Chagall Reference   Fill                 12.5.93
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   Even such a common function like filling an area
   has special properties in Chagall, as may be 
   guessed from the corresponding dialog.

   To select the fill parameters you first need to
   select the fill colour. You can call up a colour
   selector by clicking on the coloured patch under
   'Fill-range'. A Colour selector..\TOOL\COLORBOX will appear in
   which you can either click on the desired shade 
   in the colour-square, drag the sliders, or click 
   on their arrows to make small adjustments (with a 
   digital read-out of the corresponding R, G and B or
   C, M, Y values); alternatively you can click on the
   number, clear the colour-value box that appears with 
   <Esc>, type in a new number and hit <Return>. The new 
   values are reflected immediately in the colour-square 
   and the adjacent sample patch. Return to the previous 
   dialog by clicking on 'OK' (or 'Abort' if you decide 
   you don't want to make a change) or by double-clicking 
   on the desired colour in the colour-square.

   You can speed up selection if you decide you don't 
   need the help of the colour square: Just click on
   the relevant R, G, B (or C, M, Y) numbers under 
   'Fill-range' and you can enter new values as 
   already described.

   You can also fill with a colour already present in
   the picture. For this click on 'Define' and then 
   click the open cross-hairs on the desired colour.

   Apart from the fill colour you can also specify
   in Chagall the tolerances that should be accepted 
   during filling. These are percentage values that
   determine by how much a colour present in the 
   picture may differ from the colour of the point 
   at which the fill-process started. 

   For filling you can also specify the 'Effective
   range' over which the process should be applied.
   When you select 'Activate' the mouse cursor turns
   into a funnel with which you can start the fill
   an area in the picture. The setting of the required 
   tolerances is sometimes rather complex and must be 
   established empirically in each case. Hence a short 
   example: If you want to equalise a given red tone 
   in the picture, then set the blue and green tolerance 
   to 100%, since these will not be included in the 
   consideration. You should increase the red tolerance, 
   starting from around 8%, until the colours you desire 
   to equalise are covered.

   If 'Magic wand' is not active, then after 'Execute'
   the whole of the picture (!) will be searched for
   colours within the tolerance of the colour defined 
   at the top of the box, and this will be replaced 
   by the chosen colour; otherwise the region around 
   the colour with its selected tolerances will be filled.
   
   The fill function respects the Mask..\MASK\MASK if the
   corresponding option is switched on, though only
   if this is a completely closed area.

   The fill region may be limited to a frame if desired
   by switching on the 'Frame only' option.


