Class: Meshes::Cube

Inherits:
Mesh
  • Object
show all
Defined in:
lib/belts_opengl/assets/meshes/cube.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Cube

Returns a new instance of Cube.



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# File 'lib/belts_opengl/assets/meshes/cube.rb', line 3

def initialize
  common_vertices = [
    # Back face
    [-HU, HU, -HU],
    [-HU, -HU, -HU],
    [HU, -HU, -HU],
    [HU, HU, -HU],

    # Front face
    [HU, HU, HU],
    [HU, -HU, HU],
    [-HU, -HU, HU],
    [-HU, HU, HU]
  ]

  vertices = [
    # Back face
    *common_vertices[0], *Vec3.back,
    *common_vertices[1], *Vec3.back,
    *common_vertices[2], *Vec3.back,
    *common_vertices[3], *Vec3.back,

    # Right face
    *common_vertices[3], *Vec3.right,
    *common_vertices[2], *Vec3.right,
    *common_vertices[5], *Vec3.right,
    *common_vertices[4], *Vec3.right,

    # Front face
    *common_vertices[4], *Vec3.forward,
    *common_vertices[5], *Vec3.forward,
    *common_vertices[6], *Vec3.forward,
    *common_vertices[7], *Vec3.forward,

    # Left face
    *common_vertices[7], *Vec3.left,
    *common_vertices[6], *Vec3.left,
    *common_vertices[1], *Vec3.left,
    *common_vertices[0], *Vec3.left,

    # Top face
    *common_vertices[7], *Vec3.up,
    *common_vertices[0], *Vec3.up,
    *common_vertices[3], *Vec3.up,
    *common_vertices[4], *Vec3.up,

    # Bottom face
    *common_vertices[1], *Vec3.down,
    *common_vertices[6], *Vec3.down,
    *common_vertices[5], *Vec3.down,
    *common_vertices[2], *Vec3.down
  ]

  indexes = (0..5).map do |i|
    stride = i * 4

    [
      stride, stride + 1, stride + 2,
      stride + 2, stride + 3, stride
    ]
  end.flatten

  super(vertices, indexes)
end