examples/Graphics/coverflow/src/openvgengine.cpp

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// openvgengine.cpp
//
// Copyright (c) 2005-2008 Symbian Ltd.  All rights reserved.
//
#include <eikenv.h>
#include "openvgengine.h"
#include "eglrendering.h"
#include <e32math.h>

GLDEF_D VGUErrorCode vguComputeWarpQuadToQuadProxy(VGfloat aDx0, VGfloat aDy0,
                                                   VGfloat aDx1, VGfloat aDy1,
                                                   VGfloat aDx2, VGfloat aDy2,
                                                   VGfloat aDx3, VGfloat aDy3,
                                                   VGfloat aSx0, VGfloat aSy0,
                                                   VGfloat aSx1, VGfloat aSy1,
                                                   VGfloat aSx2, VGfloat aSy2,
                                                   VGfloat aSx3, VGfloat aSy3,
                                                   VGfloat* aMatrix)
        {
        // sets the entries of aMatrix to the projective transformation
        // This maps:
        // (aSx0,aSy0) to (aDx0,aDy0)
        // (aSx1,aSy1) to (aDx1,aDy1)
        // (aSx2,aSy2) to (aDx2,aDy2)
        // (aSx3,aSy3) to (aDx3,aDy3)
        vguComputeWarpQuadToQuad(
                                                   aSx0, aSy0,
                                                   aSx1, aSy1,
                                                   aSx2, aSy2,
                                                   aSx3, aSy3,
                                                   aDx0, aDy0,
                                                   aDx1, aDy1,
                                                   aDx2, aDy2,
                                                   aDx3, aDy3,
                                                   aMatrix);
        return VGU_NO_ERROR;
        }

COpenVGEngine* COpenVGEngine::NewL(TSize aWindowSize,EGLDisplay& aDisplay, EGLSurface& aSurface, EGLContext& aContext)
        {
        COpenVGEngine* self = new(ELeave) COpenVGEngine(aWindowSize,aDisplay,aSurface,aContext);
        return self;
        }

COpenVGEngine::~COpenVGEngine()
        {
        Deactivate();
        }

TInt COpenVGEngine::GetSpeed()
        {
        return static_cast<TInt>(iSpeed*100000);
        }

TBool COpenVGEngine::IsPending()
        {
        return iHasPendingDraw;
        }

void COpenVGEngine::ActivateL()
        {
        // Setup initial OpenVG context state.
        VGfloat clearColour[] = { 0.1f, 0.1f, 0.2f, 1.0f };
        // Set the value of  VG_CLEAR_COLOR to clearcolour.
        vgSetfv(VG_CLEAR_COLOR, 4, clearColour);
        // Set the image quality mode setting to VG_IMAGE_QUALITY_NONANTIALIASED.
        vgSeti(VG_IMAGE_QUALITY, VG_IMAGE_QUALITY_NONANTIALIASED);
        // Set the rendering quality mode setting to VG_RENDERING_QUALITY_NONANTIALIASED.
        vgSeti(VG_RENDERING_QUALITY, VG_RENDERING_QUALITY_NONANTIALIASED);
        vgSeti(VG_MATRIX_MODE, VG_MATRIX_IMAGE_USER_TO_SURFACE);

        //Load and create the VGImage.
#ifdef __WINS__
        _LIT(KCoverBitmaps,"z:\\resource\\apps\\covers.mbm");
#else
        _LIT(KCoverBitmaps,"e:\\resource\\apps\\covers.mbm");
#endif
        // Create a bitmap image.
        // This is used to load all bitmap images to display them on the screen.
        CFbsBitmap* bitmap = new(ELeave) CFbsBitmap();
        CleanupStack::PushL(bitmap);
        TInt i = 0;
        // Load cover images.
        while(bitmap->Load(KCoverBitmaps,i++) == KErrNone)
                {
                TSize coverSize = bitmap->SizeInPixels();

                // Set the pixel format and colour to  VG_sRGB_565.s
                VGImageFormat dataFormat = VG_sRGB_565;
                VGint width = coverSize.iWidth;
                VGint height = coverSize.iHeight;
                // Get the amount of bytes per scanline.
                VGint dataStride = bitmap->ScanLineLength(coverSize.iWidth,bitmap->DisplayMode());

                // Create the VGImage.
                VGImage image = vgCreateImage(dataFormat, width, height,VG_IMAGE_QUALITY_NONANTIALIASED);
                CEGLRendering::VGCheckError();

                // Load Symbian bitmap into VGImage.
                vgImageSubData (image, bitmap->DataAddress(), dataStride, dataFormat, 0, 0, width, height );
                CEGLRendering::VGCheckError();

                // Add the image to the iImages array.
                iImages.AppendL(image);
                iHasPendingDraw = ETrue;
                }

        CleanupStack::Pop(bitmap);
        delete bitmap;

        // Check if no image is loaded.
        if(iImages.Count() == 0)
                {
                User::Leave(KErrNotFound);
                }

        iImage = iImages[0];

        // Create a new paint object.
        iShadowPaint = vgCreatePaint();
        if (iShadowPaint != VG_INVALID_HANDLE)
                {
                VGfloat paintColour[4] = { 0.4f, 0.4f, 0.6f, 1.0f };
                // Passing paintColour to the paint object.
                vgSetParameterfv(iShadowPaint, VG_PAINT_COLOR, 4, paintColour);
                CEGLRendering::VGCheckError();
                }
        }

void COpenVGEngine::Deactivate()
        {
        TInt coverIndex=iImages.Count()-1;
        for (;coverIndex>=0;coverIndex--)
                {
                // De allocate the resources of all images in the iImages array.
                vgDestroyImage(iImages[coverIndex]);
                }

        // Destroy the paint object.
        vgDestroyPaint(iShadowPaint);
        eglWaitClient();

        // Reset the RArray.
        iImages.Reset();
        iHasPendingDraw = EFalse;
        }

void COpenVGEngine::Step()
        {
#ifdef PORTRAIT_MODE
        vgClear(0, 0, iSurfaceSize.iHeight, iSurfaceSize.iWidth);
#else
        vgClear(0, 0, iSurfaceSize.iWidth, iSurfaceSize.iHeight);
#endif
        // Calculate the speed of movement of the cover
        // depending on its current location.
        if (Abs(iCoverLocation[iWantedCover]) < 0.03)
                {
                iSpeed = 0.0f;
                iHasPendingDraw = EFalse;
                }
        else if (Abs(iCoverLocation[iWantedCover]) < 0.5)
                {
                iSpeed*=0.7;
                }
        else
                {
                iSpeed = 0.05*(2+ Abs(iCoverLocation[iWantedCover]) + (Abs(iCoverLocation[iWantedCover])+1) * (Abs(iCoverLocation[iWantedCover])+1) / 2);
                }
        // For each Cover, update its location in the correct direction.
        // Check if the wanted cover is already at the CenterStage point.
        VGfloat moveEachCover = iSpeed;
        if (iCoverLocation[iWantedCover] > 0.0)
                {
                moveEachCover *= -1;
                }

        TInt coverIndex;
        // Update the location of each cover.
        for (coverIndex = 0; coverIndex < KMaxCoversExample3; ++coverIndex)
                {
                iCoverLocation[coverIndex] += moveEachCover;
                }

        TInt coverClippingCount = 10;
        TInt middleCoverPos=0;
        VGfloat threshold = 0.50f;

        while(Abs(iCoverLocation[middleCoverPos])>threshold)
                {
                ++middleCoverPos;
                }


        //left.
        TInt cutOff = middleCoverPos-coverClippingCount;
        if (cutOff<0)
                {
                cutOff=0;
                }
        for (TInt i=cutOff; i<middleCoverPos;i++)
                {
                DrawCover(i);
                }

        //right.
        cutOff = coverClippingCount + middleCoverPos;
        if (cutOff>=KMaxCoversExample3)
                {
                cutOff=KMaxCoversExample3-1;
                }

        for (TInt j = cutOff; j>=middleCoverPos ; --j)
                {
                DrawCover(j);
                }

#ifdef ENABLE_LOOP
        static TInt dir = 1;
        if (iWantedCover == (KMaxCoversExample3-1))
                {
                dir = -1;
                }
        else if (iWantedCover == 0)
                {
                dir = 1;
                }

        iWantedCover += dir;
        iHasPendingDraw = ETrue;
#endif
        }

void COpenVGEngine::DrawCover(TInt aCoverIndex)
        {
        VGImage image = iImages[aCoverIndex%iImages.Count()];
        // Starting at the outside, render each visible (+/-  KMaxDisplayCoversExample3/2) Cover.
        // Calculate its path.

        // Set the current matrix to the identity matrix.
        vgLoadIdentity();

#ifdef PORTRAIT_MODE
        vgTranslate(iSurfaceSize.iHeight, 0);
        vgRotate(90);
#endif

        VGfloat coverPosition = iCoverLocation[aCoverIndex];

        VGfloat tempMatrix[3][3];
        //flip coordinates.
        VGfloat flipmatrix[] =
                {
                1.0f, 0.0f, 0.0f,
                0.0f, -1.0f, 0.0f,
                0.0f, 0.0f, 1.0f
                };
        vgMultMatrix(flipmatrix);

        VGint imageWidth = vgGetParameteri (image, VG_IMAGE_WIDTH);
        VGint imageHeight = vgGetParameteri (image, VG_IMAGE_HEIGHT);

        VGint yTrans = -200;

        // Factors which must be multiplied with side of image which will be projected towards back.
        // Valid if projecting right image side to back.
        // Opposite is (1 - factor) for projecting left image side.

        VGfloat bottomProjectXFactor= (0.75f);
        VGfloat bottomProjectYFactor = (0.20f);

        VGfloat topProjectXFactor = (0.75f);
        VGfloat topProjectYFactor = (0.90f);

        VGfloat imageSpacingFactor = 0.16;

        VGfloat translationOffset = 0.0;

        VGfloat middleTranslationOffset = KImageSize /2;
        VGfloat coverProjectionLimit = 10;

        if (coverPosition>=1)
                {
                // If considering an image on the right side, this is offset from middle to place image on screen.
                translationOffset = middleTranslationOffset- KImageSize/2 + KImageSize*imageSpacingFactor * (coverPosition -1);

                // Left side of image goes back.
                vguComputeWarpQuadToQuadProxy(  0.0f, 0.0f,
                                   imageWidth, 0.0f,
                                   0.0f, imageHeight,
                                   imageWidth, imageHeight,

                                   KImageSize * (1 - bottomProjectXFactor*(1-Abs(coverPosition)/coverProjectionLimit)),KImageSize * bottomProjectYFactor,// left vertex.
                                   KImageSize, 0.0f,
                                   KImageSize * (1 - topProjectXFactor*(1-Abs(coverPosition)/coverProjectionLimit)), KImageSize * topProjectYFactor,// left vertex.
                                   KImageSize, KImageSize,

                                   &tempMatrix[0][0]);
                }
        else if (coverPosition<-1)
                {
                // Must move an extra image width from centre , as coordinates from bottom left corner of image.
                translationOffset = - (middleTranslationOffset + (KImageSize * imageSpacingFactor) * ( -coverPosition - 1) + KImageSize/2) ;

                vguComputeWarpQuadToQuadProxy(  0.0f, 0.0f,
                                   imageWidth, 0.0f,
                                   0.0f, imageHeight,
                                   imageWidth, imageHeight,

                                   0.0f, 0.0f,
                                   (bottomProjectXFactor*(1-Abs(coverPosition)/coverProjectionLimit))* KImageSize, bottomProjectYFactor * KImageSize, //Right Vertex.
                                   0.0f, (KImageSize),
                                   (topProjectXFactor*(1-Abs(coverPosition)/coverProjectionLimit)) * KImageSize, topProjectYFactor * KImageSize, //Right Vertex

                                   &tempMatrix[0][0]);
                }
        else if((coverPosition > -1) && (coverPosition <= 0))// -0.07))
                {
                translationOffset = -middleTranslationOffset * Abs(coverPosition) - KImageSize/2 ;

                vguComputeWarpQuadToQuadProxy(  0.0f, 0.0f,
                                                           imageWidth, 0.0f,
                                                           0.0f, imageHeight,
                                                           imageWidth, imageHeight,

                                                           0.0f, 0.0f,
                                                           KImageSize * (1 - (1-bottomProjectXFactor) * Abs(coverPosition)), KImageSize * bottomProjectYFactor * Abs(coverPosition),
                                                           0.0f, KImageSize,
                                                           (KImageSize * (1 - ( 1 - topProjectXFactor) * Abs(coverPosition))) , KImageSize * (1 - (1 - topProjectYFactor) * Abs(coverPosition)),

                                                           &tempMatrix[0][0]);

                }

        else if ((coverPosition >=0) && (coverPosition <= 1))
                {

                translationOffset = middleTranslationOffset * Abs(coverPosition) - KImageSize/2 ;

                vguComputeWarpQuadToQuadProxy( 0.0f, 0.0f,
                                                           imageWidth, 0.0f,
                                                           0.0f, imageHeight,
                                                           imageWidth, imageHeight,

                                                           KImageSize * (1-bottomProjectXFactor)* (coverPosition), KImageSize * (bottomProjectYFactor) * (coverPosition),
                                                           KImageSize, 0,
                                                           KImageSize * ( 1 - topProjectXFactor) * (coverPosition) , KImageSize * (1 - (1 - topProjectYFactor) * Abs(coverPosition)),
                                                           KImageSize, KImageSize,

                                                           &tempMatrix[0][0]);
                }


        iSpeedOffset = 140*(iSpeed)*(iSpeed);

                        if (iCoverLocation[iWantedCover]<0)
                                {
                                iSpeedOffset *=-1;
                                }

        // Apply transformations to the current matrix.
        vgTranslate(iSurfaceSize.iWidth/2 + translationOffset + iSpeedOffset,yTrans);

        vgMultMatrix(&tempMatrix[0][0]);
        if (Abs(coverPosition)<=1)
                {
                VGfloat scale = GetMiddleCoverScalingFactor(coverPosition);
                vgScale(scale,scale);

                vgTranslate(-(scale-1)/2 * KImageSize,-(scale-1)/2 * KImageSize);
                }

        // Draw the image on the surface.
        vgDrawImage(image);
        CEGLRendering::VGCheckError();

        // Check if mirror images of covers have to be displayed.
        if(iShowMirror)
                {
                // Scale the current matrix to create inverted images.
                vgScale(1,-1);
                vgSeti(VG_IMAGE_MODE, VG_DRAW_IMAGE_MULTIPLY);
                vgTranslate(0,-4*KImageSize+226);

                // Draw the image on the surface.
                vgSetPaint(iShadowPaint, VG_FILL_PATH);
                vgDrawImage(image);
                CEGLRendering::VGCheckError();

                vgSeti(VG_IMAGE_MODE,VG_DRAW_IMAGE_NORMAL);
                }
        }

TKeyResponse COpenVGEngine::HandleKeyEventL(const TKeyEvent& aKeyEvent)
        {
        TKeyResponse response = EKeyWasConsumed;
        switch (aKeyEvent.iCode)
                {
        case EKeyRightArrow:
        // Move to the next cover if right arrow key is pressed.
                NextCover();
                break;

        case EKeyLeftArrow:
        // Move to the previous cover if left arrow key is pressed.
        PreviousCover();
                break;

        case EKeyBackspace:
        // Toggle the cover reflection flag.
                ToggleCoverReflection();
                break;
        default:
                response = EKeyWasNotConsumed;
                break;
                };
        return response;
        }

COpenVGEngine::COpenVGEngine(TSize aWindowSize,EGLDisplay& aDisplay, EGLSurface& aSurface, EGLContext& aContext) :
        iDisplay(aDisplay),iSurface(aSurface),iContext(aContext),iWantedCover(20),iHasPendingDraw(EFalse),
        iShowMirror(ETrue)
        {
#ifdef PORTRAIT_MODE
        iSurfaceSize.iWidth = aWindowSize.iHeight;
        iSurfaceSize.iHeight = aWindowSize.iWidth;
#else
        iSurfaceSize = aWindowSize;
#endif
        // Initiate the location of each cover & make the wanted one the cover at the opposite end
        for(TInt i=0; i<KMaxCoversExample3; ++i)
                {
                iCoverLocation[i] = i;
                }
        }

void COpenVGEngine::NextCover()
        {
        if (iWantedCover < (KMaxCoversExample3-1))
                {
                ++iWantedCover;
                }
        iHasPendingDraw = ETrue;
        }

void COpenVGEngine::PreviousCover()
        {

        if (iWantedCover>0)
                {
                --iWantedCover;
                }
        iHasPendingDraw = ETrue;
        }

void COpenVGEngine::ToggleCoverReflection()
        {
        iShowMirror = !iShowMirror;
        }

VGfloat COpenVGEngine::GetMiddleCoverScalingFactor(VGfloat aCoverPosition)
        {
        if(Abs(aCoverPosition)>1)
                {
                return 0.0f;
                }

        return (-0.125 * Abs(aCoverPosition) + 1.125);
        }

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