I have been the Lead Developer of GeoGebra since 2007. I am responsible for the day-to-day coordination of programming, releases and keeping track of bugs.

Current Projects

• coordinating and programming GeoGebra 4.0

• coordinating GeoGebraMobile

• GeoPolyLine

• Hatching / filling

• Check these algorithms: ​http://local.wasp.uwa.edu.au/~pbourke/geometry/

Projects that could be delegated

• Axes options (allow to cross other than at the origin, display only certain portions)

• Memory management in applets

• Primary/Elementary Version

• eg JUnit testing

• Document code

• refector ExpressionNodeEvaluator (efficiency)

• rewrite getXML() to use Streams

• Tidy Script dialog

• live logging/tracing (web / bluetooth?)

• Webworks integration

• SCORM export / Moodle gradebook

​http://moodle.org/mod/forum/discuss.php?d=128908 ​http://moodle.org/mod/forum/discuss.php?d=88671 ​http://moodle.org/mod/forum/discuss.php?d=126716

• Dynamic Text Tool -> dialog to make Dynamic Texts

Either choose from a drop-down list of GeoElements, or type some free text with Add and Remove buttons

It will then create something like: a + "free text" + b +"" + c + "more free text"

Underneath there will then be a pane showing the objects (which can be dragged to change the order) eg a free text b c more free text

and a preview pane under that.

Look in the Textfield Tool for a similar dialog.

• a way to edit the objects whose visibility depends upon a checkbox

through a Tab in the Checkbox's properties (at the moment it's only possible through individual GeoElements in the Advanced -> Condition To Show Object Textfield)

• #54

Tickets

GeoGebra 4.0 milestone tickets:

#2

virtual keyboard doesn't work with rename dialog

#51

VirtualKeyboard: upper case Greek doesn't work in Word

#54

Optimise ExpressionNodeEvaluator

#55

add command SetLanguage["German"] or "de"

#57

javascript methods evalMaxima() and isMaximaAvailable(), setCAS()

#62

a = CopyFreeObject[a] + 1 makes 'a' a dependent object

#69

manage macros from xml

#127

accessibility commands/options to remove mouse dependency

#133

Point on object stays undefined

#142

drawing pad selection rectangle hangs

#154

add registerKeyboardListener, unregisterKeyboardListener

#181

Use the spreadsheet toolbar's color chooser in other places

#197

CopyGraphicsViewToClipboard[ ]

#205

text with dependent strings ("a" + a) can't be entetred into spreadsheet cells

#214

Context menus behave incorrectly under Snow Leopard

#222

different fill color and line color

#243

problem redefining point after undo

#245

add html export option to disable zoom

#277

Limit Limit[sin(x)/x,∞] is undefined

#301

Regular polygon -- segments not auxiliary before redefinition

#382

Whiteboard Perspective

#429

Unify display of line equations

#437

Double-height style bar for Younger Users (option)

#448

external defined slider velocity does change the definition of the slider when changed

#457

Start/Stop-button in text-preview

#483

f'(t) does not work at input-line

#485

add Point <-> List conversion

#488

style-bar of single-visible-view always visible

#510

filling wrong for large arcs

#512

FormulaText[a,false] gives number

#539

bug in Hull

#546

Pen Tool auxillary point and adjustment

#548

new points should have "standard" as style for the point-style

#569

Dragging point on Curve could be improved

#570

Improve display of integral when it goes a long way outside Graphics View

#677

problem if label has nested { { } } eg t_{y_{1_,}}

#699

Export of formulas

#721

Export of offline applets

#747

problem with Point[c] when c becomes undefined

#820

selected GeoButton bleeds color on a Mac

#830

A1=A1+1 -> 2 A1s in Algebra View

#831

Derivative[f(x+1)] calls the CAS multiple (100s) of times and fails

#861

Moving circle when single point

#876

Sort[] does not handle localized strings properly

#897

Name check is buggy in Object properties for variable names having subscripts

#904

Duplicate asymptotes to GeoFunction

#908

Graphcis View 2 keyboard shortcut problem

#910

opacity field in the advanced panel does not allow 1

#911

Default geo colors should match GeoGebraColor constants

#963

"Restore Default-Settings" not for axes-position and scaling?

#975

{{{1, 1}, {2, 1}}, {{1, 2}, {2, 2}}} displayed as flat list

#984

open stylebar when pen tool is selected

#985

eraser button in stylebar for pen tool

#1111

Asymptote[1/x] gives duplicate results

#1183

Open Webpage fails without message

#1194

Implement Intersect Parametric / Implicit curve when it can be solved by composite function

#1299

Use existing image for filling shape

#1318

"write tool" and "sketch tool"

#1328

integral throws exception when boolean evaluate is used

#1375

Bad interaction between Locus and EuclidianSettings

#1429

add prefsBase64 tag for applets

#1470

Support for pressure sensitive graphics tablets in the Pen Tool

#1487

too many decimals in slider dialog

#1519

Default labelling in Applets

#1525

Large distances between different font sizes

#1549

store undo point after zooming

#1609

x replaced with ggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarggbtmpvarx

#1729

Minimum spanning tree wrong for simple example

#1753

saving stylebar and titlebar settings to file xml

#1785

move N, integral unstable

#1792

angles of polygon faulty in ggbPrim

#1796

Add FitLineXY

#1855

set difference \ doesn't work with texts

#1920

problem with comma in label

#1923

circle fill shows chord line

#2097

problem saving/reloading file

#2102

labeling option and angles

#2176

Italics in LaTeX

GeoGebra 4.2 milestone tickets:

#293

segment styles

#1292

Hit Testing wrong for Segment[A,(inf,inf)]

#1300

Rotate[FormulaText[a],90°] -> null pointer

#1308

Integral[ℯ^(-x²), -1000, 0] gives 0

#1345

Attach / detach tool (use <alt>)

#1347

add ToUpperCase[] / ToLowerCase[]

#1349

allow LaTeX in buttons

#1361

Locus doesn't work with minimize

#1364

NIntegral[ ]

#1384

problem with ggbcasvarggbtmpvarrunicode95u2

#1395

new command RunScript[Object]

#1401

Attach/detatch tool: support points and images

#1410

replace commandtable with Enum & switch

#1411

Prevent kernel.statistics.AlgoXXX classes being loaded unnecessarily

#1422

new command: RandomPolynomial[ ]

#1438

Problems with redefining functions

#1467

new ggb command: Numeric

#1489

add forms ax+by+c=0 and ax^2 + bxy + cy^2 + dx + ey + f = 0

#1497

add ParametricDerivative[ curve ] command

#1503

copy and paste of GeoText creates duplicate geos

#1509

Application freezes when problems occur on loading JARs

#1536

cos²(1) not a free object

#1567

sort AV by construction order

#1601

{PolygonRegular[A,B,n]} when n changes

#1614

Algebra View first margin sometimes too big

#1631

NullPointerException at java.awt.Dimension

#1674

File properties

#1731

make dynamic text SpreadsheetTraceable

#1837

Keyboard shortcut for settings on Mac

#1878

Two issues with the Options Dialog

#1884

Reopen the same file doesn't work

#1958

export animated PDF

#1968

PenMode, endless loop

#1990

Construction Protocol could "skip" hidden objects

#1999

Better polygon algorithms (center of mass, intersections)

#2005

Put common.kernel.barycentric into a separate jar

#2024

Tools in the tools menu only do not work anymore

#2025

problem drawing inside polygon

#2039

Better font sizes

#2047

Pen Tool: click on an eg conic -> classcast

#2059

add Sum and Product commands to input bar

#2060

Attach doesn't work if construction order is not perserved

#2061

Improve GeoGebra 4.2 applet loading times

#2062

Geogebra colors problem with LaTeX-Export of GGB-Files

#2146

xAxis, yAxis, (zAxis) not translated when saving / loading scripts

#2181

Open Webpage doesn't work

GeoGebra 5.0 milestone tickets:

#68

display a number in % notation

#109

Shade tool

#148

Accessibility

#342

SD[list, list]

#428

commands for 3D vectors

#478

DynamicCoordinates for 3D points

#580

Templates for HTML export

#727

Construction::getGeoSetLabelOrder(GeoElement.GEO_CLASS_POINT) return also 3D points

#763

Add video playing

#774

extend round() command round(x,3)

#836

rename geo -> change references in scripts

#854

matrix * vector

#863

Camera tool ad/or smart selection rectangle

#868

Allow Curve[A+(r;θ_0+t),t,0,θ]

#877

FillShape and/or Merge

#892

Intersection problems in 2D/3D

#992

Microsoft Kinect

#1094

Allow (r; theta; phi) form for 3D points

#1115

syntax list1(1)

#1130

add FirstElement[] and LastElement[]

#1185

add Segment command

#1186

decorations for vectors

#1217

Introduce isVisible(int viewID) / setVisible(int viewID, boolean visible)

#1219

new script command Undo[n]

#1222

more display forms

#1230

add DecimalText[]

#1273

Update Apache Math to 3.0

#1296

support self-intersecting polygons properly

#1413

use "updateVisualStyle" for all views.

#1514

Drawables for polylines (2D/3D)

#1517

Drawables for list

#1654

Preferences too long

GeoGebraWebGui milestone tickets:

#1805

web: upload to GeoGebraTube

#1838

add support for ggb files (ChromeOS)

#1887

Issues with Relation (questions instead)

#1913

DrawEquationWeb.drawEquation doesn't work

#2027

web: checkbox shouldn't be draggable