Differences

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--- dev:program_ulam [2015/06/01 18:07] – [Capitalization Matters] xychen
+++ dev:program_ulam [2016/01/14 07:13] (current) – ackley
@@ Line 21: / Line 21: @@
 ==== EventWindow Indices ====
-Left picture is an indices map within an EventWindow. The sites are labeled from 1 to 40. Right is a colored map. We use different names to distinct different 'tens'. For 1 to 10 we use W1,..,W0. For 11 to 20 we use E1,...,E0. For 21 to 30 we use F1,...,F0. And from 31 to 40 we use G1,...,G0.
+{{ :dev:event-window-10.png?300|}} The image at right (click to enlarge) shows the indexing scheme used for sites within an ''EventWindow''.  Both 2D 'coord' numbering and a 1D 'site number' approach are offered.
-{{:dev:ew_index.png?220 |}}{{:dev:mfms_ew_index.png?260 |}}
+The ''getCoord(siteNum)'' function converts an 1D index (which is an ''Unsigned(6)'' ) to a 2D coordinate (which is a quark ''C2D''). The ''getSiteNumber(coord)'' convert ''C2D'' back to 1-d ''Unsigned(6)''.  The quark ''C2D'' has ''getX()'' and ''getY()'' methods to access the //x// and //y// coordinate values individually.
+In general, when code is referring to individual fixed sites within the event window, the 1D coordinate system is used (see the 'First' element below for an example).  Two-dimensional C2D indexing is more commonly used when there is some flexibility depending on geometry or relative positions.
 ===== The 'First' Element =====
@@ Line 32: / Line 36: @@
   EventWindow ew;
   Void behave(){
-    ew[1]=ew[0];
+    ew[1]=ew[0]; // Copy self one site west
   }
 }
@@ Line 318: / Line 322: @@
 }
 </code>
+===== Node Elements =====
+We have some cool features in the new MFM simulator. One of them is that an Atom can change its color dynamically. We made this little ''Node'' element to simulate a neuron node. When a ''Node'' is triggered by its //left neighbors// within its ''EventWindow'', it fires. We let a ''Node'' to display various colors as long as it is trigger. If it doesn't fire, it remains dark.
+{{:dev:node_init.png?250|}}
+<code - Node.ulam>
+/**
+  Node is a demo element.
+  \color #986
+  \symbol Nd
+  \symmetries normal
+*/
+element Node{
+  typedef Unsigned(6) SiteNum;
+  typedef Int(16) Coord;
+  typedef Unary(1) FireFlag;
+  typedef Int(4) Weight;
+  typedef Unsigned(8) ARGB[4];
+  typedef Unsigned(8) ColorValue;
+  DebugUtils du;
+  EventWindow ew;
+  Once oc;
+  AtomUtils au;
+  Weight wa;
+  Weight wm;
+  Weight wb;
+  FireFlag fire;
+  Weight thresh;
+  ColorValue red;
+  ColorValue grn;
+  ColorValue blu;
+  Int getSum(){
+    Int sum;
+    C2D mcd;
+    WindowServices ws;
+    ws.reset(1,4);
+    for(Int slot=ws.next();slot>=0;slot=ws.next()){
+      if(ew[slot] is Node){
+	Atom a=ew[slot];
+	Node you=(Node) a;
+	mcd=ew.getCoord((SiteNum)slot);
+	Coord mx=mcd.getX();
+	Coord my=mcd.getY();
+	if(mx<0){
+	  if(my<0){
+	    sum=sum+wa*you.fire;
+	  }else if(my==0){
+	    sum=sum+wm*you.fire;
+	  }else if(my>0){
+	    sum=sum+wb*you.fire;
+	  }
+	}
+      }
+    }
+    return sum;
+  }
+  FireFlag getFire(Int s){
+    if(s>=thresh){
+      return 1;
+    }
+    return 0;
+  }
+  Void initSelf(){
+    Random rd;
+    Weight w;
+    wa=(Weight)rd.between((Int)w.minof,(Int)w.maxof);
+    wm=(Weight)rd.between((Int)w.minof,(Int)w.maxof);
+    wb=(Weight)rd.between((Int)w.minof,(Int)w.maxof);
+    thresh=(Weight)rd.between((Int)w.minof,(Int)w.maxof);
+  }
+  Void changeColor(){
+    Random rd;
+    red=rd.between(0,3)*80+rd.between(0,16);
+    grn=rd.between(0,3)*80+rd.between(0,16);
+    blu=rd.between(0,3)*80+rd.between(0,16);
+  }
+  ARGB getColor(Unsigned selector){
+    ColorUtils cu;
+    ARGB ret=cu.color(0xff00ff00u);
+    if(fire==1){
+      ret[1]=red;
+      ret[2]=grn;
+      ret[3]=blu;
+    }else{
+      ret=cu.color(0xff090806u);
+    }
+    return ret;
+  }
+  Void behave(){
+    Int msum;
+    if(oc.new()){
+      initSelf();
+      du.printContext();
+    }
+    msum=getSum();
+    fire=getFire(msum);
+    changeColor();
+  }
+}
+</code>
+We use a ''Once'' quark to call the ''initSelf()'' //once//. We have used a lot of quarks before without realizing that. The ''EventWindow'', ''DebugUtils'', ''Random'', ''AtomUtils'' are all quarks. It's the same thing here to use a ''Once'': instantiate ''Once oc'', then use ''oc.new()'' to decide if this is the first time of a call.
+In the ''changeColor()'' of this ''Node'' element, we use ''ARGB getColor()'' to give new color values. This ''getColor()'' returns a array with Four values: //Opacity//, //Red//, //Green// and //Blue//.
+Like other Neurons, our ''Node'' will be fired by neighbors. In this simplified case, only the //left neighbors// can trigger our ''Nodes''. This time we need to scan the whole ''EventWindow''. To decide which neighbors are located to the left we use C2D coordinate. Those Atoms with negative x coordinate are to the left of our ''Node''.