diff options
Diffstat (limited to 'drawinglayer/inc/drawinglayer/primitive2d/groupprimitive2d.hxx')
| -rw-r--r-- | drawinglayer/inc/drawinglayer/primitive2d/groupprimitive2d.hxx | 49 |
1 files changed, 40 insertions, 9 deletions
diff --git a/drawinglayer/inc/drawinglayer/primitive2d/groupprimitive2d.hxx b/drawinglayer/inc/drawinglayer/primitive2d/groupprimitive2d.hxx index 855e65ba98f8..89b49420a3e7 100644 --- a/drawinglayer/inc/drawinglayer/primitive2d/groupprimitive2d.hxx +++ b/drawinglayer/inc/drawinglayer/primitive2d/groupprimitive2d.hxx @@ -45,27 +45,58 @@ namespace drawinglayer { namespace primitive2d { + /** GroupPrimitive2D class + + Baseclass for all grouping 2D primitives + + The grouping primitive in it's basic form is capable of holding + a child primitive content and returns it on decomposition on default. + It is used for two main purposes, but more may apply: + + - to transport extended information, e.g. for text classification, + see e.g. TextHierarchy*Primitive2D implementations. Since they + decompose to their child content, renderers not aware/interested + in that extra information will just ignore these primitives + + - to encapsulate common geometry, e.g. the ShadowPrimitive2D implements + applying a generic shadow to a child sequence by adding the needed + offset and color stuff in the decomposition + + In most cases the decomposition is straightforward, so by default + this primitive will not buffer the result and is not derived from + BufferedDecompositionPrimitive2D, but from BasePrimitive2D. + + A renderer has to take GroupPrimitive2D derivations into account which + are used to hold a state. + + Current Basic 2D StatePrimitives are: + + - AlphaPrimitive2D (objects with freely defined transparence) + - InvertPrimitive2D (for XOR) + - MaskPrimitive2D (for masking) + - ModifiedColorPrimitive2D (for a stack of color modifications) + - TransformPrimitive2D (for a transformation stack) + */ class GroupPrimitive2D : public BasePrimitive2D { private: - // the children. Declared private since this shall never be changed at all after construction + /// the children. Declared private since this shall never be changed at all after construction Primitive2DSequence maChildren; - protected: - // local decomposition. Implementation will just return children - virtual Primitive2DSequence createLocalDecomposition(const geometry::ViewInformation2D& rViewInformation) const; - public: - // constructor + /// constructor GroupPrimitive2D(const Primitive2DSequence& rChildren); - // data access + /// data read access const Primitive2DSequence& getChildren() const { return maChildren; } - // compare operator + /// compare operator virtual bool operator==( const BasePrimitive2D& rPrimitive ) const; - // provide unique ID + /// local decomposition. Implementation will just return children + virtual Primitive2DSequence get2DDecomposition(const geometry::ViewInformation2D& rViewInformation) const; + + /// provide unique ID DeclPrimitrive2DIDBlock() }; } // end of namespace primitive2d |