Rotate Emf with Gradient

[khaldoun KASSEM]

Hi

I want to rotate Emf Images, I am using GDI, winXP.

I can get it to work with most emf images, but recently I detect that when the emf image contain a gradient, the image is rotated but the gradient disappear...
After testing I find that it depends on the size of the output...

I Attached the project which demostrate the problem with corresponding images.

my sample is based on a PrintPic by Feng Yuan

any Idea? what am i doing wrong?

void SavePictureRotate(const TCHAR * pFileName,const TCHAR * pDstFileName, int nMmWidth, int nMmHeight)
{
	RECT rcRect;
	rcRect.left = 0;
	rcRect.top = 0;
	rcRect.right = nMmWidth*100; 
	rcRect.bottom = nMmHeight*100; 

	::DeleteFile(pDstFileName);

	HDC hEmfDC = CreateEnhMetaFile(
		NULL,pDstFileName,&rcRect,NULL);


	CDC *pDc = CDC::FromHandle(hEmfDC);
	int nGraphicMode = pDc->SetGraphicsMode(GM_ADVANCED);
	int nMapMode = pDc->SetMapMode( MM_ANISOTROPIC);

	float fHorzResolution = (float)pDc->GetDeviceCaps(LOGPIXELSX);
	float fVertResolution = (float)pDc->GetDeviceCaps(LOGPIXELSY);

	float fMmToPxlHorz = fHorzResolution/25.4f;
	float fMmToPxlVert = fVertResolution/25.4f;

	float fPxlWidth = (nMmWidth/25.4f*fHorzResolution) / 2.0f;
	float fPxlHeight = (nMmHeight/25.4f*fVertResolution) / 2.0f;


	XFORM xForm2; 
	xForm2.eM11 = (FLOAT) 1; 
	xForm2.eM12 = (FLOAT) 0; 
	xForm2.eM21 = (FLOAT) 0; 
	xForm2.eM22 = (FLOAT) 1; 
	xForm2.eDx  = (FLOAT) fPxlWidth / 2.0f; 
	xForm2.eDy  = (FLOAT) fPxlHeight / 2.0f;

	BOOL bRet = pDc->ModifyWorldTransform(&xForm2,MWT_LEFTMULTIPLY); 
	DWORD dwError = GetLastError();
	double dAlpha = (360-10) * PI / 180.0;
	XFORM xForm3; 
	xForm3.eM11 = (FLOAT) cos(dAlpha); 
	xForm3.eM12 = (FLOAT) sin(dAlpha); 
	xForm3.eM21 = (FLOAT) -sin(dAlpha); 
	xForm3.eM22 = (FLOAT) cos(dAlpha); 
	xForm3.eDx  = (FLOAT) 0.0; 
	xForm3.eDy  = (FLOAT) 0.0; 

	bRet =  pDc->ModifyWorldTransform(&xForm3,MWT_LEFTMULTIPLY); 

	HENHMETAFILE hemf = GetEnhMetaFile(pFileName); 

	RECT rcDest;
	rcDest.left = 0;
	rcDest.top = 0;
	rcDest.right = (int)fPxlWidth; //1000mm
	rcDest.bottom = (int)fPxlHeight; //1600mm

	pDc->PlayMetaFile(hemf,&rcDest);

	DeleteEnhMetaFile(hemf);

	HENHMETAFILE hEMF = CloseEnhMetaFile(hEmfDC);
	DeleteEnhMetaFile(hEMF);
}
int APIENTRY WinMain(HINSTANCE hInstance,
					 HINSTANCE hPrevInstance,
					 LPSTR     lpCmdLine,
					 int       nCmdShow)
{
	SavePictureRotate("./EmfImages/withgradient.emf","./EmfImages/withgradientrotate_1000x1600.emf",1000,1600);
	SavePictureRotate("./EmfImages/withoutgradient.emf","./EmfImages/withoutgradientrotate_1000x1600.emf",1000,1600);
	
	SavePictureRotate("./EmfImages/withgradient.emf","./EmfImages/withgradientrotate_100x160.emf",100,160);
	SavePictureRotate("./EmfImages/withoutgradient.emf","./EmfImages/withoutgradientrotate_100x160.emf",100,160);

	return 0;
}

Thank you
Khaldoun