Represents a straight ribbon-shaped [PrimitiveMesh] with variable width. [RibbonTrailMesh] represents a straight ribbon-shaped mesh with variable width. The ribbon is composed of a number of flat or cross-shaped sections, each with the same [member section_length] and number of [member section_segments]. A [member curve] is sampled along the total length of the ribbon, meaning that the curve determines the size of the ribbon along its length. This primitive mesh is usually used for particle trails. $DOCS_URL/tutorials/3d/particles/trails.html $DOCS_URL/tutorials/3d/particles/index.html Determines the size of the ribbon along its length. The size of a particular section segment is obtained by multiplying the baseline [member size] by the value of this curve at the given distance. For values smaller than [code]0[/code], the faces will be inverted. The length of a section of the ribbon. The number of segments in a section. The [member curve] is sampled on each segment to determine its size. Higher values result in a more detailed ribbon at the cost of performance. The total number of sections on the ribbon. Determines the shape of the ribbon. The baseline size of the ribbon. The size of a particular section segment is obtained by multiplying this size by the value of the [member curve] at the given distance. Gives the mesh a single flat face. Gives the mesh two perpendicular flat faces, making a cross shape.