Bump version

README.md

@@ -1,8 +1,13 @@
 # CyberarmEngine
 
-Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file `lib/cyberarm_engine`. To experiment with that code, run `bin/console` for an interactive prompt.
+Yet Another Game Engine On Top Of Gosu
 
-TODO: Delete this and the text above, and describe your gem
+## Features
+* [Shoes-like](http://shoesrb.com) GUI support
+* OpenGL Shader support (requires [opengl-bindings](https://github.com/vaiorabbit/ruby-opengl) gem)
+* Includes classes for handling Vectors, Rays, Bounding Boxes, and Transforms
+* GameState system
+* Monolithic GameObjects
 
 ## Installation
 
@@ -22,7 +27,32 @@ Or install it yourself as:
 
 ## Usage
 
-TODO: Write usage instructions here
+```ruby
+require "cyberarm_engine"
+
+class Hello < CyberarmEngine::GuiState
+  def setup
+    stack do
+      label "Hello World!"
+
+      button "close" do
+        window.close
+      end
+    end
+  end
+end
+
+class Window < CyberarmEngine::Engine
+  def initialize
+    super
+    self.show_cursor = true
+
+    push_state(Hello)
+  end
+end
+
+Window.new.show
+```
 
 ## Development
 

cyberarm_engine.gemspec

@@ -28,7 +28,7 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_dependency "gosu", "~> 0.14.0"
+  spec.add_dependency "gosu", "~> 0.15.0"
 
   spec.add_development_dependency "bundler", "~> 1.16"
   spec.add_development_dependency "rake", "~> 10.0"

lib/cyberarm_engine.rb

@@ -4,6 +4,7 @@ rescue LoadError => e
   pp e
   require "gosu"
 end
+require "json"
 
 require_relative "cyberarm_engine/version"
 
@@ -20,9 +21,13 @@ require_relative "cyberarm_engine/transform"
 require_relative "cyberarm_engine/ray"
 require_relative "cyberarm_engine/shader" if defined?(OpenGL)
 require_relative "cyberarm_engine/background"
+require_relative "cyberarm_engine/animator"
 
 require_relative "cyberarm_engine/text"
 require_relative "cyberarm_engine/timer"
+require_relative "cyberarm_engine/config_file"
+
+require_relative "cyberarm_engine/ui/dsl"
 
 require_relative "cyberarm_engine/ui/theme"
 require_relative "cyberarm_engine/ui/event"
@@ -40,7 +45,5 @@ require_relative "cyberarm_engine/ui/elements/stack"
 require_relative "cyberarm_engine/ui/elements/check_box"
 require_relative "cyberarm_engine/ui/elements/progress"
 
-require_relative "cyberarm_engine/ui/dsl"
-
 require_relative "cyberarm_engine/game_state"
 require_relative "cyberarm_engine/ui/gui_state"

lib/cyberarm_engine/animator.rb

@@ -0,0 +1,54 @@
+module CyberarmEngine
+  class Animator
+    DEFAULT_TWEEN = :linear
+    def initialize(start_time:, duration:, from:, to:, &block)
+      @start_time, @duration = start_time, duration
+      @from, @to = from.dup, to.dup
+      @block = block
+    end
+
+    def update
+      @block.call(self, @from, @to) if @block
+    end
+
+    def progress
+      (@start_time.to_f + (Gosu.milliseconds - @start_time)) / (@start_time + @duration.to_f)
+    end
+
+    def complete?
+      progress >= 1.0
+    end
+
+    def transition(from, to, tween = DEFAULT_TWEEN)
+      from + (to - from) * send("tween_#{tween}", progress)
+    end
+
+    def color_transition(from, to, tween = DEFAULT_TWEEN)
+      r = transition(from.red, to.red)
+      g = transition(from.green, to.green)
+      b = transition(from.blue, to.blue)
+      a = transition(from.alpha, to.alpha)
+
+      Gosu::Color.rgba(r, g, b, a)
+    end
+
+    def color_hsv_transition(from, to, tween = DEFAULT_TWEEN)
+      hue = transition(from.hue, to.hue, tween)
+      saturation = transition(from.saturation, to.saturation, tween)
+      value = transition(from.value, to.value, tween)
+      alpha = transition(from.alpha, to.alpha, tween)
+
+      Gosu::Color.from_ahsv(alpha, hue, saturation, value)
+    end
+
+    # NOTE: Use this for future reference? https://github.com/danro/easing-js/blob/master/easing.js
+
+    def tween_linear(t)
+      t
+    end
+
+    def tween_sine(t)
+      Math.sin(t) * t
+    end
+  end
+end

lib/cyberarm_engine/config_file.rb

@@ -0,0 +1,46 @@
+module CyberarmEngine
+  class ConfigFile
+    def initialize(file:)
+      @file = file
+
+      if File.exist?(@file)
+        deserialize
+      else
+        @data = {}
+      end
+    end
+
+    def []= *keys, value
+      last_key = keys.last
+
+      if keys.size == 1
+        hash = @data
+      else
+        keys.pop
+        hash = @data[keys.shift] ||= {}
+
+        keys.each do |key|
+          hash[key] ||= {}
+        end
+      end
+
+      hash[last_key] = value
+    end
+
+    def get(*keys)
+      @data.dig(*keys)
+    end
+
+    def serialize
+      JSON.dump(@data)
+    end
+
+    def deserialize
+      @data = JSON.parse(File.read(@file), symbolize_names: true)
+    end
+
+    def save!
+      File.open(@file, "w") { |f| f.write(serialize) }
+    end
+  end
+end

lib/cyberarm_engine/game_state.rb

@@ -3,7 +3,7 @@ module CyberarmEngine
     include Common
 
     attr_accessor :options, :global_pause
-    attr_reader :game_objects, :containers
+    attr_reader :game_objects
 
     def initialize(options={})
       @options = options

lib/cyberarm_engine/shader.rb

@@ -2,12 +2,44 @@ module CyberarmEngine
   # Ref: https://github.com/vaiorabbit/ruby-opengl/blob/master/sample/OrangeBook/brick.rb
   class Shader
     include OpenGL
-    @@shaders = {}
+    @@shaders = {} # Cache for {Shader} instances
+    PREPROCESSOR_CHARACTER = "@".freeze # magic character for preprocessor phase of {Shader} compilation
 
+    # add instance of {Shader} to cache
+    #
+    # @param name [String]
+    # @param instance [Shader]
     def self.add(name, instance)
       @@shaders[name] = instance
     end
 
+    # removes {Shader} from cache and cleans up
+    #
+    # @param name [String]
+    def self.delete(name)
+      shader = @@shaders.dig(name)
+
+      if shader
+        @@shaders.delete(name)
+
+        if shader.compiled?
+          glDeleteProgram(shader.program)
+        end
+      end
+    end
+
+    ##
+    # runs _block_ using {Shader} with _name_
+    #
+    # @example
+    #
+    #   CyberarmEngine::Shader.use("blur") do |shader|
+    #     shader.uniform_float("radius", 20.0)
+    #     # OpenGL Code that uses shader
+    #   end
+    #
+    # @param name [String] name of {Shader} to use
+    # @return [void]
     def self.use(name, &block)
       shader = @@shaders.dig(name)
       if shader
@@ -17,22 +49,37 @@ module CyberarmEngine
       end
     end
 
+    # returns whether {Shader} with _name_ is in cache
+    #
+    # @param name [String]
+    # @return [Boolean]
     def self.available?(name)
       @@shaders.dig(name).is_a?(Shader)
     end
 
+    # returns instance of {Shader}, if it exists
+    #
+    # @param name [String]
+    # @return [Shader?]
     def self.get(name)
       @@shaders.dig(name)
     end
 
+    # returns currently active {Shader}, if one is active
+    #
+    # @return [Shader?]
     def self.active_shader
       @active_shader
     end
 
+    # sets currently active {Shader}
+    #
+    # @param instance [Shader] instance of {Shader} to set as active
     def self.active_shader=(instance)
       @active_shader = instance
     end
 
+    # stops using currently active {Shader}
     def self.stop
       shader = Shader.active_shader
 
@@ -43,96 +90,175 @@ module CyberarmEngine
       end
     end
 
+    # returns location of OpenGL Shader uniform
+    #
+    # @param variable [String]
     def self.attribute_location(variable)
       raise RuntimeError, "No active shader!" unless Shader.active_shader
       Shader.active_shader.attribute_location(variable)
     end
 
+    # sets _variable_ to _value_
+    #
+    # @param variable [String]
+    # @param value
     def self.set_uniform(variable, value)
       raise RuntimeError, "No active shader!" unless Shader.active_shader
       Shader.active_shader.set_uniform(variable, value)
     end
 
     attr_reader :name, :program
-    def initialize(name:, vertex: "shaders/default.vert", fragment:)
+    def initialize(name:, includes_dir: nil, vertex: "shaders/default.vert", fragment:)
+      raise "Shader name can not be blank" if name.length == 0
+
       @name = name
-      @vertex_file   = vertex
-      @fragment_file = fragment
+      @includes_dir = includes_dir
       @compiled = false
 
       @program = nil
 
-      @error_buffer_size = 1024
+      @error_buffer_size = 1024 * 8
       @variable_missing = {}
 
-      raise ArgumentError, "Shader files not found: #{@vertex_file} or #{@fragment_file}" unless shader_files_exist?
+      @data = {shaders: {}}
 
-      create_shaders
-      compile_shaders
+      unless shader_files_exist?(vertex: vertex, fragment: fragment)
+        raise ArgumentError, "Shader files not found: #{vertex} or #{fragment}"
+      end
+
+      create_shader(type: :vertex, source: File.read(vertex))
+      create_shader(type: :fragment, source: File.read(fragment))
+
+      compile_shader(type: :vertex)
+      compile_shader(type: :fragment)
+      link_shaders
+
+      @data[:shaders].each { |key, id| glDeleteShader(id) }
 
       # Only add shader if it successfully compiles
       if @compiled
+        puts "compiled!"
+        puts "Compiled shader: #{@name}"
         Shader.add(@name, self)
       else
-        puts "FAILED to compile shader: #{@name}", ""
+        glDeleteProgram(@program)
+        warn "FAILED to compile shader: #{@name}", ""
       end
     end
 
-    def shader_files_exist?
-      File.exist?(@vertex_file) && File.exist?(@fragment_file)
+    # whether vertex and fragment files exist on disk
+    #
+    # @return [Boolean]
+    def shader_files_exist?(vertex:, fragment:)
+      File.exist?(vertex) && File.exist?(fragment)
     end
 
-    def create_shaders
-      @vertex   = glCreateShader(GL_VERTEX_SHADER)
-      @fragment = glCreateShader(GL_FRAGMENT_SHADER)
+    # creates an OpenGL Shader of _type_ using _source_
+    #
+    # @param type [Symbol] valid values are: :vertex, :fragment
+    # @param source [String] source code for shader
+    def create_shader(type:, source:)
+      _shader = nil
 
-      source = [File.read(@vertex_file)].pack('p')
-      size   = [File.size(@vertex_file)].pack('I')
-      glShaderSource(@vertex, 1, source, size)
+      case type
+      when :vertex
+        _shader = glCreateShader(GL_VERTEX_SHADER)
+      when :fragment
+        _shader = glCreateShader(GL_FRAGMENT_SHADER)
+      else
+        raise ArgumentError, "Unsupported shader type: #{type.inspect}"
+      end
 
-      source = [File.read(@fragment_file)].pack('p')
-      size   = [File.size(@fragment_file)].pack('I')
-      glShaderSource(@fragment, 1, source, size)
+      processed_source = preprocess_source(source: source)
+
+      _source = [processed_source].pack("p")
+      _size = [processed_source.length].pack("I")
+      glShaderSource(_shader, 1, _source, _size)
+
+      @data[:shaders][type] =_shader
     end
 
-    def compile_shaders
-      return unless shader_files_exist?
+    # evaluates shader preprocessors
+    #
+    # currently supported preprocessors:
+    #
+    #   @include "file/path" "another/file/path" # => Replace line with contents of file; Shader includes_dir must be specified in constructor
+    #
+    # @example
+    #   # Example Vertex Shader #
+    #   # #version 330 core
+    #   # @include "material_struct"
+    #   # void main() {
+    #   #   gl_Position = vec4(1, 1, 1, 1);
+    #   # }
+    #
+    #   Shader.new(name: "model_renderer", includes_dir: "path/to/includes", vertex: "path/to/vertex_shader.glsl")
+    #
+    # @param source shader source code
+    def preprocess_source(source:)
+      lines = source.lines
 
-      glCompileShader(@vertex)
+      lines.each_with_index do |line, i|
+        if line.start_with?(PREPROCESSOR_CHARACTER)
+          preprocessor = line.strip.split(" ")
+          lines.delete(line)
+
+          case preprocessor.first
+          when "@include"
+            raise ArgumentError, "Shader preprocessor include directory was not given for shader #{@name}" unless @includes_dir
+
+            preprocessor[1..preprocessor.length - 1].join.scan(/"([^"]*)"/).flatten.each do |file|
+              source = File.read("#{@includes_dir}/#{file}.glsl")
+
+              lines.insert(i, source)
+            end
+          else
+            warn "Unsupported preprocessor #{preprocessor.first} for #{@name}"
+          end
+        end
+      end
+
+      lines.join
+    end
+
+    # compile OpenGL Shader of _type_
+    #
+    # @return [Boolean] whether compilation succeeded
+    def compile_shader(type:)
+      _compiled = false
+      _shader = @data[:shaders][type]
+      raise ArgumentError, "No shader for #{type.inspect}" unless _shader
+
+      glCompileShader(_shader)
       buffer = '    '
-      glGetShaderiv(@vertex, GL_COMPILE_STATUS, buffer)
+      glGetShaderiv(_shader, GL_COMPILE_STATUS, buffer)
       compiled = buffer.unpack('L')[0]
 
       if compiled == 0
         log = ' ' * @error_buffer_size
-        glGetShaderInfoLog(@vertex, @error_buffer_size, nil, log)
+        glGetShaderInfoLog(_shader, @error_buffer_size, nil, log)
         puts "Shader Error: Program \"#{@name}\""
-        puts "  Vectex Shader InfoLog:", "  #{log.strip.split("\n").join("\n  ")}\n\n"
+        puts "  #{type.to_s.capitalize} Shader InfoLog:", "  #{log.strip.split("\n").join("\n  ")}\n\n"
         puts "  Shader Compiled status: #{compiled}"
         puts "    NOTE: assignment of uniforms in shaders is illegal!"
         puts
-        return
+      else
+        _compiled = true
       end
 
-      glCompileShader(@fragment)
-      buffer = '    '
-      glGetShaderiv(@fragment, GL_COMPILE_STATUS, buffer)
-      compiled = buffer.unpack('L')[0]
-
-      if compiled == 0
-        log = ' ' * @error_buffer_size
-        glGetShaderInfoLog(@fragment, @error_buffer_size, nil, log)
-        puts "Shader Error: Program \"#{@name}\""
-        puts "  Fragment Shader InfoLog:", "  #{log.strip.split("\n").join("\n  ")}\n\n"
-        puts "  Shader Compiled status: #{compiled}"
-        puts "    NOTE: assignment of uniforms in shader is illegal!"
-        puts
-        return
-      end
+      return _compiled
+    end
 
+    # link compiled OpenGL Shaders in to a OpenGL Program
+    #
+    # @note linking must succeed or shader cannot be used
+    #
+    # @return [Boolean] whether linking succeeded
+    def link_shaders
       @program = glCreateProgram
-      glAttachShader(@program, @vertex)
-      glAttachShader(@program, @fragment)
+      @data[:shaders].values.each do |_shader|
+        glAttachShader(@program, _shader)
+      end
       glLinkProgram(@program)
 
       buffer = '    '
@@ -149,7 +275,10 @@ module CyberarmEngine
       @compiled = linked == 0 ? false : true
     end
 
-    # Returns the location of a uniform variable
+    # Returns the location of a uniform _variable_
+    #
+    # @param variable [String]
+    # @return [Integer] location of uniform
     def variable(variable)
       loc = glGetUniformLocation(@program, variable)
       if (loc == -1)
@@ -159,6 +288,7 @@ module CyberarmEngine
       return loc
     end
 
+    # @see Shader.use Shader.use
     def use(&block)
       return unless compiled?
       raise "Another shader is already in use! #{Shader.active_shader.name.inspect}" if Shader.active_shader
@@ -172,34 +302,97 @@ module CyberarmEngine
       end
     end
 
+    # stop using shader, if shader is active
     def stop
       Shader.active_shader = nil if Shader.active_shader == self
       glUseProgram(0)
     end
 
+    # @return [Boolean] whether {Shader} successfully compiled
     def compiled?
       @compiled
     end
 
+    # returns location of a uniform _variable_
+    #
+    # @note Use {#variable} for friendly error handling
+    # @see #variable Shader#variable
+    #
+    # @param variable [String]
+    # @return [Integer]
     def attribute_location(variable)
       glGetUniformLocation(@program, variable)
     end
 
-    def set_uniform(variable, value, location = nil)
+    # send {Transform} to {Shader}
+    #
+    # @param variable [String]
+    # @param value [Transform]
+    # @param location [Integer]
+    # @return [void]
+    def uniform_transform(variable, value, location = nil)
       attr_loc = location ? location : attribute_location(variable)
 
-      case value.class.to_s.downcase.to_sym
-      when :integer
-        glUniform1i(attr_loc, value)
-      when :float
-        glUniform1f(attr_loc, value)
-      when :string
-      when :array
-      else
-        raise NotImplementedError, "Shader support for #{value.class.inspect} not implemented."
-      end
+      glUniformMatrix4fv(attr_loc, 1, GL_FALSE, value.to_gl.pack("F16"))
+    end
 
-      Window.handle_gl_error
+    # send Boolean to {Shader}
+    #
+    # @param variable [String]
+    # @param value [Boolean]
+    # @param location [Integer]
+    # @return [void]
+    def uniform_boolean(variable, value, location = nil)
+      attr_loc = location ? location : attribute_location(variable)
+
+      glUniform1i(attr_loc, value ? 1 : 0)
+    end
+
+    # send Integer to {Shader}
+    # @param variable [String]
+    # @param value [Integer]
+    # @param location [Integer]
+    # @return [void]
+    def uniform_integer(variable, value, location = nil)
+      attr_loc = location ? location : attribute_location(variable)
+
+      glUniform1i(attr_loc, value)
+    end
+
+    # send Float to {Shader}
+    #
+    # @param variable [String]
+    # @param value [Float]
+    # @param location [Integer]
+    # @return [void]
+    def uniform_float(variable, value, location = nil)
+      attr_loc = location ? location : attribute_location(variable)
+
+      glUniform1f(attr_loc, value)
+    end
+
+    # send {Vector} (x, y, z) to {Shader}
+    #
+    # @param variable [String]
+    # @param value [Vector]
+    # @param location [Integer]
+    # @return [void]
+    def uniform_vec3(variable, value, location = nil)
+      attr_loc = location ? location : attribute_location(variable)
+
+      glUniform3f(attr_loc, *value.to_a[0..2])
+    end
+
+    # send {Vector} to {Shader}
+    #
+    # @param variable [String]
+    # @param value [Vector]
+    # @param location [Integer]
+    # @return [void]
+    def uniform_vec4(variable, value, location = nil)
+      attr_loc = location ? location : attribute_location(variable)
+
+      glUniform4f(attr_loc, *value.to_a)
     end
   end
 end

lib/cyberarm_engine/transform.rb

@@ -1,12 +1,28 @@
 module CyberarmEngine
+  # Basic 4x4 matrix operations
   class Transform
     attr_reader :elements
     def initialize(matrix)
       @elements = matrix
 
       raise "Transform is wrong size! Got #{@elements.size}, expected 16" if 16 != @elements.size
+      raise "Invalid value for matrix, must all be numeric!" if @elements.any? { |e| e.nil? || !e.is_a?(Numeric)}
     end
 
+    def self.identity
+      Transform.new(
+        [
+          1, 0, 0, 0,
+          0, 1, 0, 0,
+          0, 0, 1, 0,
+          0, 0, 0, 1
+        ]
+      )
+    end
+
+    ### 2D Operations meant for interacting with Gosu ###
+
+    # 2d rotate operation, replicates Gosu's Gosu.rotate function
     def self.rotate(angle, rotate_around = nil)
       double c = Math.cos(angle).degrees_to_radians
       double s = Math.sin(angle).degrees_to_radians
@@ -31,6 +47,7 @@ module CyberarmEngine
       return rotate_matrix
     end
 
+    # 2d translate operation, replicates Gosu's Gosu.translate function
     def self.translate(vector)
       x, y, z = vector.to_a[0..2]
       matrix = [
@@ -43,6 +60,7 @@ module CyberarmEngine
       Transform.new(matrix)
     end
 
+    # 2d scale operation, replicates Gosu's Gosu.rotate function
     def self.scale(vector, center_around = nil)
       scale_x, scale_y, scale_z = vector.to_a[0..2]
       matrix = [
@@ -80,5 +98,176 @@ module CyberarmEngine
 
       Transform.new(matrix)
     end
+
+    #### 3D Operations meant for OpenGL ###
+
+    def self.translate_3d(vector)
+      x, y, z = vector.to_a[0..2]
+      matrix = [
+        1, 0, 0, x,
+        0, 1, 0, y,
+        0, 0, 1, z,
+        0, 0, 0, 1,
+      ]
+
+      Transform.new(matrix)
+    end
+
+    def self.rotate_3d(vector, order = "zyx")
+      x, y, z = vector.to_a[0..2].map { |axis| axis * Math::PI / 180.0 }
+
+      rotation_x = Transform.new(
+        [
+          1, 0,           0,            0,
+          0, Math.cos(x), -Math.sin(x), 0,
+          0, Math.sin(x), Math.cos(x),  0,
+          0, 0,           0,            1
+        ]
+      )
+
+      rotation_y = Transform.new(
+        [
+          Math.cos(y),  0, Math.sin(y), 0,
+          0,            1, 0,           0,
+          -Math.sin(y), 0, Math.cos(y), 0,
+          0,            0, 0,           1
+        ]
+      )
+
+      rotation_z = Transform.new(
+        [
+          Math.cos(z), -Math.sin(z), 0, 0,
+          Math.sin(z), Math.cos(z),  0, 0,
+          0,           0,            1, 0,
+          0,           0,            0, 1
+        ]
+      )
+
+      rotation_z * rotation_y * rotation_x
+    end
+
+    # Implements glRotatef
+    # https://www.khronos.org/registry/OpenGL-Refpages/gl2.1/xhtml/glRotate.xml
+    def self.rotate_gl(angle, axis)
+      radians = angle * Math::PI / 180.0
+      s = Math.sin(radians)
+      c = Math.cos(radians)
+
+      axis = axis.normalized
+      x, y, z = axis.to_a[0..2]
+
+      n = (1.0 - c)
+
+      Transform.new(
+        [
+          x * x * n + c,     x * y * n - z * s, x * z * n + y * s, 0,
+          y * x * n + z * s, y * y * n + c,     y * z * n - x * s, 0,
+          x * z * n - y * s, y * z * n + x * s, z * z * n + c,     0,
+          0,                 0,                 0,               1.0
+        ]
+      )
+    end
+
+    def self.scale_3d(vector)
+      x, y, z = vector.to_a[0..2]
+
+      Transform.new(
+        [
+          x, 0, 0, 0,
+          0, y, 0, 0,
+          0, 0, z, 0,
+          0, 0, 0, 1
+        ]
+      )
+    end
+
+    def self.perspective(fov_y, aspect_ratio, near, far)
+      f = 1.0 / Math.tan(fov_y.degrees_to_radians / 2.0) # cotangent
+      zn = (far + near.to_f) / (near - far.to_f)
+      zf = (2.0 * far * near.to_f) / (near - far.to_f)
+
+      Transform.new(
+        [
+          f / aspect_ratio, 0.0,    0.0, 0.0,
+          0.0,                f,    0.0, 0.0,
+          0.0,                0.0,   zn, zf,
+          0.0,                0.0, -1.0, 0.0
+        ]
+      )
+    end
+
+    def self.view(eye, orientation)
+      # https://www.3dgep.com/understanding-the-view-matrix/#The_View_Matrix
+      cosPitch = Math.cos(orientation.z * Math::PI / 180.0)
+      sinPitch = Math.sin(orientation.z * Math::PI / 180.0)
+      cosYaw = Math.cos(orientation.y * Math::PI / 180.0)
+      sinYaw = Math.sin(orientation.y * Math::PI / 180.0)
+
+      x_axis = Vector.new(cosYaw, 0, -sinYaw)
+      y_axis = Vector.new(sinYaw * sinPitch, cosPitch, cosYaw * sinPitch)
+      z_axis = Vector.new(sinYaw * cosPitch, -sinPitch, cosPitch * cosYaw)
+
+      Transform.new(
+        [
+                  x_axis.x,         y_axis.y,         z_axis.z, 0,
+                  x_axis.x,         y_axis.y,         z_axis.z, 0,
+                  x_axis.x,         y_axis.y,         z_axis.z, 0,
+          -x_axis.dot(eye), -y_axis.dot(eye), -z_axis.dot(eye), 1
+        ]
+      )
+    end
+
+    def *(other)
+
+      case other
+      when CyberarmEngine::Vector
+        matrix = @elements.clone
+        list = other.to_a
+
+        @elements.each_with_index do |e, i|
+          matrix[i] = e + list[i % 4]
+        end
+
+        Transform.new(matrix)
+
+      when CyberarmEngine::Transform
+        return multiply_matrices(other)
+      else
+        p other.class
+        raise TypeError, "Expected CyberarmEngine::Vector or CyberarmEngine::Transform got #{other.class}"
+      end
+    end
+
+    def get(x, y)
+      width = 4
+
+      # puts "Transform|#{self.object_id} -> #{@elements[width * y + x].inspect} (index: #{width * y + x})"
+      @elements[width * y + x]
+    end
+
+    def multiply_matrices(other)
+      matrix = Array.new(16, 0)
+
+      4.times do |x|
+        4.times do |y|
+          4.times do |k|
+            matrix[4 * y + x] += get(x, k) * other.get(k, y)
+          end
+        end
+      end
+
+      return Transform.new(matrix)
+    end
+
+    # arranges Matrix in column major form
+    def to_gl
+      e = @elements
+      [
+        e[0], e[4], e[8],  e[12],
+        e[1], e[5], e[9],  e[13],
+        e[2], e[6], e[10], e[14],
+        e[3], e[7], e[11], e[15]
+      ]
+    end
   end
 end

lib/cyberarm_engine/ui/dsl.rb

@@ -1,102 +1,99 @@
 module CyberarmEngine
   module DSL
     def flow(options = {}, &block)
-      options[:parent] = @containers.last
-      options[:theme] = current_theme
-      _container = Element::Flow.new(options, block)
-      @containers << _container
-      _container.build
-      _container.parent.add(_container)
-      @containers.pop
-
-      return _container
+      container(CyberarmEngine::Element::Flow, options, &block)
     end
 
     def stack(options = {}, &block)
-      options[:parent] = @containers.last
-      options[:theme] = current_theme
-      _container = Element::Stack.new(options, block)
-      @containers << _container
-      _container.build
-      _container.parent.add(_container)
-      @containers.pop
-
-      return _container
+      container(CyberarmEngine::Element::Stack, options, &block)
     end
 
     def label(text, options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::Label.new(text, options, block)
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::Label.new(text, options, block) )
     end
 
     def button(text, options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::Button.new(text, options, block) { if block.is_a?(Proc); block.call; end }
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::Button.new(text, options, block) { if block.is_a?(Proc); block.call; end } )
     end
 
     def edit_line(text, options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::EditLine.new(text, options, block)
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::EditLine.new(text, options, block) )
     end
 
     def toggle_button(options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::ToggleButton.new(options, block)
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::ToggleButton.new(options, block) )
     end
 
     def check_box(text, options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::CheckBox.new(text, options, block)
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::CheckBox.new(text, options, block) )
     end
 
     def image(path, options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::Image.new(path, options, block)
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::Image.new(path, options, block) )
     end
 
     def progress(options = {}, &block)
-      options[:parent] = @containers.last
+      options[:parent] = element_parent
       options[:theme] = current_theme
-      _element = Element::Progress.new(options, block)
-      @containers.last.add(_element)
 
-      return _element
+      add_element( Element::Progress.new(options, block) )
     end
 
     def background(color = Gosu::Color::NONE)
-      @containers.last.style.background = color
+      element_parent.style.background = color
     end
 
     def theme(theme)
-      @containers.last.options[:theme] = theme
+      element_parent.options[:theme] = theme
     end
 
     def current_theme
-      @containers.last.options[:theme]
+      element_parent.options[:theme]
+    end
+
+    private def add_element(element)
+      element_parent.add(element)
+
+      return element
+    end
+
+    private def element_parent
+      $__current_container__
+    end
+
+    private def container(klass, options = {}, &block)
+      options[:parent] = element_parent
+      options[:theme] = current_theme
+
+      _container = klass.new(options, block)
+
+      old_parent = element_parent
+      $__current_container__ = _container
+
+      _container.build
+      _container.parent.add(_container)
+
+      $__current_container__ = old_parent
+
+      return _container
     end
   end
 end

lib/cyberarm_engine/ui/element.rb

@@ -168,6 +168,14 @@ module CyberarmEngine
       end
     end
 
+    def content_width
+      @width
+    end
+
+    def noncontent_width
+      (inner_width + outer_width) - width
+    end
+
     def outer_width
       @style.margin_left + width + @style.margin_right
     end
@@ -184,6 +192,14 @@ module CyberarmEngine
       end
     end
 
+    def content_height
+      @height
+    end
+
+    def noncontent_height
+      (inner_height + outer_height) - height
+    end
+
     def outer_height
       @style.margin_top + height + @style.margin_bottom
     end
@@ -196,7 +212,7 @@ module CyberarmEngine
       raise "dimension must be either :width or :height" unless dimension == :width || dimension == :height
       if size && size.is_a?(Numeric)
         if size.between?(0.0, 1.0)
-          @parent.send(:"#{dimension}") * size
+          ((@parent.send(:"content_#{dimension}") - self.send(:"noncontent_#{dimension}") - 1) * size).round
         else
           size
         end

lib/cyberarm_engine/ui/elements/container.rb

@@ -31,6 +31,20 @@ module CyberarmEngine
         recalculate
       end
 
+      def clear(&block)
+        @children.clear
+
+        old_container = $__current_container__
+
+        $__current_container__ = self
+        block.call(self) if block
+
+        $__current_container__ = old_container
+
+        recalculate
+        root.gui_state.request_recalculate
+      end
+
       def render
         Gosu.clip_to(@x, @y, width, height) do
           @children.each(&:draw)

lib/cyberarm_engine/ui/elements/edit_line.rb

@@ -16,16 +16,31 @@ module CyberarmEngine
         @text_input = Gosu::TextInput.new
         @text_input.text = text
 
+        @offset_x = 0
+
         return self
       end
 
       def render
         Gosu.clip_to(@text.x, @text.y, @style.width, @text.height) do
-          draw_text
-          Gosu.draw_rect(caret_position, @text.y, @caret_width, @caret_height, @caret_color, @z + 40) if @focus && @show_caret
+          Gosu.translate(-@offset_x, 0) do
+            draw_selection
+            draw_caret if @focus && @show_caret
+            draw_text
+          end
         end
       end
 
+      def draw_caret
+        Gosu.draw_rect(caret_position, @text.y, @caret_width, @caret_height, @caret_color, @z)
+      end
+
+      def draw_selection
+        selection_width = caret_position - selection_start_position
+
+        Gosu.draw_rect(selection_start_position, @text.y, selection_width, @text.height, default(:selection_color), @z)
+      end
+
       def update
         if @type == :password
           @text.text = default(:password_character) * @text_input.text.length
@@ -38,6 +53,51 @@ module CyberarmEngine
 
           @show_caret = !@show_caret
         end
+
+        keep_caret_visible
+      end
+
+      def move_caret_to_mouse(mouse_x)
+        1.upto(@text.text.length) do |i|
+          if mouse_x < @text.x + @text.textobject.text_width(@text.text[0...i])
+            @text_input.caret_pos = @text_input.selection_start = i - 1;
+            return
+          end
+        end
+
+        @text_input.caret_pos = @text_input.selection_start = @text_input.text.length
+      end
+
+      def keep_caret_visible
+        caret_pos = (caret_position - @text.x) + @caret_width
+
+        @last_text ||= "/\\"
+        @last_pos ||= -1
+
+        puts "caret pos: #{caret_pos}, width: #{@width}, offset: #{@offset_x}" if (@last_text != @text.text) || (@last_pos != caret_pos)
+
+        @last_text = @text.text
+        @last_pos = caret_pos
+
+
+        if caret_pos.between?(@offset_x, @width + @offset_x)
+          # Do nothing
+
+        elsif caret_pos < @offset_x
+          if caret_pos > @width
+            @offset_x = caret_pos + @width
+          else
+            @offset_x = 0
+          end
+
+        elsif caret_pos > @width
+          @offset_x = caret_pos - @width
+          puts "triggered"
+
+        else
+          # Reset to Zero
+          @offset_x = 0
+        end
       end
 
       def left_mouse_button(sender, x, y)
@@ -47,6 +107,8 @@ module CyberarmEngine
         @caret_last_interval = Gosu.milliseconds
         @show_caret = true
 
+        move_caret_to_mouse(x)
+
         return :handled
       end
 
@@ -79,12 +141,19 @@ module CyberarmEngine
         return :handled
       end
 
-      # TODO: Fix caret rendering in wrong position unless caret_pos is at end of text
       def caret_position
+        text_input_position_for(:caret_pos)
+      end
+
+      def selection_start_position
+        text_input_position_for(:selection_start)
+      end
+
+      def text_input_position_for(method)
         if @type == :password
-          @text.x + @text.textobject.text_width(default(:password_character) * @text_input.text[0..@text_input.caret_pos-1].length)
+          @text.x + @text.textobject.text_width(default(:password_character) * @text_input.text[0..@text_input.send(method)].length)
         else
-          @text.x + @text.textobject.text_width(@text_input.text[0..@text_input.caret_pos-1])
+          @text.x + @text.textobject.text_width(@text_input.text[0..@text_input.send(method)])
         end
       end
 

lib/cyberarm_engine/ui/event.rb

@@ -23,6 +23,7 @@ module CyberarmEngine
         return :handled if handler.call(self, *args) == :handled
       end
 
+      parent.publish(event, *args) if parent
       return nil
     end
 

lib/cyberarm_engine/ui/gui_state.rb

@@ -12,7 +12,7 @@ module CyberarmEngine
 
       @root_container = Element::Stack.new(gui_state: self)
       @game_objects << @root_container
-      @containers     = [@root_container]
+      $__current_container__ = @root_container
 
       @active_width  = window.width
       @active_height = window.height

lib/cyberarm_engine/ui/theme.rb

@@ -88,6 +88,7 @@ module CyberarmEngine
         caret_width: 2,
         caret_color: Gosu::Color::WHITE,
         caret_interval: 500,
+        selection_color: Gosu::Color::GREEN,
       },
 
       Image: { # < Element
@@ -111,7 +112,7 @@ module CyberarmEngine
         height: 36,
         background: 0xff111111,
         fraction_background: [0xffc75e61, 0xffe26623],
-        border_thickness: 4,
+        border_thickness: 1,
         border_color: [0xffd59674, 0xffff8746]
       }
     }.freeze

lib/cyberarm_engine/vector.rb

@@ -1,25 +1,61 @@
 module CyberarmEngine
   class Vector
+    ##
+    # Creates a up vector
+    #
+    #   Vector.new(0, 1, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.up
       Vector.new(0, 1, 0)
     end
 
+    ##
+    # Creates a down vector
+    #
+    #   Vector.new(0, -1, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.down
       Vector.new(0, -1, 0)
     end
 
+    ##
+    # Creates a left vector
+    #
+    #   Vector.new(-1, 0, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.left
       Vector.new(-1, 0, 0)
     end
 
+    ##
+    # Creates a right vector
+    #
+    #   Vector.new(1, 0, 0)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.right
       Vector.new(1, 0, 0)
     end
 
+    ##
+    # Creates a forward vector
+    #
+    #   Vector.new(0, 0, 1)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.forward
       Vector.new(0, 0, 1)
     end
 
+    ##
+    # Creates a backward vector
+    #
+    #   Vector.new(0, 0, -1)
+    #
+    # @return [CyberarmEngine::Vector]
     def self.backward
       Vector.new(0, 0, -1)
     end
@@ -43,21 +79,30 @@ module CyberarmEngine
     alias w weight
     alias w= weight=
 
+    # @return [Boolean]
     def ==(other)
       if other.is_a?(Numeric)
         @x      == other &&
         @y      == other &&
         @z      == other &&
         @weight == other
-      else
+      elsif other.is_a?(Vector)
         @x      == other.x &&
         @y      == other.y &&
         @z      == other.z &&
         @weight == other.weight
+      else
+        other == self
       end
     end
 
-    # Performs math operation, excluding @weight
+    # Create a new vector using {x} and {y} values
+    # @return [CyberarmEngine::Vector]
+    def xy
+      Vector.new(@x, @y)
+    end
+
+    # Performs math operation, excluding {weight}
     private def operator(function, other)
       if other.is_a?(Numeric)
         Vector.new(
@@ -74,22 +119,26 @@ module CyberarmEngine
       end
     end
 
-    # Adds Vector and Numberic or Vector and Vector, excluding @weight
+    # Adds Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def +(other)
       operator("+", other)
     end
 
-    # Subtracts Vector and Numberic or Vector and Vector, excluding @weight
+    # Subtracts Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def -(other)
       operator("-", other)
     end
 
-    # Multiplies Vector and Numberic or Vector and Vector, excluding @weight
+    # Multiplies Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def *(other)
       operator("*", other)
     end
 
-    # Divides Vector and Numberic or Vector and Vector, excluding @weight
+    # Divides Vector and Numeric or Vector and Vector, excluding {weight}
+    # @return [CyberarmEngine::Vector]
     def /(other)
       # Duplicated to protect from DivideByZero
       if other.is_a?(Numeric)
@@ -107,6 +156,8 @@ module CyberarmEngine
       end
     end
 
+    # dot product of {Vector}
+    # @return [Integer|Float]
     def dot(other)
       product = 0
 
@@ -120,6 +171,8 @@ module CyberarmEngine
       return product
     end
 
+    # cross product of {Vector}
+    # @return [CyberarmEngine::Vector]
     def cross(other)
       a = self.to_a
       b = other.to_a
@@ -132,24 +185,40 @@ module CyberarmEngine
     end
 
     # returns degrees
+    # @return [Float]
     def angle(other)
       Math.acos( self.normalized.dot(other.normalized) ) * 180 / Math::PI
     end
 
     # returns magnitude of Vector, ignoring #weight
+    # @return [Float]
     def magnitude
       Math.sqrt((@x * @x) + (@y * @y) + (@z * @z))
     end
 
+    ##
+    # returns normalized {Vector}
+    #
+    # @example
+    #   CyberarmEngine::Vector.new(50, 21.2, 45).normalized
+    #   # => <CyberarmEngine::Vector:0x001 @x=0.7089... @y=0.3005... @z=0.6380... @weight=0>
+    #
+    # @return [CyberarmEngine::Vector]
     def normalized
       mag = magnitude
       self / Vector.new(mag, mag, mag)
     end
 
+
+    # returns a direction {Vector}
+    #
+    # z is pitch
+    #
+    # y is yaw
+    #
+    # x is roll
+    # @return [CyberarmEngine::Vector]
     def direction
-      # z is pitch
-      # y is yaw
-      # x is roll
       _x = -Math.sin(@y.degrees_to_radians) * Math.cos(@z.degrees_to_radians)
       _y = Math.sin(@z.degrees_to_radians)
       _z = Math.cos(@y.degrees_to_radians) * Math.cos(@z.degrees_to_radians)
@@ -157,41 +226,63 @@ module CyberarmEngine
       Vector.new(_x, _y, _z)
     end
 
+    # returns an inverse {Vector}
+    # @return [CyberarmEngine::Vector]
     def inverse
       Vector.new(1.0 / @x, 1.0 / @y, 1.0 / @z)
     end
 
+    # Adds up values of {x}, {y}, and {z}
+    # @return [Integer|Float]
     def sum
       @x + @y + @z
     end
 
+    ##
+    # Linear interpolation: smoothly transition between two {Vector}
+    #
+    #   CyberarmEngine::Vector.new(100, 100, 100).lerp( CyberarmEngine::Vector.new(0, 0, 0), 0.75 )
+    #   # => <CyberarmEngine::Vector:0x0001 @x=75.0, @y=75.0, @z=75.0, @weight=0>
+    #
+    # @param other [CyberarmEngine::Vector | Integer | Float] value to subtract from
+    # @param factor [Float] how complete transition to _other_ is, in range [0.0..1.0]
+    # @return [CyberarmEngine::Vector]
     def lerp(other, factor)
       (self - other) * factor.clamp(0.0, 1.0)
     end
 
     # 2D distance using X and Y
+    # @return [Float]
     def distance(other)
       Math.sqrt((@x-other.x)**2 + (@y-other.y)**2)
     end
 
     # 2D distance using X and Z
+    # @return [Float]
     def gl_distance2d(other)
       Math.sqrt((@x-other.x)**2 + (@z-other.z)**2)
     end
 
     # 3D distance using X, Y, and Z
+    # @return [Float]
     def distance3d(other)
       Math.sqrt((@x-other.x)**2 + (@y-other.y)**2 + (@z-other.z)**2)
     end
 
+    # Converts {Vector} to Array
+    # @return [Array]
     def to_a
       [@x, @y, @z, @weight]
     end
 
+    # Converts {Vector} to String
+    # @return [String]
     def to_s
       "X: #{@x}, Y: #{@y}, Z: #{@z}, Weight: #{@weight}"
     end
 
+    # Converts {Vector} to Hash
+    # @return [Hash]
     def to_h
       {x: @x, y: @y, z: @z, weight: @weight}
     end

lib/cyberarm_engine/version.rb

@@ -1,4 +1,4 @@
 module CyberarmEngine
   NAME    = "InDev"
-  VERSION = "0.12.1"
+  VERSION = "0.13.1"
 end