Direct2D 第1篇 最简单的D2D程序

原文:Direct2D 第1篇 最简单的D2D程序

编译之前，得先安装DirectX SDK

#include <windows.h>

#include <d2d1.h>

#include <d2d1helper.h>

#include <dwrite.h>

#pragma comment(lib, "dwrite.lib")

#pragma comment(lib, "d2d1.lib")

static HINSTANCE g_hinst;

static HWND g_hwnd;

static bool g_flag_app_exit;

static ID2D1Factory * g_factory;

static ID2D1HwndRenderTarget * g_render_target;

void OnSize(LPARAM lparam)

{

    if(g_render_target)

        g_render_target->Resize(D2D1::SizeU(LOWORD(lparam),HIWORD(lparam)));

}

bool AppInit()

{

    D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED, &g_factory);

    RECT rc;

    GetClientRect(g_hwnd, &rc);

    g_factory->CreateHwndRenderTarget(

        D2D1::RenderTargetProperties(),

        D2D1::HwndRenderTargetProperties(g_hwnd, D2D1::SizeU(rc.right - rc.left, rc.bottom - rc.top)    ),

        &g_render_target);

    return true;

}

void OnPaint()

{

    if(!g_render_target)

        return;

    g_render_target->BeginDraw();

    g_render_target->Clear(D2D1::ColorF(0.63, 0.84, 0.00));

    g_render_target->EndDraw();

}

void AppExit()

{

    g_render_target->Release();

    g_factory->Release();

}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)

{

    switch(msg)

    {

    case WM_PAINT:

        OnPaint();

        break;

    case WM_SIZE:

        OnSize(lparam);

        break;

	case WM_DESTROY:

        g_flag_app_exit = true;

        break;

    default:

        return DefWindowProc(hwnd, msg, wparam, lparam);

    }

    return 0;

}

int WINAPI WinMain(HINSTANCE hinst, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)

{

    WNDCLASSEX wc;

    MSG msg;

    memset(&wc,0,sizeof(wc));

    wc.cbSize = sizeof(WNDCLASSEX);

    wc.lpfnWndProc = WndProc;

    wc.hInstance = hinst;

    wc.hCursor = LoadCursor(NULL, IDC_ARROW);

    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);

    wc.lpszClassName = "WindowClass";

    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);

    wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);

    if(!RegisterClassEx(&wc))

    {

        MessageBox(NULL, "Window Registration Failed!","Error!",MB_ICONEXCLAMATION|MB_OK);

        return 0;

    }

    g_hinst = hinst;

    g_hwnd = CreateWindowEx(WS_EX_CLIENTEDGE,"WindowClass","Direct2D Demo",WS_VISIBLE|WS_OVERLAPPEDWINDOW,

        CW_USEDEFAULT,

        CW_USEDEFAULT,

        640,

        480,

        NULL, NULL, hinst, NULL);

    if(g_hwnd == NULL)

    {

        MessageBox(NULL, "Window Creation Failed!","Error!",MB_ICONEXCLAMATION|MB_OK);

        return 0;

    }

    if(!AppInit())

    {

        MessageBox(NULL, "Application Initialisation Failed !","Error",MB_ICONEXCLAMATION|MB_OK);

        return 0;

    }

    while(!g_flag_app_exit)

    {

		if(PeekMessage(&msg, g_hwnd, 0, 0, PM_REMOVE))

		{

			TranslateMessage(&msg);

			DispatchMessage(&msg);

		}

    }

	AppExit();

    return msg.wParam;

}