From 28acb12efc239663cf2533450e3b40c2cace4901 Mon Sep 17 00:00:00 2001
From: Cyberarm <matthewlikesrobots@gmail.com>
Date: Fri, 23 Mar 2018 15:34:03 -0500
Subject: [PATCH] We can now attach an object to the camera- bit buggy atm.

---
 lib/objects/camera.rb | 58 +++++++++++++++++++++++++++++++++++--------
 lib/window.rb         |  7 +++---
 2 files changed, 52 insertions(+), 13 deletions(-)

diff --git a/lib/objects/camera.rb b/lib/objects/camera.rb
index 86c3222..7757050 100644
--- a/lib/objects/camera.rb
+++ b/lib/objects/camera.rb
@@ -4,21 +4,57 @@ class IMICFPS
     include OpenGL
     include GLU
 
-    attr_accessor :x,:y,:z, :field_of_view, :vertical_angle, :horizontal_angle, :mouse_sensitivity
-    attr_reader :bound_model
+    attr_accessor :x,:y,:z, :field_of_view, :pitch, :yaw, :roll, :mouse_sensitivity
+    attr_reader :game_object
     def initialize(x: 0, y: 0, z: 0, fov: 70.0, distance: 100.0)
       @x,@y,@z = x,y,z
-      @vertical_angle = 0.0
-      @horizontal_angle = 0.0
+      @pitch = 0.0
+      @yaw   = 0.0
+      @roll  = 0.0
       @field_of_view = fov
       @view_distance = distance
 
+      @game_object = nil
+      @distance = 2
+
       self.mouse_x, self.mouse_y = Gosu.screen_width/2, Gosu.screen_height/2
       @true_mouse = Point.new(Gosu.screen_width/2, Gosu.screen_height/2)
       @true_mouse_checked = 0
       @mouse_sensitivity = 20.0
     end
 
+    def attach_to(game_object)
+      raise "Not a game object!" unless game_object.is_a?(GameObject)
+      @game_object = game_object
+    end
+
+    def detach
+      @game_object = nil
+    end
+
+    def distance_from_object
+      @distance
+    end
+
+    def horizontal_distance_from_object
+      distance_from_object * Math.cos(@pitch)
+    end
+
+    def vertical_distance_from_object
+      distance_from_object * Math.sin(@pitch)
+    end
+
+    def position_camera
+      x_offset = horizontal_distance_from_object * Math.sin(@game_object.y_rotation.degrees_to_radians)
+      z_offset = horizontal_distance_from_object * Math.cos(@game_object.y_rotation.degrees_to_radians)
+      # p @game_object.x, @game_object.z;exit
+      @x = @game_object.x - x_offset
+      @y = @game_object.y - 2
+      @z = @game_object.z - z_offset
+
+      @yaw = 180 - @game_object.y_rotation
+    end
+
     def draw
       #glMatrixMode(matrix) indicates that following [matrix] is going to get used
       glMatrixMode(GL_PROJECTION) # The projection matrix is responsible for adding perspective to our scene.
@@ -26,8 +62,8 @@ class IMICFPS
       # Calculates aspect ratio of the window. Gets perspective  view. 45 is degree viewing angle, (0.1, 100) are ranges how deep can we draw into the screen
       gluPerspective(@field_of_view, $window.width / $window.height, 0.1, @view_distance)
       glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST)
-      glRotatef(@vertical_angle,1,0,0)
-      glRotatef(@horizontal_angle,0,1,0)
+      glRotatef(@pitch,1,0,0)
+      glRotatef(@yaw,0,1,0)
       glTranslatef(@x, @y, @z)
 
       glMatrixMode(GL_MODELVIEW) # The modelview matrix is where object information is stored.
@@ -35,11 +71,13 @@ class IMICFPS
     end
 
     def update
+      position_camera if @game_object
+
       if @true_mouse_checked > 2
-        @horizontal_angle-=Float(@true_mouse.x-self.mouse_x)/(@mouse_sensitivity*@field_of_view)*70
-        @vertical_angle-=Float(@true_mouse.y-self.mouse_y)/(@mouse_sensitivity*@field_of_view)*70
-        @horizontal_angle %= 360.0
-        @vertical_angle = @vertical_angle.clamp(-90.0, 90.0)
+        @yaw-=Float(@true_mouse.x-self.mouse_x)/(@mouse_sensitivity*@field_of_view)*70 unless @game_object
+        @pitch-=Float(@true_mouse.y-self.mouse_y)/(@mouse_sensitivity*@field_of_view)*70 unless @game_object
+        @yaw %= 360.0
+        @pitch = @pitch.clamp(-90.0, 90.0)
       else
         @true_mouse_checked+=1
         @true_mouse.x = self.mouse_x
diff --git a/lib/window.rb b/lib/window.rb
index 9a6b55b..50cbe70 100644
--- a/lib/window.rb
+++ b/lib/window.rb
@@ -27,8 +27,9 @@ class IMICFPS
       # Model.new(type: :obj, file_path: "objects/sponza.obj", scale: 1, y: -0.2)
       @terrain = Terrain.new(size: 20, height: 0)
 
-      @camera = Camera.new(x: 0, y: -2, z: 1)
       @player = Player.new(x: 1, y: 0, z: -10)
+      @camera = Camera.new(x: 0, y: -2, z: 1)
+      @camera.attach_to(@player)
 
       @crosshair_size = 10
       @crosshair_thickness = 3
@@ -81,9 +82,9 @@ class IMICFPS
       OpenGL Version: #{glGetString(GL_VERSION)}~
       OpenGL Shader Language Version: #{glGetString(GL_SHADING_LANGUAGE_VERSION)}~
       ~
-      Vertical Angle: #{@camera.vertical_angle.round(2)} Horizontal Angle: #{@camera.horizontal_angle.round(2)} ~
+      Camera pitch: #{@camera.pitch.round(2)} Yaw: #{@camera.yaw.round(2)} Roll #{@camera.roll.round(2)} ~
       Camera X:#{@camera.x.round(2)} Y:#{@camera.y.round(2)} Z:#{@camera.z.round(2)} ~
-      #{if @camera.bound_model then "Actor X:#{@camera.bound_model.x.round(2)} Y:#{@camera.bound_model.y.round(2)} Z:#{@camera.bound_model.z.round(2)}";end} ~
+      #{if @camera.game_object then "Actor X:#{@camera.game_object.x.round(2)} Y:#{@camera.game_object.y.round(2)} Z:#{@camera.game_object.z.round(2)}";end} ~
       Field Of View: #{@camera.field_of_view} ~
       Mouse Sesitivity: #{@camera.mouse_sensitivity} ~
       Faces: #{@number_of_faces} ~