Win32 + Direct2D

Fareed Rizkalla

I've never used GDI in any of my projects. But had some programming introduction to it. Since I've been using Windows 7, I'm trying to build a new project with Direct2D. It compiles and runs, but it doesn't display anything! Does anyone have any experience, what could be the reason?

#include
#include

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hCurrInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
WNDCLASS SetFileTime = {};
SetFileTime.hInstance = hCurrInstance;
SetFileTime.lpfnWndProc = WndProc;
SetFileTime.lpszClassName = L"D2D";

RegisterClass(&SetFileTime);

CreateWindow(
	L"D2D",
	L"Direct2D",
	WS\_OVERLAPPEDWINDOW|WS\_VISIBLE,
	100, 100, 800, 600,
	NULL,
	NULL,
	hCurrInstance,
	NULL);

MSG WindowMessages = { };
while (GetMessage(&WindowMessages, NULL, 0, 0))
{
    TranslateMessage(&WindowMessages);
    DispatchMessage(&WindowMessages);
}

}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch (msg)
{
case WM_CREATE:
{
ID2D1Factory* pD2DFactory = NULL;
D2D1CreateFactory(D2D1_FACTORY_TYPE_MULTI_THREADED, &pD2DFactory);

		RECT rc;
		GetClientRect(hwnd, &rc);

		ID2D1HwndRenderTarget\* pRT = NULL;
		pD2DFactory->CreateHwndRenderTarget( D2D1::RenderTargetProperties(), 
			D2D1::HwndRenderTargetProperties(hwnd, D2D1::SizeU( rc.right - rc.left, rc.bottom - rc.top)),
			&pRT);



		ID2D1SolidColorBrush\* m\_pLightSlateGrayBrush = NULL;
		pRT->CreateSolidColorBrush( D2D1::ColorF(D2D1::ColorF::LightSlateGray), &m\_pLightSlateGrayBrush);
		

		D2D\_RECT\_F OriginalRect;
		OriginalRect.left = 10.f;
		OriginalRect.top = 10.f;
		OriginalRect.bottom = 100.f;
		OriginalRect.right = 100.f;

		D2D1\_ROUNDED\_RECT RoundedRect;
		RoundedRect.rect = OriginalRect;
		RoundedRect.radiusX = 1.0f;
		RoundedRect.radiusY = 1.0f;

		ID2D1RoundedRectangleGeometry\* Card = NULL;
		pD2DFactory->CreateRoundedRectangleGeometry(RoundedRect, &Card);

		pRT->BeginDraw();
		pRT->FillRoundedRectangle(&RoundedRect, m\_pLightSlateGrayBrush);
		pRT->DrawRoundedRectangle(&RoundedRect, m\_pLightSlateGrayBrush);
		pRT->EndDraw();

		return 0;
	}
	case WM\_CLOSE:
	{
		DestroyWindow(hwnd);
		return 0;
	}
	case WM\_DESTROY:
	{
		PostQuitMessage(0);
		return 0;
	}
	default:
		return DefWindowProc(hwnd, msg, wParam, lParam);
}

}

Cedric Moonen

You don't handle the WM_PAINT message, in which all the drawing code should be put. You have put everything in WM_CREATE, which is called when the window is being created. I suggest you read the following article[^] to get a basic understanding of how it works.

Cédric Moonen Software developer
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