OSG文字-各种文字效果(边框、阴影及颜色倾斜)示例（2）
- 各种文字效果(边框、阴影及颜色倾斜)示例
各种文字效果(边框、阴影及颜色倾斜)示例的代码如程序清单9-2所示：
1. /* 各种文字效果(边框、阴影及颜色倾斜)示例 */
2. osg::ref_ptr<osg::Camera> createAllKindText(const string &strDataFolder)
3. {
4. osg::ref_ptr<osg::Camera> camera = new osg::Camera();
5.
6. // 设置投影矩阵
7. camera->setProjectionMatrix(osg::Matrix::ortho2D(0, 1280, 0, 800));
8.
9. // 设置视图矩阵
10. camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
11. camera->setViewMatrix(osg::Matrix::identity());
12.
13. // 清除深度缓存
14. camera->setClearMask(GL_DEPTH_BUFFER_BIT);
15.
16. // 设置渲染顺序，在主摄像机之前渲染
17. camera->setRenderOrder(osg::Camera::POST_RENDER);
18.
19. // 设置为不接收事件，始终不得到焦点
20. camera->setAllowEventFocus(false);
21.
22. string strFontPath = strDataFolder + "fonts\\arial.ttf";
23. osg::ref_ptr<osgText::Font> font = osgText::readFontFile(strFontPath);
24. osg::ref_ptr<osg::Geode> geode = new osg::Geode;
25.
26. osg::ref_ptr<osg::StateSet> stateset = geode->getOrCreateStateSet();
27. stateset->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
28.
29. //--------------------------------------------------------------------
30. // 设置文字的输出的格式
31.
32. // 设置格式为LEFT_TO_RIGHT,从左到右
33. {
34. osg::ref_ptr<osgText::Text> text = new osgText::Text;
35. text->setFont(font.get());
36. text->setColor(osg::Vec4(1.0, 1.0, 0.0, 1.0));
37. text->setCharacterSize(20.0);
38. text->setPosition(osg::Vec3(50.0, 750.0, 0.0));
39. text->setLayout(osgText::Text::LEFT_TO_RIGHT);
40. text->setText("text->setLayout(osgText::Text::LEFT_TO_RIGHT);");
41. geode->addDrawable(text.get());
42. }
43. // 设置格式为RIGHT_TO_LEFT，从右到左
44. {
45. osg::ref_ptr<osgText::Text> text = new osgText::Text;
46. text->setFont(font.get());
47. text->setColor(osg::Vec4(1.0, 1.0, 0.0, 1.0));
48. text->setCharacterSize(30.0);
49. text->setPosition(osg::Vec3(1200.0, 750.0, 0.0));
50.
51. text->setLayout(osgText::Text::RIGHT_TO_LEFT);
52. text->setAlignment(osgText::Text::RIGHT_BASE_LINE);
53.
54. text->setText("text->setLayout(osgText::Text::RIGHT_TO_LEFT); ");
55.
56. geode->addDrawable(text.get());
57. }
58. // 设置格式为VERTICAL，垂直
59. {
60. osg::ref_ptr<osgText::Text> text = new osgText::Text;
61. text->setFont(font.get());
62. text->setColor(osg::Vec4(1.0, 1.0, 0.0, 1.0));
63. text->setCharacterSize(20.0);
64. text->setPosition(osg::Vec3(50.0, 750.0, 0.0));
65. text->setLayout(osgText::Text::VERTICAL);
66. text->setText("text->setLayout(osgText::Text::VERTICAL);");
67. geode->addDrawable(text.get());
68. }
69. //--------------------------------------------------------------------
70. // 设置阴影
71. {
72. osg::ref_ptr<osgText::Text> text = new osgText::Text;
73. text->setFont(font.get());
74. text->setColor(osg::Vec4(1.0, 1.0, 0.0, 1.0));
75. text->setCharacterSize(40.0);
76. text->setPosition(osg::Vec3(100.0, 650.0, 0.0));
77.
78. // 设置阴影为DROP_SHADOW_BOTTOM_RIGHT
79. text->setBackdropType(osgText::Text::DROP_SHADOW_BOTTOM_RIGHT);
80. text->setBackdropColor(osg::Vec4(0.0, 1.0, 0.0, 1.0));
81. text->setBackdropOffset(0.1, -0.1);
82. text->setText("text->setBackdropType(osgText::Text::DROP_SHADOW_BOTTOM_RIGHT);");
83. geode->addDrawable(text.get());
84. }
85.
86. //--------------------------------------------------------------------
87. // 设置边框
88. {
89. osg::ref_ptr<osgText::Text> text = new osgText::Text;
90. text->setFont(font.get());
91. text->setColor(osg::Vec4(1.0, 1.0, 0.0, 1.0));
92. text->setCharacterSize(30.0);
93. text->setPosition(osg::Vec3(100.0, 450.0, 0.0));
94.
95. // 设置边框对齐绘制
96. text->setDrawMode(osgText::Text::TEXT | osgText::Text::BOUNDINGBOX|osgText::Text::ALIGNMENT);
97. text->setText("text->setDrawMode(osgText::Text::TEXT | osgText::Text::BOUNDINGBOX|osgText::Text::ALIGNMENT);");
98. geode->addDrawable(text.get());
99. }
100.
101. //-------------------------------------------------------------------
102. // 设置颜色倾斜模式
103. {
104. osg::ref_ptr<osgText::Text> text = new osgText::Text;
105. text->setFont(font.get());
106. text->setColor(osg::Vec4(1.0, 1.0, 0.0, 1.0));
107. text->setCharacterSize(40.0);
108. text->setPosition(osg::Vec3(100.0, 250.0, 0.0));
109.
110. // 设置颜色倾斜模式为：PER_CHARCTER
111. text->setColorGradientMode(osgText::Text::PER_CHARACTER);
112.
113. // 设置倾斜4个角落的颜色
114. text->setColorGradientCorners(osg::Vec4(1.0,0.0,0.0,1.0),osg::Vec4(0.0,1.0,0.0,1.0),
115. osg::Vec4(0.0,0.0,1.0,1.0),osg::Vec4(1.0,1.0,1.0,1.0));
116. text->setText("text->setColorGradientMode(osgText::Text::SOLID);");
117. geode->addDrawable(text.get());
118. }
119.
120. camera->addChild(geode.get());
121.
122. return camera.get();
123. }
124.
125. void osgText_9_2(const string &strDataFolder)
126. {
127. osg::ref_ptr<osgViewer::Viewer> viewer = new osgViewer::Viewer();
128. osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
129. traits->x = 40;
130. traits->y = 40;
131. traits->width = 600;
132. traits->height = 480;
133. traits->windowDecoration = true;
134. traits->doubleBuffer = true;
135. traits->sharedContext = 0;
136.
137. osg::ref_ptr<osg::GraphicsContext> gc = osg::GraphicsContext::createGraphicsContext(traits.get());
138.
139. //osg::ref_ptr<osg::Camera> camera = new osg::Camera;
140.
141.
142. // 创建各种文字效果
143. osg::ref_ptr<osg::Camera> camera = createAllKindText(strDataFolder);
144. camera->setGraphicsContext(gc.get());
145. camera->setViewport(new osg::Viewport(0, 0, traits->width, traits->height));
146. GLenum buffer = traits->doubleBuffer ? GL_BACK : GL_FRONT;
147. camera->setDrawBuffer(buffer);
148. camera->setReadBuffer(buffer);
149.
150. viewer->addSlave(camera.get());
151.
152. // 添加到根节点
153. osg::ref_ptr<osg::Group> root = new osg::Group();
154. root->addChild(createAllKindText(strDataFolder));
155.
156. // 优化场景数据
157. osgUtil::Optimizer optimizer;
158. optimizer.optimize(root.get());
159.
160. viewer->setSceneData(root.get());
161.
162. viewer->realize();
163.
164. viewer->run();
165. }
运行程序，截图如图9-4所示
图9-4 各种文字效果(边框、阴影及颜色倾斜)示例截图