Osg-OsgShader着色器(Qt5.14.2+osgE3.6.5+win10)-No16-OsgShader

.pro
 1 QT       += core gui widgets
 2 TARGET = TestOsgQt
 3 TEMPLATE = app
 4 DEFINES += QT_DEPRECATED_WARNINGS
 5 CONFIG += c++11
 6 
 7 QMAKE_CXXFLAGS_RELEASE = $$QMAKE_CFLAGS_RELEASE_WITH_DEBUGINFO
 8 QMAKE_LFLAGS_RELEASE = $$QMAKE_LFLAGS_RELEASE_WITH_DEBUGINFO
 9 
10 SOURCES += \
11         main.cpp
12 
13 HEADERS +=
14 
15 OsgDir = D:\\Gitee\\osg365R
16 CONFIG(release, debug|release) {
17         LIBS += -L$${OsgDir}/lib/ -losgDB -losgViewer -lOpenThreads -losgAnimation -losg \
18                                   -losgEarth -losgEarthAnnotation -losgEarthFeatures -losgEarthSymbology -losgEarthUtil \
19                                   -losgQOpenGL -losgUtil -losgText -losgTerrain -losgSim \
20                                   -losgShadow -losgParticle -losgManipulator -losgGA -losgFX \
21                                   -losgWidget
22 } else {
23         LIBS += -L$${OsgDir}/debug/lib/ -losgDBd -losgViewerd -lOpenThreadsd -losgAnimationd -losgd \
24                                   -losgEarthd -losgEarthAnnotationd -losgEarthFeaturesd -losgEarthSymbologyd -losgEarthUtild \
25                                   -losgQOpenGLd -losgUtild -losgTextd -losgTerraind -losgSimd \
26                                   -losgShadowd -losgParticled -losgManipulatord -losgGAd -losgFXd \
27 }
28 
29 
30 INCLUDEPATH += $${OsgDir}/include
31 DEPENDPATH += $${OsgDir}/include
View Code

main.cpp

 1 #include <osg/Program>
 2 #include <osgDB/ReadFile>
 3 #include <osgViewer/Viewer>
 4 
 5  static const char* vertSource = {
 6      "varying vec3 normal;"//易变量 用于着色器之间的传值
 7      "void main()"
 8      "{"
 9      "    normal = normalize(gl_NormalMatrix * gl_Normal);" //把法线向量从物体空间转化到视觉空间。
10      "    gl_Position = ftransform();" //相当于 gl_Position = ModelViewProjectionMatrix * gl_Vertex,
11                                                  //模型视图投影矩阵与空间顶点位置相乘，得到裁剪空间顶点位置。
12      "}"
13  };
14 
15  static const char* fragSource = {
16      "uniform vec4 mainColor;"  //外面程序输入的颜色
17      "varying vec3 normal;"    //上面的顶点着色器传的法线
18      "void main()"
19      "{"
20      "    float intensity = dot(vec3(gl_LightSource[0].position), normal);" //计算光照位置与法线的点积，为什么这么做，知道的朋友不吝赐教下。
21                                                                              //按照我的理解就是计算了一下亮度值。
22      //给输出的颜色赋值
23      "    if (intensity > 0.95) gl_FragColor = mainColor;" //如果这个值大于0.95，则输出颜色为mainColor，而uniform回调中每帧在来回改这个值，所
24                                                              //以这一部分会出现闪烁的效果。
25      "    else if (intensity > 0.5) gl_FragColor = vec4(0.6,0.3,0.3,1.0);"
26      "    else if (intensity > 0.25) gl_FragColor = vec4(0.4,0.2,0.2,1.0);"
27      "    else gl_FragColor = vec4(0.2,0.1,0.1,1.0);"
28      "}"
29  };
30 
31 
32  /* 一直变量uniform回调类，主要用于每帧更新着色器中的用户数据，从而改变渲染的行为和输出结果。     */
33 
34 
35  class ColorCallback : public osg::Uniform::Callback
36  {
37  public:
38      ColorCallback() : _incRed(false) {}
39 
40      virtual void operator()( osg::Uniform* uniform, osg::NodeVisitor* nv )
41      {
42          if ( !uniform ) return;
43 
44          osg::Vec4 color;
45          uniform->get( color );//获取通过uniform 设置进去的值mainColor
46 
47          if ( _incRed==true )//3、如果r减到0呢，就给他一直加。
48          {
49              if ( color.x()<1.0 ) color.x() += 0.1;
50              else _incRed = false;//4、如果加到1就给他再减。
51          }
52          else
53          {
54              if ( color.x()>0.0 ) color.x() -= 0.1;//1、如果RGB中的r分量大于0，则一直减小。
55              else _incRed = true;// 2、r减到0了。
56          }
57          uniform->set( color );
58      }
59 
60  protected:
61      bool _incRed;
62  };
63 
64  void createShaders( osg::StateSet& ss )
65  {
66      osg::ref_ptr<osg::Shader> vertShader = new osg::Shader( osg::Shader::VERTEX, vertSource );
67      osg::ref_ptr<osg::Shader> fragShader = new osg::Shader( osg::Shader::FRAGMENT, fragSource );
68 
69      osg::ref_ptr<osg::Program> program = new osg::Program;
70      program->addShader( vertShader.get() );
71      program->addShader( fragShader.get() );
72 
73      osg::ref_ptr<osg::Uniform> mainColor = new osg::Uniform( "mainColor", osg::Vec4(0.5,0.5,0.5,1.0) );//这个部分的颜色是闪烁部分的颜色值。
74      mainColor->setUpdateCallback( new ColorCallback );
75 
76      ss.addUniform( mainColor.get() );
77      ss.setAttributeAndModes( program.get() );
78  }
79 
80  int main( int argc, char** argv )
81  {
82      osg::ArgumentParser arguments( &argc, argv );
83      osg::Node* model = osgDB::readNodeFiles( arguments );
84      if ( !model ) model = osgDB::readNodeFile( "D:\\Gitee\\data\\cow.osg" );
85 
86      createShaders( *(model->getOrCreateStateSet()) );
87 
88      osgViewer::Viewer viewer;
89      viewer.setSceneData( model );
90      viewer.setUpViewInWindow(20,20,600,600);
91      return viewer.run();
92  }
View Code

 

 

posted on 2022-07-12 18:43  疯狂delphi  阅读(41)  评论(0)  编辑  收藏  举报

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