extensions [ sound ] globals [ tick-delta ;; how much we advance the tick counter this time through max-tick-delta ;; the largest tick-delta is allowed to be box-edge ;; distance of box edge from axes pressure pressure-history zero-pressure-count ;; how many zero entries are in pressure-history wall-hits-per-particle ;; average number of wall hits per particle particles-to-add new-particles ;; agentset of particles added via add-particles-middle message-shown? ;; whether we've shown the warning message yet length-horizontal-surface ;; the size of the wall surfaces that run horizontally - the top and bottom of the box length-vertical-surface ;; the size of the wall surfaces that run vertically - the left and right of the box three-speed ;; current speed of particle 3 (music addition) pressure-now ;; current pressure (music addition ] breed [ particles particle ] breed [ flashes flash ] flashes-own [birthday] particles-own [ speed mass ;; particle info wall-hits ;; # of wall hits during this clock cycle ("big tick") momentum-difference ;; used to calculate pressure from wall hits last-collision new? ;; used to build the new-particles agentset; this is ;; only ever set to true by add-particles-middle ] to startup set message-shown? false end to setup sound:stop-music ;; start music by closing previous one let tmp message-shown? ca set message-shown? tmp set-default-shape particles "circle" set-default-shape flashes "square" set particles-to-add 0 ;; box has constant size... set box-edge (max-pxcor - 1) ;;; the length of the horizontal or vertical surface of ;;; the inside of the box must exclude the two patches ;; that are the where the perpendicular walls join it, ;;; but must also add in the axes as an additional patch ;;; example: a box with a box-edge of 10, is drawn with ;;; 19 patches of wall space on the inside of the box set length-horizontal-surface ( 2 * (box-edge - 1) + 1) set length-vertical-surface ( 2 * (box-edge - 1) + 1) make-box make-particles initial-number set pressure-history [] set zero-pressure-count 0 reset-ticks set pressure-now pressure ;; setup for current pressure set three-speed [speed] of particle 3 ;; setup for current particle speed end to go if not single-particle-speed? and three-speed > 0 ;; making sure that particle speed is sung only when switch is on [ sound:stop-note "oboe" (80 - 120 / ( three-speed )) sound:stop-note "oboe" 50 ] if not pressure? and pressure > 0 ; making sure that pressure is sung only when switch is on [ sound:stop-note "recorder" ( 100 - 2000 / pressure ) sound:stop-note "recorder" 20 ] if single-particle-speed? [ ask particle 3 ;; asking particle 3 to sing, changes note when speed changes, taking care of clock = 0 [ ifelse ((abs (speed - three-speed) > 0 ) ) or (abs (speed - three-speed ) = speed ) [ sing-one-particle-speed ] [ ifelse ticks > 0 [ stop ] [ sound:start-note "oboe" (80 - 120 / ( [speed] of particle 3 )) single-particle-loudness - 10] ] ] ] if real-time? [ sing-real-time ] ;; sing the real time ticker ask particles [ set new? false ] ask particles [ bounce ] ask particles [ move ] ask particles [ check-for-collision ] add-particles-side tick-advance tick-delta if floor ticks > floor (ticks - tick-delta) [ ifelse any? particles [ set wall-hits-per-particle mean [wall-hits] of particles ] [ set wall-hits-per-particle 0 ] ask particles [ set wall-hits 0 ] calculate-pressure update-plots if model-time? [ sound:play-note "nylon string guitar" 26 83 0.1 ] ] ;; sing model time calculate-tick-length ask flashes with [ticks - birthday > 0.4] [ set pcolor yellow die ] ifelse (single-particle-speed? or single-particle-collisions? or single-particle-wall-hits? ) ;; single particle speed is traced [ ask particle 3 [ pd ] ] [ ask particle 3 [ pu ] ] fade-patches ;; if the single particle is tracing, then the trace disappears after a while end to calculate-tick-length ifelse any? particles with [speed > 0] [ set tick-delta 1 / (ceiling max [speed] of particles) ] [ set tick-delta 1 ] end ;;; Pressure is defined as the force per unit area. In this context, ;;; that means the total momentum per unit time transferred to the walls ;;; by particle hits, divided by the surface area of the walls. (Here ;;; we're in a two dimensional world, so the "surface area" of the walls ;;; is just their length.) Each wall contributes a different amount ;;; to the total pressure in the box, based on the number of collisions, the ;;; direction of each collision, and the length of the wall. Conservation of momentum ;;; in hits ensures that the difference in momentum for the particles is equal to and ;;; opposite to that for the wall. The force on each wall is the rate of change in ;;; momentum imparted to the wall, or the sum of change in momentum for each particle: ;;; F = SUM [d(mv)/dt] = SUM [m(dv/dt)] = SUM [ ma ], in a direction perpendicular to ;;; the wall surface. The pressure (P) on a given wall is the force (F) applied to that ;;; wall over its surface area. The total pressure in the box is sum of each wall's ;;; pressure contribution. to calculate-pressure ;; by summing the momentum change for each particle, ;; the wall's total momentum change is calculated set pressure 15 * sum [momentum-difference] of particles set pressure-history lput pressure pressure-history set zero-pressure-count length filter [? = 0] pressure-history ask particles [ set momentum-difference 0 ] ;; once the contribution to momentum has been calculated ;; this value is reset to zero till the next wall hit ifelse pressure? ;; when pressure changes, it sings [ sing-pressure ] [ ifelse pressure-now > 0 [ sound:stop-note "recorder" ( 100 - 2000 / pressure-now ) sound:stop-note "recorder" ( 30 ) ] [ stop ] ] end to bounce ;; particle procedure let tone heading ;; if we're not about to hit a wall (yellow patch), or if we're already on a ;; wall, we don't need to do any further checks if shade-of? yellow pcolor or not shade-of? yellow [pcolor] of patch-at dx dy [ stop ] ;; get the coordinates of the patch we'll be on if we go forward 1 let new-px round (xcor + dx) let new-py round (ycor + dy) ;; if hitting left or right wall, reflect heading around x axis if (abs new-px = box-edge) [ set heading (- heading) set wall-hits wall-hits + 1 if (wall-hits?) [ sound:play-note "celesta" tone wall-hits-loudness 0.15 ] ;; when a particle hits the wall there's sound (macro) if (single-particle-wall-hits? and who = 3) ;; when a particle hits the wall there's sound (micro) [ ask particle 3 [ pd ] sound:play-note "clavi" ( 30 + heading / 5 ) wall-hits-loudness 0.2 ] ;; if the particle is hitting a vertical wall, only the horizontal component of the speed ;; vector can change. The change in velocity for this component is 2 * the speed of the particle, ;; due to the reversing of direction of travel from the collision with the wall set momentum-difference momentum-difference + (abs (dx * 2 * mass * speed) / length-vertical-surface) ] ;; if hitting top or bottom wall, reflect heading around y axis if (abs new-py = box-edge) [ set heading (180 - heading) set wall-hits wall-hits + 1 if wall-hits? [ sound:play-note "celesta" heading single-particle-loudness 0.1 ] if (single-particle-wall-hits? and who = 3) [ ask particle 3 [ pd ] sound:play-note "clavi" ( 30 + heading / 5 ) single-particle-loudness 0.1 ] ;; if the particle is hitting a horizontal wall, only the vertical component of the speed ;; vector can change. The change in velocity for this component is 2 * the speed of the particle, ;; due to the reversing of direction of travel from the collision with the wall set momentum-difference momentum-difference + (abs (dy * 2 * mass * speed) / length-horizontal-surface) ] ask patch new-px new-py [ sprout-flashes 1 [ ht set birthday ticks set pcolor yellow - 3 ] ] end to move ;; particle procedure if patch-ahead (speed * tick-delta) != patch-here [ set last-collision nobody ] jump (speed * tick-delta) end to check-for-collision ;; particle procedure ;; Here we impose a rule that collisions only take place when there ;; are exactly two particles per patch. We do this because when the ;; student introduces new particles from the side, we want them to ;; form a uniform wavefront. ;; ;; Why do we want a uniform wavefront? Because it is actually more ;; realistic. (And also because the curriculum uses the uniform ;; wavefront to help teach the relationship between particle collisions, ;; wall hits, and pressure.) ;; ;; Why is it realistic to assume a uniform wavefront? Because in reality, ;; whether a collision takes place would depend on the actual headings ;; of the particles, not merely on their proximity. Since the particles ;; in the wavefront have identical speeds and near-identical headings, ;; in reality they would not collide. So even though the two-particles ;; rule is not itself realistic, it produces a realistic result. Also, ;; unless the number of particles is extremely large, it is very rare ;; for three or more particles to land on the same patch (for example, ;; with 400 particles it happens less than 1% of the time). So imposing ;; this additional rule should have only a negligible effect on the ;; aggregate behavior of the system. ;; ;; Why does this rule produce a uniform wavefront? The particles all ;; start out on the same patch, which means that without the only-two ;; rule, they would all start colliding with each other immediately, ;; resulting in much random variation of speeds and headings. With ;; the only-two rule, they are prevented from colliding with each other ;; until they have spread out a lot. (And in fact, if you observe ;; the wavefront closely, you will see that it is not completely smooth, ;; because some collisions eventually do start occurring when it thins out while fanning.) if count other particles-here = 1 [ ;; the following conditions are imposed on collision candidates: ;; 1. they must have a lower who number than my own, because collision ;; code is asymmetrical: it must always happen from the point of view ;; of just one particle. ;; 2. they must not be the same particle that we last collided with on ;; this patch, so that we have a chance to leave the patch after we've ;; collided with someone. let candidate one-of other particles-here with [who < [who] of myself and myself != last-collision] ;; we also only collide if one of us has non-zero speed. It's useless ;; (and incorrect, actually) for two particles with zero speed to collide. if (candidate != nobody) and (speed > 0 or [speed] of candidate > 0) [ collide-with candidate set last-collision candidate ask candidate [ set last-collision myself ] if collisions? ;; make a sound when there's a collision that is a function of the sum of their speeds (macro) [ sound:play-note "telephone ring" 2 * ([speed] of self + [speed] of candidate) collisions-loudness 0.15 ] if (single-particle-collisions? and ( who = 3 or [who] of candidate = 3 )) ;; make a sound when there's a collision that is a function of the sum of their speeds (micro) [ ask particle 3 [ pd ] sound:play-note "glockenspiel" 69 single-particle-loudness + 40 0.2 ] ] ] end ;; implements a collision with another particle. ;; ;; THIS IS THE HEART OF THE PARTICLE SIMULATION, AND YOU ARE STRONGLY ADVISED ;; NOT TO CHANGE IT UNLESS YOU REALLY UNDERSTAND WHAT YOU'RE DOING! ;; ;; The two particles colliding are self and other-particle, and while the ;; collision is performed from the point of view of self, both particles are ;; modified to reflect its effects. This is somewhat complicated, so I'll ;; give a general outline here: ;; 1. Do initial setup, and determine the heading between particle centers ;; (call it theta). ;; 2. Convert the representation of the velocity of each particle from ;; speed/heading to a theta-based vector whose first component is the ;; particle's speed along theta, and whose second component is the speed ;; perpendicular to theta. ;; 3. Modify the velocity vectors to reflect the effects of the collision. ;; This involves: ;; a. computing the velocity of the center of mass of the whole system ;; along direction theta ;; b. updating the along-theta components of the two velocity vectors. ;; 4. Convert from the theta-based vector representation of velocity back to ;; the usual speed/heading representation for each particle. ;; 5. Perform final cleanup and update derived quantities. to collide-with [ other-particle ] ;; particle procedure ;; local copies of other-particle's relevant quantities ;mass2 speed2 heading2 ;; quantities used in the collision itself ;theta ;; heading of vector from my center to the center of other-particle. ;v1t ;; velocity of self along direction theta ;v1l ;; velocity of self perpendicular to theta ;v2t v2l ;; velocity of other-particle, represented in the same way ;vcm ;; velocity of the center of mass of the colliding particles, ;; along direction theta ;;; PHASE 1: initial setup ;; for convenience, grab some quantities from other-particle let mass2 [mass] of other-particle let speed2 [speed] of other-particle let heading2 [heading] of other-particle ;; since particles are modeled as zero-size points, theta isn't meaningfully ;; defined. we can assign it randomly without affecting the model's outcome. let theta (random-float 360) ;;; PHASE 2: convert velocities to theta-based vector representation ;; now convert my velocity from speed/heading representation to components ;; along theta and perpendicular to theta let v1t (speed * cos (theta - heading)) let v1l (speed * sin (theta - heading)) ;; do the same for other-particle let v2t (speed2 * cos (theta - heading2)) let v2l (speed2 * sin (theta - heading2)) ;;; PHASE 3: manipulate vectors to implement collision ;; compute the velocity of the system's center of mass along theta let vcm (((mass * v1t) + (mass2 * v2t)) / (mass + mass2) ) ;; now compute the new velocity for each particle along direction theta. ;; velocity perpendicular to theta is unaffected by a collision along theta, ;; so the next two lines actually implement the collision itself, in the ;; sense that the effects of the collision are exactly the following changes ;; in particle velocity. set v1t (2 * vcm - v1t) set v2t (2 * vcm - v2t) ;;; PHASE 4: convert back to normal speed/heading ;; now convert my velocity vector into my new speed and heading set speed sqrt ((v1t * v1t) + (v1l * v1l)) ;; if the magnitude of the velocity vector is 0, atan is undefined. but ;; speed will be 0, so heading is irrelevant anyway. therefore, in that ;; case we'll just leave it unmodified. if v1l != 0 or v1t != 0 [ set heading (theta - (atan v1l v1t)) ] ;; and do the same for other-particle ask other-particle [ set speed sqrt ((v2t * v2t) + (v2l * v2l)) if v2l != 0 or v2t != 0 [ set heading (theta - (atan v2l v2t)) ] ] ;; PHASE 5: final updates ;; now recolor, since color is based on quantities that may have changed recolor ask other-particle [ recolor ] end to recolor ;; particle procedure ifelse speed < (0.5 * 10) [ set color blue ] [ ifelse speed > (1.5 * 10) [ set color red ] [ set color green ] ] end ;;; ;;; drawing procedures ;;; ;; draws the box to make-box ask patches with [ ((abs pxcor = box-edge) and (abs pycor <= box-edge)) or ((abs pycor = box-edge) and (abs pxcor <= box-edge)) ] [ set pcolor yellow ] ask patches with [pycor = 0 and pxcor < (1 - box-edge)] [ set pcolor yellow - 5 ;; trick the bounce code so particles don't go into the inlet ask patch-at 0 1 [ set pcolor yellow ] ask patch-at 0 -1 [ set pcolor yellow ] ] end ;; creates initial particles to make-particles [number] create-particles number [ setup-particle set speed random-float 20 random-position recolor ] calculate-tick-length end ;; adds particles from the left to add-particles-side if particles-to-add > 0 [ create-particles particles-to-add [ setup-particle setxy (- box-edge) 0 set heading 90 ;; east rt 45 - random-float 90 recolor ] if announce-add-particles? [ sound:play-note "tubular bells" 59 90 0.3 ] ;; announce when particles are added set particles-to-add 0 calculate-tick-length ] end ;; called by student from command center; ;; adds particles in middle to add-particles-middle [n] create-particles n [ setup-particle set new? true recolor ] ;; add the new particles to an agentset, so they ;; are accessible to the student from the command ;; center, e.g. "ask new-particles [ ... ]" set new-particles particles with [new?] calculate-tick-length end to setup-particle ;; particle procedure set new? false set speed 10 set mass 1.0 set last-collision nobody set wall-hits 0 set momentum-difference 0 end ;; place particle at random location inside the box. to random-position ;; particle procedure setxy ((1 - box-edge) + random-float ((2 * box-edge) - 2)) ((1 - box-edge) + random-float ((2 * box-edge) - 2)) end to-report last-n [n the-list] ifelse n >= length the-list [ report the-list ] [ report last-n n butfirst the-list ] end to fade-patches let trace-patches patches with [ shade-of? pcolor red or shade-of? pcolor blue or shade-of? pcolor green ] if any? trace-patches [ ask trace-patches [ set pcolor ( pcolor - 0.05 ) if (pcolor mod 10 < 1) [ set pcolor black ] ] ] end to sing-one-particle-speed ;; procedure for listening to one particle's speed - tone is a function of speed ifelse single-particle-speed? [ ifelse (three-speed > 3) [ sound:stop-note "oboe" (80 - 120 / ( three-speed )) sound:stop-note "oboe" 50 sound:start-note "oboe" (80 - 120 / ( [speed] of particle 3 )) single-particle-loudness ] [ sound:stop-note "oboe" (80 - 120 / ( three-speed )) sound:stop-note "oboe" 50 sound:start-note "oboe" 50 single-particle-loudness + 20 ] set three-speed [speed] of particle 3 ] [ ifelse (three-speed > 3) [ sound:stop-note "oboe" (80 - 120 / ( three-speed ))] [ sound:stop-note "oboe" 50 ] ] end to sing-real-time ;; real time is drummed at a regular interval every real-time-pacer [ sound:play-note "sci-fi" 30 60 0.3 ] end to sing-pressure ;; pressure is sung by a recorder with the tone a function of pressure if ( abs ( pressure-now - pressure ) > 0 and pressure-now != 0) [ sound:stop-note "recorder" ( 100 - 2000 / pressure-now ) sound:stop-note "recorder" ( 30 ) ] set pressure-now pressure ifelse (pressure > 30 ) [ sound:start-note "recorder" ( 100 - 2000 / pressure ) pressure-loudness ] [ sound:start-note "recorder" ( 30 ) pressure-loudness + 10 ] end ; Copyright 2004 Uri Wilensky. ; See Info tab for full copyright and license. @#$#@#$#@ GRAPHICS-WINDOW 212 10 490 309 33 33 4.0 1 10 1 1 1 0 0 0 1 -33 33 -33 33 0 0 1 ticks 30.0 BUTTON 125 44 211 77 go/stop go T 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 125 11 211 44 NIL setup NIL 1 T OBSERVER NIL NIL NIL NIL 1 PLOT 491 155 694 309 Number vs. Time time number 0.0 20.0 0.0 200.0 true false "set-plot-y-range 0 initial-number + 1" "" PENS "default" 1.0 0 -16777216 true "" "plotxy ticks (count particles)" SLIDER 0 78 124 111 number-to-add number-to-add 0 100 25 1 1 NIL HORIZONTAL BUTTON 125 78 211 111 add particles set particles-to-add\n particles-to-add +\n number-to-add NIL 1 T OBSERVER NIL NIL NIL NIL 1 SLIDER 0 44 124 77 initial-number initial-number 0 100 25 1 1 NIL HORIZONTAL MONITOR 1 112 99 157 Number count particles 0 1 11 PLOT 492 10 695 155 Pressure vs. Time time pressure 0.0 20.0 0.0 100.0 true false "" "" PENS "default" 1.0 0 -16777216 true "" "if length pressure-history > 0\n[\n ;; pressure plot is 'smoothed' by averaging 3 sequential values, only if switch is set this way\n ifelse avg-plot-pressure? \n [ plotxy ticks (mean last-n 3 pressure-history) ]\n [ plotxy ticks pressure ]\n]" MONITOR 100 113 209 158 pressure pressure 0 1 11 SWITCH 228 463 341 496 collisions? collisions? 1 1 -1000 SWITCH 229 428 341 461 wall-hits? wall-hits? 1 1 -1000 SWITCH 17 359 181 392 model-time? model-time? 1 1 -1000 SWITCH 17 394 182 427 real-time? real-time? 1 1 -1000 SWITCH 507 428 696 461 single-particle-speed? single-particle-speed? 0 1 -1000 SWITCH 508 463 696 496 single-particle-wall-hits? single-particle-wall-hits? 0 1 -1000 SWITCH 508 497 695 530 single-particle-collisions? single-particle-collisions? 0 1 -1000 SLIDER 16 430 183 463 real-time-pacer real-time-pacer 0.5 5 1.325 0.025 1 sec HORIZONTAL SWITCH 10 273 200 306 announce-add-particles? announce-add-particles? 1 1 -1000 TEXTBOX 538 322 654 340 Listen to one particle 11 0.0 0 SWITCH 229 394 341 427 pressure? pressure? 1 1 -1000 TEXTBOX 280 322 416 340 Listen to all the particles 11 0.0 0 TEXTBOX 38 321 128 339 Time in a model 11 0.0 0 SLIDER 342 463 469 496 collisions-loudness collisions-loudness 0 100 30 5 1 NIL HORIZONTAL SLIDER 343 428 468 461 wall-hits-loudness wall-hits-loudness 0 100 30 5 1 NIL HORIZONTAL SLIDER 343 393 469 426 pressure-loudness pressure-loudness 0 120 60 5 1 NIL HORIZONTAL BUTTON 33 225 98 258 all on set real-time? true \nset model-time? true \nset pressure? true \nset wall-hits? true \nset collisions? true \nset single-particle-speed? true \nset single-particle-collisions? true\nset single-particle-wall-hits? true \nset announce-add-particles? true NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 99 225 165 258 all off sound:stop-music\nset collisions? false\nset single-particle-speed? false \nset single-particle-collisions? false\nset single-particle-wall-hits? false\nset announce-add-particles? false\nset model-time? false\nset real-time? false\nset pressure? false\nset wall-hits? false NIL 1 T OBSERVER NIL NIL NIL NIL 1 SLIDER 507 394 696 427 single-particle-loudness single-particle-loudness 0 80 30 5 1 NIL HORIZONTAL MONITOR 1 163 210 208 single speed [speed] of particle 3 1 1 11 SWITCH 70 507 235 540 avg-plot-pressure? avg-plot-pressure? 1 1 -1000 BUTTON 252 353 341 386 group on set pressure? true set wall-hits? true set collisions? true NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 342 353 432 386 group off set pressure? false set wall-hits? false set collisions? false NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 515 353 603 386 single on set single-particle-speed? true set single-particle-collisions? true set single-particle-wall-hits? true NIL 1 T OBSERVER NIL NIL NIL NIL 1 BUTTON 604 353 693 386 single off set single-particle-speed? false \nset single-particle-collisions? false \nset single-particle-wall-hits? false NIL 1 T OBSERVER NIL NIL NIL NIL 1 @#$#@#$#@ ## WHAT IS IT? This model is included here in "Code Examples" as an example of taking an existing model and adding sound to it. It is based on the GasLab models, in the Chemistry & Physics section of the Models Library. @#$#@#$#@ default true 0 Polygon -7500403 true true 150 5 40 250 150 205 260 250 airplane true 0 Polygon -7500403 true true 150 0 135 15 120 60 120 105 15 165 15 195 120 180 135 240 105 270 120 285 150 270 180 285 210 270 165 240 180 180 285 195 285 165 180 105 180 60 165 15 arrow true 0 Polygon -7500403 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150 box false 0 Polygon -7500403 true true 150 285 285 225 285 75 150 135 Polygon -7500403 true true 150 135 15 75 150 15 285 75 Polygon -7500403 true true 15 75 15 225 150 285 150 135 Line -16777216 false 150 285 150 135 Line -16777216 false 150 135 15 75 Line -16777216 false 150 135 285 75 bug true 0 Circle -7500403 true true 96 182 108 Circle -7500403 true true 110 127 80 Circle -7500403 true true 110 75 80 Line -7500403 true 150 100 80 30 Line -7500403 true 150 100 220 30 butterfly true 0 Polygon -7500403 true true 150 165 209 199 225 225 225 255 195 270 165 255 150 240 Polygon -7500403 true true 150 165 89 198 75 225 75 255 105 270 135 255 150 240 Polygon -7500403 true true 139 148 100 105 55 90 25 90 10 105 10 135 25 180 40 195 85 194 139 163 Polygon -7500403 true true 162 150 200 105 245 90 275 90 290 105 290 135 275 180 260 195 215 195 162 165 Polygon -16777216 true false 150 255 135 225 120 150 135 120 150 105 165 120 180 150 165 225 Circle -16777216 true false 135 90 30 Line -16777216 false 150 105 195 60 Line -16777216 false 150 105 105 60 car false 0 Polygon -7500403 true true 300 180 279 164 261 144 240 135 226 132 213 106 203 84 185 63 159 50 135 50 75 60 0 150 0 165 0 225 300 225 300 180 Circle -16777216 true false 180 180 90 Circle -16777216 true false 30 180 90 Polygon -16777216 true false 162 80 132 78 134 135 209 135 194 105 189 96 180 89 Circle -7500403 true true 47 195 58 Circle -7500403 true true 195 195 58 circle false 0 Circle -7500403 true true 0 0 300 circle 2 false 0 Circle -7500403 true true 0 0 300 Circle -16777216 true false 30 30 240 clock true 0 Circle -7500403 true true 30 30 240 Polygon -16777216 true false 150 31 128 75 143 75 143 150 158 150 158 75 173 75 Circle -16777216 true false 135 135 30 cow false 0 Polygon -7500403 true true 200 193 197 249 179 249 177 196 166 187 140 189 93 191 78 179 72 211 49 209 48 181 37 149 25 120 25 89 45 72 103 84 179 75 198 76 252 64 272 81 293 103 285 121 255 121 242 118 224 167 Polygon -7500403 true true 73 210 86 251 62 249 48 208 Polygon -7500403 true true 25 114 16 195 9 204 23 213 25 200 39 123 cylinder false 0 Circle -7500403 true true 0 0 300 dot false 0 Circle -7500403 true true 90 90 120 face happy false 0 Circle -7500403 true true 8 8 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Polygon -16777216 true false 150 255 90 239 62 213 47 191 67 179 90 203 109 218 150 225 192 218 210 203 227 181 251 194 236 217 212 240 face neutral false 0 Circle -7500403 true true 8 7 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Rectangle -16777216 true false 60 195 240 225 face sad false 0 Circle -7500403 true true 8 8 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Polygon -16777216 true false 150 168 90 184 62 210 47 232 67 244 90 220 109 205 150 198 192 205 210 220 227 242 251 229 236 206 212 183 fish false 0 Polygon -1 true false 44 131 21 87 15 86 0 120 15 150 0 180 13 214 20 212 45 166 Polygon -1 true false 135 195 119 235 95 218 76 210 46 204 60 165 Polygon -1 true false 75 45 83 77 71 103 86 114 166 78 135 60 Polygon -7500403 true true 30 136 151 77 226 81 280 119 292 146 292 160 287 170 270 195 195 210 151 212 30 166 Circle -16777216 true false 215 106 30 flag false 0 Rectangle -7500403 true true 60 15 75 300 Polygon -7500403 true true 90 150 270 90 90 30 Line -7500403 true 75 135 90 135 Line -7500403 true 75 45 90 45 flower false 0 Polygon -10899396 true false 135 120 165 165 180 210 180 240 150 300 165 300 195 240 195 195 165 135 Circle -7500403 true true 85 132 38 Circle -7500403 true true 130 147 38 Circle -7500403 true true 192 85 38 Circle -7500403 true true 85 40 38 Circle -7500403 true true 177 40 38 Circle -7500403 true true 177 132 38 Circle -7500403 true true 70 85 38 Circle -7500403 true true 130 25 38 Circle -7500403 true true 96 51 108 Circle -16777216 true false 113 68 74 Polygon -10899396 true false 189 233 219 188 249 173 279 188 234 218 Polygon -10899396 true false 180 255 150 210 105 210 75 240 135 240 house false 0 Rectangle -7500403 true true 45 120 255 285 Rectangle -16777216 true false 120 210 180 285 Polygon -7500403 true true 15 120 150 15 285 120 Line -16777216 false 30 120 270 120 leaf false 0 Polygon -7500403 true true 150 210 135 195 120 210 60 210 30 195 60 180 60 165 15 135 30 120 15 105 40 104 45 90 60 90 90 105 105 120 120 120 105 60 120 60 135 30 150 15 165 30 180 60 195 60 180 120 195 120 210 105 240 90 255 90 263 104 285 105 270 120 285 135 240 165 240 180 270 195 240 210 180 210 165 195 Polygon -7500403 true true 135 195 135 240 120 255 105 255 105 285 135 285 165 240 165 195 line true 0 Line -7500403 true 150 0 150 300 line half true 0 Line -7500403 true 150 0 150 150 pentagon false 0 Polygon -7500403 true true 150 15 15 120 60 285 240 285 285 120 person false 0 Circle -7500403 true true 110 5 80 Polygon -7500403 true true 105 90 120 195 90 285 105 300 135 300 150 225 165 300 195 300 210 285 180 195 195 90 Rectangle -7500403 true true 127 79 172 94 Polygon -7500403 true true 195 90 240 150 225 180 165 105 Polygon -7500403 true true 105 90 60 150 75 180 135 105 plant false 0 Rectangle -7500403 true true 135 90 165 300 Polygon -7500403 true true 135 255 90 210 45 195 75 255 135 285 Polygon -7500403 true true 165 255 210 210 255 195 225 255 165 285 Polygon -7500403 true true 135 180 90 135 45 120 75 180 135 210 Polygon -7500403 true true 165 180 165 210 225 180 255 120 210 135 Polygon -7500403 true true 135 105 90 60 45 45 75 105 135 135 Polygon -7500403 true true 165 105 165 135 225 105 255 45 210 60 Polygon -7500403 true true 135 90 120 45 150 15 180 45 165 90 square false 0 Rectangle -7500403 true true 30 30 270 270 square 2 false 0 Rectangle -7500403 true true 30 30 270 270 Rectangle -16777216 true false 60 60 240 240 star false 0 Polygon -7500403 true true 151 1 185 108 298 108 207 175 242 282 151 216 59 282 94 175 3 108 116 108 target false 0 Circle -7500403 true true 0 0 300 Circle -16777216 true false 30 30 240 Circle -7500403 true true 60 60 180 Circle -16777216 true false 90 90 120 Circle -7500403 true true 120 120 60 tree false 0 Circle -7500403 true true 118 3 94 Rectangle -6459832 true false 120 195 180 300 Circle -7500403 true true 65 21 108 Circle -7500403 true true 116 41 127 Circle -7500403 true true 45 90 120 Circle -7500403 true true 104 74 152 triangle false 0 Polygon -7500403 true true 150 30 15 255 285 255 triangle 2 false 0 Polygon -7500403 true true 150 30 15 255 285 255 Polygon -16777216 true 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