snap.h

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// $Id: snap.h 1718 2006-08-25 11:06:06Z martin $
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 */
// The Snap class - used to do all types of snapping in Camelot

#ifndef INC_SNAP
#define INC_SNAP

class Spread;
class DocView;
class DocCoord;
class DocRect;
class Node;
class Layer;
class Path;

enum GuidelineType  { GUIDELINE_NOTYPE, GUIDELINE_HORZ, GUIDELINE_VERT };

/********************************************************************************************

>   class CSnap : public CC_CLASS_MEMDUMP

    Author:     Mark_Neves (Xara Group Ltd) <camelotdev@xara.com>
    Created:    20/9/94
    Purpose:    Performs the snapping required by Camelot

********************************************************************************************/

class CSnap : public CC_CLASS_MEMDUMP
{
CC_DECLARE_MEMDUMP(CSnap);

public:
    CSnap(DocView* pThisDocView,Spread* pThisSpread);

    // General snap functions of DocView.
    BOOL Snap(DocCoord* pDocCoord, BOOL TryMagSnap = TRUE,
                                   BOOL TryGridSnap = TRUE);
    BOOL Snap(DocRect* pDocRect, const DocCoord& PrevCoord, const DocCoord& CurCoord);

    BOOL TryToSnapToObject(Node* pNode, DocCoord* pDocCoord);

    BOOL SnapToGrids(DocCoord* pDocCoord);
    BOOL SnapToGuidelines(DocCoord* pDocCoord,GuidelineType Type = GUIDELINE_NOTYPE);

    void SetSpread(Spread* pThisSpread) { pSpread = pThisSpread; }

    static MILLIPOINT GetSnapDist() { return SnapDist; }
    static MILLIPOINT GetSnapToCoordDist() { return SnapToCoordDist; }

    static BOOL SnapCoordToPath(DocCoord* pDocCoord, Path* pPath);

    static BOOL SnapRectToRect(DocRect* pSnappedRect, const DocRect& RefRect);

private:
    // Internal snap-to-grid funcs
    BOOL SnapToGrids(DocRect* pDocRect, const DocCoord& PrevCoord, const DocCoord& CurCoord);

    // Internal snap-to-objects funcs
    // if Magnetic is TRUE, only magnetic objects are snapped to, otherwise all objects are snapped to.
    BOOL SnapToObjects(Node* pRootNode,DocCoord* pDocCoord,BOOL Magnetic,BOOL GuideLayersOnly);
    BOOL SnapToObjects(DocRect* pDocRect, const DocCoord& PrevCoord, const DocCoord& CurCoord, BOOL Magnetic,BOOL GuideLayersOnly);

    // Internal snap-to-guidelines funcs
    BOOL SnapToGuidelines(DocRect* pDocRect,const DocCoord& PrevCoord,const DocCoord& CurCoord);
    BOOL SnapToGuidesInLayer(Layer* pLayer,DocCoord* pDocCoord,GuidelineType Type);

    // Internal snap-to-guide-objects funcs
    BOOL SnapToGuideObjects(DocCoord* pDocCoord);
    BOOL SnapToGuideObjects(DocRect* pDocRect,const DocCoord& PrevCoord,const DocCoord& CurCoord);

    // Internal snap-to-pages funcs
    BOOL SnapToPages(DocCoord* pDocCoord);
    BOOL SnapToPages(DocRect* pDocRect,const DocCoord& PrevCoord,const DocCoord& CurCoord);

    // Internal snap-to-value function
    static BOOL SnapToValue(const INT32 RefValue, INT32* pTestValue, INT32* pLockedValue);

private:
    void CalcSnapDist();
    
    DocView*    pDocView;
    Spread*     pSpread;
    Node*       pLastSnappingObject;

    // This is how close a point needs to be to a shape before it can snap to it
    // It is relative to the scale factor of the CSnap object's DocView, and is calculated
    // when the CSnap object is constructed
    static MILLIPOINT SnapDist;
    static MILLIPOINT SnapToCoordDist;

    // This flag controls the snapping of points to the pages in the relevant spread
    // Page boundary snapping will only occur when 'snap to objects' is turned on.
    static BOOL TrySnapToPages;
};

#endif  // INC_SNAP

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