A 3D-texture example with my hacked ruby-processing

To get ruby-processing working with processing-2.0b6 core (and the associated opengl/jogl) required a number of hacks. One of which seemed to lose the ability to run sketches that were explicitly sub-classed from Processing::App, but that is probably no bad thing. Here is the modified textured_cube example, note NORMALIZED is replace by NORMAL in processing-2.0 syntax:-

# TexturedCube
# by Dave Bollinger.
# 
# Drag mouse to rotate cube. Demonstrates use of u/v coords in 
# vertex and effect on texture().


def setup
  size 649, 360, P3D
  @rotx = PI/4
  @roty = PI/4
  @tex = load_image "berlin-1.jpg"
  texture_mode NORMAL  # Changed for processing 2.0
  fill 255
  stroke 44, 48, 32
end

def draw
  background 0
  no_stroke
  translate width/2, height/2, -100
  rotate_x @rotx
  rotate_y @roty
  scale 90
  texture_cube
end

def texture_cube

# Given one texture and six faces, we can easily set up the uv coordinates
# such that four of the faces tile "perfectly" along either u or v, but the other
# two faces cannot be so aligned.  This code tiles "along" u, "around" the X/Z faces
# and fudges the Y faces - the Y faces are arbitrarily aligned such that a
# rotation along the X axis will put the "top" of either texture at the "top"
# of the screen, but is not otherwised aligned with the X/Z faces. (This
# just affects what type of symmetry is required if you need seamless
# tiling all the way around the cube)

begin_shape QUADS

  texture @tex

  # +Z "front" face
  vertex -1, -1,  1, 0, 0
  vertex  1, -1,  1, 1, 0
  vertex  1,  1,  1, 1, 1
  vertex -1,  1,  1, 0, 1

  # -Z "back" face
  vertex  1, -1, -1, 0, 0
  vertex -1, -1, -1, 1, 0
  vertex -1,  1, -1, 1, 1
  vertex  1,  1, -1, 0, 1

  # +Y "bottom" face
  vertex -1,  1,  1, 0, 0
  vertex  1,  1,  1, 1, 0
  vertex  1,  1, -1, 1, 1
  vertex -1,  1, -1, 0, 1

  # -Y "top" face
  vertex -1, -1, -1, 0, 0
  vertex  1, -1, -1, 1, 0
  vertex  1, -1,  1, 1, 1
  vertex -1, -1,  1, 0, 1

  # +X "right" face
  vertex  1, -1,  1, 0, 0
  vertex  1, -1, -1, 1, 0
  vertex  1,  1, -1, 1, 1
  vertex  1,  1,  1, 0, 1

  # -X "left" face
  vertex -1, -1, -1, 0, 0
  vertex -1, -1,  1, 1, 0
  vertex -1,  1,  1, 1, 1
  vertex -1,  1, -1, 0, 1

  end_shape
end

def mouse_dragged
  rate = 0.01
  @rotx += ( pmouse_y - mouse_y ) * rate
  @roty += ( mouse_x - pmouse_x ) * rate
end