graphicslabappview.cpp

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/*
* ============================================================================
*  Name     : CGraphicsLabAppView from CGraphicsLabAppView.h
*  Part of  : GraphicsLab
*  Created  : 10/14/2002 by 
*  Implementation notes:
*     Initial content was generated by Series 60 AppWizard.
*  Version  :
*  Copyright: 
* ============================================================================
*/

// INCLUDE FILES
#include "GraphicsLabAppView.h"
#include "bitmapmethods.h"
#include "sprite.h"
#include <graphicslab.mbg>

_LIT (KMultiBitmapFilename,"c:\\System\\Apps\\Graphicslab\\graphicslab.mbm"); // multi bitmap file
_LIT (KBounceCounter,"Number of bounces : "); // Text string for display

static const TInt KMaxDisplayString = 256; // buffer size for string

// these values can easily be changed if required
// note that animation appears much faster on the handset than in the emulator
static const TInt KInitialSpeed = 4;       // slow ball speed
static const TInt KFastSpeed = 8;          // fast ball speed
static const TInt KMaxNumBounces = 99;     // max number of bounces before animation stops
static const TInt KTimerIntervalMicroSeconds = 50000;

// ================= MEMBER FUNCTIONS =======================

// ---------------------------------------------------------
// CGraphicsLabAppView::ConstructL(const TRect& aRect)
// EPOC two phased constructor
// ---------------------------------------------------------
//

// Standard Epoc construction sequence
CGraphicsLabAppView* CGraphicsLabAppView::NewL(const TRect& aRect)
    {
    CGraphicsLabAppView* self = CGraphicsLabAppView::NewLC(aRect);
    CleanupStack::Pop();
    return self;
    }

CGraphicsLabAppView* CGraphicsLabAppView::NewLC(const TRect& aRect)
    {
    CGraphicsLabAppView* self = new (ELeave) CGraphicsLabAppView;
    CleanupStack::PushL(self);
    self->ConstructL(aRect);
    return self;
    }


void CGraphicsLabAppView::ConstructL(const TRect& aRect)
    {
    // Create a window for this application view
    CreateWindowL();

    // Set the window's size and position
    SetRect(aRect);

    // Load in the bitmap images from the multi bitmap file 
    iBackground = NBitmapMethods::CreateBitmapL(KMultiBitmapFilename,EMbmGraphicslabBackground);
    iBallImage = NBitmapMethods::CreateBitmapL(KMultiBitmapFilename,EMbmGraphicslabBall);
    iBallMask = NBitmapMethods::CreateBitmapL(KMultiBitmapFilename,EMbmGraphicslabBall_mask);
    iOtherBallImage = NBitmapMethods::CreateBitmapL(KMultiBitmapFilename,EMbmGraphicslabOther_ball);
    iOtherBallMask = NBitmapMethods::CreateBitmapL(KMultiBitmapFilename,EMbmGraphicslabOther_ball_mask);
    // Create the off screen bitmap and device / gc
    iOffScreenBitmap = NBitmapMethods::CreateBitmapL(Rect().Size(),KColourDepth);
    iOffScreenBitmapDevice = NBitmapMethods::CreateBitmapDeviceL(*iOffScreenBitmap);
    iOffScreenBitmapGc = NBitmapMethods::CreateGraphicsContextL(*iOffScreenBitmapDevice);

    // Create a periodic timer but don't start it yet
    iPeriodicTimer = CPeriodic::NewL(CActive::EPriorityStandard);

    //Create an array of sprite pointers for other ball sprites
    iOtherSprites = new (ELeave) CArrayPtrFlat<CSprite> (2);

    // set up sprites
    SetUpSpritesL();
    
    // set position on screen for text (bounce count) to appear
    iTextDisplay = Rect().iTl + TPoint(1,12);

    // Create font
    TTypefaceSupport myTypefaceSupport;
    iOffScreenBitmapDevice->TypefaceSupport(myTypefaceSupport,1);
    TFontSpec fontspec1(myTypefaceSupport.iTypeface.iName.Des(), 100);
    User::LeaveIfError(iOffScreenBitmapDevice->GetNearestFontInTwips(iFont, fontspec1));
    
    // Activate the window, which makes it ready to be drawn
    ActivateL();
    }

CGraphicsLabAppView::CGraphicsLabAppView()
    {
    }

// Destructor
CGraphicsLabAppView::~CGraphicsLabAppView()
    {
    if (iPeriodicTimer)
        {
        // Stop the periodic timer
        iPeriodicTimer->Cancel();
        }
    delete iPeriodicTimer;
    iPeriodicTimer = NULL;

    delete iOffScreenBitmapGc;
    iOffScreenBitmapGc = NULL;

    delete iOffScreenBitmapDevice;
    iOffScreenBitmapDevice = NULL;

    delete iOffScreenBitmap;
    iOffScreenBitmap = NULL;

    delete iBackground;
    iBackground = NULL;

    delete iMySprite;
    iMySprite = NULL;

    if (iOtherSprites)
        {
        iOtherSprites->ResetAndDestroy();
        delete iOtherSprites;
        iOtherSprites = NULL;
        }

    delete iBallImage;
    iBallImage = NULL;

    delete iBallMask;
    iBallMask = NULL; 

    delete iOtherBallImage;
    iOtherBallImage = NULL;

    delete iOtherBallMask;
    iOtherBallMask = NULL;  
    }

void CGraphicsLabAppView::SetUpSpritesL()
    {
    CSprite* sprite = NULL;

    // start the player's ball right in the middle of the screen
    TInt ballXPos = iBackground->SizeInPixels().iWidth/2 -
                    iBallImage->SizeInPixels().iWidth/2;
    TInt ballYPos = iBackground->SizeInPixels().iHeight/2 - 
                    iBallImage->SizeInPixels().iHeight/2;

    //Create the player's ball sprite
    sprite = CSprite::NewLC(KInitialSpeed,KInitialSpeed,Rect().iTl + TPoint(ballXPos, ballYPos));
    iMySprite = sprite;
    CleanupStack::Pop(sprite);

    // and the other ball sprites.....
    sprite = CSprite::NewLC(KInitialSpeed,-KInitialSpeed,Rect().iBr - iBallImage->SizeInPixels());
    iOtherSprites->AppendL(sprite);
    CleanupStack::Pop(sprite);  

    sprite = CSprite::NewLC(-KInitialSpeed,KInitialSpeed,Rect().iTl);
    iOtherSprites->AppendL(sprite);
    CleanupStack::Pop(sprite);  

    // ....could add as many as you like

    }

// ---------------------------------------------------------
// CGraphicsLabAppView::Draw(const TRect& aRect) const
// ---------------------------------------------------------
//
void CGraphicsLabAppView::Draw(const TRect& /* aRect */) const
    {
    // The system GC will already be activated when this function is called by the framework
    UpdateDisplay();
    }

void CGraphicsLabAppView::UpdateDisplay() const
    {
    CWindowGc& gc = SystemGc();

    // Blit the background image onto the off screen bitmap at the top left position
    iOffScreenBitmapGc->BitBlt(TPoint(0,0),iBackground);    

    // Blit the other ball sprites on top of it
    for (TInt count = 0; count < iOtherSprites->Count(); count++)
        {
        NBitmapMethods::BitBltMaskedEntireBitmap(*iOffScreenBitmapGc,
                                                 iOtherSprites->At(count)->Position(),
                                                 *iOtherBallImage,*iOtherBallMask);
        }
    // Blit my ball sprite on last
    NBitmapMethods::BitBltMaskedEntireBitmap(*iOffScreenBitmapGc, iMySprite->Position(),
                                             *iBallImage, *iBallMask);
    
    // Blit the offscreen image onto the screen at the top left position
    gc.BitBlt(Rect().iTl,iOffScreenBitmap); 
    
    // check if the ball has reached max allowed bounces
    if(iMySprite->GetBounceCount() > KMaxNumBounces)
        {
        // stop animation and reset counter to 0
        StopAnimation();
        iMySprite->SetBounceCount(0);
        }

    // create a string to display the current number of bounces
    _LIT (KFormatString,"%02d");
    TBuf<KMaxDisplayString> DisplayString;
    DisplayString.Format(KFormatString, iMySprite->GetBounceCount());
    
    iOffScreenBitmapGc->SetPenColor(TRgb(0xFFFFFF));
    // select font
    iOffScreenBitmapGc->UseFont(iFont);
    // write text to screen
    iOffScreenBitmapGc->DrawText(KBounceCounter, TPoint(iTextDisplay));
    // get width of text in pixels
    TInt Width = iFont->TextWidthInPixels(KBounceCounter);
    // reset pen colour for numbers
    iOffScreenBitmapGc->SetPenColor(TRgb(0xFFFF00));
    // draw figures next to the text
    iOffScreenBitmapGc->DrawText(DisplayString,  TPoint(iTextDisplay.iX + Width, iTextDisplay.iY));
    // discard the font 
    iOffScreenBitmapGc->DiscardFont();  
    }


TKeyResponse CGraphicsLabAppView::OfferKeyEventL(const TKeyEvent& aKeyEvent, TEventCode aType)
    {
    if((aType != EEventKeyDown) && (aType != EEventKey) && (aType != EEventKeyUp))
        {
        // ignore other events 
        return EKeyWasNotConsumed;
        }

    if(aKeyEvent.iCode == EKeyOK)
        {
        // change ball speed in X direction
        if(iMySprite->GetXVelocity() == KInitialSpeed) 
            {
            iMySprite->SetXVelocity(KFastSpeed);
            }
        else if (iMySprite->GetXVelocity() == -KInitialSpeed) 
            {
            iMySprite->SetXVelocity(-KFastSpeed);
            }
        else if (iMySprite->GetXVelocity() == KFastSpeed)
            {
            iMySprite->SetXVelocity(KInitialSpeed);
            }
        else
            {
            iMySprite->SetXVelocity(-KInitialSpeed);
            }
        // and in Y direction
        if(iMySprite->GetYVelocity() == KInitialSpeed) 
            {
            iMySprite->SetYVelocity(KFastSpeed);
            }
        else if (iMySprite->GetYVelocity() == -KInitialSpeed) 
            {
            iMySprite->SetYVelocity(-KFastSpeed);
            }
        else if (iMySprite->GetYVelocity() == KFastSpeed)
            {
            iMySprite->SetYVelocity(KInitialSpeed);
            }
        else
            {
            iMySprite->SetYVelocity(-KInitialSpeed);
            }
        }
    else if(aKeyEvent.iCode == EKeyLeftArrow)
        {
        if(iMySprite->GetXVelocity() > 0)
            {
            // change X velocity so ball is moving left
            iMySprite->SetXVelocity(-(iMySprite->GetXVelocity()));
            }
        else
            {
            return EKeyWasNotConsumed;
            }
        }
    else if(aKeyEvent.iCode == EKeyRightArrow)
        {
        if(iMySprite->GetXVelocity() < 0)
            {
            // change X velocity so ball is moving right
            iMySprite->SetXVelocity(-(iMySprite->GetXVelocity()));
            }
        else
            {
            return EKeyWasNotConsumed;
            }
        }
    else if(aKeyEvent.iCode == EKeyUpArrow) 
        {
        if(iMySprite->GetYVelocity() > 0)
            {
            // change Y velocity so ball is moving up
            iMySprite->SetYVelocity(-(iMySprite->GetYVelocity()));
            }
        else
            {
            return EKeyWasNotConsumed;
            }
        }
    else if(aKeyEvent.iCode == EKeyDownArrow)
        {
        if(iMySprite->GetYVelocity() < 0)
            {
            // change Y velocity so ball is moving down
            iMySprite->SetYVelocity(-(iMySprite->GetYVelocity()));
            }
        else
            {
            return EKeyWasNotConsumed;
            }
        }
    else
        {
        return EKeyWasNotConsumed;
        }
    return EKeyWasConsumed;
    }


void CGraphicsLabAppView::StopAnimation() const
    {
    //Stop the timer if it is active
    if (iPeriodicTimer->IsActive())
        {
        iPeriodicTimer->Cancel();
        }
    }


void CGraphicsLabAppView::StartAnimation() 
    {
    StartTimer();
    }

void CGraphicsLabAppView::ResetCounter() const
    {
    // reset the counter to 0
    iMySprite->SetBounceCount(0);
    }

void CGraphicsLabAppView::StartTimer() 
    {
    //If the timer is not already running, start it
    if (!iPeriodicTimer->IsActive())
        {
        iPeriodicTimer->Start(1, KTimerIntervalMicroSeconds, TCallBack(CGraphicsLabAppView::Period,this));
        }

    }

void CGraphicsLabAppView::DoPeriodTask()
    {
    // Move the player's ball sprite
    iMySprite->Move(iBallImage->SizeInPixels(),Rect());
    // and the other balls
    for (TInt count = 0; count < iOtherSprites->Count(); count++)
        {
        iOtherSprites->At(count)->Move(iOtherBallImage->SizeInPixels(),Rect());
        }

    // Update the screen
    CWindowGc& gc = SystemGc();
    gc.Activate(*DrawableWindow());
    UpdateDisplay();
    gc.Deactivate();
    }


// This function is called by the periodic timer
TInt CGraphicsLabAppView::Period(TAny * aPtr)
    {
    ((CGraphicsLabAppView*)aPtr)->DoPeriodTask();
    //returning CGraphicsLabAppView value of TRUE indicates the callback should be done again
    return TRUE;
    }




// End of File