====== The New Filter architecture ======

===== Implementing a New-Style Filter =====
=== Tips ===
  * If the filter has multiple instances (e.g. //Texture contrast I// and //II// on the //Lab Color/Contrast// tab) with different configurations (slider ranges, default values, …) see //ptFilter_LocalContrastStretch// and //ptFilter_TextureContrast// as examples for how to implement that.
  * If your filter arguments depend on the image’s scale factor see the same two classes as examples. Note that the current state of affairs is a kludge and not a proper solution. But it will last until the redesign of ptProcessor.

===== Porting Old-style Filters =====
  - Code the new filter as a class derived from //ptFilterBase//.
  - Create a new FUID entry in //ptFilterUids.h//. Order there is only for readability. Actually FUIDs for most of the filters are already there. In that case you only need to remove the “not yet ported” comment.
  - Add the new filter to //CreateAllFilters()// in ptMain starting around line 300. Order there is only for readability.
  - //ptSettings//
    * Remove old config lines from the lists in the constructor.
    * Remove the filter’s //if// branch(es) from //ToolInfo()//.
    * Check //ToolAlwaysVisible()// for the old name and remove.
  - //ptFilterDM:// Enter the new config item IDs to //FillNameMap()//. The old names are probably there already and are commented out.
  - //ptMain:// Remove old callbacks (//CB_old-config-name()// functions) and dispatcher macros in //CB_InputChanged()//.
  - //ptMainWindow:// If the old filter has buttons look for and remove //M_ConnectSomeButton// macros and associated callbacks. Also check for other non-standard widgets and their backend code.
  - //ptMainWindow.ui//
    * Find the old filter’s toolbox and delete all the widgets inside it (including the stretcher and top-level widget. Only the toolbox header must remain).
    * Change the toolbox caption (//currentItemText//) to the FUID and untick the //translatable// checkbox.
  - //ptProcessor::Run():// Change the call to the old filter to the new one, like this:<code cpp>
hFilter = GFilterDM->GetFilterFromName(Fuid::NEWFILTERNAME);
if (hFilter->isActive()) {
  m_ReportProgress(hFilter->caption());
  hFilter->runFilter(m_Image_AfterSOMETHING);
}</code>
    * Beware the //Camera// and //Output// tabs! Those are special cases.