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author Robert McIntyre <rlm@mit.edu>
date Thu, 29 May 2014 17:02:17 -0400
parents 763d13f77e03
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rlm@37 1 #+title: Simulated Sense of Touch
rlm@0 2 #+author: Robert McIntyre
rlm@0 3 #+email: rlm@mit.edu
rlm@37 4 #+description: Simulated touch for AI research using JMonkeyEngine and clojure.
rlm@37 5 #+keywords: simulation, tactile sense, jMonkeyEngine3, clojure
rlm@4 6 #+SETUPFILE: ../../aurellem/org/setup.org
rlm@4 7 #+INCLUDE: ../../aurellem/org/level-0.org
rlm@0 8
rlm@37 9 * Touch
rlm@0 10
rlm@226 11 Touch is critical to navigation and spatial reasoning and as such I
rlm@226 12 need a simulated version of it to give to my AI creatures.
rlm@0 13
rlm@306 14 Human skin has a wide array of touch sensors, each of which specialize
rlm@228 15 in detecting different vibrational modes and pressures. These sensors
rlm@228 16 can integrate a vast expanse of skin (i.e. your entire palm), or a
rlm@228 17 tiny patch of skin at the tip of your finger. The hairs of the skin
rlm@228 18 help detect objects before they even come into contact with the skin
rlm@247 19 proper.
rlm@228 20
rlm@248 21 However, touch in my simulated world can not exactly correspond to
rlm@248 22 human touch because my creatures are made out of completely rigid
rlm@248 23 segments that don't deform like human skin.
rlm@248 24
rlm@228 25 Instead of measuring deformation or vibration, I surround each rigid
rlm@247 26 part with a plenitude of hair-like objects (/feelers/) which do not
rlm@247 27 interact with the physical world. Physical objects can pass through
rlm@248 28 them with no effect. The feelers are able to tell when other objects
rlm@248 29 pass through them, and they constantly report how much of their extent
rlm@248 30 is covered. So even though the creature's body parts do not deform,
rlm@248 31 the feelers create a margin around those body parts which achieves a
rlm@248 32 sense of touch which is a hybrid between a human's sense of
rlm@248 33 deformation and sense from hairs.
rlm@228 34
rlm@306 35 Implementing touch in jMonkeyEngine follows a different technical route
rlm@228 36 than vision and hearing. Those two senses piggybacked off
rlm@228 37 jMonkeyEngine's 3D audio and video rendering subsystems. To simulate
rlm@247 38 touch, I use jMonkeyEngine's physics system to execute many small
rlm@247 39 collision detections, one for each feeler. The placement of the
rlm@247 40 feelers is determined by a UV-mapped image which shows where each
rlm@247 41 feeler should be on the 3D surface of the body.
rlm@228 42
rlm@229 43 * Defining Touch Meta-Data in Blender
rlm@229 44
rlm@245 45 Each geometry can have a single UV map which describes the position of
rlm@247 46 the feelers which will constitute its sense of touch. This image path
rlm@245 47 is stored under the "touch" key. The image itself is black and white,
rlm@247 48 with black meaning a feeler length of 0 (no feeler is present) and
rlm@247 49 white meaning a feeler length of =scale=, which is a float stored
rlm@247 50 under the key "scale".
rlm@229 51
rlm@231 52 #+name: meta-data
rlm@0 53 #+begin_src clojure
rlm@229 54 (defn tactile-sensor-profile
rlm@229 55 "Return the touch-sensor distribution image in BufferedImage format,
rlm@229 56 or nil if it does not exist."
rlm@229 57 [#^Geometry obj]
rlm@229 58 (if-let [image-path (meta-data obj "touch")]
rlm@229 59 (load-image image-path)))
rlm@233 60
rlm@233 61 (defn tactile-scale
rlm@247 62 "Return the length of each feeler. Default scale is 0.01
rlm@247 63 jMonkeyEngine units."
rlm@233 64 [#^Geometry obj]
rlm@233 65 (if-let [scale (meta-data obj "scale")]
rlm@233 66 scale 0.1))
rlm@228 67 #+end_src
rlm@156 68
rlm@246 69 Here is an example of a UV-map which specifies the position of touch
rlm@247 70 sensors along the surface of the upper segment of the worm.
rlm@229 71
rlm@246 72 #+attr_html: width=755
rlm@246 73 #+caption: This is the tactile-sensor-profile for the upper segment of the worm. It defines regions of high touch sensitivity (where there are many white pixels) and regions of low sensitivity (where white pixels are sparse).
rlm@246 74 [[../images/finger-UV.png]]
rlm@234 75
rlm@247 76 * Implementation Summary
rlm@247 77
rlm@247 78 To simulate touch there are three conceptual steps. For each solid
rlm@247 79 object in the creature, you first have to get UV image and scale
rlm@306 80 parameter which define the position and length of the feelers. Then,
rlm@430 81 you use the triangles which comprise the mesh and the UV data stored in
rlm@247 82 the mesh to determine the world-space position and orientation of each
rlm@248 83 feeler. Then once every frame, update these positions and orientations
rlm@248 84 to match the current position and orientation of the object, and use
rlm@247 85 physics collision detection to gather tactile data.
rlm@238 86
rlm@247 87 Extracting the meta-data has already been described. The third step,
rlm@273 88 physics collision detection, is handled in =touch-kernel=.
rlm@247 89 Translating the positions and orientations of the feelers from the
rlm@248 90 UV-map to world-space is itself a three-step process.
rlm@239 91
rlm@238 92 - Find the triangles which make up the mesh in pixel-space and in
rlm@273 93 world-space. =triangles= =pixel-triangles=.
rlm@239 94
rlm@247 95 - Find the coordinates of each feeler in world-space. These are the
rlm@273 96 origins of the feelers. =feeler-origins=.
rlm@239 97
rlm@238 98 - Calculate the normals of the triangles in world space, and add
rlm@238 99 them to each of the origins of the feelers. These are the
rlm@273 100 normalized coordinates of the tips of the feelers. =feeler-tips=.
rlm@239 101
rlm@247 102 * Triangle Math
rlm@306 103 ** Shrapnel Conversion Functions
rlm@239 104
rlm@247 105 #+name: triangles-1
rlm@247 106 #+begin_src clojure
rlm@247 107 (defn vector3f-seq [#^Vector3f v]
rlm@247 108 [(.getX v) (.getY v) (.getZ v)])
rlm@247 109
rlm@247 110 (defn triangle-seq [#^Triangle tri]
rlm@247 111 [(vector3f-seq (.get1 tri))
rlm@247 112 (vector3f-seq (.get2 tri))
rlm@247 113 (vector3f-seq (.get3 tri))])
rlm@247 114
rlm@247 115 (defn ->vector3f
rlm@247 116 ([coords] (Vector3f. (nth coords 0 0)
rlm@247 117 (nth coords 1 0)
rlm@247 118 (nth coords 2 0))))
rlm@247 119
rlm@247 120 (defn ->triangle [points]
rlm@247 121 (apply #(Triangle. %1 %2 %3) (map ->vector3f points)))
rlm@247 122 #+end_src
rlm@247 123
rlm@306 124 It is convenient to treat a =Triangle= as a vector of vectors, and a
rlm@255 125 =Vector2f= or =Vector3f= as vectors of floats. (->vector3f) and
rlm@273 126 (->triangle) undo the operations of =vector3f-seq= and
rlm@273 127 =triangle-seq=. If these classes implemented =Iterable= then =seq=
rlm@306 128 would work on them automatically.
rlm@248 129
rlm@247 130 ** Decomposing a 3D shape into Triangles
rlm@247 131
rlm@248 132 The rigid objects which make up a creature have an underlying
rlm@247 133 =Geometry=, which is a =Mesh= plus a =Material= and other important
rlm@248 134 data involved with displaying the object.
rlm@247 135
rlm@247 136 A =Mesh= is composed of =Triangles=, and each =Triangle= has three
rlm@306 137 vertices which have coordinates in world space and UV space.
rlm@247 138
rlm@430 139 Here, =triangles= gets all the world-space triangles which comprise a
rlm@273 140 mesh, while =pixel-triangles= gets those same triangles expressed in
rlm@247 141 pixel coordinates (which are UV coordinates scaled to fit the height
rlm@247 142 and width of the UV image).
rlm@247 143
rlm@247 144 #+name: triangles-2
rlm@247 145 #+begin_src clojure
rlm@247 146 (in-ns 'cortex.touch)
rlm@247 147 (defn triangle
rlm@247 148 "Get the triangle specified by triangle-index from the mesh."
rlm@247 149 [#^Geometry geo triangle-index]
rlm@247 150 (triangle-seq
rlm@247 151 (let [scratch (Triangle.)]
rlm@247 152 (.getTriangle (.getMesh geo) triangle-index scratch) scratch)))
rlm@247 153
rlm@247 154 (defn triangles
rlm@430 155 "Return a sequence of all the Triangles which comprise a given
rlm@247 156 Geometry."
rlm@247 157 [#^Geometry geo]
rlm@247 158 (map (partial triangle geo) (range (.getTriangleCount (.getMesh geo)))))
rlm@247 159
rlm@247 160 (defn triangle-vertex-indices
rlm@247 161 "Get the triangle vertex indices of a given triangle from a given
rlm@247 162 mesh."
rlm@247 163 [#^Mesh mesh triangle-index]
rlm@247 164 (let [indices (int-array 3)]
rlm@247 165 (.getTriangle mesh triangle-index indices)
rlm@247 166 (vec indices)))
rlm@247 167
rlm@247 168 (defn vertex-UV-coord
rlm@247 169 "Get the UV-coordinates of the vertex named by vertex-index"
rlm@247 170 [#^Mesh mesh vertex-index]
rlm@247 171 (let [UV-buffer
rlm@247 172 (.getData
rlm@247 173 (.getBuffer
rlm@247 174 mesh
rlm@247 175 VertexBuffer$Type/TexCoord))]
rlm@247 176 [(.get UV-buffer (* vertex-index 2))
rlm@247 177 (.get UV-buffer (+ 1 (* vertex-index 2)))]))
rlm@247 178
rlm@247 179 (defn pixel-triangle [#^Geometry geo image index]
rlm@247 180 (let [mesh (.getMesh geo)
rlm@247 181 width (.getWidth image)
rlm@247 182 height (.getHeight image)]
rlm@247 183 (vec (map (fn [[u v]] (vector (* width u) (* height v)))
rlm@247 184 (map (partial vertex-UV-coord mesh)
rlm@247 185 (triangle-vertex-indices mesh index))))))
rlm@247 186
rlm@248 187 (defn pixel-triangles
rlm@248 188 "The pixel-space triangles of the Geometry, in the same order as
rlm@248 189 (triangles geo)"
rlm@248 190 [#^Geometry geo image]
rlm@248 191 (let [height (.getHeight image)
rlm@248 192 width (.getWidth image)]
rlm@248 193 (map (partial pixel-triangle geo image)
rlm@248 194 (range (.getTriangleCount (.getMesh geo))))))
rlm@247 195 #+end_src
rlm@247 196 ** The Affine Transform from one Triangle to Another
rlm@247 197
rlm@273 198 =pixel-triangles= gives us the mesh triangles expressed in pixel
rlm@273 199 coordinates and =triangles= gives us the mesh triangles expressed in
rlm@247 200 world coordinates. The tactile-sensor-profile gives the position of
rlm@248 201 each feeler in pixel-space. In order to convert pixel-space
rlm@247 202 coordinates into world-space coordinates we need something that takes
rlm@247 203 coordinates on the surface of one triangle and gives the corresponding
rlm@247 204 coordinates on the surface of another triangle.
rlm@247 205
rlm@247 206 Triangles are [[http://mathworld.wolfram.com/AffineTransformation.html ][affine]], which means any triangle can be transformed into
rlm@247 207 any other by a combination of translation, scaling, and
rlm@248 208 rotation. The affine transformation from one triangle to another
rlm@247 209 is readily computable if the triangle is expressed in terms of a $4x4$
rlm@247 210 matrix.
rlm@247 211
rlm@247 212 \begin{bmatrix}
rlm@247 213 x_1 & x_2 & x_3 & n_x \\
rlm@247 214 y_1 & y_2 & y_3 & n_y \\
rlm@247 215 z_1 & z_2 & z_3 & n_z \\
rlm@247 216 1 & 1 & 1 & 1
rlm@247 217 \end{bmatrix}
rlm@247 218
rlm@306 219 Here, the first three columns of the matrix are the vertices of the
rlm@247 220 triangle. The last column is the right-handed unit normal of the
rlm@247 221 triangle.
rlm@247 222
rlm@247 223 With two triangles $T_{1}$ and $T_{2}$ each expressed as a matrix like
rlm@247 224 above, the affine transform from $T_{1}$ to $T_{2}$ is
rlm@247 225
rlm@247 226 $T_{2}T_{1}^{-1}$
rlm@247 227
rlm@306 228 The clojure code below recapitulates the formulas above, using
rlm@248 229 jMonkeyEngine's =Matrix4f= objects, which can describe any affine
rlm@248 230 transformation.
rlm@247 231
rlm@247 232 #+name: triangles-3
rlm@247 233 #+begin_src clojure
rlm@247 234 (in-ns 'cortex.touch)
rlm@247 235
rlm@247 236 (defn triangle->matrix4f
rlm@247 237 "Converts the triangle into a 4x4 matrix: The first three columns
rlm@247 238 contain the vertices of the triangle; the last contains the unit
rlm@247 239 normal of the triangle. The bottom row is filled with 1s."
rlm@247 240 [#^Triangle t]
rlm@247 241 (let [mat (Matrix4f.)
rlm@247 242 [vert-1 vert-2 vert-3]
rlm@430 243 (mapv #(.get t %) (range 3))
rlm@247 244 unit-normal (do (.calculateNormal t)(.getNormal t))
rlm@247 245 vertices [vert-1 vert-2 vert-3 unit-normal]]
rlm@247 246 (dorun
rlm@247 247 (for [row (range 4) col (range 3)]
rlm@247 248 (do
rlm@247 249 (.set mat col row (.get (vertices row) col))
rlm@247 250 (.set mat 3 row 1)))) mat))
rlm@247 251
rlm@247 252 (defn triangles->affine-transform
rlm@247 253 "Returns the affine transformation that converts each vertex in the
rlm@247 254 first triangle into the corresponding vertex in the second
rlm@247 255 triangle."
rlm@247 256 [#^Triangle tri-1 #^Triangle tri-2]
rlm@247 257 (.mult
rlm@247 258 (triangle->matrix4f tri-2)
rlm@247 259 (.invert (triangle->matrix4f tri-1))))
rlm@247 260 #+end_src
rlm@247 261 ** Triangle Boundaries
rlm@247 262
rlm@247 263 For efficiency's sake I will divide the tactile-profile image into
rlm@247 264 small squares which inscribe each pixel-triangle, then extract the
rlm@247 265 points which lie inside the triangle and map them to 3D-space using
rlm@273 266 =triangle-transform= above. To do this I need a function,
rlm@273 267 =convex-bounds= which finds the smallest box which inscribes a 2D
rlm@247 268 triangle.
rlm@247 269
rlm@273 270 =inside-triangle?= determines whether a point is inside a triangle
rlm@247 271 in 2D pixel-space.
rlm@247 272
rlm@247 273 #+name: triangles-4
rlm@247 274 #+begin_src clojure
rlm@247 275 (defn convex-bounds
rlm@247 276 "Returns the smallest square containing the given vertices, as a
rlm@247 277 vector of integers [left top width height]."
rlm@247 278 [verts]
rlm@247 279 (let [xs (map first verts)
rlm@247 280 ys (map second verts)
rlm@247 281 x0 (Math/floor (apply min xs))
rlm@247 282 y0 (Math/floor (apply min ys))
rlm@247 283 x1 (Math/ceil (apply max xs))
rlm@247 284 y1 (Math/ceil (apply max ys))]
rlm@247 285 [x0 y0 (- x1 x0) (- y1 y0)]))
rlm@247 286
rlm@247 287 (defn same-side?
rlm@247 288 "Given the points p1 and p2 and the reference point ref, is point p
rlm@247 289 on the same side of the line that goes through p1 and p2 as ref is?"
rlm@247 290 [p1 p2 ref p]
rlm@247 291 (<=
rlm@247 292 0
rlm@247 293 (.dot
rlm@247 294 (.cross (.subtract p2 p1) (.subtract p p1))
rlm@247 295 (.cross (.subtract p2 p1) (.subtract ref p1)))))
rlm@247 296
rlm@247 297 (defn inside-triangle?
rlm@247 298 "Is the point inside the triangle?"
rlm@247 299 {:author "Dylan Holmes"}
rlm@247 300 [#^Triangle tri #^Vector3f p]
rlm@247 301 (let [[vert-1 vert-2 vert-3] [(.get1 tri) (.get2 tri) (.get3 tri)]]
rlm@247 302 (and
rlm@247 303 (same-side? vert-1 vert-2 vert-3 p)
rlm@247 304 (same-side? vert-2 vert-3 vert-1 p)
rlm@247 305 (same-side? vert-3 vert-1 vert-2 p))))
rlm@247 306 #+end_src
rlm@247 307
rlm@247 308 * Feeler Coordinates
rlm@247 309
rlm@247 310 The triangle-related functions above make short work of calculating
rlm@247 311 the positions and orientations of each feeler in world-space.
rlm@247 312
rlm@247 313 #+name: sensors
rlm@247 314 #+begin_src clojure
rlm@247 315 (in-ns 'cortex.touch)
rlm@247 316
rlm@247 317 (defn feeler-pixel-coords
rlm@247 318 "Returns the coordinates of the feelers in pixel space in lists, one
rlm@247 319 list for each triangle, ordered in the same way as (triangles) and
rlm@247 320 (pixel-triangles)."
rlm@247 321 [#^Geometry geo image]
rlm@247 322 (map
rlm@247 323 (fn [pixel-triangle]
rlm@247 324 (filter
rlm@247 325 (fn [coord]
rlm@247 326 (inside-triangle? (->triangle pixel-triangle)
rlm@247 327 (->vector3f coord)))
rlm@247 328 (white-coordinates image (convex-bounds pixel-triangle))))
rlm@247 329 (pixel-triangles geo image)))
rlm@247 330
rlm@247 331 (defn feeler-world-coords
rlm@247 332 "Returns the coordinates of the feelers in world space in lists, one
rlm@247 333 list for each triangle, ordered in the same way as (triangles) and
rlm@247 334 (pixel-triangles)."
rlm@247 335 [#^Geometry geo image]
rlm@247 336 (let [transforms
rlm@247 337 (map #(triangles->affine-transform
rlm@247 338 (->triangle %1) (->triangle %2))
rlm@247 339 (pixel-triangles geo image)
rlm@247 340 (triangles geo))]
rlm@247 341 (map (fn [transform coords]
rlm@247 342 (map #(.mult transform (->vector3f %)) coords))
rlm@247 343 transforms (feeler-pixel-coords geo image))))
rlm@247 344
rlm@247 345 (defn feeler-origins
rlm@247 346 "The world space coordinates of the root of each feeler."
rlm@247 347 [#^Geometry geo image]
rlm@247 348 (reduce concat (feeler-world-coords geo image)))
rlm@247 349
rlm@247 350 (defn feeler-tips
rlm@247 351 "The world space coordinates of the tip of each feeler."
rlm@247 352 [#^Geometry geo image]
rlm@247 353 (let [world-coords (feeler-world-coords geo image)
rlm@247 354 normals
rlm@247 355 (map
rlm@247 356 (fn [triangle]
rlm@247 357 (.calculateNormal triangle)
rlm@247 358 (.clone (.getNormal triangle)))
rlm@247 359 (map ->triangle (triangles geo)))]
rlm@247 360
rlm@247 361 (mapcat (fn [origins normal]
rlm@247 362 (map #(.add % normal) origins))
rlm@247 363 world-coords normals)))
rlm@247 364
rlm@247 365 (defn touch-topology
rlm@247 366 "touch-topology? is not a function."
rlm@247 367 [#^Geometry geo image]
rlm@247 368 (collapse (reduce concat (feeler-pixel-coords geo image))))
rlm@247 369 #+end_src
rlm@247 370 * Simulated Touch
rlm@247 371
rlm@273 372 =touch-kernel= generates functions to be called from within a
rlm@247 373 simulation that perform the necessary physics collisions to collect
rlm@273 374 tactile data, and =touch!= recursively applies it to every node in
rlm@247 375 the creature.
rlm@238 376
rlm@233 377 #+name: kernel
rlm@233 378 #+begin_src clojure
rlm@233 379 (in-ns 'cortex.touch)
rlm@233 380
rlm@244 381 (defn set-ray [#^Ray ray #^Matrix4f transform
rlm@244 382 #^Vector3f origin #^Vector3f tip]
rlm@306 383 ;; Doing everything locally reduces garbage collection by enough to
rlm@243 384 ;; be worth it.
rlm@243 385 (.mult transform origin (.getOrigin ray))
rlm@243 386 (.mult transform tip (.getDirection ray))
rlm@249 387 (.subtractLocal (.getDirection ray) (.getOrigin ray))
rlm@249 388 (.normalizeLocal (.getDirection ray)))
rlm@242 389
rlm@249 390 (import com.jme3.math.FastMath)
rlm@249 391
rlm@233 392 (defn touch-kernel
rlm@234 393 "Constructs a function which will return tactile sensory data from
rlm@234 394 'geo when called from inside a running simulation"
rlm@234 395 [#^Geometry geo]
rlm@243 396 (if-let
rlm@243 397 [profile (tactile-sensor-profile geo)]
rlm@243 398 (let [ray-reference-origins (feeler-origins geo profile)
rlm@243 399 ray-reference-tips (feeler-tips geo profile)
rlm@244 400 ray-length (tactile-scale geo)
rlm@243 401 current-rays (map (fn [_] (Ray.)) ray-reference-origins)
rlm@249 402 topology (touch-topology geo profile)
rlm@249 403 correction (float (* ray-length -0.2))]
rlm@249 404
rlm@249 405 ;; slight tolerance for very close collisions.
rlm@249 406 (dorun
rlm@249 407 (map (fn [origin tip]
rlm@249 408 (.addLocal origin (.mult (.subtract tip origin)
rlm@249 409 correction)))
rlm@249 410 ray-reference-origins ray-reference-tips))
rlm@244 411 (dorun (map #(.setLimit % ray-length) current-rays))
rlm@233 412 (fn [node]
rlm@243 413 (let [transform (.getWorldMatrix geo)]
rlm@243 414 (dorun
rlm@244 415 (map (fn [ray ref-origin ref-tip]
rlm@244 416 (set-ray ray transform ref-origin ref-tip))
rlm@243 417 current-rays ray-reference-origins
rlm@244 418 ray-reference-tips))
rlm@233 419 (vector
rlm@243 420 topology
rlm@233 421 (vec
rlm@243 422 (for [ray current-rays]
rlm@233 423 (do
rlm@233 424 (let [results (CollisionResults.)]
rlm@233 425 (.collideWith node ray results)
rlm@233 426 (let [touch-objects
rlm@233 427 (filter #(not (= geo (.getGeometry %)))
rlm@249 428 results)
rlm@249 429 limit (.getLimit ray)]
rlm@233 430 [(if (empty? touch-objects)
rlm@249 431 limit
rlm@249 432 (let [response
rlm@249 433 (apply min (map #(.getDistance %)
rlm@249 434 touch-objects))]
rlm@249 435 (FastMath/clamp
rlm@249 436 (float
rlm@283 437 (if (> response limit) (float 0.0)
rlm@249 438 (+ response correction)))
rlm@249 439 (float 0.0)
rlm@249 440 limit)))
rlm@249 441 limit])))))))))))
rlm@233 442
rlm@233 443 (defn touch!
rlm@233 444 "Endow the creature with the sense of touch. Returns a sequence of
rlm@306 445 functions, one for each body part with a tactile-sensor-profile,
rlm@233 446 each of which when called returns sensory data for that body part."
rlm@233 447 [#^Node creature]
rlm@233 448 (filter
rlm@233 449 (comp not nil?)
rlm@233 450 (map touch-kernel
rlm@233 451 (filter #(isa? (class %) Geometry)
rlm@233 452 (node-seq creature)))))
rlm@233 453 #+end_src
rlm@233 454
rlm@249 455 #+results: kernel
rlm@249 456 : #'cortex.touch/touch!
rlm@249 457
rlm@247 458 * Visualizing Touch
rlm@238 459
rlm@249 460 Each feeler is represented in the image as a single pixel. The
rlm@306 461 greyscale value of each pixel represents how deep the feeler
rlm@249 462 represented by that pixel is inside another object. Black means that
rlm@249 463 nothing is touching the feeler, while white means that the feeler is
rlm@249 464 completely inside another object, which is presumably flush with the
rlm@249 465 surface of the triangle from which the feeler originates.
rlm@249 466
rlm@233 467 #+name: visualization
rlm@233 468 #+begin_src clojure
rlm@233 469 (in-ns 'cortex.touch)
rlm@233 470
rlm@233 471 (defn touch->gray
rlm@306 472 "Convert a pair of [distance, max-distance] into a gray-scale pixel."
rlm@233 473 [distance max-distance]
rlm@245 474 (gray (- 255 (rem (int (* 255 (/ distance max-distance))) 256))))
rlm@233 475
rlm@233 476 (defn view-touch
rlm@245 477 "Creates a function which accepts a list of touch sensor-data and
rlm@233 478 displays each element to the screen."
rlm@233 479 []
rlm@233 480 (view-sense
rlm@246 481 (fn [[coords sensor-data]]
rlm@233 482 (let [image (points->image coords)]
rlm@233 483 (dorun
rlm@233 484 (for [i (range (count coords))]
rlm@250 485 (.setRGB image ((coords i) 0) ((coords i) 1)
rlm@250 486 (apply touch->gray (sensor-data i)))))
rlm@283 487 image))))
rlm@233 488 #+end_src
rlm@249 489
rlm@249 490 #+results: visualization
rlm@249 491 : #'cortex.touch/view-touch
rlm@249 492
rlm@250 493 * Basic Test of Touch
rlm@249 494
rlm@249 495 The worm's sense of touch is a bit complicated, so for this basic test
rlm@249 496 I'll use a new creature --- a simple cube which has touch sensors
rlm@249 497 evenly distributed along each of its sides.
rlm@249 498
rlm@253 499 #+name: test-touch-0
rlm@249 500 #+begin_src clojure
rlm@249 501 (in-ns 'cortex.test.touch)
rlm@249 502
rlm@249 503 (defn touch-cube []
rlm@249 504 (load-blender-model "Models/test-touch/touch-cube.blend"))
rlm@249 505 #+end_src
rlm@249 506
rlm@253 507 ** The Touch Cube
rlm@249 508 #+begin_html
rlm@249 509 <div class="figure">
rlm@249 510 <center>
rlm@249 511 <video controls="controls" width="500">
rlm@249 512 <source src="../video/touch-cube.ogg" type="video/ogg"
rlm@249 513 preload="none" poster="../images/aurellem-1280x480.png" />
rlm@249 514 </video>
rlm@309 515 <br> <a href="http://youtu.be/aEao4m8meAI"> YouTube </a>
rlm@249 516 </center>
rlm@249 517 <p>A simple creature with evenly distributed touch sensors.</p>
rlm@249 518 </div>
rlm@249 519 #+end_html
rlm@249 520
rlm@249 521 The tactile-sensor-profile image for this simple creature looks like
rlm@249 522 this:
rlm@249 523
rlm@249 524 #+attr_html: width=500
rlm@249 525 #+caption: The distribution of feelers along the touch-cube. The colors of the faces are irrelevant; only the white pixels specify feelers.
rlm@249 526 [[../images/touch-profile.png]]
rlm@249 527
rlm@253 528 #+name: test-touch-1
rlm@249 529 #+begin_src clojure
rlm@249 530 (in-ns 'cortex.test.touch)
rlm@249 531
rlm@249 532 (defn test-basic-touch
rlm@321 533 "Testing touch:
rlm@321 534 You should see a cube fall onto a table. There is a cross-shaped
rlm@321 535 display which reports the cube's sensation of touch. This display
rlm@321 536 should change when the cube hits the table, and whenever you hit
rlm@321 537 the cube with balls.
rlm@321 538
rlm@321 539 Keys:
rlm@321 540 <space> : fire ball"
rlm@249 541 ([] (test-basic-touch false))
rlm@249 542 ([record?]
rlm@249 543 (let [the-cube (doto (touch-cube) (body!))
rlm@249 544 touch (touch! the-cube)
rlm@249 545 touch-display (view-touch)]
rlm@250 546 (world
rlm@250 547 (nodify [the-cube
rlm@250 548 (box 10 1 10 :position (Vector3f. 0 -10 0)
rlm@250 549 :color ColorRGBA/Gray :mass 0)])
rlm@250 550
rlm@250 551 standard-debug-controls
rlm@250 552
rlm@250 553 (fn [world]
rlm@340 554 (let [timer (IsoTimer. 60)]
rlm@340 555 (.setTimer world timer)
rlm@340 556 (display-dilated-time world timer))
rlm@250 557 (if record?
rlm@250 558 (Capture/captureVideo
rlm@250 559 world
rlm@250 560 (File. "/home/r/proj/cortex/render/touch-cube/main-view/")))
rlm@250 561 (speed-up world)
rlm@250 562 (light-up-everything world))
rlm@250 563
rlm@250 564 (fn [world tpf]
rlm@250 565 (touch-display
rlm@250 566 (map #(% (.getRootNode world)) touch)
rlm@250 567 (if record?
rlm@250 568 (File. "/home/r/proj/cortex/render/touch-cube/touch/"))))))))
rlm@250 569 #+end_src
rlm@249 570
rlm@340 571 #+results: test-touch-1
rlm@340 572 : #'cortex.test.touch/test-basic-touch
rlm@340 573
rlm@250 574 ** Basic Touch Demonstration
rlm@249 575
rlm@250 576 #+begin_html
rlm@250 577 <div class="figure">
rlm@250 578 <center>
rlm@250 579 <video controls="controls" width="755">
rlm@250 580 <source src="../video/basic-touch.ogg" type="video/ogg"
rlm@250 581 preload="none" poster="../images/aurellem-1280x480.png" />
rlm@250 582 </video>
rlm@309 583 <br> <a href="http://youtu.be/8xNEtD-a8f0"> YouTube </a>
rlm@250 584 </center>
rlm@250 585 <p>The simple creature responds to touch.</p>
rlm@250 586 </div>
rlm@250 587 #+end_html
rlm@249 588
rlm@250 589 ** Generating the Basic Touch Video
rlm@253 590 #+name: magick4
rlm@250 591 #+begin_src clojure
rlm@250 592 (ns cortex.video.magick4
rlm@250 593 (:import java.io.File)
rlm@316 594 (:use clojure.java.shell))
rlm@250 595
rlm@250 596 (defn images [path]
rlm@250 597 (sort (rest (file-seq (File. path)))))
rlm@250 598
rlm@250 599 (def base "/home/r/proj/cortex/render/touch-cube/")
rlm@250 600
rlm@250 601 (defn pics [file]
rlm@250 602 (images (str base file)))
rlm@250 603
rlm@250 604 (defn combine-images []
rlm@250 605 (let [main-view (pics "main-view")
rlm@250 606 touch (pics "touch/0")
rlm@250 607 background (repeat 9001 (File. (str base "background.png")))
rlm@250 608 targets (map
rlm@250 609 #(File. (str base "out/" (format "%07d.png" %)))
rlm@250 610 (range 0 (count main-view)))]
rlm@250 611 (dorun
rlm@250 612 (pmap
rlm@250 613 (comp
rlm@250 614 (fn [[background main-view touch target]]
rlm@250 615 (println target)
rlm@250 616 (sh "convert"
rlm@250 617 touch
rlm@250 618 "-resize" "x300"
rlm@250 619 "-rotate" "180"
rlm@250 620 background
rlm@250 621 "-swap" "0,1"
rlm@250 622 "-geometry" "+776+129"
rlm@250 623 "-composite"
rlm@250 624 main-view "-geometry" "+66+21" "-composite"
rlm@250 625 target))
rlm@250 626 (fn [& args] (map #(.getCanonicalPath %) args)))
rlm@250 627 background main-view touch targets))))
rlm@249 628 #+end_src
rlm@249 629
rlm@252 630 #+begin_src sh :results silent
rlm@312 631 cd ~/proj/cortex/render/touch-cube/
rlm@252 632 ffmpeg -r 60 -i out/%07d.png -b:v 9000k -c:v libtheora basic-touch.ogg
rlm@252 633 #+end_src
rlm@250 634
rlm@312 635 #+begin_src sh :results silent
rlm@312 636 cd ~/proj/cortex/render/touch-cube/
rlm@312 637 ffmpeg -r 30 -i blender-intro/%07d.png -b:v 9000k -c:v libtheora touch-cube.ogg
rlm@312 638 #+end_src
rlm@312 639
rlm@232 640 * Adding Touch to the Worm
rlm@232 641
rlm@253 642 #+name: test-touch-2
rlm@232 643 #+begin_src clojure
rlm@253 644 (in-ns 'cortex.test.touch)
rlm@232 645
rlm@283 646 (defn test-worm-touch
rlm@321 647 "Testing touch:
rlm@321 648 You will see the worm fall onto a table. There is a display which
rlm@321 649 reports the worm's sense of touch. It should change when the worm
rlm@321 650 hits the table and when you hit it with balls.
rlm@321 651
rlm@321 652 Keys:
rlm@321 653 <space> : fire ball"
rlm@283 654 ([] (test-worm-touch false))
rlm@253 655 ([record?]
rlm@253 656 (let [the-worm (doto (worm) (body!))
rlm@253 657 touch (touch! the-worm)
rlm@253 658 touch-display (view-touch)]
rlm@253 659 (world
rlm@253 660 (nodify [the-worm (floor)])
rlm@253 661 standard-debug-controls
rlm@253 662
rlm@253 663 (fn [world]
rlm@340 664 (let [timer (IsoTimer. 60)]
rlm@340 665 (.setTimer world timer)
rlm@340 666 (display-dilated-time world timer))
rlm@253 667 (if record?
rlm@253 668 (Capture/captureVideo
rlm@253 669 world
rlm@253 670 (File. "/home/r/proj/cortex/render/worm-touch/main-view/")))
rlm@253 671 (speed-up world)
rlm@253 672 (light-up-everything world))
rlm@232 673
rlm@253 674 (fn [world tpf]
rlm@253 675 (touch-display
rlm@253 676 (map #(% (.getRootNode world)) touch)
rlm@253 677 (if record?
rlm@253 678 (File. "/home/r/proj/cortex/render/worm-touch/touch/"))))))))
rlm@232 679 #+end_src
rlm@247 680
rlm@340 681 #+results: test-touch-2
rlm@340 682 : #'cortex.test.touch/test-worm-touch
rlm@340 683
rlm@253 684 ** Worm Touch Demonstration
rlm@253 685 #+begin_html
rlm@253 686 <div class="figure">
rlm@253 687 <center>
rlm@253 688 <video controls="controls" width="550">
rlm@253 689 <source src="../video/worm-touch.ogg" type="video/ogg"
rlm@253 690 preload="none" poster="../images/aurellem-1280x480.png" />
rlm@253 691 </video>
rlm@309 692 <br> <a href="http://youtu.be/RHx2wqzNVcU"> YouTube </a>
rlm@253 693 </center>
rlm@253 694 <p>The worm responds to touch.</p>
rlm@253 695 </div>
rlm@253 696 #+end_html
rlm@252 697
rlm@252 698
rlm@253 699 ** Generating the Worm Touch Video
rlm@253 700 #+name: magick5
rlm@253 701 #+begin_src clojure
rlm@253 702 (ns cortex.video.magick5
rlm@253 703 (:import java.io.File)
rlm@316 704 (:use clojure.java.shell))
rlm@253 705
rlm@253 706 (defn images [path]
rlm@253 707 (sort (rest (file-seq (File. path)))))
rlm@253 708
rlm@253 709 (def base "/home/r/proj/cortex/render/worm-touch/")
rlm@253 710
rlm@253 711 (defn pics [file]
rlm@253 712 (images (str base file)))
rlm@253 713
rlm@253 714 (defn combine-images []
rlm@253 715 (let [main-view (pics "main-view")
rlm@253 716 touch (pics "touch/0")
rlm@253 717 targets (map
rlm@253 718 #(File. (str base "out/" (format "%07d.png" %)))
rlm@253 719 (range 0 (count main-view)))]
rlm@253 720 (dorun
rlm@253 721 (pmap
rlm@253 722 (comp
rlm@253 723 (fn [[ main-view touch target]]
rlm@253 724 (println target)
rlm@253 725 (sh "convert"
rlm@253 726 main-view
rlm@253 727 touch "-geometry" "+0+0" "-composite"
rlm@253 728 target))
rlm@253 729 (fn [& args] (map #(.getCanonicalPath %) args)))
rlm@253 730 main-view touch targets))))
rlm@253 731 #+end_src
rlm@252 732
rlm@312 733 #+begin_src sh :results silent
rlm@312 734 cd ~/proj/cortex/render/worm-touch
rlm@312 735 ffmpeg -r 60 -i out/%07d.png -b:v 9000k -c:v libtheora worm-touch.ogg
rlm@312 736 #+end_src
rlm@312 737
rlm@247 738 * Headers
rlm@247 739
rlm@247 740 #+name: touch-header
rlm@247 741 #+begin_src clojure
rlm@247 742 (ns cortex.touch
rlm@247 743 "Simulate the sense of touch in jMonkeyEngine3. Enables any Geometry
rlm@247 744 to be outfitted with touch sensors with density determined by a UV
rlm@247 745 image. In this way a Geometry can know what parts of itself are
rlm@247 746 touching nearby objects. Reads specially prepared blender files to
rlm@247 747 construct this sense automatically."
rlm@247 748 {:author "Robert McIntyre"}
rlm@247 749 (:use (cortex world util sense))
rlm@247 750 (:import (com.jme3.scene Geometry Node Mesh))
rlm@247 751 (:import com.jme3.collision.CollisionResults)
rlm@247 752 (:import com.jme3.scene.VertexBuffer$Type)
rlm@247 753 (:import (com.jme3.math Triangle Vector3f Vector2f Ray Matrix4f)))
rlm@247 754 #+end_src
rlm@247 755
rlm@253 756 #+name: test-touch-header
rlm@253 757 #+begin_src clojure
rlm@253 758 (ns cortex.test.touch
rlm@253 759 (:use (cortex world util sense body touch))
rlm@253 760 (:use cortex.test.body)
rlm@340 761 (:import (com.aurellem.capture Capture IsoTimer))
rlm@253 762 (:import java.io.File)
rlm@253 763 (:import (com.jme3.math Vector3f ColorRGBA)))
rlm@253 764 #+end_src
rlm@253 765
rlm@340 766 #+results: test-touch-header
rlm@340 767 : com.jme3.math.ColorRGBA
rlm@340 768
rlm@228 769 * Source Listing
rlm@253 770 - [[../src/cortex/touch.clj][cortex.touch]]
rlm@253 771 - [[../src/cortex/test/touch.clj][cortex.test.touch]]
rlm@253 772 - [[../src/cortex/video/magick4.clj][cortex.video.magick4]]
rlm@253 773 - [[../src/cortex/video/magick5.clj][cortex.video.magick5]]
rlm@283 774 - [[../assets/Models/test-touch/touch-cube.blend][touch-cube.blend]]
rlm@253 775 #+html: <ul> <li> <a href="../org/touch.org">This org file</a> </li> </ul>
rlm@253 776 - [[http://hg.bortreb.com ][source-repository]]
rlm@253 777
rlm@254 778 * Next
rlm@332 779 So far I've implemented simulated Vision, Hearing, and
rlm@332 780 Touch, the most obvious and prominent senses that humans
rlm@332 781 have. Smell and Taste shall remain unimplemented for
rlm@332 782 now. This accounts for the "five senses" that feature so
rlm@332 783 prominently in our lives. But humans have far more than the
rlm@332 784 five main senses. There are internal chemical senses, pain
rlm@332 785 (which is *not* the same as touch), heat sensitivity, and
rlm@332 786 our sense of balance, among others. One extra sense is so
rlm@332 787 important that I must implement it to have a hope of making
rlm@332 788 creatures that can gracefully control their own bodies. It
rlm@332 789 is Proprioception, which is the sense of the location of
rlm@332 790 each body part in relation to the other body parts.
rlm@253 791
rlm@332 792 Close your eyes, and touch your nose with your right index
rlm@332 793 finger. How did you do it? You could not see your hand, and
rlm@332 794 neither your hand nor your nose could use the sense of touch
rlm@332 795 to guide the path of your hand. There are no sound cues,
rlm@332 796 and Taste and Smell certainly don't provide any help. You
rlm@332 797 know where your hand is without your other senses because of
rlm@332 798 Proprioception.
rlm@228 799
rlm@254 800 Onward to [[./proprioception.org][proprioception]]!
rlm@228 801
rlm@226 802 * COMMENT Code Generation
rlm@39 803 #+begin_src clojure :tangle ../src/cortex/touch.clj
rlm@231 804 <<touch-header>>
rlm@231 805 <<meta-data>>
rlm@231 806 <<triangles-1>>
rlm@247 807 <<triangles-2>>
rlm@231 808 <<triangles-3>>
rlm@231 809 <<triangles-4>>
rlm@231 810 <<sensors>>
rlm@231 811 <<kernel>>
rlm@231 812 <<visualization>>
rlm@0 813 #+end_src
rlm@0 814
rlm@253 815 #+begin_src clojure :tangle ../src/cortex/test/touch.clj
rlm@253 816 <<test-touch-header>>
rlm@253 817 <<test-touch-0>>
rlm@253 818 <<test-touch-1>>
rlm@253 819 <<test-touch-2>>
rlm@253 820 #+end_src
rlm@232 821
rlm@253 822 #+begin_src clojure :tangle ../src/cortex/video/magick4.clj
rlm@253 823 <<magick4>>
rlm@39 824 #+end_src
rlm@39 825
rlm@253 826 #+begin_src clojure :tangle ../src/cortex/video/magick5.clj
rlm@253 827 <<magick5>>
rlm@253 828 #+end_src