Simplify RGB cube by using Vec2D, ArcBall and GfxRender

Author: monkstone

processing_app/basics/form/rgb_cube.rb

@@ -1,73 +1,69 @@
 #!/usr/bin/env jruby
+# frozen_string_literal: true
+
 require 'propane'
+require 'arcball'
+java_import 'monkstone.vecmath.GfxRender'
 # RGB Cube.
 #
 # The three primary colors of the additive color model are red, green, and blue.
 # This RGB color cube displays smooth transitions between these colors.
 class RgbCube < Propane::App
-
   attr_reader :box_points
 
   def setup
     sketch_title 'RGB Cube'
     no_stroke
-    color_mode RGB, 2
-    @xmag = 0
-    @ymag = 0
-    @new_xmag = 0
-    @new_ymag = 0
-    # Math.since each point is used three times
+    Processing::ArcBall.init(self, width / 2, height / 2)
+
     @box_points = {
-      top_front_left: [-1,  1,  1],
-      top_front_right: [1,  1,  1],
-      top_back_right: [1,  1, -1],
-      top_back_left: [-1,  1, -1],
-      bottom_front_left: [-1, -1,  1],
-      bottom_front_right: [1, -1,  1],
-      bottom_back_right: [1, -1, -1],
-      bottom_back_left: [-1, -1, -1]
+      top_front_left: Vec3D.new(-90,  90,  90),
+      top_front_right: Vec3D.new(90,  90,  90),
+      top_back_right: Vec3D.new(90,  90, -90),
+      top_back_left: Vec3D.new(-90,  90, -90),
+      bottom_front_left: Vec3D.new(-90, -90,  90),
+      bottom_front_right: Vec3D.new(90, -90,  90),
+      bottom_back_right: Vec3D.new(90, -90, -90),
+      bottom_back_left: Vec3D.new(-90, -90, -90)
     }
     # a box from defined points
     @box = {
-      top: [box_points[:top_front_left], box_points[:top_front_right], box_points[:top_back_right], box_points[:top_back_left]],
-      front: [box_points[:top_front_left], box_points[:top_front_right], box_points[:bottom_front_right], box_points[:bottom_front_left]],
-      left: [box_points[:top_front_left], box_points[:bottom_front_left], box_points[:bottom_back_left], box_points[:top_back_left]],
-      back: [box_points[:top_back_left], box_points[:top_back_right], box_points[:bottom_back_right], box_points[:bottom_back_left]],
-      right: [box_points[:top_back_right], box_points[:bottom_back_right], box_points[:bottom_front_right], box_points[:top_front_right]],
-      bottom: [box_points[:bottom_front_left], box_points[:bottom_front_right], box_points[:bottom_back_right], box_points[:bottom_back_left]]
+      top: [box_points[:top_front_left], box_points[:top_front_right], box_points[:top_back_right],
+            box_points[:top_back_left]],
+      front: [box_points[:top_front_left], box_points[:top_front_right], box_points[:bottom_front_right],
+              box_points[:bottom_front_left]],
+      left: [box_points[:top_front_left], box_points[:bottom_front_left], box_points[:bottom_back_left],
+             box_points[:top_back_left]],
+      back: [box_points[:top_back_left], box_points[:top_back_right], box_points[:bottom_back_right],
+             box_points[:bottom_back_left]],
+      right: [box_points[:top_back_right], box_points[:bottom_back_right], box_points[:bottom_front_right],
+              box_points[:top_front_right]],
+      bottom: [box_points[:bottom_front_left], box_points[:bottom_front_right], box_points[:bottom_back_right],
+               box_points[:bottom_back_left]]
     }
   end
 
   def draw
     background 1
-    push_matrix
-    translate width / 2, height / 2, -30
-    @new_xmag = mouse_x.to_f / width * TAU
-    @new_ymag = mouse_y.to_f / height * TAU
-    diff = @xmag - @new_xmag
-    @xmag -= diff / 4 if diff.abs > 0.01
-    diff = @ymag - @new_ymag
-    @ymag -= diff / 4 if diff.abs > 0.01
-    rotate_x(-@ymag)
-    rotate_y(-@xmag)
-    scale 90
     begin_shape QUADS
-    %i(top front left back right bottom).each do |s|
+    %i[top front left back right bottom].each do |s|
       @box[s].each do |p|
         fill_from_points p
-        vertex_from_points p
+        p.to_vertex(renderer)
       end
     end
     end_shape
-    pop_matrix
   end
 
   def fill_from_points(points)
-    fill points[0] + 1, points[1] + 1, points[2] + 1 # "+1" translates -1,1 to 0,2
+    red = map1d(points.x, -90..90, 0..255)
+    blue = map1d(points.y, -90..90, 0..255)
+    green = map1d(points.z, -90..90, 0..255)
+    fill(red, blue, green)
   end
 
-  def vertex_from_points(points)
-    vertex(*points)
+  def renderer
+    @renderer ||= GfxRender.new(g)
   end
 
   def settings