齐硕换热器:AGG 成果

作为本文的结尾，这里放上一个用AGG生成不规则文字窗体的代码。它综合了我们之前学到的AGG字体引擎、坐标转换、颜色渐变等几大模 块。由于AGG的抗锯齿特性，使用生 成的窗体看上去边缘过渡非常自然，几乎看不到“毛边”。

先放上最终生成的窗体的效果：

貌似比网页左上角的logo还要好看那么一点点-_-

1. #define _WIN32_WINNT 0x0501
2. #include
3. #include
4. #include
5. #include
6. #include
7. #include <../font_win32_tt/agg_font_win32_tt.h>
8. #include
9. #include
10. #include
11. #include
12. #include
13. #include
14. #include
15. #include
17. typedef agg::font_engine_win32_tt_int16 fe_type;
18. typedef agg::font_cache_manager fcman_type;
19. typedef agg::renderer_base renb_type;
21. // 使用指定的顶点源和线段生成器输出文字
22. template
23. void AggDrawText(renb_type &renb,
24.                   fcman_type &font_manager,
25.                   VS &vs, SpanGenerator &span_gen,
26.                  const wchar_t *txt)
27. {
28.     using namespace agg;
29.     
30.      span_allocator span_alloc;
31.      rasterizer_scanline_aa<> ras;
32.      scanline_u8 sl;
33.     
34.     double x=0, y=0;
35.     for(const wchar_t *p = txt; *p; p++)
36.      {
37.         const glyph_cache* gc = font_manager.glyph(*p);
38.         if(gc)
39.          {
40.              font_manager.init_embedded_adaptors(gc, x, y);
42.              ras.add_path(vs);
43.              agg::render_scanlines_aa(ras, sl, renb, span_alloc, span_gen);
45.              x += gc->advance_x;
46.              y += gc->advance_y;
47.          }
48.      }
49. }
51. // 向renb的指定位置和半径输出http://www.cppprog.com ,有环绕效果
52. void DrawUrl(HDC dc, renb_type &renb,
53.              double ox, double oy, double rx, double ry)
54. {
55.     using namespace agg;
56.     //字体引擎
57.      fe_type font(dc);
58.      fcman_type font_manager(font);
59.      font.height(18.0);
60.      font.flip_y(true);
61.      font.hinting(true);
62.     if(!font.create_font("Comic Sans MS",agg::glyph_ren_outline)) return;
63.     //坐标转换管道
64.     typedef conv_curve<
65.          fcman_type::path_adaptor_type
66.      > cc_pa_type;
67.      cc_pa_type ccpath(font_manager.path_adaptor());
69.     typedef conv_transform         trans_single_path> ct_cc_pa_type;
70.      trans_single_path trans_path;
71.      ct_cc_pa_type ctpath(ccpath, trans_path);
72.     
73.      ellipse ell(0,0,rx,ry);
74.      trans_affine ellmtx;
75.      conv_transform ctell(ell, ellmtx);
76.      ellmtx.rotate(agg::pi);
77.      ellmtx.translate(ox,oy);
78.      trans_path.add_path(ctell);
79.     // 线段生成器
80.      span_solid ss;
81.      ss.color(rgba(1,0,0));
83.      AggDrawText(renb, font_manager, ctpath, ss, L"http://www.cppprog.com");
84. }
85. // 向renb的指定位置输出“C++编程”几个字，有镜象效果
86. void DrawName(HDC dc, renb_type &renb, double x, double y)
87. {
88.     using namespace agg;
89.     // 字体引擎
90.      fe_type font(dc);
91.      fcman_type font_manager(font);
93.      font.height(30.0);
94.      font.flip_y(true);
95.      font.hinting(true);
96.     if(!font.create_font("黑体",agg::glyph_ren_outline)) return;
97.     // 坐标转换管道
98.     typedef conv_curve<
99.          fcman_type::path_adaptor_type
100.      > cc_pa_type;
101.      cc_pa_type ccpath(font_manager.path_adaptor());
103.     typedef conv_transform ct_cc_pa_type;
104.      trans_affine mtx;
105.      ct_cc_pa_type ctpath( ccpath, mtx );
107.      mtx.translate(50,50);
108.     //线段生成器
109.      span_solid ss;
110.      ss.color(rgba(0,0,0));
112.      AggDrawText(renb, font_manager, ctpath, ss, L"C++编程");
113.     // 改变坐标转换矩阵(镜像)
114.      mtx.reset();
115.      mtx.flip_y();
116.      mtx.translate(50,60);
118.     // 渐变线段生成器
119.     typedef span_interpolator_linear<> interpolator_type;
120.      trans_affine img_mtx;
121.      interpolator_type ip(img_mtx);
123.     typedef gradient_y gradientF_type;
124.      gradientF_type grF;
126.     typedef gradient_linear_color colorF_type;
127.      colorF_type colorF(rgba(0,0,0), rgba(0,0,0,0));
128.     
129.     typedef span_gradient         interpolator_type,
130.          gradientF_type,
131.          colorF_type> span_gen_type;
132.      span_gen_type span_gen(ip,grF,colorF,30,80);
133.     
134.      AggDrawText(renb, font_manager, ctpath, span_gen, L"C++编程");
135. }
136. // 调用DrawUrl和DrawName向renb输出文字
137. void DrawIt(HDC dc, renb_type &renb)
138. {
139.     // 以透明色填充
140.      renb.clear(rgba(0,0,0,0));
141.     // 输出文字
142.      DrawUrl(dc, renb, 100, 50, 80, 40);
143.      DrawName(dc, renb, 50, 50);
144. }
145. // 使用AGG处理图片后与hwnd关联
146. void SetLayoutWin(HWND hwnd)
147. {
148.     // 起始位置和窗体大小
149.      POINT ptWinPos = {500,200};
150.      SIZE sizeWindow = {200, 100};
152.     // 建立DIB
153.      BITMAPINFO bmp_info;
154.      ::ZeroMemory(&bmp_info, sizeof(bmp_info));
155.      bmp_info.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
156.      bmp_info.bmiHeader.biWidth = sizeWindow.cx;
157.      bmp_info.bmiHeader.biHeight = sizeWindow.cy;
158.      bmp_info.bmiHeader.biPlanes = 1;
159.      bmp_info.bmiHeader.biBitCount = 32;
160.      bmp_info.bmiHeader.biCompression = BI_RGB;
161.     
162.     HDC hdcTemp = GetDC(0);
163.     HDC mem_dc = ::CreateCompatibleDC(hdcTemp);
164.      ReleaseDC(0, hdcTemp);
166.     void* buf = NULL;
167.     HBITMAP bmp = ::CreateDIBSection(
168.          mem_dc,
169.          &bmp_info,
170.          DIB_RGB_COLORS,
171.          &buf,
172.          0, 0
173.      );
174.     
175.     // 把bmp与mem_dc关联，这样AGG就可以和原生GDI一起工作了
176.     HBITMAP temp = (HBITMAP)::SelectObject(mem_dc, bmp);
177.      {
178.         // AGG处理
179.          agg::rendering_buffer rbuf(
180.              (unsigned char*)buf,
181.              sizeWindow.cx, sizeWindow.cy,
182.              -sizeWindow.cx*4);
183.          agg::pixfmt_bgra32 pixf(rbuf);
184.          renb_type renb(pixf);
185.          DrawIt(mem_dc,renb);
186.      }
188.     // 把画好的mem_dc与hwnd关联到一起
189.      BLENDFUNCTION m_Blend={AC_SRC_OVER,0,255,AC_SRC_ALPHA};
190.      POINT ptSrc = {0, 0};
191.     BOOL bRet = UpdateLayeredWindow(hwnd, 0, &ptWinPos,
192.                                      &sizeWindow, mem_dc, &ptSrc,
193.                                      0, &m_Blend, ULW_ALPHA);
194.     // 回收
195.      ::DeleteObject(bmp);
196.      ::DeleteDC(mem_dc);
197. }
199. // Windows消息处理
200. LRESULT CALLBACK WndProc (HWND hwnd, UINT umsg, WPARAM wParam,
201.                           LPARAM lParam)
202. {
203.   switch (umsg)
204.    {
205.     case WM_CLOSE:
206.        DestroyWindow (hwnd);
207.       return 0;
208.     case WM_DESTROY:
209.        PostQuitMessage (0);
210.       return 0;
211.     case WM_NCHITTEST:
212.       return HTCAPTION;
213.    }
214.   return DefWindowProc (hwnd, umsg, wParam, lParam);
215. }
217. int APIENTRY WinMain(HINSTANCE hInstance,
218.                      HINSTANCE hPrevInstance,
219.                      LPTSTR     lpCmdLine,
220.                      int        nCmdShow)
221. {
222.      WNDCLASS wc={
223.          0,WndProc,
224.          0,0,
225.          hInstance,
226.          NULL,LoadCursor(NULL, IDC_ARROW),
227.          (HBRUSH)(COLOR_WINDOW+1),
228.          0,"AGGWIN"
229.      };
230.      ::RegisterClass(&wc);
232.     HWND hWnd = ::CreateWindowEx(WS_EX_LAYERED,"AGGWIN", NULL, WS_OVERLAPPEDWINDOW,
233.        CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);
235.     if (!hWnd) return -1;
236.      SetLayoutWin(hWnd);
237.      ::ShowWindow(hWnd, nCmdShow);
239.     // 主消息循环:
240.      MSG msg;
241.     while (GetMessage(&msg, NULL, 0, 0))
242.      {
243.          TranslateMessage(&msg);
244.          DispatchMessage(&msg);
245.      }
247.     return (int) msg.wParam;
248. }