added "center" to drop-down options of location blocks

(GO TO, POINT TOWARDS, DISTANCE TO and DIRECTION TO)

blocks.js

@@ -148,7 +148,7 @@ CustomCommandBlockMorph, SymbolMorph, ToggleButtonMorph, DialMorph*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.blocks = '2018-April-16';
+modules.blocks = '2018-May-02';
 
 var SyntaxElementMorph;
 var BlockMorph;
@@ -8421,6 +8421,7 @@ InputSlotMorph.prototype.distancesMenu = function () {
 	    dict['random position'] = ['random position'];
  	}
 	dict['mouse-pointer'] = ['mouse-pointer'];
+    dict['center'] = ['center'];
 
     stage.children.forEach(function (morph) {
         if (morph instanceof SpriteMorph && !morph.isTemporary) {

history.txt

@@ -4096,3 +4096,7 @@ in development:
 180427
 ------
 * GUI: when creating a new sprite only randomize color and direction when shift-clicking
+
+180502
+------
+* Blocks, Threads: added "center" to drop-down options of location blocks (GO TO, POINT TOWARDS, DISTANCE TO and DIRECTION TO)

threads.js

@@ -62,7 +62,7 @@ StageMorph, SpriteMorph, StagePrompterMorph, Note, modules, isString, copy,
 isNil, WatcherMorph, List, ListWatcherMorph, alert, console, TableMorph,
 TableFrameMorph, ColorSlotMorph, isSnapObject*/
 
-modules.threads = '2018-April-12';
+modules.threads = '2018-May-02';
 
 var ThreadManager;
 var Process;
@@ -2900,9 +2900,11 @@ Process.prototype.doFaceTowards = function (name) {
         thatObj;
 
     if (thisObj) {
-        if (this.inputOption(name) === 'mouse-pointer') {
+        if (this.inputOption(name) === 'center') {
+            thisObj.faceToXY(0, 0);
+        } else if (this.inputOption(name) === 'mouse-pointer') {
             thisObj.faceToXY(this.reportMouseX(), this.reportMouseY());
-        } if (this.inputOption(name) === 'random position') {
+        } else if (this.inputOption(name) === 'random position') {
         	thisObj.setHeading(this.reportRandom(1, 36000) / 100);
         } else {
             if (name instanceof List) {
@@ -2929,7 +2931,9 @@ Process.prototype.doGotoObject = function (name) {
         stage;
 
     if (thisObj) {
-        if (this.inputOption(name) === 'mouse-pointer') {
+        if (this.inputOption(name) === 'center') {
+            thisObj.gotoXY(0, 0);
+        } else if (this.inputOption(name) === 'mouse-pointer') {
             thisObj.gotoXY(this.reportMouseX(), this.reportMouseY());
         } else if (this.inputOption(name) === 'random position') {
 	        stage = thisObj.parentThatIsA(StageMorph);
@@ -3127,6 +3131,9 @@ Process.prototype.reportDistanceTo = function (name) {
         point = rc;
         if (this.inputOption(name) === 'mouse-pointer') {
             point = thisObj.world().hand.position();
+        } else if (this.inputOption(name) === 'center') {
+            return new Point(thisObj.xPosition(), thisObj.yPosition())
+                .distanceTo(new Point(0, 0));
         } else if (name instanceof List) {
             return new Point(thisObj.xPosition(), thisObj.yPosition())
                 .distanceTo(new Point(name.at(1), name.at(2)));
@@ -3149,6 +3156,9 @@ Process.prototype.reportDirectionTo = function (name) {
         if (this.inputOption(name) === 'mouse-pointer') {
             return thisObj.angleToXY(this.reportMouseX(), this.reportMouseY());
         }
+        if (this.inputOption(name) === 'center') {
+            return thisObj.angleToXY(0, 0);
+        }
         if (name instanceof List) {
             return thisObj.angleToXY(
                 name.at(1),