Marching squares: Difference between revisions

Line 29:

<pre>

points = [(3, 4), (4, 3), (4, 2), (4, 1), (3, 0), (2, 1), (2, 1), (1, 2), (1, 3), (2, 4), (3, 4)]

</pre>

=={{header|Phix}}==

with javascript_semantics

enum E, N, W, S

constant dx = {1,0,-1,0},

dy = {0,-1,0,1}

function identifyPerimeter(sequence data)

integer height = length(data),

width = length(data[1])

for x=1 to width do

for y=1 to height do

if data[y][x]!=0 then

string directions = ""

integer cx = x, cy = y, direction, previous = null;

while true do

integer mask = 0

for dxyb in {{0,0,1},{1,0,2},{0,1,4},{1,1,8}} do

integer {dx,dy,b} = dxyb,

mx = cx+dx,

my = cy+dy

if mx>1 and my>1 and data[my-1,mx-1]!=0 then

mask += b

end if

end for

switch mask do

case 1,5,13 : direction = N

case 2,3,7 : direction = E

case 4,12,14: direction = W

case 8,10,11: direction = S

case 6: direction = iff(previous == N ? W : E)

case 9: direction = iff(previous == E ? N : S)

end switch

directions &= "ENWS"[direction]

cx += dx[direction]

cy += dy[direction]

previous = direction

if cx=x and cy=y then exit end if

end while

return {x-1, -(y-1), directions}

end if

end for

return {0,0,"Not found!"}

end function

constant example = {{0, 0, 0, 0, 0},

{0, 0, 0, 0, 0},

{0, 0, 1, 1, 0},

{0, 0, 0, 1, 0},

{0, 0, 0, 0, 0}}

printf(1,"X: %d, Y: %d, Path: %s\n",identifyPerimeter(example))

<pre>

X: 2, Y: -2, Path: SSESENNNWW

</pre>

@@ Line 29: / Line 29: @@
 <pre>
 points = [(3, 4), (4, 3), (4, 2), (4, 1), (3, 0), (2, 1), (2, 1), (1, 2), (1, 3), (2, 4), (3, 4)]
+</pre>
+=={{header|Phix}}==
+<!--<lang Phix>(phixonline)-->
+ <span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
+ <span style="color: #008080;">enum</span> <span style="color: #000000;">E</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">N</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">W</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">S</span>
+ <span style="color: #008080;">constant</span> <span style="color: #000000;">dx</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">},</span>
+          <span style="color: #000000;">dy</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">}</span>
+ <span style="color: #008080;">function</span> <span style="color: #000000;">identifyPerimeter</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">data</span><span style="color: #0000FF;">)</span>
+     <span style="color: #004080;">integer</span> <span style="color: #000000;">height</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">data</span><span style="color: #0000FF;">),</span>
+              <span style="color: #000000;">width</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">data</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">])</span>
+     <span style="color: #008080;">for</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">width</span> <span style="color: #008080;">do</span>
+         <span style="color: #008080;">for</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">height</span> <span style="color: #008080;">do</span>
+             <span style="color: #008080;">if</span> <span style="color: #000000;">data</span><span style="color: #0000FF;">[</span><span style="color: #000000;">y</span><span style="color: #0000FF;">][</span><span style="color: #000000;">x</span><span style="color: #0000FF;">]!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
+                 <span style="color: #004080;">string</span> <span style="color: #000000;">directions</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
+                 <span style="color: #004080;">integer</span> <span style="color: #000000;">cx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">cy</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">direction</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">previous</span> <span style="color: #0000FF;">=</span> <span style="color: #004600;">null</span><span style="color: #0000FF;">;</span>
+                 <span style="color: #008080;">while</span> <span style="color: #004600;">true</span> <span style="color: #008080;">do</span>
+                     <span style="color: #004080;">integer</span> <span style="color: #000000;">mask</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
+                     <span style="color: #008080;">for</span> <span style="color: #000000;">dxyb</span> <span style="color: #008080;">in</span> <span style="color: #0000FF;">{{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">2</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">4</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">8</span><span style="color: #0000FF;">}}</span> <span style="color: #008080;">do</span>
+                         <span style="color: #004080;">integer</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">dx</span><span style="color: #0000FF;">,</span><span style="color: #000000;">dy</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">dxyb</span><span style="color: #0000FF;">,</span>
+                                 <span style="color: #000000;">mx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cx</span><span style="color: #0000FF;">+</span><span style="color: #000000;">dx</span><span style="color: #0000FF;">,</span>
+                                 <span style="color: #000000;">my</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">dy</span>
+                         <span style="color: #008080;">if</span> <span style="color: #000000;">mx</span><span style="color: #0000FF;">></span><span style="color: #000000;">1</span> <span style="color: #008080;">and</span> <span style="color: #000000;">my</span><span style="color: #0000FF;">></span><span style="color: #000000;">1</span> <span style="color: #008080;">and</span> <span style="color: #000000;">data</span><span style="color: #0000FF;">[</span><span style="color: #000000;">my</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">mx</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
+                             <span style="color: #000000;">mask</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">b</span>
+                         <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+                     <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+                     <span style="color: #008080;">switch</span> <span style="color: #000000;">mask</span> <span style="color: #008080;">do</span>
+                         <span style="color: #008080;">case</span>  <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">5</span><span style="color: #0000FF;">,</span><span style="color: #000000;">13</span> <span style="color: #0000FF;">:</span> <span style="color: #000000;">direction</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">N</span>
+                         <span style="color: #008080;">case</span>  <span style="color: #000000;">2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3</span><span style="color: #0000FF;">,</span><span style="color: #000000;">7</span>  <span style="color: #0000FF;">:</span> <span style="color: #000000;">direction</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">E</span>
+                         <span style="color: #008080;">case</span>  <span style="color: #000000;">4</span><span style="color: #0000FF;">,</span><span style="color: #000000;">12</span><span style="color: #0000FF;">,</span><span style="color: #000000;">14</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">direction</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">W</span>
+                         <span style="color: #008080;">case</span>  <span style="color: #000000;">8</span><span style="color: #0000FF;">,</span><span style="color: #000000;">10</span><span style="color: #0000FF;">,</span><span style="color: #000000;">11</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">direction</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">S</span>
+                         <span style="color: #008080;">case</span>  <span style="color: #000000;">6</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">direction</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">previous</span> <span style="color: #0000FF;">==</span> <span style="color: #000000;">N</span> <span style="color: #0000FF;">?</span> <span style="color: #000000;">W</span> <span style="color: #0000FF;">:</span> <span style="color: #000000;">E</span><span style="color: #0000FF;">)</span>
+                         <span style="color: #008080;">case</span>  <span style="color: #000000;">9</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">direction</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">previous</span> <span style="color: #0000FF;">==</span> <span style="color: #000000;">E</span> <span style="color: #0000FF;">?</span> <span style="color: #000000;">N</span> <span style="color: #0000FF;">:</span> <span style="color: #000000;">S</span><span style="color: #0000FF;">)</span>
+                     <span style="color: #008080;">end</span> <span style="color: #008080;">switch</span>
+                     <span style="color: #000000;">directions</span> <span style="color: #0000FF;">&=</span> <span style="color: #008000;">"ENWS"</span><span style="color: #0000FF;">[</span><span style="color: #000000;">direction</span><span style="color: #0000FF;">]</span>
+                     <span style="color: #000000;">cx</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">dx</span><span style="color: #0000FF;">[</span><span style="color: #000000;">direction</span><span style="color: #0000FF;">]</span>
+                     <span style="color: #000000;">cy</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">dy</span><span style="color: #0000FF;">[</span><span style="color: #000000;">direction</span><span style="color: #0000FF;">]</span>
+                     <span style="color: #000000;">previous</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">direction</span>
+                     <span style="color: #008080;">if</span> <span style="color: #000000;">cx</span><span style="color: #0000FF;">=</span><span style="color: #000000;">x</span> <span style="color: #008080;">and</span> <span style="color: #000000;">cy</span><span style="color: #0000FF;">=</span><span style="color: #000000;">y</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+                 <span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
+                 <span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">x</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #0000FF;">-(</span><span style="color: #000000;">y</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span> <span style="color: #000000;">directions</span><span style="color: #0000FF;">}</span>
+             <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
+         <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+     <span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
+     <span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Not found!"</span><span style="color: #0000FF;">}</span>
+ <span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
+ <span style="color: #008080;">constant</span> <span style="color: #000000;">example</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">},</span>
+                     <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">},</span>
+                     <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">},</span>
+                     <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">},</span>
+                     <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">},</span>
+                     <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">}}</span>
+ <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"X: %d, Y: %d, Path: %s\n"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">identifyPerimeter</span><span style="color: #0000FF;">(</span><span style="color: #000000;">example</span><span style="color: #0000FF;">))</span>
+<!--</lang>-->
+{{out}}
+<pre>
+X: 2, Y: -2, Path: SSESENNNWW
 </pre>