PostScriptView(3U)

NAME
PostScriptView, PostScriptViews - base classes for external representation objects that generate PostScript code

SYNOPSIS
#include <Unidraw/Components/psview.h>

DESCRIPTION
PostScriptView is a PreorderView that serves as the abstract base class for external representation objects for emitting PostScript code. A PostScriptView's subject is normally a GraphicComp subclass. PostScriptViews is a subclass of PostScriptView for composite PostScript external views.

POSTSCRIPTVIEW PUBLIC OPERATIONS

virtual boolean Emit(ostream&)
    PostScriptView redefines Emit to generate header information. Thus you can call Emit on any PostScriptView subclass to generate encapsulated PostScript. Subclasses redefine Definition to generate the PostScript fragment that defines their basic attributes.

GraphicComp* GetGraphicComp()
    Return the subject.

POSTSCRIPTVIEW PROTECTED OPERATIONS

PostScriptView(GraphicComp* = nil)
    Initialize a PostScriptView, optionally of the given GraphicComp. The constructor is protected to disallow instantiation.

PostScriptView defines numerous protected helper functions to make it
easier for subclasses to generate the PostScript that describes their appearance. The output conforms to the original idraw PostScript format.

virtual void Comments(ostream&)

virtual void PSVersion(ostream&)

virtual void Creator(ostream&)

virtual void FontNames(ostream&)

virtual void Pages(ostream&)

virtual void BoundingBox(ostream&)
    The Comments operation generates a standard PostScript comments block. Comments calls the other operations to generate a complete set of comments.

virtual void Prologue(ostream&)

virtual void Version(ostream&)

virtual void GridSpacing(ostream&)

virtual void Trailer(ostream&)
    Operations that generate global data, procedures, and idraw-format-specific information.

virtual void MinGS(ostream&)

virtual void FullGS(ostream&)

virtual void TextGS(ostream&)

virtual void Brush(ostream&)

virtual void FgColor(ostream&)

virtual void BgColor(ostream&)

virtual void Font(ostream&)

virtual void Pattern(ostream&)

virtual void Transformation(ostream&)
    Operations that generate graphics state information. All output the graphics state attribute that their name suggests, with three exceptions: MinGS outputs a minimal set of graphics state defined by practical graphic objects, namely a brush, foreground and background colors, a pattern, and a transformation matrix. TextGS outputs the graphics state required by textual graphics, including a foreground color, a font, and a transformation matrix. FullGS generates a full set of graphics state.

virtual void SetPSFonts(UList*)

virtual UList* GetPSFonts()
    Get and set the list of all PostScript font names required by the PostScriptView. This set of names appears in a comment near the beginning of the generated output as required by standard PostScript conventions.

virtual void GetBox(Coord&, Coord&, Coord&, Coord&)
    Return the bounding box of the graphic for which PostScript is being generated. These values also appear in a standard PostScript comment.

virtual void GridSpacing(float&, float&)
    Return the grid spacing, if applicable. Idraw requires this information, and it is buried in a comment.

virtual void BeginProc(ostream&)

virtual void EndProc(ostream&)
    Begin and end a scope for defining a graphical object.

virtual void ConstProcs(ostream&)
    Generate PostScript procedures containing constant information, such as the character encoding dictionary, string length limit, etc.

virtual void SetGSProcs(ostream&)

virtual void SetBrushProc(ostream&)

virtual void SetFgColorProc(ostream&)

virtual void SetBgColorProc(ostream&)

virtual void SetFontProc(ostream&)

virtual void SetPatternProc(ostream&)
    Generate PostScript procedures for setting graphics state attributes.

virtual void ObjectProcs(ostream&)

virtual void BSplineProc(ostream&)

virtual void CircleProc(ostream&)

virtual void ClosedBSplineProc(ostream&)

virtual void EllipseProc(ostream&)

virtual void LineProc(ostream&)

virtual void MultiLineProc(ostream&)

virtual void PolygonProc(ostream&)

virtual void RectangleProc(ostream&)

virtual void TextProc(ostream&)
    Generate PostScript procedures for instantiating basic graphical objects.

virtual void MiscProcs(ostream&)

virtual void DefinitionProc(ostream&)

virtual void FillProc(ostream&)

virtual void StrokeProc(ostream&)

virtual void ShowProc(ostream&)

virtual void PatternProc(ostream&)

virtual void MinMaxProcs(ostream&)

virtual void MidpointProc(ostream&)

virtual void ThirdpointProc(ostream&)

virtual void SubsplineProc(ostream&)

virtual void StoreVerticesProc(ostream&)
    MiscProcs encapsulates calls to the subsequent PostScript procedure-generating operations shown above. DefinitionProc generates PostScript code that declares a procedure. FillProc and StrokeProc fill and stroke the path that a graphical object defines. ShowProc fine-tunes a text object's position. PatternProc creates a PostScript rendition of a pattern. MinMaxProcs define min and max functions. MidpointProc and ThirdpointProc calculate the point midway and one-third the way between two points, respectively. SubsplineProc breaks the vertices defining a spline into smaller pieces to allow approximating the spline with Bezier curves. Finally, StoreVerticesProc stores a set of vertices in arrays.

PSFont* GetFont(UList*)

PostScriptView* View(UList*)
    Convenience functions that return the PSFont and PostScriptView in UList elements, respectively.

PostScriptView* CreatePSView(GraphicComp*)
    Create the appropriate PostScriptView subclass for the given GraphicComp. The relationship between subjects, views, and view categories is encoded in their class identifiers. See classes(3U) for more information on class identifiers and view categories.

POSTSCRIPTVIEWS PUBLIC OPERATIONS

PostScriptViews(GraphicComps* = nil)~
    The constructor takes the subject as an optional argument.

virtual boolean Update()
    For simplicity, PostScriptViews reconciles its state with its subject's by destroying its children and reconstructing them from scratch.

POSTSCRIPTVIEWS PROTECTED OPERATIONS

UList* Elem(Iterator)
    A convenience function for extracting a UList from an iterator.

void DeleteView(Iterator&)

void DeleteViews()
    DeleteView removes a child and deletes it, while DeleteViews removes and deletes all children.

SEE ALSO
ExternView(3U), GraphicComp(3U), GraphicView(3U), UList(3U), classes(3U), idraw(1I), pspaint(3U)