Toggle for latex setting

LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/AppMenuBar.qml

@@ -22,6 +22,8 @@ import QtQuick.Dialogs 1.3
 import eu.ad5001.MixedMenu 1.1
 import "js/objects.js" as Objects
 import "js/historylib.js" as HistoryLib
+import "js/math/latex.js" as Latex
+
 
 /*!
     \qmltype AppMenuBar
@@ -139,6 +141,21 @@ MenuBar {
             onTriggered: Helper.setSettingBool("reset_redo_stack", checked)
             icon.name: 'timeline'
         }
+        
+        Action {
+            id: enableLatexSetting
+            text: qsTr("Enable LaTeX rendering")
+            checkable: true
+            checked: Helper.getSettingBool("enable_latex")
+            onTriggered: {
+                Helper.setSettingBool("enable_latex", checked)
+                Latex.enabled = checked
+                drawCanvas.requestPaint()
+            }
+            icon.name: 'Expression'
+            
+            Component.onCompleted: Latex.enabled = checked
+        }
     }
     
     Menu {

LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/LogGraphCanvas.qml

@@ -355,10 +355,11 @@ Canvas {
         Return format: dictionary {"width": width, "height": height}
     */
     function measureText(ctx, text) {
-        var theight = 0
+        let theight = 0
-        var twidth = 0
+        let twidth = 0
+        let defaultHeight = ctx.measureText("M").width // Approximate but good enough!
         text.split("\n").forEach(function(txt, i){
-            theight += canvas.textsize
+            theight += defaultHeight 
             if(ctx.measureText(txt).width > twidth) twidth = ctx.measureText(txt).width
         })
         return {'width': twidth, 'height': theight}

LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/Popup/GreetScreen.qml

@@ -18,6 +18,7 @@
 
 import QtQuick 2.12
 import QtQuick.Controls 2.12
+import "../js/math/latex.js" as Latex
 
 /*!
     \qmltype GreetScreen
@@ -101,7 +102,7 @@ Popup {
         text: qsTr('Check for updates on startup (requires online connectivity)')
         onClicked: {
             Helper.setSettingBool("check_for_updates", checked)
-            checkForUpdatesMenuSetting.checked = checked
+            //checkForUpdatesMenuSetting.checked = checked
         }
     }
     
@@ -113,7 +114,20 @@ Popup {
         text: qsTr('Reset redo stack when a new action is added to history')
         onClicked: {
             Helper.setSettingBool("reset_redo_stack", checked)
-            resetRedoStackMenuSetting.checked = checked
+            //resetRedoStackMenuSetting.checked = checked
+        }
+    }
+    
+    CheckBox {
+        id: enableLatexSetting
+        anchors.horizontalCenter: parent.horizontalCenter
+        anchors.top: resetRedoStackSetting.bottom
+        checked: Helper.getSettingBool("enable_latex")
+        text: qsTr('Enable LaTeX rendering')
+        onClicked: {
+            Helper.setSettingBool("enable_latex", checked)
+            Latex.enabled = checked
+            drawCanvas.requestPaint()
         }
     }
     

LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/js/math/latex.js

@@ -21,6 +21,11 @@
 .import "../expr-eval.js" as ExprEval
 
 
+/**
+ * true if latex has been enabled by the user, false otherwise.
+ */
+var enabled = false
+
 /**
  * Puts element within parenthesis.
  * 

LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/js/objs/common.js

@@ -279,7 +279,7 @@ class DrawableObject {
      * @param {function|null} getLatexFunction - Function (no argument) to get the latex markup to be displayed
      * @param {function|null} getTextFunction - Function (no argument) to get the text to be displayed
      * @param {function|null} drawFunctionLatex - Function (x,y,imageData) to display the latex image
-     * @param {function|null} drawFunctionText - Function (x,y,text) to display the text
+     * @param {function|null} drawFunctionText - Function (x,y,text,textSize) to display the text
      */
     drawLabel(canvas, ctx, labelPosition, posX, posY, forceText = false,
               getLatexFunction = null, getTextFunction = null, drawFunctionLatex = null, drawFunctionText = null) {
@@ -291,13 +291,13 @@ class DrawableObject {
         if(drawFunctionLatex == null)
             drawFunctionLatex = (x,y,ltxImg) => canvas.drawVisibleImage(ctx, ltxImg.source, x, y, ltxImg.width, ltxImg.height)
         if(drawFunctionText == null)
-            drawFunctionText = (x,y,text) => canvas.drawVisibleText(ctx, text, x, textSize.height+5)
+            drawFunctionText = (x,y,text,textSize) => canvas.drawVisibleText(ctx, text, x, y+textSize.height) // Positioned from left bottom
         // Drawing the label
         let offset
-        if(!forceText && true) { // TODO: Check for user setting with Latex.
+        if(!forceText && Latex.enabled) { // TODO: Check for user setting with Latex.
             // With latex
             let drawLblCb = function(canvas, ctx, ltxImg) {
-                this.drawPositionDivergence(labelPosition, 8, ltxImg, posX, posY, (x,y) => drawFunctionLatex(x,y,ltxImg))
+                this.drawPositionDivergence(labelPosition, 8+ctx.lineWidth/2, ltxImg, posX, posY, (x,y) => drawFunctionLatex(x,y,ltxImg))
             }
             let ltxLabel = getLatexFunction();
             if(ltxLabel != "")
@@ -306,7 +306,8 @@ class DrawableObject {
             // Without latex
             let text = getTextFunction()
             ctx.font = `${canvas.textsize}px sans-serif`
-            this.drawPositionDivergence(labelPosition, 4, canvas.measureText(ctx, text), posX, posY, (x,y) => drawFunctionText(x,y,text))
+            let textSize = canvas.measureText(ctx, text)
+            this.drawPositionDivergence(labelPosition, 8+ctx.lineWidth/2, textSize, posX, posY, (x,y) => drawFunctionText(x,y,text,textSize))
         }
     }
     

LogarithmPlotter/qml/eu/ad5001/LogarithmPlotter/js/objs/xcursor.js

@@ -168,7 +168,7 @@ class XCursor extends Common.DrawableObject {
         // Drawing label at the top of the canvas.
         this.drawLabel(canvas, ctx, this.labelPosition, xpos, 0, false, null, null,
                        (x,y,ltxImg) => canvas.drawVisibleImage(ctx, ltxImg.source, x, 5, ltxImg.width, ltxImg.height),
-                       (x,y,text) => canvas.drawVisibleText(ctx, text, x, textSize.height+5))
+                       (x,y,text,textSize) => canvas.drawVisibleText(ctx, text, x, textSize.height+5))
         
         // Drawing label at the position of the target element.
         if(this.targetValuePosition == 'Next to target' && this.targetElement != null) {
@@ -176,7 +176,7 @@ class XCursor extends Common.DrawableObject {
             this.drawLabel(canvas, ctx, this.labelPosition, xpos, ypos, false,
                            this.getTargetValueLatexLabel.bind(this), this.getTargetValueLabel.bind(this),
                            (x,y,ltxImg) => canvas.drawVisibleImage(ctx, ltxImg.source, x, y, ltxImg.width, ltxImg.height),
-                           (x,y,text) => canvas.drawVisibleText(ctx, text, x, y))
+                           (x,y,text,textSize) => canvas.drawVisibleText(ctx, text, x, y+textSize.height))
         }
     }
 }

LogarithmPlotter/util/config.py

@@ -26,6 +26,7 @@ DEFAULT_SETTINGS = {
     "check_for_updates": True,
     "reset_redo_stack": True,
     "last_install_greet": "0",
+    "enable_latex": True
 }
 
 # Create config directory