Class: Mittsu::SphereGeometry

Inherits:
Geometry
  • Object
show all
Defined in:
lib/mittsu/extras/geometries/sphere_geometry.rb

Instance Attribute Summary

Attributes inherited from Geometry

#bounding_box, #bounding_sphere, #colors, #dynamic, #face_vertex_uvs, #faces, #has_tangents, #id, #line_distances, #morph_colors, #morph_normals, #morph_targets, #name, #skin_indices, #skin_weights, #type, #uuid, #vertices

Instance Method Summary collapse

Methods inherited from Geometry

#apply_matrix, #center, #clone, #compute_bounding_box, #compute_bounding_sphere, #compute_face_normals, #compute_line_distances, #compute_morph_normals, #compute_tangents, #compute_vertex_normals, #dispose, #from_buffer_geometry, #merge, #merge_mesh, #merge_vertices, #to_json

Methods included from EventDispatcher

#add_event_listener, #dispatch_event, #has_event_listener, #remove_event_listener

Constructor Details

#initialize(radius = 50.0, width_segments = 8, height_segments = 6, phi_start = 0.0, phi_length = (::Math::PI * 2.0), theta_start = 0.0, theta_length = ::Math::PI) ⇒ SphereGeometry

Returns a new instance of SphereGeometry.



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# File 'lib/mittsu/extras/geometries/sphere_geometry.rb', line 6

def initialize(radius = 50.0, width_segments = 8, height_segments = 6, phi_start = 0.0, phi_length = (::Math::PI * 2.0), theta_start = 0.0, theta_length = ::Math::PI)
  super()

  @type = 'SphereGeometry'

  @parameters = {
    radius: radius,
    width_segments: width_segments,
    height_segments: height_segments,
    phi_start: phi_start,
    phi_length: phi_length,
    theta_start: theta_start,
    theta_length: theta_length
  }

  width_segments = [3, width_segments.floor].max
  height_segments = [2, height_segments].max

  _vertices = []
  uvs = []

  (height_segments + 1).times do |y|
    vertices_row = []
    uvs_row = []

    (width_segments + 1).times do |x|
      u = x / width_segments.to_f
      v = y / height_segments.to_f

      vertex = Vector3.new
      vertex.x = -radius * ::Math.cos(phi_start + u * phi_length) * ::Math.sin(theta_start + v * theta_length)
      vertex.y = radius * ::Math.cos(theta_start + v * theta_length)
      vertex.z = radius * ::Math.sin(phi_start + u * phi_length) * ::Math.sin(theta_start + v * theta_length)

      @vertices << vertex

      vertices_row << @vertices.length - 1.0
      uvs_row << Vector2.new(u, 1.0 - v)
    end

    _vertices << vertices_row
    uvs << uvs_row
  end

  height_segments.times do |y|
    width_segments.times do |x|
      v1 = _vertices[y][x + 1]
      v2 = _vertices[y][x]
      v3 = _vertices[y + 1][x]
      v4 = _vertices[y + 1][x + 1]

      n1 = @vertices[v1].clone.normalize
      n2 = @vertices[v2].clone.normalize
      n3 = @vertices[v3].clone.normalize
      n4 = @vertices[v4].clone.normalize

      uv1 = uvs[y][x + 1].clone
      uv2 = uvs[y][x].clone
      uv3 = uvs[y + 1][x].clone
      uv4 = uvs[y + 1][x + 1].clone

      if @vertices[v1].y.abs == radius
        uv1.x = (uv1.x + uv2.x) / 2.0
        @faces << Face3.new(v1, v3, v4, [n1, n3, n4])
        @face_vertex_uvs[0] << [uv1, uv3, uv4]
      elsif @vertices[v3].y == radius
        uv3.x = (uv3.x + uv4.x) / 2.0
        @faces << Face3.new(v1, v2, v3, [n1, n2, n3])
        @face_vertex_uvs[0] << [uv1, uv2, uv3]
      else
        @faces << Face3.new(v1, v2, v4, [n1, n2, n4])
        @face_vertex_uvs[0] << [uv1, uv2, uv4]
        @faces << Face3.new(v2, v3, v4, [n2.clone, n3, n4.clone])
        @face_vertex_uvs[0] << [uv2.clone, uv3, uv4.clone]
      end
    end
  end

  compute_face_normals
  @bounding_sphere = Sphere.new(Vector3.new, radius)
end