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GFX.Mesh

Name Mandatory Description Default Type
⬅️ Input The input table containing Vertices and Indices keys with the relevent values to construct the mesh object. {Vertices: [Float2 Float3 Float4 Color] Indices: [Int]}
Output ➡️ The created mesh object. GFX.Mesh
Layout No The names for each vertex attribute. The sequence provided will also be the pattern that dictates how the sequence value of the Vertices key in the input table will be interpreted. none [String]
WindingOrder No Determines which side of the triangle is considered the front face. none WindingOrder

This shard creates a mesh object using the data provided in the Vertices and Indices keys of the input table.

Details

The sequence of strings given to the Layout parameter will be used as the pattern to interpret the sequence value in the Vertices key of the input table.

Consider the following example: 

{
    "Vertices": [
      @f3(-1.0 1.0 1.0) @color(0x000000)
      @f3(1.0 1.0 1.0) @color(0x0000ff)
      @f3(-1.0 -1.0 1.0) @color(0x00ff00)
      @f3(1.0 -1.0 1.0) @color(0x00ffff)
      @f3(-1.0 1.0 -1.0) @color(0xff0000)
      @f3(1.0 1.0 -1.0) @color(0xff00ff)
      @f3(-1.0 -1.0 -1.0) @color(0xffff00)
      @f3(1.0 -1.0 -1.0) @color(0xffffff)]
    "Indices": [
      0 1 2
      1 3 2
      4 6 5
      5 6 7
      0 2 4
      4 2 6
      1 5 3
      5 7 3
      0 4 1
      4 5 1
      2 3 6
      6 3 7
    ]
  }
  GFX.Mesh(Layout: ["position" "color"] WindingOrder: WindingOrder::CW) = mesh
The sequence in the Layout parameter will make it such that each pair of elements in the sequence represent a vertex, with the first value in the pair representing the vertex position and the second value represents the vertex colour. Thus element 1 and element 2 in the sequence repesent the first vertex, element 3 and element 4 represent the second vertex and so on and so forth.

Any string can be added to the sequence of string in the Layout parameter, however the following strings already have a set definition and will be interpreted accordingly: - "position" : Vertex position (usually 2D or 3D) - "color" : Vertex color - "normal" : Vertex normal (for lighting calculations) - "texCoord0" , "texCoord1" , "texCoord2" etc. : Texture coordinates - "tangent" : Tangent vector (for advanced lighting techniques)

The Shader.ReadInput shard can be used to read the values assigned to the strings specified in the Layout parameter. Shader.ReadInput(Name: "texCoord0") for example will read the texture coordinates of the current vertex set to texCoord0.

The sequence of indices in the Indices key of the input table will be used to draw the triangles that will make up the mesh, with each set of three indices representing a single triangle.

Consider the following example: 

{
    "Vertices": [
      @f3(-1.0 1.0 1.0) @color(0x000000)
      @f3(1.0 1.0 1.0) @color(0x0000ff)
      @f3(-1.0 -1.0 1.0) @color(0x00ff00)
      @f3(1.0 -1.0 1.0) @color(0x00ffff)
      @f3(-1.0 1.0 -1.0) @color(0xff0000)
      @f3(1.0 1.0 -1.0) @color(0xff00ff)
      @f3(-1.0 -1.0 -1.0) @color(0xffff00)
      @f3(1.0 -1.0 -1.0) @color(0xffffff)]
    "Indices": [
      0 1 2
      1 3 2
      4 6 5
      5 6 7
      0 2 4
      4 2 6
      1 5 3
      5 7 3
      0 4 1
      4 5 1
      2 3 6
      6 3 7
    ]
  }
  GFX.Mesh(Layout: ["position" "color"] WindingOrder: WindingOrder::CW) = mesh
In this example, the vertex with index 0, 1 and 2 will form the first triangle, the vertex with index 1, 3 and 2 will form the second triangle and so on and so forth.

The WindingOrder can either be WindingOrder::CW or WindingOrder::CCW. This will determine the orientation of the triangles that will be created from the indices.

Consider the following example: 

{
    "Vertices": [
      @f3(-1.0 1.0 1.0) @color(0x000000)
      @f3(1.0 1.0 1.0) @color(0x0000ff)
      @f3(-1.0 -1.0 1.0) @color(0x00ff00)
      @f3(1.0 -1.0 1.0) @color(0x00ffff)
      @f3(-1.0 1.0 -1.0) @color(0xff0000)
      @f3(1.0 1.0 -1.0) @color(0xff00ff)
      @f3(-1.0 -1.0 -1.0) @color(0xffff00)
      @f3(1.0 -1.0 -1.0) @color(0xffffff)]
    "Indices": [
      0 1 2
      1 3 2
      4 6 5
      5 6 7
      0 2 4
      4 2 6
      1 5 3
      5 7 3
      0 4 1
      4 5 1
      2 3 6
      6 3 7
    ]
  }
  GFX.Mesh(Layout: ["position" "color"] WindingOrder: WindingOrder::CW) = mesh
In this example, since WindingOrder is set to WindingOrder::CW, the vertices are interpreted in clockwise order when viewed from the front of the triangle. - Vertex 0: (-1.0, 1.0, 1.0) - Vertex 1: ( 1.0, 1.0, 1.0) - Vertex 2: (-1.0, -1.0, 1.0) In this case, if you were looking at the front face of the triangle, you would see the vertices arranged clockwise: 0 -> 1 -> 2. The normal of this triangle would point towards the viewer (out of the screen).

If WindingOrder is set to WindingOrder::CCW, the vertices are interpreted in counter-clockwise order when viewed from the front of the triangle. - Vertex 0: (-1.0, 1.0, 1.0) - Vertex 1: ( 1.0, 1.0, 1.0) - Vertex 2: (-1.0, -1.0, 1.0) However, now this order (0 -> 1 -> 2) is considered to be the back face of the triangle. The front face would be the reverse order: 2 -> 1 -> 0. The normal of this triangle would point away from the viewer (into the screen).

The mesh object output created by this shard can be passed to the Mesh parameter of the GFX.DrawablePass shard to be added to the render pipeline and subsequently rendered.