etc/deps/geotypes/api.ts

@@ -101,7 +101,7 @@ export interface AppletObject {
   getXcoord(objName: string): number;
   getYcoord(objName: string): number;
   getZcoord(objName: string): number;
-  setCoords(objName: string, x: number, y: number, z: number): void;
+  setCoords(objName: string, x: number, y: number, z?: number): void;
   getValue(objName: string): number;
   getVersion(): string;
   getScreenshotBase64(callback: (data: string) => void, scale?: number): void;

src/adapptlet.civet

@@ -49,6 +49,28 @@ adapParams: AdapParams :=
       ? {loader: 'https://www.geogebra.org/apps/deployggb.js', joyceApplets: []}
       : JSON.parse(adapptScript.dataset.params ?? '') as AdapParams
 
+type ConstructionData
+  id: string
+  bg: RGB
+  is3d: boolean
+  width: number
+  height: number
+  elements: JoyceElements
+  pivot: string
+
+// Global data setup for pivoting (ugh, but necessary because the api
+// is not passed to the callback, so we have to look up the slider in
+// a global list):
+
+type PivotData
+  api: AppletObject
+  pivot: string
+  lastAngle: number
+  rotatable: string[]
+  fixed: Record<string, boolean>
+
+pivotData: Record<string, PivotData> := {}
+
 function postApplets(jApplets: AppletDescription[], codebase = '')
    for each jApp of jApplets
       params := {
@@ -58,10 +80,8 @@ function postApplets(jApplets: AppletDescription[], codebase = '')
          jApp.width,
          jApp.height,
          appletOnLoad: (api: AppletObject) =>
-            elements: JoyceElements := {}
+            is3d := contains3d jApp.params
-            backgroundRGB := [255, 255, 255] as RGB
+            if is3d
-            config3d := contains3d jApp.params
-            if config3d
                api.enable3D true
                api.setPerspective 'T'
                // Get rid of the xy-plane indicator
@@ -72,10 +92,24 @@ function postApplets(jApplets: AppletDescription[], codebase = '')
                api.setPerspective 'G'
             if adapParams.config?.algebra
                api.setPerspective '+A'
+            elements := {}
+            pivot .= ''
+            if 'pivot' in jApp.params
+               if is3d
+                  console.warn('Geometry Applet "pivot" only supported for '
+                     + '2D constrcutions. Ignoring.')
+               else
+                  pivot = geoname(jApp.id, elements, 'point') + 'Pivot'
+                  pivotData[pivot] = {
+                     api, jApp.params.pivot,
+                     lastAngle: 0, rotatable: [], fixed: {}}
+            cdata: ConstructionData := {
+               bg: ([255, 255, 255] as RGB),
+               is3d, jApp.id, jApp.width, jApp.height, elements, pivot}
             for name, value in jApp.params
                dispatchJcommand
-                  api, name, value, elements, backgroundRGB, config3d
+                  api, name, value, cdata
-            if config3d
+            if is3d
                depth .= jApp.width
                if jApp.height > depth then depth = jApp.height
                api.setCoordSystem
@@ -135,7 +169,7 @@ type ClassHandler = (
    method: string,
    args: JoyceArguments,
    index: number,
-   is3d: boolean) => Commander
+   cdata: ConstructionData) => Commander
 type RGB = [number, number, number]
 type XYZ = RGB
 
@@ -146,28 +180,26 @@ function dispatchJcommand(
       api: AppletObject,
       name: string,
       value: string,
-      elements: JoyceElements
+      cdata: ConstructionData): void
-      backgroundRGB: RGB,
-      is3d: boolean): void
    switch name
       'background'
-         newback := joyce2rgb value, backgroundRGB
+         cdata.bg = joyce2rgb value, cdata.bg
          if adapParams.config?.commands
             console.log 'Setting background to', value, 'interpreted as',
-               newback
+               cdata.bg
-         for i of [0..2]
+         api.setGraphicsOptions 1, bgColor: colorsea(cdata.bg).hex()
-            backgroundRGB[i] = newback[i]
-         api.setGraphicsOptions 1, bgColor: colorsea(backgroundRGB).hex()
       'title'
          if adapParams.config?.commands
             console.log 'Setting title to', value
-         corner := is3d ? 'Corner(-1,1)' : 'Corner(1,1)'
+         corner := cdata.is3d ? 'Corner(-1,1)' : 'Corner(1,1)'
          api.evalCommand `TitlePoint = ${corner}
             Text("${value}", TitlePoint + (2,5))`
+      'pivot'
+         return  // already handled in postApplets
       /e\[\d+\]/
          num := parseInt(name.slice(2))
          {commands, callbacks, parts} :=
-            jToG value, elements, num, backgroundRGB, is3d
+            jToG value, num, cdata
          if commands.length
             lastTried .= 0
             if commands.filter((&)).every (cmd) =>
@@ -180,16 +212,14 @@ function dispatchJcommand(
                 (part of translation of '${value}')
                 failed.`
          else console.warn `Could not parse command '${value}'`
-      else console.warn `Unkown param ${name} = ${value}`
+      else console.warn `Unknown param ${name} = ${value}`
 
 // Parses a Joyce element-creating command, extending the elements
 // by side effect:
 function jToG(
       jCom: string,
-      elements: JoyceElements,
       index: number,
-      backgroundRGB: RGB
+      cdata: ConstructionData): Commander
-      is3d: boolean): Commander
    [jname, klass, method, data, ...colors] := jCom.split ';'
    if adapParams.config?.commands
       console.log 'Defining', jname, 'as a', klass, 'constructed by',
@@ -199,7 +229,9 @@ function jToG(
       console.warn `Unknown entity class ${klass}`
       return cmdr
    assertJoyceClass klass  // shouldn't need to do that :-/
-   name := if /^\p{L}\w*$/u.test jname then jname else geoname jname, elements
+   isPivot := !!cdata.pivot and jname is pivotData[cdata.pivot].pivot
+   name := geoname jname, cdata.elements, klass
+   if isPivot then pivotData[cdata.pivot].pivot = name
    args: JoyceArguments := {}
    usesCaptions := []
    for each jdep of data.split ','
@@ -207,17 +239,17 @@ function jToG(
       if scalar is scalar // not NaN
          (args.scalar ?= []).push scalar
          continue
-      unless jdep in elements
+      unless jdep in cdata.elements
          console.warn `Reference to unknown geometric entity ${jdep} in $jCom}`
          return cmdr
       usesCaptions.push jdep
-      {klass: depKlass, otherName: depGeo, ends} := elements[jdep]
+      {klass: depKlass, otherName: depGeo, ends} := cdata.elements[jdep]
       (args[depKlass] ?= []).push depGeo
       if depKlass is 'point'
          (args.subpoints ?= []).push depGeo
       else if depKlass is 'line'
          (args.subpoints ?= []).push ...ends ?? []
-   cmdr = classHandler[klass] name, method, args, index, is3d
+   cmdr = classHandler[klass] name, method, args, index, cdata
    unless name is jname then cmdr.callbacks.push (api: AppletObject) =>
       api.setCaption name, jname
       api.setLabelStyle name, 3  // style CAPTION = 3
@@ -226,6 +258,25 @@ function jToG(
          for each aux of cmdr.auxiliaries
             api.setAuxiliary aux, true
             api.setVisible aux,false
+
+   // set up the pivot if there is one
+   if isPivot
+      unless klass is 'point'
+         console.warn(`Can only pivot around a point, not the ${klass}`
+            + `named ${jname}. Ignoring.`)
+         cdata.pivot = ''
+      cmdr.commands.push(`${cdata.pivot} = `
+         + `Slider(0°,360°,1°,1,${cdata.width/3},true,true,false,false)`)
+      cmdr.callbacks.push (api: AppletObject) =>
+         api.setCaption cdata.pivot, 'Rotate Display'
+         api.setLabelStyle cdata.pivot, 3
+         api.setCoords(cdata.pivot, 2*cdata.width/3, cdata.height-10)
+         // Not sure how to let TypeScript deal with putting a new function
+         // on the global window object, so punting at least for now:
+         // @ts-ignore
+         window.pivotListener = pivotListener
+         api.registerObjectUpdateListener(cdata.pivot, 'pivotListener')
+
    // Create callback to assign colors
    if colors.length is 4 and colors.every (color) => invisible color
       cmdr.callbacks.push (api: AppletObject) => api.setVisible name, false
@@ -243,11 +294,11 @@ function jToG(
                    console.log 'Fading out interior of', face if trace
                    // hide the interior by making it transparent
                    api.setFilling face, 0
-                else if face not in elements
+                else if face not in cdata.elements
                    console.log 'Hiding face', face if trace
                    api.setVisible face, false
          else
-            faceRGB := joyce2rgb(colors[3] or 'brighter', backgroundRGB)
+            faceRGB := joyce2rgb(colors[3] or 'brighter', cdata.bg)
             deep := ['circle', 'polygon', 'sector']
             filling := deep.includes(klass) ? 0.7 : 0.2
             for each face of parts[2]
@@ -259,28 +310,30 @@ function jToG(
          // Lines default to black:
          if invisible colors[2]
             for each line of parts[1]
-                if line is name or line not in elements
+                if line is name or line not in cdata.elements
                    console.log 'Hiding line', line if trace
                    api.setVisible line, false
          else
-            lineRGB := joyce2rgb(colors[2] or 'black', backgroundRGB)
+            lineRGB := joyce2rgb(colors[2] or 'black', cdata.bg)
             for each line of parts[1]
                console.log 'Coloring line', line, 'to', colors[2] if trace
                api.setVisible line, true
                api.setColor line, ...lineRGB
 
          // Now color the points:
-         console.log 'Considering point colors for', name if trace
+         if trace
+            console.log
+               'Considering point colors for', name, 'of dimension', dimension
          if invisible colors[1]
             // Hide all the dim-0 elements that are not distinct independent
             // items:
             for each point of parts[0]
-               if point is name or point not in elements
+               if point is name or point not in cdata.elements
                   console.log 'Hiding point', point if trace
                   api.setVisible point, false
          else if dimension is 0 or colors[1] // Need to color the points
-            ptRGB := colors[1] ? joyce2rgb colors[1], backgroundRGB
+            ptRGB := colors[1] ? joyce2rgb colors[1], cdata.bg
-               : pointDefaultRGB name, method
+               : pointDefaultRGB name, method, isPivot
             for each point of parts[0]
                console.log 'Coloring point', point, 'to', colors[1] if trace
                api.setVisible point, true
@@ -290,12 +343,12 @@ function jToG(
          if invisible colors[0]
             console.log 'Hiding label', name if trace
             api.setLabelVisible name, false
-         else if colors[dimension] and colors[dimension] is not colors[0]
+         else if colors[dimension+1] and colors[dimension+1] is not colors[0]
             // Have to make a text to provide the caption, since GeoGebra
             // doesn't allow caption different color from entity.
             textName := 'GeoText' + index
             locationExpr := switch klass
-               when 'point' then `1.02${name})`
+               when 'point' then `1.02${name}`
                when 'line'
                   (`Midpoint(${name}) + `
                   + `Rotate(Direction(${name})*Length(${name})*0.02, pi/2)`)
@@ -315,8 +368,12 @@ function jToG(
                   unless parts[0].includes ex1 then ex1 = `Centroid(${ex1})`
                   unless parts[0].includes ex2 then ex2 = `Centroid(${ex2})`
                   `(4*${ex1}+${ex2})/5`
-            api.evalCommand `${textName} = Text("${jname}", ${locationExpr})`
+            textCmd := `${textName} = Text("${jname}", ${locationExpr})`
-            api.setColor textName, ...joyce2rgb colors[0], backgroundRGB
+            textCol := joyce2rgb colors[0], cdata.bg
+            if trace
+               console.log `Making text '${textCmd}' colored`, textCol
+            api.evalCommand textCmd
+            api.setColor textName, ...textCol
             // and hide the underlying GeoGebra label
             api.setLabelVisible name, false
          else if colors[0]
@@ -331,19 +388,35 @@ function jToG(
             console.log 'Setting label vis of', name, 'to', show if trace
             api.setLabelVisible name, show
 
-//         window[hideListener] = (arg) =>
+   cdata.elements[jname] = {otherName: name, usesCaptions, klass, cmdr.ends}
-//            api.setVisible name, false
+   cdata.elements[name] = {otherName: jname, usesCaptions, klass, cmdr.ends}
-//         api.registerObjectUpdateListener name, hideListener
-   if cmdr.ends // line or sector
-      elements[jname] =
-         {otherName: name, usesCaptions, klass, cmdr.ends}
-      elements[name] =
-         {otherName: jname, usesCaptions, klass, cmdr.ends}
-   else // any other geometry
-      elements[jname] = {otherName: name, usesCaptions, klass}
-      elements[name] = {otherName: jname, usesCaptions, klass}
    cmdr
 
+function pivotListener(slider: string)
+   pd := pivotData[slider]
+   newval := pd.api.getValue slider
+   if newval is pd.lastAngle then return
+   rotation := newval - pd.lastAngle
+   pd.lastAngle = newval
+   pX := pd.api.getXcoord pd.pivot
+   pY := pd.api.getYcoord pd.pivot
+   relX: Record<string, number> := {}
+   relY: Record<string, number> := {}
+   for each anchor of pd.rotatable
+      relX[anchor] = pd.api.getXcoord(anchor) - pX
+      relY[anchor] = pd.api.getYcoord(anchor) - pY
+      console.log 'Unfixing', anchor, relX[anchor], relY[anchor]
+      pd.api.setFixed anchor, false
+   ct := Math.cos rotation
+   st := Math.sin rotation
+   for each anchor of pd.rotatable
+      rX := relX[anchor]*ct - relY[anchor]*st
+      rY := relY[anchor]*ct + relX[anchor]*st
+      pd.api.setCoords(anchor, rX + pX, rY + pY)
+      if pd.fixed[anchor]
+         console.log 'Re-fixing', anchor, rX, rY
+         pd.api.setFixed anchor, true
+
 function invisible(cname: string): boolean
    if adapParams.config?.showall then return false
    cname is '0' or cname is 'none'
@@ -397,8 +470,8 @@ function joyce2rgb(cname: string, backgroundRGB?: RGB): RGB
          console.warn 'Could not parse color:', cname
          [128, 128, 128]
 
-function pointDefaultRGB(name: string, method: string): RGB
+function pointDefaultRGB(name: string, method: string, isPivot: boolean): RGB
-   // Need to short-circuit with green for pivot point, once that is implemented
+   if isPivot then return joyce2rgb 'green'
    switch method
       'free'
          joyce2rgb 'red'
@@ -406,7 +479,14 @@ function pointDefaultRGB(name: string, method: string): RGB
          joyce2rgb 'orange'
       else joyce2rgb 'black'
 
-function geoname(jname: JoyceName, elements: JoyceElements): GeoName
+function geoname(
+      jname: JoyceName, elements: JoyceElements, klass: JoyceClass): GeoName
+   unless jname.substring(0,3) is 'Geo' // those might clash
+      // Names with word characters starting with a capital are always good:
+      if /^[A-Z]['\w]*$/.test jname then return jname
+      // If it's not a point, can start with any letter:
+      if klass !== 'point' and /^\p{L}['\w]*$/u.test jname then return jname
+   // GeoGebra won't deal with this name, so hash it:
    numCode .= 0n
    numCode = numCode*128n + BigInt ch.codePointAt(0) ?? 1 for each ch of jname
    return .= 'Geo' + numCode.toString(36);
@@ -426,11 +506,12 @@ function cutoffExtend(
 // All of the detailed semantics of each available command lies in this
 // function.
 classHandler: Record<JoyceClass, ClassHandler> :=
-   point: (name, method, args, index, is3d): Commander =>
+   point: (name, method, args, index, cdata): Commander =>
       return := freshCommander()
       {commands, callbacks, parts, auxiliaries} := return.value
-      zeroVector := is3d ? 'Vector((0,0,0))' : 'Vector((0,0))'
+      zeroVector := cdata.is3d ? 'Vector((0,0,0))' : 'Vector((0,0))'
       aux := name + 'aUx'
+      pivotable := cdata.pivot and name !== pivotData[cdata.pivot].pivot
       parts[0].push name
       switch method
          /angle(?:Bisector|Divider)/
@@ -445,7 +526,7 @@ classHandler: Record<JoyceClass, ClassHandler> :=
                commands.push `${destination} = Segment(${start}, ${end})`
             else destination = args.line[0]
             n := method is 'angleBisector' ? 2 : args.scalar?[0]
-            inPlane := is3d ? `, Plane(${start}, ${center}, ${end})` : ''
+            inPlane := cdata.is3d ? `, Plane(${start}, ${center}, ${end})` : ''
             commands.push
                `${aux}2 = Angle(${start}, ${center}, ${end}${inPlane})`
                `${aux}3 = If(${aux}2 > pi, ${aux}2 - 2*pi, ${aux}2)`
@@ -454,7 +535,12 @@ classHandler: Record<JoyceClass, ClassHandler> :=
             auxiliaries.push ...[2..4].map (i) => `${aux}${i}`
          'circleSlider'
             unless args.circle then return
-            commands.push `${name} = Point(${args.circle[0]})`
+            circ := args.circle[0]
+            commands.push `${name} = Point(${circ})`
+            if (pivotable
+                  and cdata.elements[circ].ends?[0] // center
+                      is pivotData[cdata.pivot].pivot)
+               pivotData[cdata.pivot].rotatable.push name
             if args.scalar and args.scalar.length
                callbacks.push (api: AppletObject) =>
                   api.setCoords name, ...args.scalar as XYZ
@@ -466,12 +552,15 @@ classHandler: Record<JoyceClass, ClassHandler> :=
             commands.push `${name} = Translate(${source}, ${displacement})`
          'first'
             unless args.subpoints then return
-            commands.push `${name} = Point(${args.subpoints[0]},${zeroVector})`
+            commands.push `${name} = ${args.subpoints[0]}`
          /fixed|free/
             coords := args.scalar
             unless coords then return
-            commands.push `${name} = Point({${coords.join ','}})`
+            scoord := coords.join ','
+            if pivotable then pivotData[cdata.pivot].rotatable.push name
+            commands.push `${name} = (${scoord})`
             if method is 'fixed'
+               if pivotable then pivotData[cdata.pivot].fixed[name] = true
                callbacks.push (api: AppletObject) => api.setFixed name, true
          'foot'
             pt := args.subpoints
@@ -492,7 +581,7 @@ classHandler: Record<JoyceClass, ClassHandler> :=
          'last'
             unless args.subpoints then return
             commands.push
-               `${name} = Point(${args.subpoints.at(-1)}, ${zeroVector})`
+               `${name} = ${args.subpoints.at(-1)}`
          'lineSegmentSlider'
             segment .= args.line?[0]
             unless segment
@@ -524,7 +613,7 @@ classHandler: Record<JoyceClass, ClassHandler> :=
                unless pt.length is 5 then return
                sourcePlane .= ''
                destPlane .= ''
-               if is3d
+               if cdata.is3d
                   unless args.plane then return
                   destPlane = `, ${args.plane[0]}`
                   if args.plane.length > 1
@@ -544,7 +633,7 @@ classHandler: Record<JoyceClass, ClassHandler> :=
             commands.push
                `${name} = Vertex(${args.polygon?[0]},${args.scalar?[0]})`
 
-   line: (name, method, args, index, is3d) =>
+   line: (name, method, args, index, cdata) =>
       return := freshCommander()
       return.value.ends = ['', '']
       {commands, callbacks, parts, auxiliaries, ends} := return.value
@@ -561,7 +650,7 @@ classHandler: Record<JoyceClass, ClassHandler> :=
             unless cr return
             commands.push ...[1..2].map (n) =>
               `${aux}${n} = Intersect(${cr[0]}, ${cr[1]}, ${n})`
-            inPlane := is3d ? `Plane(${cr[0]})` : ''
+            inPlane := cdata.is3d ? `Plane(${cr[0]})` : ''
             ctr := cr.map (c) => `Center(${c})`
             condition := (`Angle(${aux}1,${ctr[0]},${ctr[1]}${inPlane})`
                + `< Angle(${aux}2,${ctr[0]},${ctr[1]}${inPlane})`)
@@ -630,7 +719,8 @@ classHandler: Record<JoyceClass, ClassHandler> :=
 
    circle: (name, method, args) =>
       return := freshCommander()
-      {commands, callbacks, parts, auxiliaries} := return.value
+      return.value.ends = ['', '']
+      {commands, callbacks, parts, auxiliaries, ends} := return.value
       parts[2].push name
       parts[1].push name
       switch method
@@ -641,10 +731,12 @@ classHandler: Record<JoyceClass, ClassHandler> :=
             switch pt.length
                when 2
                   [center, point] := pt
+                  ends[0] = center
                   commands.push
                      `${name} = Circle(${center}, ${point}${inPlane})`
                when 3
                   center := pt[0]
+                  ends[0] = center
                   radius := `Distance(${pt[1]}, ${pt[2]})`
                   commands.push
                      `${name} = Circle(${center}, ${radius}${inPlane})`