class TSVG: public TVirtualPS

 Default SVG constructor

 Initialize the SVG interface

  fname : SVG file name
  wtype : SVG workstation type. Not used in the SVG driver. But as TSVG
          inherits from TVirtualPS it should be kept. Anyway it is not
          necessary to specify this parameter at creation time because it
          has a default value (which is ignore in the SVG case).

 Open a SVG file

 Default SVG destructor

 Close a SVG file

 Activate an already open SVG file

 Deactivate an already open SVG file

 Draw a Box

 Draw a Frame around a box

 mode = -1  the box looks as it is behind the screen
 mode =  1  the box looks as it is in front of the screen
 border is the border size in already pre-computed SVG units dark is the
 color for the dark part of the frame light is the color for the light
 part of the frame

 Draw a PolyLine

  Draw a polyline through  the points  xy.
  If NN=1 moves only to point x,y.
  If NN=0 the x,y are  written  in the SVG        file
     according to the current transformation.
  If NN>0 the line is clipped as a line.
  If NN<0 the line is clipped as a fill area.

 Draw a PolyLine in NDC space

  Draw a polyline through  the points  xy.
  If NN=1 moves only to point x,y.
  If NN=0 the x,y are  written  in the SVG        file
     according to the current transformation.
  If NN>0 the line is clipped as a line.
  If NN<0 the line is clipped as a fill area.

 Paint PolyMarker

 Paint PolyMarker

 This function defines a path with xw and yw and draw it according the
 value of nn:

  If nn>0 a line is drawn.
  If nn<0 a closed polygon is drawn.

 Initialize the SVG file. The main task of the function is to ouput the
 SVG header file which consist in <title>, <desc> and <defs>. The
 HeaderPS provided by the user program is written in the <defs> part.

 Move to a new position (ix, iy). The move is done in relative coordinates
 which allows to have short numbers which decrease the size of the file.
 This function use the full power of the SVG's paths by using the
 horizontal and vertical move whenever it is possible.

 Start the SVG page. This function initialize the pad conversion
 coefficients and ouput the <svg> directive which is close later in the
 the function Close.

 Set the range for the paper in centimetres

 Set color index for fill areas

 Set color index for lines

 Change the line style

 linestyle = 2 dashed
           = 3 dotted
           = 4 dash-dotted
           = else solid (1 in is used most of the time)

 Set the lines width.

 Set color index for markers.

 Set color with its color index

 Set color with its R G B components

  r: % of red in [0,1]
  g: % of green in [0,1]
  b: % of blue in [0,1]

 Set color index for text

 Draw text

 xx: x position of the text
 yy: y position of the text
 chars: text to be drawn

 Write a string of characters in NDC

 Convert U from NDC coordinate to SVG

 Convert V from NDC coordinate to SVG

 Convert X from world coordinate to SVG

 Convert Y from world coordinate to SVG

 Begin the Cell Array painting

 Paint the Cell Array

 End the Cell Array painting

 Not needed in SVG case