Direct2D 极速教程(3) —— 画动态淳平

创建新项目：003-DrawDynamicJunpei

新建项目 “003-DrawDynamicJunpei”，将上面的 " 淳平接受采访.gif " 添加进上面文件夹即可。

画动态淳平

有

#include<Windows.h>
#include<wincodec.h>
#include<wrl.h>
#include<d2d1.h>
#include<vector>

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

using namespace Microsoft::WRL;

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

ComPtr<ID2D1Factory> m_D2DFactory;				// D2D 工厂
ComPtr<ID2D1HwndRenderTarget> m_RenderTarget;	// 窗口渲染目标
ComPtr<ID2D1SolidColorBrush> m_Brush;			// 纯色画刷
ComPtr<ID2D1Bitmap> m_Bitmap;					// D2D 位图

ComPtr<IWICImagingFactory> m_WICFactory;		// WIC 工厂
ComPtr<IWICBitmapDecoder> m_BitmapDecoder;		// 位图解码器
ComPtr<IWICBitmapFrameDecode> m_DecodeFrame;	// 位图解码帧
ComPtr<IWICFormatConverter> m_Converter;		// 位图转换器

UINT FrameCount = 0;	// 图片帧数
UINT NowPlayFrame = 0;	// 当前播放帧

const UINT width = 1080;
const UINT height = 720;

D2D1_RECT_F rect = {};

std::vector<ComPtr<ID2D1Bitmap>> bitmaps;	// 图片集合

int WINAPI WinMain(HINSTANCE hins, HINSTANCE hPrev, LPSTR lpstr, int cmdShow)
{
	WNDCLASS wc = {};
	wc.hInstance = hins;
	wc.lpszClassName = L"D2D";
	wc.lpfnWndProc = callBackFunc;
	wc.hbrBackground = (HBRUSH)GetStockObject(NULL_BRUSH);

	RegisterClass(&wc);

	HWND hwnd = CreateWindow(wc.lpszClassName, L"淳平", WS_OVERLAPPEDWINDOW | WS_VISIBLE,
		CW_USEDEFAULT, CW_USEDEFAULT, width, height, NULL, NULL, hins, NULL);

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


LRESULT CALLBACK callBackFunc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	switch (msg)
	{
	case WM_CREATE: {	// 在这里创建 D2D 设备

		CoInitialize(nullptr);

		// 创建 D2D 工厂
		D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED, m_D2DFactory.GetAddressOf());

		D2D1_RENDER_TARGET_PROPERTIES properties = D2D1::RenderTargetProperties();

		RECT rc = {};
		GetClientRect(hwnd, &rc);

		rect = D2D1::Rect(rc.left, rc.top, rc.right, rc.bottom);
		
		D2D1_HWND_RENDER_TARGET_PROPERTIES Hwndproperties = {};
		Hwndproperties.hwnd = hwnd;											// 窗口句柄
		Hwndproperties.pixelSize.width = rc.right - rc.left;				// 渲染目标宽度
		Hwndproperties.pixelSize.height = rc.bottom - rc.top;				// 渲染目标高度
		Hwndproperties.presentOptions = D2D1_PRESENT_OPTIONS_NONE;			// 自动选择呈现模式

		// 创建窗口渲染目标
		m_D2DFactory->CreateHwndRenderTarget(properties, Hwndproperties, &m_RenderTarget);

		

		// 创建纯色画刷
		m_RenderTarget->CreateSolidColorBrush(D2D1::ColorF(D2D1::ColorF::Blue), &m_Brush);


		// 创建 WIC 工厂
		CoCreateInstance(CLSID_WICImagingFactory, nullptr, CLSCTX_INPROC_SERVER, IID_PPV_ARGS(&m_WICFactory));

		// 读取图片数据并创建解码器
		m_WICFactory->CreateDecoderFromFilename(L"淳平接受采访.gif", nullptr, GENERIC_READ,
			WICDecodeMetadataCacheOnDemand, &m_BitmapDecoder);

		// 读取图片数量
		m_BitmapDecoder->GetFrameCount(&FrameCount);

		// 一页一页，这样就和普通的图片没区别了
		for (UINT i = 0; i < FrameCount; i++)
		{
			// 获取每一帧图片
			m_BitmapDecoder->GetFrame(i, &m_DecodeFrame);

			// 创建转换器
			m_WICFactory->CreateFormatConverter(&m_Converter);

			// 将图片进行转换，注意 D2D 位图格式都是 GUID_WICPixelFormat32bppPBGRA
			m_Converter->Initialize(m_DecodeFrame.Get(), GUID_WICPixelFormat32bppPBGRA, WICBitmapDitherTypeNone,
				nullptr, 0, WICBitmapPaletteTypeCustom);

			// 将 WIC 位图转换成 D2D 位图
			m_RenderTarget->CreateBitmapFromWicBitmap(m_Converter.Get(), &m_Bitmap);

			// 把转换后的每一帧位图都加进 vector 里
			bitmaps.push_back(m_Bitmap);
		}

	} break;

	case WM_PAINT: {	// 在这里进行绘制操作

		m_RenderTarget->BeginDraw();

		// 一个一个一个一个一个读啊，啊啊啊啊啊啊啊啊啊啊啊啊啊
		m_RenderTarget->DrawBitmap(bitmaps[NowPlayFrame].Get(), rect);

		m_RenderTarget->EndDraw();

		Sleep(60);

		NowPlayFrame++;
		NowPlayFrame %= FrameCount;

	} break;

	case WM_DESTROY: {
		PostQuitMessage(0);
	} break;

	default: return DefWindowProc(hwnd, msg, wParam, lParam);
	}

	return 0;
}