 1 { pos = Vector( 10, 0, 0 ), u = 1, v = 0 }, -- Vertex 2 { pos = Vector( 10, 10, 0 ), u = 1, v = 1 }, -- Vertex 3 } mesh.Begin( obj, MATERIAL_TRIANGLES, 1 ) -- Begin writing to the static mesh for i = 1, #verts do mesh.Position( verts[i].pos ) -- Set the position mesh.TexCoord( 0, verts[i].u, verts[i].v ) -- Set the texture UV coordinates mesh.AdvanceVertex() -- Write the vertex end mesh.End() -- Finish writing to the IMesh hook.Add( "PostDrawOpaqueRenderables", "MeshLibTest", function() render.SetMaterial( mat ) -- Apply the material obj:Draw() -- Draw the mesh end ) </code> </example>