examples/Graphics/GraphicsShell/Zoom.cpp

// Copyright (c) 2000-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// License: "Symbian Foundation License v1.0" to Symbian Foundation
// members and "Symbian Foundation End User License Agreement v1.0"
// to non-members at the URL
// "http://www.symbianfoundation.org/legal/licencesv10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

#include "GraphicsControl.h"

// header for multi-bitmap file grbitmap.mbm containing 2 bitmaps to use
#include <grbmap2.mbg>

#include <coemain.h>

_LIT(KTxtCDrive,"\\");
_LIT(KTxtZDrive,"Z:");

void CZoomControl::LoadBitmapL(CFbsBitmap* aBitMap,const TDesC& aPathAndFile,TInt aId,TBool aShareIfLoaded)
        {
        TParse mbfn;
        
        mbfn.Set(aPathAndFile,&KTxtCDrive,NULL);
        if (!aBitMap->Load(mbfn.FullName(),aId,aShareIfLoaded))
                return;

        mbfn.Set(aPathAndFile,&KTxtZDrive,NULL);
        User::LeaveIfError(aBitMap->Load(mbfn.FullName(),aId,aShareIfLoaded));
        return;
        }

// Name of the multi-bitmap file containing the bitmap
// and bitmap mask files
_LIT(KTxtFileName,"\\resource\\apps\\grbmap2.mbm");

void CZoomControl::UpdateModelL()
        {
        // set up name for bitmap sharing
        TBool shareIfLoaded(ETrue);

        // set up two zoom factor objects (one for examples, one for commentary)
        iLeftZf.SetGraphicsDeviceMap(iCoeEnv->ScreenDevice());
        iRightZf.SetGraphicsDeviceMap(iCoeEnv->ScreenDevice());
        //iLeftZf.SetDevice(iCoeEnv->ScreenDevice());
        //iRightZf.SetDevice(iCoeEnv->ScreenDevice());
        
        // set the zoom factor of the objects (example is dependent on phase of example, commentary is fixed)
        iLeftZf.SetZoomFactor(TZoomFactor::EZoomOneToOne*2*(Phase()+1)/5);
        iRightZf.SetZoomFactor(TZoomFactor::EZoomOneToOne*2*(5-Phase())/5);

        // use graphics device maps for drawing and getting fonts
        iLeftMap=&iLeftZf;
        iRightMap=&iRightZf;

        if (Phase()==0) {
                iBitmap = new (ELeave) CFbsBitmap();
                LoadBitmapL(iBitmap,KTxtFileName,EMbmGrbmap2Smiley,shareIfLoaded);
        }
        
        // set up descriptor for commentary area
        _LIT(KFormat1,"Left zoom factor=%1.1f:1  Right zoom factor=%1.1f:1");
        TBuf<128> commentaryText;
        TReal leftValue = 2*(Phase()+1)/5.0;
        TReal rightValue = 2*(5-Phase())/5.0;
        commentaryText.Format(KFormat1,leftValue,rightValue);
        iGraphObserver->NotifyStatus(commentaryText);
        };

void CZoomControl::Draw(const TRect& /* aRect */) const
        {
        // setup screen for example: get graphics context and draw surrounding rectangle
        CWindowGc& gc=SystemGc();
        gc.Clear();     
        
        // create a centered rectangle of the default size
        TRect screenRect=Rect();
        TInt bisect = (screenRect.iBr.iX-screenRect.iTl.iX)/2 + screenRect.iTl.iX;
        TRect leftRect(screenRect.iTl,TPoint(bisect,screenRect.iBr.iY));
        TRect rightRect(TPoint(bisect,screenRect.iTl.iY),screenRect.iBr);

        DrawLeft(leftRect,gc);
        DrawRight(rightRect,gc);
        }


        _LIT(KTxtTimesNewRoman,"Times New Roman");
        _LIT(KTxtGrzoomExampleText,"grzoom example text");

void CZoomControl::DrawLeft(TRect screenRect,CWindowGc& SystemGc) const
        {
        // set up absolute font-spec and text box for 200 twip Times font
        TFontSpec fontSpec(KTxtTimesNewRoman,200);
        // find the nearest font to the specified one
        CFont* screenFont;                                                                              
        iLeftMap->GetNearestFontInTwips(screenFont,fontSpec);
        // use it for this graphics context
        SystemGc.UseFont(screenFont);
        // get height of screen box
    TInt screenHeight=screenRect.Height();
        // get font height
    TInt textHeight = screenFont->HeightInPixels();
        // 1/2 font height below halfway down box
    TInt exampleOffset=(screenHeight+textHeight)/2;
    TInt exampleMargin=0;
    SystemGc.DrawText(KTxtGrzoomExampleText,screenRect,exampleOffset,CGraphicsContext::ECenter,exampleMargin);
        // discard and release font
        SystemGc.DiscardFont();
        iLeftMap->ReleaseFont(screenFont);      
        
        // set up example box in twips
        TRect boxInTwips(TPoint(0,0),TPoint(500,300));
        // convert rectangle co-ordinates into pixels
        TRect boxInPixels = iLeftMap->TwipsToPixels(boxInTwips);
        SystemGc.DrawRect(boxInPixels);

        // set up rectangle for bitmap to be stretched into
        TRect bitmapRectInTwips(TPoint(0,0),TPoint(500,500));
        TRect bitmapRectInPixels = iLeftMap->TwipsToPixels(bitmapRectInTwips);
        bitmapRectInPixels.iTl.iY+=125;
        bitmapRectInPixels.iBr.iY+=125;
        bitmapRectInPixels.iTl.iX+=100;
        bitmapRectInPixels.iBr.iX+=100;
        // draw the bitmap, stretched into the rectangle
        SystemGc.DrawBitmap(bitmapRectInPixels, iBitmap);
        }

void CZoomControl::DrawRight(TRect screenRect,CWindowGc& SystemGc) const
        {
        // set up colors: black and a white RGB color
        TRgb black(0,0,0);
        TRgb white(255,255,255); // appears as blank screen gray-green color
    SystemGc.SetBrushStyle(CGraphicsContext::ESolidBrush);
    SystemGc.SetBrushColor(black);
    SystemGc.SetPenColor(white);

        // set up absolute font-spec and text box for 200 twip Times font
        TFontSpec fontSpec(KTxtTimesNewRoman,200);
        // find the nearest font to the specified one
        CFont* commentFont;
        iRightMap->GetNearestFontInTwips(commentFont,fontSpec);
        // use it for this graphics context
        SystemGc.UseFont(commentFont);
        // get font height
    TInt textHeight = commentFont->HeightInPixels();
    // get height of text box
    TInt boxHeight=screenRect.Height();
        // 1/2 font height below halfway down box
    TInt commentOffset=(boxHeight+textHeight)/2;
    TInt commentMargin=0;
        // draw text
    SystemGc.DrawText(KTxtGrzoomExampleText,screenRect,commentOffset,CGraphicsContext::ECenter,commentMargin);
        // discard and release font
        SystemGc.DiscardFont();
        iRightMap->ReleaseFont(commentFont);
        
        // set up example box in twips
        TRect boxInTwips(TPoint(0,0),TPoint(500,300));
        // convert rectangle co-ordinates into pixels
        TRect boxInPixels = iRightMap->TwipsToPixels(boxInTwips);
        boxInPixels.Move(screenRect.iTl);
        SystemGc.DrawRect(boxInPixels);

        // set up rectangle for bitmap to be stretched into
        TRect bitmapRectInTwips(TPoint(0,0),TPoint(500,500));
        TRect bitmapRectInPixels = iRightMap->TwipsToPixels(bitmapRectInTwips);
        bitmapRectInPixels.Move(screenRect.iTl);
        bitmapRectInPixels.iTl.iY+=125;
        bitmapRectInPixels.iBr.iY+=125;
        bitmapRectInPixels.iTl.iX+=100;
        bitmapRectInPixels.iBr.iX+=100;
        // draw the bitmap, stretched into the rectangle
        SystemGc.DrawBitmap(bitmapRectInPixels, iBitmap);
        }

---