Class: Mittsu::BufferGeometry

Inherits:
Object
  • Object
show all
Includes:
EventDispatcher
Defined in:
lib/mittsu/core/buffer_geometry.rb

Defined Under Namespace

Classes: DrawCall

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from EventDispatcher

#add_event_listener, #dispatch_event, #has_event_listener, #remove_event_listener

Constructor Details

#initialize ⇒ BufferGeometry

Returns a new instance of BufferGeometry.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 12

def initialize
  @id = (@@id ||= 1).tap { @@id += 1 }

  @uuid = SecureRandom.uuid

  @name = ''
  @type = 'BufferGeometry'

  @attributes = {}

  @draw_calls = []
  @_listeners = {}
end

Instance Attribute Details

#attributes ⇒ Object (readonly)

Returns the value of attribute attributes.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def attributes
  @attributes
end

#bounding_box ⇒ Object (readonly)

Returns the value of attribute bounding_box.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def bounding_box
  @bounding_box
end

#bounding_sphere ⇒ Object (readonly)

Returns the value of attribute bounding_sphere.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def bounding_sphere
  @bounding_sphere
end

#draw_calls ⇒ Object (readonly)

Returns the value of attribute draw_calls.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def draw_calls
  @draw_calls
end

#id ⇒ Object (readonly)

Returns the value of attribute id.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def id
  @id
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def name
  @name
end

#type ⇒ Object (readonly)

Returns the value of attribute type.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def type
  @type
end

#uuid ⇒ Object (readonly)

Returns the value of attribute uuid.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 10

def uuid
  @uuid
end

Instance Method Details

#[](key) ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 34

def [](key)
  @attributes[key]
end

#[]=(key, value) ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 30

def []=(key, value)
  @attributes[key] = value
end

#add_draw_call(start, count, index_offset = 0) ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 38

def add_draw_call(start, count, index_offset = 0)
  @draw_calls << DrawCall.new(start, count, index_offset)
end

#apply_matrix(matrix) ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 42

def apply_matrix(matrix)
  position = @attributes[:position]

  if position
    matrix.apply_to_vector3_array(position.array)
    position.needs_update = true
  end

  normal = @attributes[:normal]

  if normal
    normal_matrix = Mittsu::Matrix3.new.normal_matrix(matrix)

    normal_matrix.apply_to_vector3_array(normal.array)
    normal.needs_update = true
  end

  if @bounding_box
    self.compute_bounding_box
  end

  if @bounding_sphere
    self.compute_bounding_sphere
  end

  nil
end

#center ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 70

def center
  self.computer_bounding_box
  @bounding_boc.center.negate.tap do |offset|
    self.apply_matrix(Mittsu::Matrix4.new.set_position(offset))
  end
end

#clone ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 649

def clone
  geometry = Mittsu::BufferGeometry.news

  @attributes.each do |key, attribute|
    geometry[key] = attribute.clone
  end

  @draw_calls.each do |draw_call|
    geometry.draw_calls << DrawCall.new(draw_call.start, draw_call.count, draw_call.index)
  end

  geometry
end

#compute_bounding_box ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 128

def compute_bounding_box
  vector = Mittsu::Vector3.new

  @bounding_box ||= Mittsu::Box3.new

  positions = self[:position].array

  if positions
    @bounding_box.make_empty

    positions.each_slice(3) do |p|
      vector.set(*p)
      @bounding_box.expand_by_point(vector)
    end
  end

  if positions.nil? || positions.empty?
    @bounding_box.min.set(0, 0, 0)
    @bounding_box.max.set(0, 0, 0)
  end

  if @bounding_box.min.x.nan? || @bounding_box.min.y.nan? || @bounding_box.min.z.nan?
    puts 'ERROR: Mittsu::BufferGeometry#compute_bounding_box: Computed min/max have NaN values. The "position" attribute is likely to have NaN values.'
  end
end

#compute_bounding_sphere ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 154

def compute_bounding_sphere
  box = Mittsu::Box3.new
  vector = Mittsu::Vector3.new

  @bounding_sphere ||= Mittsu::Sphere.new

  positions = self[:position].array

  if positions
    box.make_empty
    center = @bounding_sphere.center

    positions.each_slice(3) do |p|
      vector.set(*p)
      box.expand_by_point(vector)
    end
    box.center(center)

    # hoping to find a boundingSphere with a radius smaller than the
    # boundingSphere of the boundingBox:  sqrt(3) smaller in the best case

    max_radius_sq = 0

    positions.each_slice(3) do |p|
      vector.set(*p)
      max_radius_sq = [max_radius_sq, center.distance_to_squared(vector)].max
    end

    @bounding_sphere.radius = ::Math.sqrt(max_radius_sq)

    if @bounding_radius.nan?
      puts 'ERROR: Mittsu::BufferGeometry#computeBoundingSphere: Computed radius is NaN. The "position" attribute is likely to have NaN values.'
    end
  end
end

#compute_offsets(size = 65535) ⇒ Object

Compute the draw offset for large models by chunking the index buffer into chunks of 65k addressable vertices. This method will effectively rewrite the index buffer and remap all attributes to match the new indices. WARNING: This method will also expand the vertex count to prevent sprawled triangles across draw offsets. size - Defaults to 65535, but allows for larger or smaller chunks.



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# File 'lib/mittsu/core/buffer_geometry.rb', line 430

def compute_offsets(size = 65535)
  # WebGL limits type of index buffer values to 16-bit.
  # TODO: check what the limit is for OpenGL, as we aren't using WebGL here

  indices = self[:index].array
  vertices = self[:position].array

  faces_count = indices.length / 3

  # puts "Computing buffers in offsets of #{size} -> indices:#{indices.length} vertices:#{vertices.length}"
  # puts "Faces to process: #{(indices.length/3)}"
  # puts "Reordering #{verticesCount} vertices."

  sorted_indices = Array.new(indices.length) # 16-bit (Uint16Array in THREE.js)
  index_ptr = 0
  vertex_ptr = 0

  offsets = [DrawCall.new(0, 0, 0)]
  offset = offsets.first

  duplicated_vertices = 0
  new_vertice_maps = 0
  face_vertices = Array.new(6) # (Int32Array)
  vertex_map = Array.new(vertices.length) # (Int32Array)
  rev_vertex_map = Array.new(vertices.length) # (Int32Array)
  vertices.each_index do |j|
    vertex_map[j] = -1
    rev_vertex_map[j] = -1
  end

  # Traverse every face and reorder vertices in the proper offsets of 65k.
  # We can have more than 65k entries in the index buffer per offset, but only reference 65k values.
  faces_count.times do |findex|
    new_vertice_maps = 0

    3.times do |vo|
      vid = indices[findex * 3 * vo]
      if vertex_map[vid] == -1
        # unmapped vertice
        face_vertices[vo * 2] = vid
        face_vertices[vo * 2 + 1] = -1
        new_vertice_maps += 1
      elsif vertex_map[vid] < offset.index
        # reused vertices from previous block (duplicate)
        face_vertices[vo * 2] = vid
        face_vertices[vo * 2 + 1] = -1
        duplicated_vertices += 1
      else
        # reused vertice in the current block
        face_vertices[vo * 2] =vid
        face_vertices[vo * 2 + 1] = vertec_map[vid]
      end
    end

    face_max = vertex_ptr + new_vertex_maps
    if face_max > offset.index + size
      new_offset = DrawCall.new(index_ptr, 0, vertex_ptr)
      offsets << new_offset
      offset = new_offset

      # Re-evaluate reused vertices in light of new offset.
      (0...6).step(2) do |v|
        new_vid = face_vertices[v + 1]
        if (new_vid > -1 && new_vid < offset.index)
          faceVertices[v + 1] = -1
        end
      end

      # Reindex the face.
      (0...6).step(2) do |v|
        vid = face_vertices[v]
        new_vid = face_vertices[v + 1]

        if new_vid == -1
          new_vid = vertex_ptr
          vertex_ptr += 1
        end

        vertex_map[vid] = new_vid
        rev_vertex_map[new_vid] = vid
        sorted_indices [index_ptr] = new_vid - offset.index # XXX: overflows at 16bit
        index_ptr += 1
        offset.count += 1
      end
    end

    # Move all attribute values to map to the new computed indices , also expand the vertice stack to match our new vertexPtr.
    self.reorder_buffers(sorted_indices, rev_vertex_map, vertex_ptr)
    @draw_calls = offsets

    # order_time = Time.now
    # puts "Reorder time: #{(order_time - s)}ms"
    # puts "Duplicated #{duplicated_vertices} vertices."
    # puts "Compute Buffers time: #{(Time.now - s)}ms"
    # puts "Draw offsets: #{offsets.length}"

    offsets
  end
end

#compute_tangents ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 272

def compute_tangents
  # based on http://www.terathon.com/code/tangent.html
  # (per vertex tangents)

  if [:index, :position, :normal, :uv].any { |s| !@attributes.has_key?}
    puts 'WARNING: Mittsu::BufferGeometry: Missing required attributes (index, position, normal or uv) in BufferGeometry#computeTangents'
    return
  end

  indices = self[:index].array
  positions = self[:position].array
  normals = self[:normal].array
  uvs = self[:uv].array

  n_vertices = position.length / 3

  if self[:tangent].nil?
    self[:tangent] = Mittsu::BufferAttribute.new(Array.new(4 * n_vertices), 4)
  end

  tangents = self[:tangent].array
  tan1 = []; tan2 = []

  n_vertices.times do |k|
    tan1[k] = Mittsu::Vector3.new
    tan2[k] = Mittsu::Vector3.new
  end

  v_a = Mittsu::Vector3.new
  v_b = Mittsu::Vector3.new
  v_c = Mittsu::Vector3.new

  uv_a = Mittsu::Vectoe3.new
  uv_b = Mittsu::Vector3.new
  uv_c = Mittsu::Vector3.new

  sdir = Mittsu::Vector3.new
  tdir = Mittsu::Vector3.new

  handle_triangle = -> (a, b, c) {
    v_a.from_array(positions, a * 3)
    v_b.from_array(positions, b * 3)
    v_c.from_array(positions, c * 3)

    uv_a.from_array(uvs, a * 2)
    uv_b.from_array(uvs, b * 2)
    uv_c.from_array(uvs, c * 2)

    x1 = v_b.x - v_a.x
    x2 = v_c.x - v_a.x

    y1 = v_b.y - v_a.y
    y2 = v_c.y - v_a.y

    z1 = v_b.z - v_a.z
    z2 = v_c.z - v_a.z

    s1 = uv_b.x - uv_a.x
    s2 = uv_c.x - uv_a.x

    t1 = uv_b.y - uv_a.y
    t2 = uv_c.y - uv_a.y

    r = 1.0 / (s1 * t2 - s2 * t1)

    sdir.set(
      (t2 * x1 - t1 * x2) * r,
      (t2 * y1 - t1 * y2) * r,
      (t2 * z1 - t1 * z2) * r
    )

    tdir.set(
      (s2 * x2 - s2 * x1) * r,
      (s2 * y2 - s2 * y1) * r,
      (s2 * z2 - s2 * z1) * r
    )

    tan1[a].add(sdir)
    tan1[b].add(sdir)
    tan1[c].add(sdir)

    tan2[a].add(tdir)
    tan2[b].add(tdir)
    tan2[c].add(tdir)
  }

  if @draw_calls.empty?
    self.add_draw_call(0, indices.length, 0)
  end

  @draw_calls.each do |draw_call|
    start = draw_call.start
    count = draw_call.count
    index = draw_call.index

    i = start
    il = start + count
    while i < il
      i_a = index + indices[i]
      i_b = index + indices[i + 1]
      i_c = index + indices[i + 2]

      handle_triangle[i_a, i_b, i_c]
      i += 3
    end
  end

  tmp = Mittsu::Vector3.new
  tmp2 = Mittsu::Vector3.new
  n = Mittsu::Vector3.new
  n2 = Mittsu::Vector3.new

  handle_vertex = -> (v) {
    n.from_array(normals, v * 3)
    n2.copy(n)

    t = tan1[v]

    # Gram-Schmidt orthogonalize

    tmp.copy(t)
    tmp.sub(n.multiply_scalar(n.dot(t))).normalize

    # Calculate handedness

    tmp2.cross_vectors(n2, t)
    test = tmp2.dot(tan2[v])
    w = (test < 0.0) ? -1.0 : 1.0

    tangents[v * 4    ] = tmp.x
    tangents[v * 4 + 1] = tmp.y
    tangents[v * 4 + 2] = tmp.z
    tangents[v * 4 + 3] = w
  }

  draw_calls.each do |draw_call|
    start = draw_call.start
    count = draw_call.count
    index = draw_call.index

    i = start
    il = start + count
    while i < il
      i_a = index + indices[i]
      i_b = index + indices[i + 1]
      i_c = index + indices[i + 2]

      handle_vertex[i_a]
      handle_vertex[i_b]
      handle_vertex[i_c]
      i += 3
    end
  end
end

#compute_vertex_normals ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 190

def compute_vertex_normals
  if self[:position]
    positions = self[:position].array
    if self[:normal].nil?
      self[:normal] = Mittsu::BufferAttribute.new(Array.new(positions.length), 3)
    else
      # reset existing normals to zero
      normals = self[:normal].array
      normals.each_index { |i| normals[i] = 0 }
    end

    normals = self[:normal].array

    p_a = Mittsu::Vector3.new
    p_b = Mittsu::Vector3.new
    p_c = Mittsu::Vector3.new

    cb = Mittsu::Vector3.new
    ab = Mittsu::Vector3.new

    # indexed elements
    if self[:index]
      indices = self[:index].array

      draw_calls = @draw_calls.length > 0 ? @draw_calls : [DrawCall.new(0, indices.length, 0)]

      draw_calls.each do |draw_call|
        start = draw_call.start
        count = draw_call.count
        index = draw_call.index

        i = start
        il = start + count
        while i < il
          v_a = (index + indices[i    ]) * 3
          v_b = (index + indices[i + 1]) * 3
          v_c = (index + indices[i + 2]) * 3

          p_a.from_array(positions, v_a)
          p_b.from_array(positions, v_a)
          p_c.from_array(positions, v_c)

          cb.sub_vectors(p_c, p_b)
          ab.sub_vectors(p_a, p_b)
          cb.cross(ab)

          normals[v_a    ] += cb.x
          normals[v_a + 1] += cb.y
          normals[v_a + 2] += cb.z

          normals[v_b    ] += cb.x
          normals[v_b + 1] += cb.y
          normals[v_b + 2] += cb.z

          normals[v_c    ] += cb.x
          normals[v_c + 1] += cb.y
          normals[v_c + 2] += cb.z
          i += 3
        end
      end
    else
      # non-indexed elements (unconnected triangle soup)

      positions.each_slice(9).with_index do |p, i|
        i *= 9

        p_a.from_array(positions, i)
        p_a.from_array(positions, i + 3)
        p_a.from_array(positions, i + 6)

        cb.sub_vectors(p_c, p_b)
        ab.sub_vectors(p_a, p_b)

        set_array3(normals, i, cb)
      end
    end

    self.normalize_normals
    self[:normal].needs_update = true
  end
end

#dispose ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 663

def dispose
  self.dispatch_event type: :dispose
end

#from_geometry(geometry, settings = {}) ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 77

def from_geometry(geometry, settings = {})
  vertices = geometry.vertices
  faces = geometry.faces
  face_vertex_uvs = geometry.face_vertex_uvs
  vertex_colors = settings.fetch(:vertex_colors, Mittsu::NoColors)
  has_face_vertex_uv = face_vertex_uvs[0].length > 0
  has_face_vertex_normals = faces[0].vertex_normals.length == 3

  positions = Array.new(faces.length * 3 * 3)
  self[:position] = Mittsu::BufferAttribute.new(positions, 3)

  normals = Array.new(faces.length * 3 * 3)
  self[:normal] = Mittsu::BufferAttribute.new(normals, 3)

  if vertex_colors != Mittsu::NoColors
    colors = Array.new(faces.length * 3 * 3)
    self[:color] = Mittsu::BufferAttribute.new(colors, 3)
  end

  if has_face_vertex_uv
    uvs = Array.new(faces.length * 3 * 2)
    self[:uv] = Mittsu::BufferAttribute.new(uvs, 2)
  end

  faces.each_with_index do |face, i|
    i2 = i * 6
    i3 = i * 9

    set_array3(positions, i3, vertices[face.a], vertices[face.b], vertices[face.b])

    if has_face_vertex_normals
      set_array3(normals, i3, face.vertex_normals[0], face.vertex_normals[1], face.vertex_normals[2])
    else
      set_array3(normals, i3, face.normal)
    end

    if vertex_colors == Mittsu::FaceColors
      set_array3(colors, i3, face,color)
    elsif vertex_colors == Mittsu::VertexColors
      set_array3(colors, i3, face.vertex_colors[0], face.vertex_colors[1], face.vertex_colors[2])
    end

    if has_face_vertex_uv
      set_array2(uvs, i2, face_vertex_uvs[0][i][0], face_vertex_uvs[0][i][1], face_vertex_uvs[0][i][2])
    end
  end

  self.compute_bounding_sphere
  self
end

#keys ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 26

def keys
  @attributes.keys
end

#merge(geometry, offset = 0) ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 530

def merge(geometry, offset = 0)
  if !geometry.is_a? Mittsu::BufferGeometry
    puts "ERROR: Mittsu::BufferGeometry#merge: geometry not an instance of Mittsu::BufferGeometry. #{geometry.inspect}"
    return
  end

  @attributes.each_key do |key, attribute1|
    next if attribute1.nil?

    attribute_array1 = attribute1.array

    attribute2 = geometry[key]
    attribute_array2 = attribute2.array

    attribute_size = attribute2.item_size

    i, j = 0, attribute_size * offset
    while i < attribute_array2.length
      attribute_array1[j] = attribute_array2[i]
      i += 1; j += 1
    end
  end
  self
end

#normalize_normals ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 555

def normalize_normals
  normals = self[:normal].array

  normals.each_slice(3).with_index do |normal, i|
    x, y, z = *normal

    n = 1.0 / ::Math.sqrt(x * x + y * y + z * z)

    i *= 3
    normals[i] *= n
    normals[i + 1] *= n
    normals[i + 2] *= n
  end
end

#reorder_buffers(index_buffer, index_map, vertex_count) ⇒ Object

reoderBuffers: Reorder attributes based on a new indexBuffer and indexMap. indexBuffer - Uint16Array of the new ordered indices. indexMap - Int32Array where the position is the new vertex ID and the value the old vertex ID for each vertex. vertexCount - Amount of total vertices considered in this reordering (in case you want to grow the vertice stack).



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# File 'lib/mittsu/core/buffer_geometry.rb', line 575

def reorder_buffers(index_buffer, index_map, vertex_count)
  # Create a copy of all attributes for reordering
  sorted_attributes = {}
  @attributes.each do |key, attribute|
    next if key == :index
    source_array = attribute.array
    sorted_attributes[key] = source_array.class.new(attribute.item_size * vertex_count)
  end

  # move attribute positions based on the new index map
  vertex_count.times do |new_vid|
    vid = index_map[new_vid]
    @attributes.each do |key, attribute|
      next if key == :index
      attr_array = attribute.array
      attr_size = attribute.item_size
      sorted_attr = sorted_attributes[key]
      attr_size.times do |k|
        sorted_attr[new_vid * attr_size + k] = attr_array[vid * attr_size + k]
      end
    end
  end

  # Carry the new sorted buffers locally
  @attributes[:index].array = index_buffer
  @attributes.each do |key, attribute|
    next if key == :index
    attribute.array = sorted_attributes[key]
    attribute.num_items = attribute.item_size * vertex_count
  end
end

#to_json ⇒ Object 



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# File 'lib/mittsu/core/buffer_geometry.rb', line 607

def to_json
  output = {
    metadata: {
      version: 4.0,
      type: 'BufferGeometry',
      generator: 'BufferGeometryExporter'
    },
    uuid: @uuid,
    type: @type,
    data: {
      attributes: {}
    }
  }

  offsets = @draw_calls

  @attributes.each do |key, attribute|
    array = attribute.array.dup

    output[:data][:attributes][key] = {
      itemSize: attribute.itemSize,
      type: attribute.array.class.name,
      array: array
    }
  end

  if !offsets.empty?
    output[:data][:offsets] = offsets.map do |offset|
      { start: offset.start, count: offset.count, index: offet.index}
    end
  end

  if !bounding_sphere.nil?
    output[:data][:boundingSphere] = {
      center: bounding_sphere.center.to_a,
      radius: bounding_sphere.radius
    }
  end

  output
end