ai_grad.cpp

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// $Id: ai_grad.cpp 1313 2006-06-13 16:55:22Z alex $
// ai_grad.cpp: implementation of the AIGradientProcessor class.
//
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 */

#include "camtypes.h"
#include "ai_grad.h"

#include "ai5_eps.h"
#include "fillramp.h"

DECLARE_SOURCE("$Revision");

#define new CAM_DEBUG_NEW

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

>   AI5Gradient::AI5Gradient()

    Author:     Tim_Browse (Xara Group Ltd) <camelotdev@xara.com>
    Created:    12/08/94
    Purpose:    Set up a gradient record to sensible values (linear fill black to black).
    SeeAlso:    AI5Gradient; AI5EPSFilter

********************************************************************************************/
AI5Gradient::AI5Gradient() :
    IsRadial( FALSE ),
    StartColour( BLACK ),
    EndColour( BLACK ),
    mpCurrentRamp( 0 )
{
}


AI5Gradient::~AI5Gradient()
{
    delete mpCurrentRamp;
    mpCurrentRamp = 0;
}






// Construction/Destruction

AIGradientProcessor::AIGradientProcessor() :
    mbGradFillTooComplex(FALSE),
    mpCurrentFill(0)
{
    // The last ramp point is set to 101, since this is effectively a
    // counter from 100 down to 0.
    mMidPoint       = 0;
    mLastRampPoint  = 101;
}

AIGradientProcessor::~AIGradientProcessor()
{
    mGradFills.DeleteAll();

    delete mpCurrentFill;
    mpCurrentFill = 0;
}


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

>   BOOL AIGradientProcessor::BeginGradient()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    23/03/00

    Purpose:    Allows the gradient processor to intialize itself for a new gradient
                signalled by the %BeginGradient comment.

    Returns:    TRUE if the definition was processed, 
                FALSE if not used by this filter..

********************************************************************************************/
BOOL AIGradientProcessor::BeginGradient()
{
    ENSURE( mpCurrentFill == NULL, "mpCurrentFill is not NULL");

    // Found the start of a gradient definition - prepare to read in the
    // definition...
    mpCurrentFill = new AI5Gradient;

    if ( !mpCurrentFill )
        return FALSE;

    return TRUE;
}



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

>   BOOL AIGradientProcessor::DecodeBd( AI5EPSFilter& filter )

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    23/03/00

    Purpose:    Processes the gradient definition start operator which tells us how many
                colours are in it and what its name is.

    Returns:    TRUE if the definition was processed, 
                FALSE if not used by this filter..

********************************************************************************************/
BOOL AIGradientProcessor::DecodeBd( AI5EPSFilter& filter )
{
    if ( !mpCurrentFill )
        return FALSE;

    // Name, type, and number of steps in gradient fill
    INT32 colours = 0;
    INT32 type = 0;

    if (!filter.GetStack().Pop(&colours) || 
        !filter.GetStack().Pop(&type) || 
        !filter.GetStack().Pop(&mpCurrentFill->Name))
        // Error in syntax
        return FALSE;

    // Translate fill type
    switch (type)
    {
        case 0:     mpCurrentFill->IsRadial = FALSE;    break;
        case 1:     mpCurrentFill->IsRadial = TRUE;     break;
        default:    return FALSE;
    }

    return TRUE;
}

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

>   BOOL AIGradientProcessor::DecodeBS( AI5EPSFilter& filter )

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    23/03/00

    Purpose:    Processes the gradient stop operator (indicating a step in the ramp)

    Returns:    TRUE if the definition was processed, 
                FALSE if not used by this filter..

********************************************************************************************/
BOOL AIGradientProcessor::DecodeBS( AI5EPSFilter& filter )
{
    // Decode colour/step definition
    INT32 rampPoint = 0, midPoint = 0;

    if ( !filter.GetStack().Pop(&rampPoint) || !filter.GetStack().Pop(&midPoint) )
        return FALSE;

    // Check if these are values we can handle
    // (We still import an approximation of the fill even if not)
    if ( midPoint > 100 || midPoint < 0 || rampPoint < 0 || rampPoint > 100 )
    {
        return FALSE;
    }

    // Work out what sort of colour this is - CMYK or B&W tint
    INT32 colorStyle;
    if ( !filter.GetStack().Pop(&colorStyle) )
        return FALSE;

    DocColour newColour;

    switch ( colorStyle )
    {
        case 0:     // grey
        {
            double dTint( 0.0 );
            if ( !filter.GetStack().Pop(&dTint) )
                return FALSE;

            // Make a colour from this
            INT32 intensity = (INT32) (dTint * 255.0);
            newColour.SetRGBValue( intensity, intensity, intensity );
            break;
        }

        case 1:     // CMYK
        {
            PColourCMYK col;
            if (!filter.GetStack().PopColour(&col, TINT_NONE))
                return FALSE;

            // Set up the colour with what we have.
            newColour.SetCMYKValue( &col );

            break;
        }

        case 2:     // RGB
        {
            INT32 red, green, blue;
            if (!filter.GetStack().PopColourRGB (&red, &green, &blue, TINT_NONE))
                return FALSE;

                // remove the CMYK colour info.
            (filter.GetStack()).Discard (4);
            newColour.SetRGBValue (red, green, blue);
            break;
        }

        case 3:     // CMYK custom
        {
            PColourCMYK col;
            FIXEDPOINT tint;
            String_64 name;
            if ( !filter.GetStack().PopColour( &col, TINT_ILLUSTRATOR, &tint, &name ) )
                return FALSE;

            newColour.SetCMYKValue( &col );

            break;
        }

        case 4:     // RGB custom
        {
            INT32 red, green, blue;
            FIXEDPOINT tint;
            String_64 name;

            // remove the 'type' flag (is always 1 for RGB)
            filter.GetStack().Discard (1);

            if (!filter.GetStack().PopColourRGB (&red, &green, &blue, 
                                                TINT_ILLUSTRATOR, &tint, &name))
                return FALSE;

            (filter.GetStack()).Discard (4);
            newColour.SetRGBValue (red, green, blue);

            break;
        }
        default:
            break;
    }


    //  add the colour to the ramp

    double dPos = double(rampPoint) / double(100.0);

    if ( mpCurrentFill )
    {
        if ( !mpCurrentFill->mpCurrentRamp )
        {
            mpCurrentFill->mpCurrentRamp = new ColourRamp;
            if ( ! mpCurrentFill->mpCurrentRamp )
            {
                return FALSE;
            }
        }

        mpCurrentFill->mpCurrentRamp->AddEntry( static_cast<float> ( dPos ), &newColour );
    }

    // Set the midpoint if this point is nearer to the start than the stored mid-point. 
    //  The midpoint nearest to the 0% ramp point is used, as there should only be one 
    //  midpoint if Xara X's profiling is going to cope with it, and the last midpoint in 
    //  an Illustrator gradient should always be ignored.
    if (rampPoint < mLastRampPoint)
    {
        mMidPoint = midPoint;
        mLastRampPoint = rampPoint;
    }

    return TRUE;
}


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

>   BOOL AIGradientProcessor::DecodeBh( AI5EPSFilter& filter )

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    23/03/00

    Purpose:    The Bh operator adds a highlight to a fill. In Camelot we interpret this
                as a conical fill.

    Returns:    TRUE if the definition was processed happily
                FALSE if not


    The format of the operator is:
        xHilight yHilight angle length Bh

    Arguments to the Bh operator are as follows:
        xHilight yHilight   These arguments specify the hilight placement, in x and y offsets 
                            from the gradient vector origin.
        angle               This argument is the angle to the hilight point, measured 
                            counterclockwise from the x axis.
        length              This argument is the distance of the hilight from the origin, 
                            expressed as a fraction of the radius a value between 0 and 1.


********************************************************************************************/
BOOL AIGradientProcessor::DecodeBh( AI5EPSFilter& filter )
{
    // read the arguments from the stack

    INT32 nAngle        = 0;
    double dLength  = 0.0;
    DocCoord hilight;

    if ( !filter.GetStack().Pop(&dLength) || !filter.GetStack().Pop(&nAngle) ||
        !filter.GetStack().PopCoordPair(&hilight) )
        return FALSE;

    // Check if these are values we can handle

    // Attach the highlight details so we can work out what to do later
    // but if there's already a highlight ignore this one
/*

  Won't do this for now


    mpCurrentHighlight = new AI5Gradient::Highlight( nAngle, dLength, hilight );
*/
    return TRUE;
}

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

>   BOOL AIGradientProcessor::Approx (const double & d1, const double & d2)

    Author:     ?
    Created:    presumably March 2000
    Inputs:     d1, d2 - two doubles that are to be compared
    Purpose:    This is used to determine whether the position of one gradient stop is 
                equivalent to another during import, mainly for working out which stops
                are at the start and the end.

                Currently the tolerance for this is 2% either way, as this seems to give
                good results.

    Returns:    TRUE if the d1 is approximately equal to d2
                FALSE if not

********************************************************************************************/
BOOL AIGradientProcessor::Approx (const double & d1, const double & d2)
{
    const double dTolerance = 2;
    return ( fabs( d2 - d1 ) < dTolerance );
}


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

>   BOOL AIGradientProcessor::EndGradient()

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    23/03/00

    Purpose:    Allows the gradient processor to complete the gradient
                signalled by the %EndGradient comment.

    Returns:    TRUE if the definition was processed, 
                FALSE if not used by this filter..

********************************************************************************************/
BOOL AIGradientProcessor::EndGradient( AI5EPSFilter& filter )
{
    ENSURE( mpCurrentFill != NULL, "mpGradFill is NULL");

    // The end of the definition - lose the rampant '[' from the input stream.
    EPSCommand Cmd;
    if (!filter.GetStack().PopCmd(&Cmd) || (Cmd != EPSC_ArrayStart))
    {
        // if it isn't what we're hoping for, ignore it
        filter.GetStack().Push( Cmd );
    }

    // an n-stage multi-stage fill in camelot is divided into n - 2 ramp items
    // and the start and end colours of the fill.
    // When creating the fill we have just added ramp items, so we need to pick 
    // off the first and last for the start and end colours.

    if ( mpCurrentFill->mpCurrentRamp )
    {   
        // (ChrisG 3/4/2001) Gradient stops are now always removed from the list if they are
        //  used as a start or end colour. There was a check to make sure they were near the
        //  end, which often failed, leading to additional stops at the ends.

        // first the start colour
        ColRampItem* pFirstItem = reinterpret_cast<ColRampItem*>( mpCurrentFill->mpCurrentRamp->GetHead() );
        if ( pFirstItem )
        {
            // Take the first colour out of the ramp, as this is represented by the start colour
            mpCurrentFill->StartColour = pFirstItem->GetColour();

            // if the first ramp item isn't at the start of the fill, leave it as
            // part of the ramp and make the start the same colour
            if ( Approx( pFirstItem->GetPosition(), 0.0) ||
                 Approx( pFirstItem->GetPosition(), 100.0))
            {
                mpCurrentFill->mpCurrentRamp->RemoveHead();
            }
        }

        // then the end colour
        ColRampItem* pLastItem = reinterpret_cast<ColRampItem*>( mpCurrentFill->mpCurrentRamp->GetTail() );
        if ( pLastItem )
        {
            // Take the last colour out of the ramp, as this is represented by the end colour
            mpCurrentFill->EndColour = pLastItem->GetColour();

            // if the first ramp item isn't at the start of the fill, leave it as
            // part of the ramp and make the start the same colour
            if ( Approx( pLastItem->GetPosition(), 0.0) ||
                 Approx( pLastItem->GetPosition(), 100.0))
            {
                mpCurrentFill->mpCurrentRamp->RemoveTail();
            }
        }
    }

    // set the mid-point, for the profiling.
    mpCurrentFill->midPoint = mMidPoint;

    // add the current fill to our list.
    mGradFills.AddTail( mpCurrentFill );

    // We're done with this fill.
    mpCurrentFill = NULL;

    // reset the profiling variables.
    mMidPoint       = 0;
    mLastRampPoint  = 101;

    return TRUE;
}


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

>   AI5Gradient* AIGradientProcessor::FindGradient( const StringBase& name )

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    23/03/00

    Purpose:    Once the gradient definitions have been read, gradient instances can be
                created using the name to identify the gradient "style".

    Returns:    NULL if no gradient exists with the given name
                Otherwise the one that does.

********************************************************************************************/
AI5Gradient* AIGradientProcessor::FindGradient( const StringBase& name )
{
    // First find this named gradient fill
    AI5Gradient* pGradient = (AI5Gradient *) mGradFills.GetHead();

    while ( pGradient )
    {
        if ( pGradient->Name == name )
            // This is the one we want!
            break;

        // Try the next one
        pGradient = (AI5Gradient *) mGradFills.GetNext(pGradient);
    }

    return pGradient;
}

---