为方便，将D2D的一个基本类DesktopWindow写成如下所示：

#include "Precompiled.h"#include 
      
       #include 
       
        #pragma comment(lib, "d2d1")using namespace D2D1;using namespace Microsoft::WRL;template
        
         struct DesktopWindow    : CWindowImpl
         
          >{    ComPtr
          
            m_factory;    ComPtr
           
             m_target; DECLARE_WND_CLASS_EX(L"My D2D1 Window", CS_HREDRAW | CS_VREDRAW, -1); BEGIN_MSG_MAP(DesktopWindow) MESSAGE_HANDLER(WM_PAINT, PaintHandler) MESSAGE_HANDLER(WM_DESTROY, DestroyHandler) MESSAGE_HANDLER(WM_SIZE, SizeHandler) MESSAGE_HANDLER(WM_DISPLAYCHANGE, DisplayChangeHandler) END_MSG_MAP() LRESULT DisplayChangeHandler(UINT, WPARAM, LPARAM, BOOL&) { Invalidate(); return 0; } LRESULT SizeHandler(UINT, WPARAM, LPARAM lparam, BOOL&) { if (m_target) { if (m_target->Resize(SizeU(LOWORD(lparam), HIWORD(lparam))) != S_OK) { m_target.Reset(); } } return 0; } LRESULT PaintHandler(UINT, WPARAM, LPARAM, BOOL&) { PAINTSTRUCT ps; VERIFY(BeginPaint(&ps)); Render(); EndPaint(&ps); return 0; } LRESULT DestroyHandler(UINT, WPARAM, LPARAM, BOOL&) { PostQuitMessage(0); return 0; } void Invalidate() { VERIFY(InvalidateRect(nullptr, false)) } void Render() { if (!m_target) { RECT rect; VERIFY(GetClientRect(&rect)); auto size = SizeU(rect.right, rect.bottom); m_factory->CreateHwndRenderTarget(RenderTargetProperties(), HwndRenderTargetProperties(m_hWnd, size), m_target.GetAddressOf()); static_cast
            
             (this)->CreateDeviceResources(); } if (!(m_target->CheckWindowState() & D2D1_WINDOW_STATE_OCCLUDED)) { m_target->BeginDraw(); static_cast
             
              (this)->Draw(); if (m_target->EndDraw() == D2DERR_RECREATE_TARGET) { m_target.Reset(); } } } int Run() { D2D1_FACTORY_OPTIONS fo = {};#ifdef DEBUG fo.debugLevel = D2D1_DEBUG_LEVEL_INFORMATION;#endif D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED, fo, m_factory.GetAddressOf()); CreateDeviceIndependentResources(); VERIFY(__super::Create(nullptr, 0, L"title")); MSG msg; BOOL result; while (result = GetMessage(&msg, 0, 0, 0)) { if (result != -1) { DispatchMessage(&msg); } } return msg.wParam; } virtual void CreateDeviceIndependentResources() {}};
             
            
           
          
         
        
       
      

所有的画笔(Brush)都有SetOpacity和SetTransform两个方法，所有的单色画笔(SolidColorBrush)都有SetColor方法，可以设置颜色。

画笔是可修改的（mutable），因此，可以只声明一个画笔，然后在使用的时候，不断地更换颜色。

最简单的单色画笔(SolidColorBrush)示例如下所示：

#include "Precompiled.h"#include "DesktopWindow.h"D2D1_COLOR_F const COLOR_BLUE    = { 0.26f, 0.56f, 0.87f, 1.0f };D2D1_COLOR_F const COLOR_YELLOW = { 0.99f, 0.85f, 0.0f,  1.0f };D2D1_COLOR_F const COLOR_BLACK  = { 0.0f,  0.0f,  0.0f,  1.0f };D2D1_COLOR_F const COLOR_WHITE  = { 1.0f,  1.0f,  1.0f,  1.0f };struct SampleWindow : DesktopWindow{    ComPtr
      
        m_brush;    void CreateDeviceResources()    {        m_target->CreateSolidColorBrush(COLOR_BLUE,             m_brush.ReleaseAndGetAddressOf());    }    void Draw()    {        m_target->Clear(COLOR_BLUE);        auto size = m_target->GetSize();        m_brush->SetOpacity(1.0f);                m_brush->SetColor(COLOR_BLACK);        auto br = RectF(100.0f, 100.0f, size.width - 100.0f, 200.0f);        m_target->FillRectangle(br, m_brush.Get());        m_brush->SetColor(COLOR_WHITE);        auto bw = RectF(100.0f, 300.0f, size.width - 100.0f, 400.0f);        m_target->FillRectangle(bw, m_brush.Get());        m_brush->SetOpacity(.5f);        m_brush->SetColor(COLOR_YELLOW);        auto ry = RectF(150.0f, 150.0f, size.width - 150.0f, 350.0f);        m_target->FillRectangle(ry, m_brush.Get());    }};int __stdcall wWinMain(HINSTANCE, HINSTANCE, PWSTR, int){    SampleWindow window;        window.Run();}
      

 线性渐变画笔（LinearGradientBrush）稍微麻烦，需要先定义关键点（D2D1_GRADIENT_STOP），然后将关键点加入渐变集合（ID2D1GradientStopCollection），最后将渐变集合定义为渐变画笔，其示例如下所示： 

#include "Precompiled.h"#include "DesktopWindow.h"D2D_COLOR_F const COLOR_BLUE    = { 0.26f, 0.56f, 0.87f, 1.0f };D2D_COLOR_F const COLOR_WHITE    = { 1.0f,  1.0f,  1.0f,  1.0f };struct SampleWindow : DesktopWindow
      
       {    ComPtr
       
         m_brush;    void CreateDeviceResources()    {        D2D1_GRADIENT_STOP stops[] =         {            { 0.0f, COLOR_WHITE },             { 1.0f, COLOR_BLUE }        };        ComPtr
        
          collection;        m_target->CreateGradientStopCollection(stops, _countof(stops),             collection.GetAddressOf());        D2D1_LINEAR_GRADIENT_BRUSH_PROPERTIES props = {};        m_target->CreateLinearGradientBrush(props, collection.Get(),             m_brush.ReleaseAndGetAddressOf());    }    void Draw()    {        auto size = m_target->GetSize();        m_brush->SetEndPoint(Point2F(size.width, size.height));                auto r = RectF(0.0f, 0.0f, size.width, size.height);        m_target->FillRectangle(r, m_brush.Get());    }};int __stdcall wWinMain(HINSTANCE, HINSTANCE, PWSTR, int){    SampleWindow window;        window.Run();}
        
       
      

 可以使用环形渐变画笔（RadialGradientBrush），其定义方法和线性渐变画笔类似，也是定义关键点、渐变集合（COM），然后再定义渐变画笔，其救命如下所示：

#include "Precompiled.h"#include "DesktopWindow.h"D2D1_COLOR_F const COLOR_BLUE    = { 0.26f, 0.56f, 0.87f, 1.0f };D2D_COLOR_F const COLOR_WHITE     = { 1.0f,  1.0f,  1.0f,  1.0f };struct SampleWindow : DesktopWindow
      
       {    ComPtr
       
         m_brush;    void CreateDeviceResources()    {        D2D1_GRADIENT_STOP stops[] =         {            { 0.0f, COLOR_WHITE },             { 1.0f, COLOR_BLUE }        };        ComPtr
        
          collection;        m_target->CreateGradientStopCollection(stops, _countof(stops),            collection.GetAddressOf());        D2D1_RADIAL_GRADIENT_BRUSH_PROPERTIES props = {};        m_target->CreateRadialGradientBrush(props, collection.Get(),             m_brush.ReleaseAndGetAddressOf());    }    void Draw()    {        auto size = m_target->GetSize();        m_brush->SetCenter(Point2F(size.width / 2.0f, size.height / 2.0f));        m_brush->SetRadiusX(size.width / 2.0f);        m_brush->SetRadiusY(size.height / 2.0f);        auto r = RectF(0.0f, 0.0f, size.width, size.height);        m_target->FillRectangle(r, m_brush.Get());    }};int __stdcall wWinMain(HINSTANCE, HINSTANCE, PWSTR, int){    SampleWindow window;        window.Run();}
        
       
      

 在创建渐变集合时（CreateGradientStopCollection），可以设置D2D1_GAMMA_1_0或者D2D1_GAMMA_2_2，默认是D2D1_GAMMA_2_2，具体区别如下图所示（上图为2.2），直观上的区别就是D2D1_GAMMA_2_2的渐变性更好。

最后，还可以通过设置边框样式（ID2D1StrokeStyle）来显示各种边框，注意边框样式是独立于设备的资源，因此，只需将边框样式的定义放在CreateDeviceIndependentResources方法中即可：

#include "Precompiled.h"#include "DesktopWindow.h"D2D1_COLOR_F const COLOR_BLUE    = { 0.26f, 0.56f, 0.87f, 1.0f };D2D_COLOR_F const COLOR_WHITE     = { 1.0f,  1.0f,  1.0f,  1.0f };struct SampleWindow : DesktopWindow
      
       {    ComPtr
       
         m_brush;    ComPtr
        
          m_style;    void CreateDeviceIndependentResources()    {        D2D1_STROKE_STYLE_PROPERTIES props = {};        props.lineJoin = D2D1_LINE_JOIN_ROUND;        props.dashStyle = D2D1_DASH_STYLE_DASH_DOT;        props.dashCap = D2D1_CAP_STYLE_ROUND;        m_factory->CreateStrokeStyle(props, nullptr, 0, m_style.GetAddressOf());    }    void CreateDeviceResources()    {        m_target->CreateSolidColorBrush(COLOR_WHITE,             m_brush.ReleaseAndGetAddressOf());    }    void Draw()    {        m_target->Clear(COLOR_BLUE);        auto size = m_target->GetSize();                auto r = RectF(100.0f, 100.0f, size.width - 100.0f, size.height - 100.0f);        m_target->DrawRectangle(r, m_brush.Get(), 20.0f, m_style.Get());    }};int __stdcall wWinMain(HINSTANCE, HINSTANCE, PWSTR, int){    SampleWindow window;        window.Run();}