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comparison org/touch.org @ 238:3fa49ff1649a

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going to recode touch.org to make it look better
author Robert McIntyre <rlm@mit.edu>
date Sun, 12 Feb 2012 12:10:51 -0700
parents 712bd7e5b148
children 78a640e3bc55
comparison
equal deleted inserted replaced
237:02b2e6f3fb43 238:3fa49ff1649a
48 and length of the "hairs" which will constitute its sense of 48 and length of the "hairs" which will constitute its sense of
49 touch. This image path is stored under the "touch" key. The image 49 touch. This image path is stored under the "touch" key. The image
50 itself is grayscale, with black meaning a hair length of 0 (no hair is 50 itself is grayscale, with black meaning a hair length of 0 (no hair is
51 present) and white meaning a hair length of =scale=, which is a float 51 present) and white meaning a hair length of =scale=, which is a float
52 stored under the key "scale". If the pixel is gray then the resultant 52 stored under the key "scale". If the pixel is gray then the resultant
53 hair length is linearly interpolated between 0 and =scale=. 53 hair length is linearly interpolated between 0 and =scale=. I call
54 these "hairs" /feelers/.
54 55
55 #+name: meta-data 56 #+name: meta-data
56 #+begin_src clojure 57 #+begin_src clojure
57 (defn tactile-sensor-profile 58 (defn tactile-sensor-profile
58 "Return the touch-sensor distribution image in BufferedImage format, 59 "Return the touch-sensor distribution image in BufferedImage format,
83 xyz-triangles 84 xyz-triangles
84 conversions (map triangles->affine-transform pixel-triangles 85 conversions (map triangles->affine-transform pixel-triangles
85 xyz-triangles) 86 xyz-triangles)
86 87
87 #+end_src 88 #+end_src
89
90
91 =(touch-kernel)= generates the functions which implement the sense of
92 touch for a creature. These functions must do 6 things to obtain touch
93 data.
94
95 - Get the tactile profile image and scale paramaters which describe
96 the layout of feelers along the object's surface.
97 - Get the lengths of each feeler by analyzing the color of the
98 pixels in the tactile profile image.
99 - Find the triangles which make up the mesh in pixel-space and in
100 world-space.
101 - Find the coordinates of each pixel in world-space. These
102 coordinates are the origins of the feelers.
103 - Calculate the normals of the triangles in world space, and add
104 them to each of the origins of the feelers. These are the
105 normalized coordinates of the tips of the feelers.
106 - Generate some sort of topology for the sensors.
88 107
89 #+name: kernel 108 #+name: kernel
90 #+begin_src clojure 109 #+begin_src clojure
91 (in-ns 'cortex.touch) 110 (in-ns 'cortex.touch)
92 111
171 (map touch-kernel 190 (map touch-kernel
172 (filter #(isa? (class %) Geometry) 191 (filter #(isa? (class %) Geometry)
173 (node-seq creature))))) 192 (node-seq creature)))))
174 #+end_src 193 #+end_src
175 194
195 * Sensor Related Functions
196
197 These functions analyze the touch-sensor-profile image convert the
198 location of each touch sensor from pixel coordinates to UV-coordinates
199 and XYZ-coordinates.
200
201 #+name: sensors
202 #+begin_src clojure
203 (defn sensors-in-triangle
204 "Locate the touch sensors in the triangle, returning a map of their
205 UV and geometry-relative coordinates."
206 [image mesh tri-index]
207 (let [width (.getWidth image)
208 height (.getHeight image)
209 UV-vertex-coords (triangle-UV-coord mesh width height tri-index)
210 bounds (convex-bounds UV-vertex-coords)
211
212 cutout-triangle (points->triangle UV-vertex-coords)
213 UV-sensor-coords
214 (filter (comp (partial inside-triangle? cutout-triangle)
215 (fn [[u v]] (Vector3f. u v 0)))
216 (white-coordinates image bounds))
217 UV->geometry (triangle-transformation
218 cutout-triangle
219 (mesh-triangle mesh tri-index))
220 geometry-sensor-coords
221 (map (fn [[u v]] (.mult UV->geometry (Vector3f. u v 0)))
222 UV-sensor-coords)]
223 {:UV UV-sensor-coords :geometry geometry-sensor-coords}))
224
225 (defn-memo locate-feelers
226 "Search the geometry's tactile UV profile for touch sensors,
227 returning their positions in geometry-relative coordinates."
228 [#^Geometry geo]
229 (let [mesh (.getMesh geo)
230 num-triangles (.getTriangleCount mesh)]
231 (if-let [image (tactile-sensor-profile geo)]
232 (map
233 (partial sensors-in-triangle image mesh)
234 (range num-triangles))
235 (repeat (.getTriangleCount mesh) {:UV nil :geometry nil}))))
236
237 (defn-memo touch-topology
238 "Return a sequence of vectors of the form [x y] describing the
239 \"topology\" of the tactile sensors. Points that are close together
240 in the touch-topology are generally close together in the simulation."
241 [#^Gemoetry geo]
242 (vec (collapse (reduce concat (map :UV (locate-feelers geo))))))
243
244 (defn-memo feeler-coordinates
245 "The location of the touch sensors in world-space coordinates."
246 [#^Geometry geo]
247 (vec (map :geometry (locate-feelers geo))))
248 #+end_src
249
250
251
252
176 * Visualizing Touch 253 * Visualizing Touch
177 #+name: visualization 254 #+name: visualization
178 #+begin_src clojure 255 #+begin_src clojure
179 (in-ns 'cortex.touch) 256 (in-ns 'cortex.touch)
180 257
391 (same-side? vert-2 vert-3 vert-1 p) 468 (same-side? vert-2 vert-3 vert-1 p)
392 (same-side? vert-3 vert-1 vert-2 p)))) 469 (same-side? vert-3 vert-1 vert-2 p))))
393 #+end_src 470 #+end_src
394 471
395 472
396 * Sensor Related Functions
397
398 These functions analyze the touch-sensor-profile image convert the
399 location of each touch sensor from pixel coordinates to UV-coordinates
400 and XYZ-coordinates.
401
402 #+name: sensors
403 #+begin_src clojure
404 (defn sensors-in-triangle
405 "Locate the touch sensors in the triangle, returning a map of their
406 UV and geometry-relative coordinates."
407 [image mesh tri-index]
408 (let [width (.getWidth image)
409 height (.getHeight image)
410 UV-vertex-coords (triangle-UV-coord mesh width height tri-index)
411 bounds (convex-bounds UV-vertex-coords)
412
413 cutout-triangle (points->triangle UV-vertex-coords)
414 UV-sensor-coords
415 (filter (comp (partial inside-triangle? cutout-triangle)
416 (fn [[u v]] (Vector3f. u v 0)))
417 (white-coordinates image bounds))
418 UV->geometry (triangle-transformation
419 cutout-triangle
420 (mesh-triangle mesh tri-index))
421 geometry-sensor-coords
422 (map (fn [[u v]] (.mult UV->geometry (Vector3f. u v 0)))
423 UV-sensor-coords)]
424 {:UV UV-sensor-coords :geometry geometry-sensor-coords}))
425
426 (defn-memo locate-feelers
427 "Search the geometry's tactile UV profile for touch sensors,
428 returning their positions in geometry-relative coordinates."
429 [#^Geometry geo]
430 (let [mesh (.getMesh geo)
431 num-triangles (.getTriangleCount mesh)]
432 (if-let [image (tactile-sensor-profile geo)]
433 (map
434 (partial sensors-in-triangle image mesh)
435 (range num-triangles))
436 (repeat (.getTriangleCount mesh) {:UV nil :geometry nil}))))
437
438 (defn-memo touch-topology
439 "Return a sequence of vectors of the form [x y] describing the
440 \"topology\" of the tactile sensors. Points that are close together
441 in the touch-topology are generally close together in the simulation."
442 [#^Gemoetry geo]
443 (vec (collapse (reduce concat (map :UV (locate-feelers geo))))))
444
445 (defn-memo feeler-coordinates
446 "The location of the touch sensors in world-space coordinates."
447 [#^Geometry geo]
448 (vec (map :geometry (locate-feelers geo))))
449 #+end_src
450
451 * Physics Collision Objects 473 * Physics Collision Objects
452 474
453 The "hairs" are actually =Rays= which extend from a point on a 475 The "hairs" are actually =Rays= which extend from a point on a
454 =Triangle= in the =Mesh= normal to the =Triangle's= surface. 476 =Triangle= in the =Mesh= normal to the =Triangle's= surface.
455 477