Original : https://github.com/sakura-editor/sandbox/commit/70de4e37a0a47b36d30cfca9473a8e77bda5cefb

patblt_speed_test.cpp

#include <Windows.h>
#include <stdio.h>

struct CStopWatch final
{
	const char* title;
	LARGE_INTEGER frequency;
	LARGE_INTEGER startTime;

	CStopWatch( const char* pszTitle )
		: title( pszTitle )
	{
		::QueryPerformanceFrequency( &frequency );
		::QueryPerformanceCounter( &startTime );
	}
	~CStopWatch( void )
	{
		LARGE_INTEGER endTime;
		::QueryPerformanceCounter( &endTime );
		double elapsedSec = (endTime.QuadPart - startTime.QuadPart) / (double)frequency.QuadPart;
		char buf[128];
		::sprintf_s( buf, "%s elapsed=%f sec\n", title, elapsedSec );
		::OutputDebugStringA( buf );
	}
};

constexpr size_t MAX_COUNT = 60;

void case1(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		HBRUSH brush = ::CreateSolidBrush( RGB( 0xff, 0xff, 0 ) );
		::FillRect( hDC, &rc, brush );
		::DeleteObject( brush );
	}
}

void case2(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		COLORREF bkColor = RGB( 0xff, 0xff, 0 );
		COLORREF bkColorOld = ::SetBkColor( hDC, bkColor );
		::ExtTextOutW( hDC, rc.left, rc.top, ETO_OPAQUE, &rc, L"", 0, NULL );
		::SetBkColor( hDC, bkColorOld );
	}
}

void case3(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		HBRUSH brush = ::CreateSolidBrush( RGB( 0xff, 0xff, 0 ) );
		HGDIOBJ brushOld = ::SelectObject( hDC, brush );
		::PatBlt( hDC, rc.left, rc.top, rc.right, rc.bottom, PATCOPY );
		::SelectObject( hDC, brushOld );
		::DeleteObject( brush );
	}
}

void case4(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	HBRUSH brush = ::CreateSolidBrush( RGB( 0xff, 0xff, 0 ) );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		::FillRect( hDC, &rc, brush );
	}
	::DeleteObject( brush );
}

void case5(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	COLORREF bkColor = RGB( 0xff, 0xff, 0 );
	COLORREF bkColorOld = ::SetBkColor( hDC, bkColor );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		::ExtTextOutW( hDC, rc.left, rc.top, ETO_OPAQUE, &rc, L"", 0, NULL );
	}
	::SetBkColor( hDC, bkColorOld );
}

void case6(HDC hDC, const RECT& rc)
{
	CStopWatch sw( __FUNCTION__ );
	HBRUSH brush = ::CreateSolidBrush( RGB( 0xff, 0xff, 0 ) );
	for ( size_t n = 0; n < MAX_COUNT; n++ ) {
		HGDIOBJ brushOld = ::SelectObject( hDC, brush );
		::PatBlt( hDC, rc.left, rc.top, rc.right, rc.bottom, PATCOPY );
		::SelectObject( hDC, brushOld );
	}
	::DeleteObject( brush );
}


//! Main関数
int WINAPI wWinMain(
	HINSTANCE	hInstance,		//!< handle to current instance
	HINSTANCE	hPrevInstance,	//!< handle to previous instance
	LPWSTR		lpCmdLine,		//!< pointer to command line
	int			nCmdShow		//!< show state of window
)
{
	HWND hWnd = ::GetDesktopWindow();
	RECT rc;
	::GetWindowRect( hWnd, &rc );
	HDC hDC = ::GetDC( hWnd );
	HDC hMemoryDC = ::CreateCompatibleDC( NULL );
	int cx = rc.right - rc.left;
	int cy = rc.bottom - rc.top;
	HBITMAP hBitmap = ::CreateCompatibleBitmap( hMemoryDC, cx, cy );
	HGDIOBJ hPrevObj = ::SelectObject( hMemoryDC, hBitmap );

	auto runTestCases = [](HDC hDC, const RECT& rc) {
		case1( hDC, rc );
		case2( hDC, rc );
		case3( hDC, rc );
		case4( hDC, rc );
		case5( hDC, rc );
		case6( hDC, rc );
	};

	::OutputDebugStringW( L"Desktop Window DC\n" );
	runTestCases(hDC, rc);

	::OutputDebugStringW( L"Memory DC\n" );
	runTestCases( hMemoryDC, rc );

	::SelectObject( hMemoryDC, hPrevObj );
	::DeleteObject( hBitmap );
	::DeleteDC( hMemoryDC );
	::ReleaseDC( hWnd, hDC );
	return 0;
}