cppcanvas/source/inc/action.hxx

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  19
  20 #ifndef _CPPCANVAS_ACTION_HXX
  21 #define _CPPCANVAS_ACTION_HXX
  22
  23 #include <sal/types.h>
  24
  25 #include <boost/shared_ptr.hpp>
  26
  27 namespace basegfx
  28 {
  29     class B2DHomMatrix;
  30     class B2DRange;
  31 }
  32
  33
  34 /* Definition of Action interface */
  35
  36 namespace cppcanvas
  37 {
  38     namespace internal
  39     {
  40         /** Interface for internal render actions
  41
  42             This interface is implemented by all objects generated
  43             from the metafile renderer, and corresponds roughly to the
  44             VCL meta action.
  45          */
  46         class Action
  47         {
  48         public:
  49             /** Used for rendering action subsets
  50
  51                 There are several cases where an Action might have
  52                 subsettable content, e.g. text, or referenced
  53                 metafiles, like the transparent action.
  54
  55                 Generally, at the metafile renderer, all actions are
  56                 'flattened' out, i.e. a meta action rendering the
  57                 string "Hello" counts five indices, and a transparent
  58                 action containing a metafile with 100 actions counts
  59                 at least 100 indices (contained transparency or text
  60                 actions recursively add to this value). From the
  61                 outside, the subset to render is referenced via this
  62                 flat index range
  63              */
  64             struct Subset
  65             {
  66                 /** Denotes start of the subset.
  67
  68                     The index given here specifies the first subaction
  69                     to render.
  70                  */
  71                 sal_Int32   mnSubsetBegin;
  72
  73                 /** Denotes end of the subset
  74
  75                     The index given here specifies the first subaction
  76                     <em>not<em> to render, i.e. one action behind the
  77                     subset to be rendered
  78                  */
  79                 sal_Int32   mnSubsetEnd;
  80             };
  81
  82             virtual ~Action() {}
  83
  84             /** Render this action to the associated canvas
  85
  86                 @param rTransformation
  87                 Transformation matrix to apply before rendering
  88
  89                 @return true, if rendering was successful. If
  90                 rendering failed, false is returned.
  91              */
  92             virtual bool render( const ::basegfx::B2DHomMatrix& rTransformation ) const = 0;
  93
  94             /** Render the given part of the action to the associated
  95                 canvas.
  96
  97                 @param rTransformation
  98                 Transformation matrix to apply before rendering
  99
 100                 @param rSubset
 101                 Subset of the action to render. See Subset description
 102                 for index semantics.
 103
 104                 @return true, if rendering was successful. If the
 105                 specified subset is invalid for this action, or if
 106                 rendering failed for other reasons, false is returned.
 107              */
 108             virtual bool renderSubset( const ::basegfx::B2DHomMatrix& rTransformation,
 109                                        const Subset&                  rSubset ) const = 0;
 110
 111             /** Query bounds of this action on the associated canvas
 112
 113                 @param rTransformation
 114                 Transformation matrix to apply
 115
 116                 @return the bounds for this action in device
 117                 coordinate space.
 118              */
 119             virtual ::basegfx::B2DRange getBounds( const ::basegfx::B2DHomMatrix& rTransformation ) const = 0;
 120
 121             /** Query bounds for the given part of the action on the
 122                 associated canvas.
 123
 124                 @param rTransformation
 125                 Transformation matrix to apply.
 126
 127                 @param rSubset
 128                 Subset of the action to query. See Subset description
 129                 for index semantics.
 130
 131                 @return the bounds for the given subset in device
 132                 coordinate space.
 133              */
 134             virtual ::basegfx::B2DRange getBounds( const ::basegfx::B2DHomMatrix&   rTransformation,
 135                                                    const Subset&                    rSubset ) const = 0;
 136
 137             /** Query action count.
 138
 139                 This method returns the number of subset actions
 140                 contained in this action. The render( Subset ) method
 141                 must accept subset ranges up to the value returned
 142                 here.
 143
 144                 @return the number of subset actions
 145              */
 146             virtual sal_Int32 getActionCount() const = 0;
 147         };
 148
 149         typedef ::boost::shared_ptr< Action > ActionSharedPtr;
 150
 151     }
 152 }
 153
 154 #endif /* _CPPCANVAS_ACTION_HXX */
 155
 156 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */