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Revision as of 08:36, 6 June 2010 by Ask (talk | contribs) (Add roadmap)

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TAChart is a charting LGPL component for Lazarus (TeeChart like). It contains the functions that Philippe Martinole developed for the TeleAuto project and lots of changes introduced by Luis Rodrigues while porting the Epanet application from Delphi to Lazarus. The code was then extensively rewritten, expanded and is now maintained by Alexander Klenin.

If you have questions, bug reports or feature requests, please post them to the Lazarus mailing list.


  • Pie Series
  • Bar Series
  • Area Series
  • Line Series (can work as Point Series)
  • Function Series with domain support
  • Unlimited number of series and points on graph
  • Flexible chart sources, including design-time editable, random, dynamic and db-aware sources.
  • Graph legend, title and footer
  • Axis labels and marks, manually set or auto-generated
  • Arbitrary number of axises per chart
  • Axis inversion, independent scale and offset, logarithmic scale
  • Interactive zoom
  • Reticule or vertical reticule with point measure
  • Auto or manual graph limits
  • Smart marks drawing
  • Vertical and horizontal lines
  • Easily extensible with new graph types


Here is an example of TAChart displaying a Line Series, Bar Series and Pie Series



Luís Rodrigues, Philippe Martinole, Alexander Klenin


The latest stable release can be found on the in the Lazarus SVN repository (The components are on the Chart Tab)

The old code developed by Philippe is Here: Lazarus CCR Files page.


See included examples in Lazarus source in (Lazarus Install Dir)/components/tachart/demo/


Below is a list of items that would be good to have in TAChart. Some of them are planned for implementation by the current maintainer, others will require patches from interested contributors.


  • TChartExtent editor
  • axis index editor
  • series index list editor
  • ListSource.DataPoints editor
  • marks.format / style editor
  • subcomponent editor
    • same ui as collection editor
    • convert to grid/checklist, show enabled/active checkboxes
    • child auto-renaming


  • finish multiaxis
    • auto-scaling to fixed/percent range
    • non-monotonic (?)
    • user-defined transform
    • partial-linear transform (?) partial zoom demo
    • inverted as transformation (?)
    • logBase 0 => e ?
  • finish TIntervalSource
  • various axis marks steps -- logarithmic etc.
  • "center" aligned axis
  • test/fix inverted axis


  • 3-d area series
  • 3-d pie series
  • rotated area series
  • custom "zero level" for area series
  • top-down and right-to-left series
  • Z axis
  • axis.Depth
  • FuncSeries.AxisIndexX
  • rotated func series
  • polar axis and series
  • LineStyle -> AxisIndex for TConstantLine (?)
  • moving series between charts
  • splines


  • fixed-point zooming
  • auto-panning (with timer)
  • animated zoom
  • userdefined tool
  • test/fix many charts per toolset
  • decouple reticule from TChart


  • caches
    • graphpoints
    • imagepoints
    • layers/barriers
  • use binsearch in more series


  • multi-source
    • stacked [full] bar series
    • stacked [full] area series
    • stacked/donut pie series (?)
    • range bar series
    • bubble series
  • TDateChartSource


  • complete rotated label support
  • auto-position labels


  • striped background => stripSeries
  • embellishments: gradient, shadow, glow(?)
  • transparency
  • Generic drawer: TCanvas/AggPas/OpenGL
  • panes


  • deprecate tbarchart
  • more documentation
  • oscilloscope demo
  • printing
  • better icons
  • lazreport integration
  • export to pdf/svg
  • tutorials
  • wizards


  • AddSubcomponent => SetParentComponent
  • extract TSubomponentClassRegistry