gbrush.cpp

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// $Id: gbrush.cpp 1282 2006-06-09 09:46:49Z alex $
/* @@tag:xara-cn@@ DO NOT MODIFY THIS LINE
================================XARAHEADERSTART===========================
 
               Xara LX, a vector drawing and manipulation program.
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----------------------------------

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 */

// class to use raw to obtain GDI brush patterns


#include "camtypes.h"
#include "gbrush.h"
//#include "ensure.h"
#include "devcolor.h"
//#include "doccolor.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "fixmem.h" - in camtypes.h [AUTOMATICALLY REMOVED]
#include "grndrgn.h"
//#include "app.h"
#include "gbrushop.h"
//#include "andy.h"
//#include "docview.h"
//#include "ccolbar.h"
#include "gdrawcon.h"
#include "gdraw.h"
//#include "dibutil.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "palman.h"

CC_IMPLEMENT_MEMDUMP(GBrush, ListItem)
CC_IMPLEMENT_DYNCREATE(OpGBrush, Operation)
#define new CAM_DEBUG_NEW


List            GBrush::BrushList;                  // list of all active brushes
GBrush          *GBrush::Current;                   // current brush, or NULL
static BOOL WantBetterBrushes = TRUE;               // TRUE to use these, FALSE to not


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

    Preference: BetterBrushes
    Section:    Screen
    Range:      0 or 1
    Purpose:    Allows the user to determine whether GDraw brushes are used (1) or normal
                GDI brushes (0). Defaults to 1 because it produces a much nicer colour bar.

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

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

>   BOOL GBrush::InitGBrush( BOOL FirstTime )

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     FirstTime is TRUE if called from starup, FALSE if called subsequently (e.g.
                after screen mode change).
    Outputs:    -
    Returns:    TRUE if worked, FALSE if failed (e.g. no memory). Returns TRUE if not
                required too (e.g. incompatible screen depth) i.e. FALSE is an error which
                could be serious.
    Purpose:    GBuilds the pretend bitmap which ise used to fool GDraw into suppyling us
                with brushes. Called from GRenderRegion::Init and relies on that being called
                first.
    SeeAlso:    GBrush::Init
    Errors:     -
    Scope:      Static

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

BOOL GBrush::InitGBrush(BOOL FirstTime)
{
    if (FirstTime && Camelot.DeclareSection( wxT("Screen"), 10))
    {
        Camelot.DeclarePref(NULL, wxT("BetterBrushes"), &WantBetterBrushes, FALSE, TRUE );
    }
    // Register the (debug) Op to enable/disable GBrush
    if (!Operation::RegisterOpDescriptor(
                        0,
                        _R(IDS_GBRUSH),
                        CC_RUNTIME_CLASS(OpGBrush),
                        OPTOKEN_GBRUSH,
                        OpGBrush::GetState,
                        0,  /* help ID */
                        0, //_R(IDBBL_ANTIALIASOP),
                        0   /* bitmap ID */
                        ))
    {
        TRACE( wxT("RegisterOpDescriptor( OpGBrush ) failed") );
        return FALSE;
    }

    // Ensure that none of the GBrushes are active
    NewBrushState();
    Current = NULL;

    return TRUE;
}



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

>   void GBrush::DeinitGBrush(void)

    Author:     Jason_Williams (Xara Group Ltd) <camelotdev@xara.com>
    Created:    11/9/95

    Purpose:    De-initialises the GBrush pretend bitmap. Called on DeInit of GRenderRegion
                to shut down without a memory leak taking place.

    SeeAlso:    GBrush::InitGBrush

    Errors:     ERROR3 with graceful exit if there are GBrushes still active at the time

    Scope:      Static

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

void GBrush::DeinitGBrush(void)
{
#ifdef _DEBUG
    // This was an ERROR3, but our stupid error handler doesn't handle errors very well,
    // (in fact, at this stage in program de-initialisation, it doesn' handle them at all)
    // so it's just a trace warning now.
    if (!BrushList.IsEmpty())
    {
        TRACEALL( wxT("Warning: Deinitialising GBrush when GBrush(es) still active\n\n" ) );
    }
#endif
}


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

>   GBrush::GBrush()

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     -
    Outputs:    -
    Returns:    -
    Purpose:    GBrush constructor. Call Init before trying to use.
    SeeAlso:    GBrush::Init
    Errors:     -

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

GBrush::GBrush()
{
    CanUse = FALSE;
    Valid = FALSE;

    BrushList.AddHead( this );

    UseSolidColours = FALSE;
}



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

>   GBrush::~GBrush()

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     -
    Outputs:    -
    Returns:    -
    Purpose:    GBrush destructor. Does necessary cleanup.
    Errors:     -

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

GBrush::~GBrush()
{
    if (Current == this)
        Current = NULL;

#ifdef _DEBUG
    ListItem *Old = BrushList.RemoveItem( this );
    ERROR3IF( Old == NULL, "GBrush being deleted not in list" );
#else
    BrushList.RemoveItem( this ); // to suppress compiler warning in both debug & retail builds
#endif
}


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

>   BOOL GBrush::Init( HDC RefDC )

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     RefDC - an HDC of the output device (must be screen currently).
                This must remain a valid DC for the entire length of time that this
                brush is used.
    Outputs:    -
    Returns:    TRUE if GBrush is available for use, FALSE if not.
    Purpose:    Determines whether a GBrush can be used in the given device. Call Start
                before trying to use, assuming a TRUE result.
    Errors:     -

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

BOOL GBrush::Init( wxDC* RefDC )
{
    ENSURE( Current==NULL, "Only one current GBrush at a time" );

    Valid = FALSE;                                          // in case of failure

    ReferenceDC = RefDC;                                    // remember for Start time

    CanUse = TRUE;
    return CanUse;
}



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

>   void GBrush::Start()

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     -
    Outputs:    -
    Returns:    -
    Purpose:    Call before trying to use the GBrush. There can only be one active GBrush
                in use at a time. Will fail silently if not available.
    Errors:     GBrush::Available

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

void GBrush::Start()
{
    ENSURE( Current==NULL, "Only one current GBrush at a time" );

    if (CanUse && WantBetterBrushes)
    {
        GDrawContext *GContext = GRenderRegion::GetStaticDrawContext();

        // We checked this in Init() so it should be OK, but we might as well be safe
        if (GContext != NULL)
        {
            Valid = TRUE;
            Current = this;

            // Get the 16bpp screen hinting value so Gavin can do solid colours properly
            DWORD GavinHint = DIBUtil::GetGavinBlitFormat(GRenderRegion::ScreenDepth,
                                    32, GRenderRegion::ScreenHinting);

            // And set Gavin up to render into our brush bitmap
            GContext->SetupBitmap( 
                4,4, 
                GRenderRegion::ScreenDepth==24?32:GRenderRegion::ScreenDepth, 
                NULL, 
                GavinHint
            );

            // We want dithering not error diffusion please GDraw
            /*pcLOGPALETTE lpPal =*/ GContext->SelectPalette(0);

            // In 8bpp, make sure GDraw is aware of the current system palette
            if (GRenderRegion::ScreenDepth == 8)
                GRenderRegion::GColInit( ReferenceDC );

            // Attempt to ensure halftone patterns always use the same origin
            GContext->SetHalftoneOrigin(0, 0);
        }
        else
            ERROR3("GDraw Context not available in GBrush::Start()");
    }
}



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

>   void GBrush::Stop()

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     -
    Outputs:    -
    Returns:    -
    Purpose:    Says 'we have stopped using this for the moment'. Call Start to start again.
                It is not necessary to call this before destruction. Safe to call even if not
                Available.
    Errors:     -

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

void GBrush::Stop()
{
    if (Current == this)
        Current = NULL;

    Valid = FALSE;
}



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

>   inline void GBrush::GetLogBrushInternal( const COLORREF rgb, LPLOGBRUSH lpBrush )

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com> (Jason)
    Created:    5/4/94 (28/6/94)
    Inputs:     rgb - a GDI/GDraw style RGB word defining the colour
    Outputs:    lpBrush is updated to create a suitably brush which can then be passed
                to CreateBrushIndirect.
    Returns:    -
    Purpose:    The whole point of the GBrush class is to get one of these. This is an
                inline macro used by the 2 overloaded GetLogBrush functions so the code
                need only be changed in one place.

    Errors:     Will ENSURE if not Available.
    Notes:      This is fundametally the same as the other overloaded GetLogBrush,
                but for efficiency I've repeated the code in both functions.

                SetSolidColours should be called to enable/disable dithering of this brush

    SeeAlso:    GBrush::Available; GBrush::SetSolidColours

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

void GBrush::GetLogBrushInternal( const COLORREF rgb, wxBrush* pBrush )
{
    ERROR3IF( !Valid, "GBrush called when not available");
    ERROR3IF( Current != this, "GBrush not current");

    pBrush->SetStyle(wxSOLID);

    // we let the Widgets handle primary colours cos they should be able to manage it (!)
    if ( ((rgb & 0x0000FF)==0x000000 || (rgb & 0x0000FF)==0x0000FF) &&
         ((rgb & 0x00FF00)==0x000000 || (rgb & 0x00FF00)==0x00FF00) &&
         ((rgb & 0xFF0000)==0x000000 || (rgb & 0xFF0000)==0xFF0000) )
    {
        pBrush->SetColour(GetRValue(rgb),GetGValue(rgb),GetBValue(rgb));
        return;
    }

    // We assume the GBrush is defined in the GContext belonging to GRenderRegions
    // ARRRGGHHH Who wrote MakeCurrent() without making it Virtual. What a naughty
    // boy I am (Andy, that is! - Jason ;-)
    GDrawContext *GContext = GRenderRegion::GetStaticDrawContext();
    const BYTE *pGBrush = NULL;

    // This was checked in init/start, but we might as well be safe
    if (GContext != NULL)
    {
        // If the current mode is for solid colours (no dithering) then we ask for solid colour.
        // This is used for things like pasteboards which shouldn't dither for aesthetic (eor!) reasons
        if (UseSolidColours)
            GContext->SetSolidColour(rgb);
        else
            GContext->SetColour(rgb);

        pGBrush = GContext->ReturnBrushRGB();
    }
    else
        ERROR3("GBrush got a NULL GContext!\n");

    if (pGBrush == NULL)
        pBrush->SetColour(GetRValue(rgb),GetGValue(rgb),GetBValue(rgb));
    else if ( UseSolidColours )
        pBrush->SetColour(pGBrush[0],pGBrush[1],pGBrush[2]);
    else
    {
#ifdef __WXGTK__
        // The following line shouldn't be necessary, but wxGTK appears to
        // fail if it doesn't have a valid colour when setting the brush
        // into a device context.
        pBrush->SetColour(0,0,0);
#endif
        wxImage image(4,4,(BYTE*)pGBrush,true);
        wxBitmap bitmap(image);
        pBrush->SetStipple(bitmap);     // Also sets style to wxSTIPPLE
    }
}



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

>   void GBrush::SetSolidColours(BOOL SetSolid)

    Author:     Jason_Williams (Xara Group Ltd) <camelotdev@xara.com>
    Created:    15/5/95
    Inputs:     TRUE to turn off dithering of colours, FALSE to turn on dithering

    Purpose:    Allows the dithering of colours to be turned off so they look the same
                using GDraw as they do with the GDI.

    Notes:      By default, GBrushes use dithering.

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

void GBrush::SetSolidColours(BOOL SetSolid)
{
    UseSolidColours = SetSolid;
}



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

>   void GBrush::GetLogBrush( ColourContext *OutputContext, DocColour &Col,
                                LPLOGBRUSH lpBrush )

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    5/4/94
    Inputs:     OutputContext - The output colour context in which the DocColour
                is to be used.
                Col - colour that the brush is required in
    Outputs:    lpBrush is updated to create a suitably brush which can then be passed
                to CreateBrushIndirect.
    Returns:    -
    Purpose:    The whole point of the GBrush class is to get one of these.
    Errors:     Will ENSURE if not Available.
    SeeAlso:    GBrush::Available

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

void GBrush::GetLogBrush( ColourContext *OutputContext, DocColour &Col, wxBrush* pBrush )
{
    const COLORREF rgb = ConvertColourToScreenWord(OutputContext, &Col);

    GetLogBrushInternal(rgb,pBrush);
}



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

>   void GBrush::GetLogBrush( const COLORREF rgb, LPLOGBRUSH lpBrush )

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>/Jason
    Created:    5/4/94 (28/6/94)
    Inputs:     rgb - a GDI/GDraw style RGB word defining the colour
    Outputs:    lpBrush is updated to create a suitably brush which can then be passed
                to CreateBrushIndirect.
    Returns:    -
    Purpose:    The whole point of the GBrush class is to get one of these. This method
                returns a brush given the RGB screen word to use fo it. Probably you really
                want to use the other overloaded GetLogBrush method, as this does all the
                colour conversion for you.
    Errors:     Will ENSURE if not Available.
    SeeAlso:    GBrush::Available

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

void GBrush::GetLogBrush( const COLORREF rgb, wxBrush* pBrush )
{
    GetLogBrushInternal(rgb,pBrush);
}



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

>   void GBrush::NewBrushState()

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    28/7/94
    Inputs:     -
    Outputs:    -
    Returns:    -
    Purpose:    Called when the WantBetterBrushes state changes. Goes around and invalidates
                any current GBrushes, else they will be wrong.
                It also frees the global memory block in each GBrush so it will be
                re-allocated.

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

void GBrush::NewBrushState()
{
    // find all current GBrushes
    ListItem *Item = BrushList.GetHead();
    while (Item)
    {
        // check type
        #ifdef _DEBUG
        ENSURE( Item->GetRuntimeClass() == CC_RUNTIME_CLASS(GBrush), "Not GBrush in list");
        #endif

        // safe to cast now
        GBrush *const Brush = (GBrush*const)Item;
        Brush->Stop();                                  // reset Valid & Current

        // get next one in list
        Item = BrushList.GetNext( Item );
    }
}





// --- Operation to enable/disable GBrush plotting. Used only for debug purposes ---

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

>   void OpGBrush::Do(OpDescriptor*)

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    7/4/94
    Inputs:     None
    Outputs:    None
    Returns:    None
    Purpose:    Toggles state of GBrush flag then forces a redraw.
    Errors:     None

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

void OpGBrush::Do(OpDescriptor*)
{
    WantBetterBrushes ^= TRUE;

    // Iterate over all the documents, forcing a redraw of all the views.
    ListItem* pItem = Camelot.Documents.GetHead();
    while (pItem != NULL)
    {
        ((Document*) pItem)->ForceRedraw();
        pItem = Camelot.Documents.GetNext(pItem);
    }

    // invalidate current brushes
    GBrush::NewBrushState();

#ifndef STANDALONE
    // This is not likely to remain an interactively-alterable option,
    // so for now we just poke at the colour bar to make it redraw itself
    // in the new mode.
    PORTNOTETRACE("other","OpGBrush::Do - removed call to RedrawGBrushAreas");
#ifndef EXCLUDE_FROM_XARALX
    CColourBar::RedrawGBrushAreas();
#endif
    // We should also do this for galleries (e.g. colour gallery) but
    // as this can only be done in debug builds it's not worth the effort.
#endif

    End();
}



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

>   OpGBrush::OpGBrush()

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    7/4/94
    Inputs:
    Outputs:
    Returns:
    Purpose:    Constructor for OpGBrush operation. It is not undoable.
    Errors:     None

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

OpGBrush::OpGBrush()
{
}



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

>   OpState OpGBrush::GetState(String_256*, OpDescriptor*)

    Author:     Andy_Pennell (Xara Group Ltd) <camelotdev@xara.com>
    Created:    7/4/94
    Inputs:
    Outputs:
    Returns:
    Purpose:    This item is always available.
    Errors:     None

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

OpState OpGBrush::GetState(String_256*, OpDescriptor*)
{
    OpState OpSt;

    if (WantBetterBrushes)
        OpSt.Ticked = TRUE;

    return OpSt;
}

---