pbecomea.cpp

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// $Id: pbecomea.cpp 1361 2006-06-25 16:43:38Z alex $
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 */
//
// Implementation of PathBecomeA.
//

#include "camtypes.h"   // pre-compiled header.
#include "pbecomea.h"   // make shapes stuff.

#include "strkattr.h"   // AttrStrokeType use.
#include "ppstroke.h"

#include "nodepath.h"   // NodePath reference.
#include "lineattr.h"   // for line width & colour attributes.
#include "ndclpcnt.h"   // for ClipView path constants.
#include "attrmap.h"

DECLARE_SOURCE("$Revision: 1361 $");

// dynamic class creation stuff.
CC_IMPLEMENT_MEMDUMP(PathBecomeA, BecomeA)
CC_IMPLEMENT_MEMDUMP(ContourBecomeA2, PathBecomeA)

// Declare smart memory handling in Debug builds
#define new CAM_DEBUG_NEW



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

>   PathBecomeA::PathBecomeA(   BecomeAReason baReason, CCRuntimeClass* pClass,
                                UndoableOperation* pUndoOp, BOOL bSel, Path* pResultPath,
                                enum OutlineRules OutlineRule = IGNORE_OUTLINES )
    Author:     Karim_MacDonald (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10 February 2000
    Inputs:     baReason    the reason for the call to this function.
                pClass      the type of class required - ie a NodePath.
                pUndoOp     ptr to the Op requesting the BecomeA.
                bSel        whether to select the newly created node (unused in this class).
                pResultPath points to a Path object in which to leave the results.

                fRemoveOutlines     if set, then we strip the area obscured by any object
                                    outlines, from the resultant path.

    Outputs:    After a call to DoBecomeA with this parameter object, baReason set to
                BECOMEA_PASSBACK and pClass set to NodePath, pResultPath should contain the 
                outline(s) of whatever node was asked to DoBecomeA.

    Notes:      It is up to the caller to create, initialise and destroy the Path object 
                pointed to by pResultPath. All we do is fill the path object with the
                required information.

                Outline rules - as an example, imagine processing two overlapping circles
                with 20pt line width:
                IGNORE_OUTLINES     the default; result - the path which would enclose
                                    both circles if their line widths were set to 0.

                STRIP_OUTLINES      the path which would result if you drew the circles,
                                    then erased the areas covered by their thick line widths.

                ADD_OUTLINES        the path which would result if you drew the circles,
                                    complete with thick line widths.

********************************************************************************************/
PathBecomeA::PathBecomeA(   BecomeAReason baReason, CCRuntimeClass* pClass,
                            UndoableOperation* pUndoOp, BOOL bSel, Path* pResultPath,
                            enum OutlineRules OutlineRule )
                            : BecomeA(baReason, pClass, pUndoOp, bSel)
{
    // initialise our pointer to the result-path.
    m_pResultPath = pResultPath;

    // initialise our outlines behaviour.
    m_OutlineRule = OutlineRule;
    if (m_OutlineRule == STRIP_OUTLINES)
        m_ClipPathRule = 4;
    else if (m_OutlineRule == ADD_OUTLINES)
        m_ClipPathRule = 7;
}



PathBecomeA::~PathBecomeA()
{
    // empty our pointer to the result-path.
    m_pResultPath = NULL;
}



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

>   virtual BOOL PathBecomeA::Passback( NodeRenderableInk* pNewNode,
                                        NodeRenderableInk*& pCreatedByNode,
                                        CCAttrMap* pAttrMap = NULL)
    Author:     Karim_MacDonald (Xara Group Ltd) <camelotdev@xara.com>
    Created:    10 February 2000
    Inputs:     pNewNode        points to a new NodeRenderableInk created as a result of the 
                                BecomeA operation.
                pCreatedByNode  the node which called us.
                pAttrMap        an attribute map - useful for stroking paths...

    Returns:    TRUE if successful, FALSE otherwise.

    Purpose:    Called by DoBecomeA when a node is asked to convert itself to another type of 
                node. The passed-in new node is expected to be a NodePath. We extract its 
                actual Path, and add it to the path referenced by a pointer we were given at 
                construction.

    Notes:      The possible node tree pointed to by pNewNode, together with pAttrMap, must 
                both be destroyed by this function - no-one else is going to do it.

    Errors:     ERROR2 with FALSE if pNewNode is NULL or is not a path.
    See also:   BecomeA::PassBack()

********************************************************************************************/
BOOL PathBecomeA::PassBack( NodeRenderableInk* pNewNode,
                            NodeRenderableInk* pCreatedByNode,
                            CCAttrMap* pAttrMap )
{
    // validate inputs.
    ERROR2IF(   pNewNode == NULL || !pNewNode->IsNodePath(),
                FALSE,
                "PathBecomeA::PassBack; Passed back node was NULL, or not a path" );

    ERROR2IF(   m_pResultPath == NULL, FALSE,
                "PathBecomeA::PassBack; NULL result path!"  );

    BOOL fDeleteAttributes  = TRUE;
    BOOL fDeleteFillPath    = FALSE;

    const INT32 Flatness = NodeClipViewController::EstimatePathFlatness();

    // try to get an attribute map for converting the outline to shapes.
    if (pAttrMap == NULL)
    {
        fDeleteAttributes = FALSE;
        pAttrMap = CCAttrMap::MakeAppliedAttrMap(pCreatedByNode);
    }

    NodePath* pNewNodePath = (NodePath*)pNewNode;

    Path* pFillPath = &( pNewNodePath->InkPath );
    Path* pLinePath = NULL;

    // ok, first try to get the node's outline as a closed path.
    // we obviously won't get anything unless the outline's non-transparent.
    pLinePath = ExtractOutlineAsPath(pNewNodePath, pAttrMap);

    // providing the fill-path is filled, we'll use it as is.
    if (pFillPath->IsFilled)
    {
        if (pFillPath->GetNumCoords() < 3)
            pFillPath->ClearPath();
    }

    // if the fill-path is open, then we'll use the line path instead.
    else
    {
        fDeleteFillPath = TRUE;
        pFillPath = pLinePath;
        pLinePath = NULL;
    }

    // provided it exists, add the fill-path to the results path.
    if (pFillPath != NULL && pFillPath->GetNumCoords() > 0)
    {
        // if our results path is empty, just plonk the fill path in it.
        if (m_pResultPath->GetNumCoords() == 0)
            m_pResultPath->CloneFrom(*pFillPath);

        // otherwise, add our fill path to the current results path.
        // there's a slight optimisation here - if the bounds of the two paths don't overlap,
        // then the path union can be done simply by merging them together.
        else
        {
            BOOL fBoundsOverlap = FALSE;
            DocRect drResultPath(0, 0, 0, 0);
            DocRect drFillPath(0, 0, 0, 0);
            if (m_pResultPath->GetTrueBoundingRect(&drResultPath))
                if (pFillPath->GetTrueBoundingRect(&drFillPath))
                    if (drFillPath.IsIntersectedWith(drResultPath))
                        fBoundsOverlap = TRUE;

            if (!fBoundsOverlap)
                m_pResultPath->MergeTwoPaths(*pFillPath);

            else
            {
                m_pResultPath->ClipPathToPath(  *pFillPath, m_pResultPath, 7,
                                                NodeClipViewController::CLIPVIEW_TOLERANCE,
                                                Flatness,
                                                Flatness );

                // there is a bug here somewhere.  If pCreatedByNode just happens to have a stroke
                // applied to it, then the above call to ClipPathToPath seems to invert the path!
                // I'm not sure what to do about this, so for now it going to have to be left ....
                // NOTE:  to observe the bug, group two (overlapping) quickshapes, apply a stroke to
                // the group and slice with a line.
            }
        }
    }

    // if we're not ignoring outlines and we have a valid outline,
    // then throw it into the soup.
    if (m_OutlineRule != IGNORE_OUTLINES)
    {
        if (pLinePath != NULL)
        {
            m_pResultPath->ClipPathToPath(  *pLinePath, m_pResultPath, m_ClipPathRule | 0x10,
                                            NodeClipViewController::CLIPVIEW_TOLERANCE,
                                            Flatness,
                                            Flatness );
        }

        // a side-effect of the ClipPathToPath call above is that it ensures the path is tidy.
        // this ClipPathToPath call does the same thing.
        else
            m_pResultPath->ClipPathToPath(*m_pResultPath, m_pResultPath, 3, 20, 75, 75);
    }

    // PathBecomeA tries to return closed paths, so ensure our results path is marked so.
    if (!m_pResultPath->IsFilled)
        m_pResultPath->IsFilled = TRUE;

    // clear away all our temporary info.
    // no NULL assignments required, as these vars are all about to go out of scope.
    if (pLinePath != NULL)
        delete pLinePath;

    if (fDeleteFillPath && pFillPath != NULL)
        delete pFillPath;

    if (pAttrMap != NULL)
    {
        if (fDeleteAttributes)
            pAttrMap->DeleteAttributes();

        delete pAttrMap;
    }

    pNewNode->CascadeDelete();
    delete pNewNode;

    return TRUE;
}



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

>   Path* PathBecomeA::ExtractOutlineAsPath(NodePath* pSrcNodePath, CCAttrMap* pAttrMap)

    Author:     Karim_MacDonald (Xara Group Ltd) <camelotdev@xara.com>
    Created:    18/11/2000
    Inputs:     pSrcNodePath    a NodePath whose outline we're going to extract.
                pAttrMap        the attribute map from which we'll get line attributes,
                                eg width, cap style, join style etc.
    Returns:    A ptr to a path if successful,
                NULL otherwise.

    Purpose:    Given a NodePath and an attribute map, construct the Path which delineates
                the NodePath's outline. If the line width of the path is 0pt, you'll get
                a NULL ptr back.

    Notes:      This method returns a Path allocated on the heap - it's *your* responsibility
                to delete it!

                Either input can be NULL, in which case you'll get a NULL ptr back.

                This method should really just take a pure Path* for flexibility,
                however we make use of MakeNodePathFromAttributes(), which is a NodePath
                method. I'm fed up of rewriting other people's code at the moment and
                I don't want to potentially destabilise the code base before a release.
                If you want to rewrite MakeNodePath... and this method to take a pure Path*,
                be my guest :o)

********************************************************************************************/
Path* PathBecomeA::ExtractOutlineAsPath(NodePath* pSrcNodePath, CCAttrMap* pAttrMap)
{
    // we can accept NULL inputs - we just don't do any processing for them.
    if (pAttrMap == NULL || pSrcNodePath == NULL)
        return NULL;

    const INT32 Flatness = NodeClipViewController::EstimatePathFlatness();

    Path* pFillPath     = &( pSrcNodePath->InkPath );
    Path* pStrokePath   = NULL;

    // we only need to generate an outline path if the path has non-transparent line colour.
    BOOL bHaveAnOutline = FALSE;
    AttrStrokeColour* pAttrStrokeColour = NULL;
    pAttrMap->Lookup( CC_RUNTIME_CLASS(AttrStrokeColour), (void*&)pAttrStrokeColour );
    if (pAttrStrokeColour != NULL)
    {
        DocColour* pLineColour = pAttrStrokeColour->GetStartColour();
        if (pLineColour != NULL && !pLineColour->IsTransparent())
        {
            bHaveAnOutline = TRUE;
        }
    }

    // ok, if we don't have an outline, then go home now.
    if (!bHaveAnOutline)
        return NULL;

    // if the line is stroked, then use the stroke's path-processor to give us the outline.
    AttrStrokeType* pAttrStrokeType = NULL;
    pAttrMap->Lookup( CC_RUNTIME_CLASS(AttrStrokeType), (void*&)pAttrStrokeType );
    if (pAttrStrokeType != NULL && pAttrStrokeType->HasPathProcessor())
    {
        PathProcessorStroke* pPPS = pAttrStrokeType->GetPathProcessor();
        if (pPPS != NULL)
        {
            pStrokePath = pPPS->GetProcessedPath(pFillPath, pAttrMap);
            pStrokePath->ClipPathToPath(*pStrokePath, pStrokePath, 3 | 0x10, 20, 75, 75);
        }
    }

    // if it's a simple line, then use DavidMc's MakeNodePath... method.
    else
    {
        NodePath* pNodeOutline = NULL;
        pNodeOutline = pSrcNodePath->MakeNodePathFromAttributes(Flatness,
                                                                pAttrMap,
                                                                TRUE);
        if (pNodeOutline != NULL)
        {
            pStrokePath = pNodeOutline->GetPathCopy();
            delete pNodeOutline;
            pNodeOutline = NULL;
        }
    }

    return pStrokePath;
}



//-------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------



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

>   ContourBecomeA2::ContourBecomeA2(   UndoableOperation* pUndoOp,
                                        MILLIPOINT Width,
                                        Path* pResultPath   )
    Author:     Karim_MacDonald (Xara Group Ltd) <camelotdev@xara.com>
    Created:    21/11/2000
    Inputs:     pUndoOp         pointer to an Op, if you have one.
                Width           how far out you want me to contour, in millipoints.
                pResultPath     where you want me to plonk the contour - must point to
                                an initialised path which you don't mind me emptying.

    Purpose:    Constructor for a new ContourBecomeA, to do your contouring dirty work :o)

********************************************************************************************/
ContourBecomeA2::ContourBecomeA2(   UndoableOperation* pUndoOp,
                                    MILLIPOINT Width,
                                    Path* pResultPath   )
                                    : PathBecomeA(  BECOMEA_PASSBACK,
                                                    CC_RUNTIME_CLASS(NodePath),
                                                    pUndoOp,
                                                    FALSE,
                                                    pResultPath,
                                                    ADD_OUTLINES )
{
    m_Width = Width;
    SetDoSilhouette(TRUE);
    SetDoShadowSilhouettes(TRUE);
}



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

>   BOOL ContourBecomeA2::PassBack( NodeRenderableInk* pNewNode,
                                    NodeRenderableInk* pCreatedByNode,
                                    CCAttrMap* pAttrMap )
    Author:     Karim_MacDonald (Xara Group Ltd) <camelotdev@xara.com>
    Created:    21/11/2000

    Inputs:     pNewNode        ptr to the NodePath which you're passing in to me
                                (don't expect it back).
                pCreatedByNode  ptr to the node which created the NodePath - useful to me
                                if you don't supply an attr-map.
                pAttrMap        ptr to an attr-map for me to get line attributes out of
                                when I stroke the path. Not compulsory

    Outputs:    pResultPath will contain the result of doing a contour outwards from the
                DoBecomeA-ing objects.

    Returns:    TRUE if successful, FALSE if not.

    Purpose:    PassBack function fer lettin' me do ma contour thang.

********************************************************************************************/
BOOL ContourBecomeA2::PassBack( NodeRenderableInk* pNewNode,
                                NodeRenderableInk* pCreatedByNode,
                                CCAttrMap* pAttrMap )
{
    Path* pContourPath          = NULL;
    Path* pSummedContourPath    = m_pResultPath;

    m_pResultPath = new Path;
    BOOL    ok = (m_pResultPath != NULL);
    if (ok) ok = m_pResultPath->Initialise();
    if (ok)
    {
        PathBecomeA::PassBack(pNewNode, pCreatedByNode, pAttrMap);
        ok = (m_pResultPath->GetNumCoords() != 0);
    }
    if (ok)
    {
        pContourPath = new Path;
        ok = (pContourPath != NULL);
    }
    if (ok) ok = pContourPath->Initialise();
    if (ok)
    {
        TRACEUSER( "Karim", _T("Node at 0x%x; ResultPath - %d coords.\n"),
                            pCreatedByNode,
                            m_pResultPath->GetNumCoords());

        m_pResultPath->InitializeContourValues(2 * m_Width);
        m_pResultPath->GetContourForStep(pContourPath);

        delete m_pResultPath;
        m_pResultPath = pSummedContourPath;

        if (pContourPath->GetNumCoords() != 0)
            pContourPath->ClipPathToPath(*m_pResultPath, m_pResultPath, 7, 20, 75, 75);

        if (!m_pResultPath->IsFilled)
            m_pResultPath->IsFilled = TRUE;

        delete pContourPath;
    }

    return ok;
}

---