《基于MFC的OpenGL编程》Part 15 Reflection

《基于MFC的OpenGL编程》Part 16 Reflection

    原文链接

    源码链接

Reflections

Adding reflections to a program too can improve its realism to a great extent. Here we'll look at a simple method to create reflection where we simply redraw the object with an appropriate transformation and make the surface in between translucent. This creates an effective illusion of reflection!!

1、设置光源代码(主要是参数的修改)修改如下：

void CMy2OpenGLView::SetupLighting(){//Material PropertiesGLfloat matSpecular[] = {1.0f,0.0f,0.0f,0.7f};//反射材质特性GLfloat matShininess[] = {50.0f};//镜面反射指数特性GLfloat matAmbient[] =  {0.25f,0.25f,0.25f,0.7f};//周围环境特性GLfloat matDiffuse[] = {0.5f,0.5f,0.5f,0.7f};//散射特性glMaterialfv(GL_FRONT,GL_SPECULAR,matSpecular);glMaterialfv(GL_FRONT,GL_SHININESS,matShininess);glMaterialfv(GL_FRONT,GL_AMBIENT,matAmbient);glMaterialfv(GL_FRONT,GL_DIFFUSE,matDiffuse);//Lighting Parameters//Enable Lighting glEnable(GL_LIGHTING);//Specify a single directional light GLfloat ambient1[] = {0.5f,0.5f,0.5f};GLfloat diffuse1[] = {0.5f,0.5f,0.5f};GLfloat specular1[] = {1.0f,0.0f,0.0f};GLfloat position1[] = {0.0f,0.0f,5.0f,0.0f};glLightfv(GL_LIGHT0,GL_AMBIENT,ambient1);glLightfv(GL_LIGHT0,GL_DIFFUSE,diffuse1);glLightfv(GL_LIGHT0,GL_SPECULAR,specular1);glLightfv(GL_LIGHT0,GL_POSITION,position1);glEnable(GL_LIGHT0);//Specify a single positional spotlightGLfloat ambient2[] = {1.0f,1.0f,0.0f};GLfloat diffuse2[] = {1.0f,0.0f,0.0f};GLfloat position2[] = {1.0f,0.0f,5.0f,1.0f};GLfloat direction2[] = {0.0f,0.0f,-5.0f};glLightfv(GL_LIGHT1,GL_AMBIENT,ambient2);glLightfv(GL_LIGHT1,GL_DIFFUSE,diffuse2);glLightfv(GL_LIGHT1,GL_POSITION,position2);glLightfv(GL_LIGHT1,GL_SPOT_DIRECTION,direction2);glLightf(GL_LIGHT1,GL_SPOT_CUTOFF,15.0f);glEnable(GL_LIGHT1);}

2、绘制函数void CMy2OpenGLView::RenderScene3D() 修改如下：

if (m_bCubeTexture)//画一个纹理自旋立方体{glLoadIdentity();//立方体中心移至坐标系原点        glTranslatef(0.0f,-0.0f,-8.0f);//this is the position of the cube，//so the parameter should be proper，then we can see the cube  //save the matrix and do the rotation glPushMatrix();glRotatef(m_xRot,1.0f,0.0f,0.0f); glCallList(m_sceneList);////////////glPopMatrix();glPushMatrix();glTranslatef(0.0f,-3.0f,0.0f);glScalef(1.0f,-1.0f,1.0f);glRotatef(m_xRot,1.0f,0.0f,0.0f);  glCallList(m_sceneList);<span style="font-family: 宋体;">////////////////////////</span>glPopMatrix();//Draw bottom of floorglEnable(GL_BLEND);glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);glPushMatrix();glEnable(GL_TEXTURE_2D);glBindTexture(GL_TEXTURE_2D,m_Texture[3]);//set background of the floorglBegin(GL_POLYGON);glTexCoord2f(0.0f,0.0f);glVertex3f(-5.0f,-1.5f,5.0f);glTexCoord2f(1.0f,0.0f);glVertex3f(-5.0f,-1.5f,-5.0f);glTexCoord2f(1.0f,1.0f);glVertex3f(5.0f,-1.5f,-5.0f);glTexCoord2f(0.0f,1.0f);glVertex3f(5.0f,-1.5f,5.0f);  glEnd(); glPopMatrix();glDisable(GL_TEXTURE_2D);glDisable(GL_BLEND);     //    glRotatef(m_yRot,0.0f,1.0f,0.0f);// glCallList(m_sceneList);}

3、修改函数CMy2OpenGLView::CreateSceneList()（该函数画自旋立方体，将其添加到列表函数中）：

void CMy2OpenGLView::CreateSceneList(){//创建显示列表    m_sceneList = glGenLists(1);glNewList(m_sceneList,GL_COMPILE);//SetupLighting();glEnable(GL_TEXTURE_2D);glShadeModel(GL_SMOOTH);LoadGLTextures();glBindTexture(GL_TEXTURE_2D,m_Texture[0]);//Front Face        glBegin(GL_POLYGON);            glTexCoord2f(0,0);            glVertex3f(-1.0f,-1.0f,0.0f);            glTexCoord2f(1,0);            glVertex3f( 1.0f,-1.0f,0.0f);            glTexCoord2f(1,1);            glVertex3f( 1.0f, 1.0f,0.0f);            glTexCoord2f(0,1);            glVertex3f(-1.0f, 1.0f,0.0f);        glEnd();        //Back Face        glBegin(GL_POLYGON);            glTexCoord2f(1,0);            glVertex3f(-1.0f,-1.0f,-1.0f);            glTexCoord2f(1,1);            glVertex3f(-1.0f, 1.0f,-1.0f);            glTexCoord2f(0,1);            glVertex3f( 1.0f, 1.0f,-1.0f);            glTexCoord2f(0,0);            glVertex3f( 1.0f,-1.0f,-1.0f);        glEnd();        glBindTexture(GL_TEXTURE_2D,m_Texture[1]);        //Left Face        glBegin(GL_POLYGON);            glTexCoord2f(1,0);            glVertex3f(-1.0f,-1.0f, 0.0f);            glTexCoord2f(1,1);            glVertex3f(-1.0f, 1.0f, 0.0f);            glTexCoord2f(0,1);            glVertex3f(-1.0f, 1.0f,-1.0f);            glTexCoord2f(0,0);            glVertex3f(-1.0f,-1.0f,-1.0f);        glEnd();        //Right Face        glBegin(GL_POLYGON);            glTexCoord2f(0,0);            glVertex3f(1.0f,-1.0f, 0.0f);            glTexCoord2f(1,0);            glVertex3f(1.0f,-1.0f,-1.0f);            glTexCoord2f(1,1);            glVertex3f(1.0f, 1.0f,-1.0f);            glTexCoord2f(0,1);            glVertex3f(1.0f, 1.0f, 0.0f);        glEnd();        glBindTexture(GL_TEXTURE_2D,m_Texture[2]);        //Top Face        glBegin(GL_POLYGON);            glTexCoord2f(0,0);            glVertex3f(-1.0f, 1.0f,  0.0f);            glTexCoord2f(0,1);            glVertex3f( 1.0f, 1.0f,  0.0f);            glTexCoord2f(1,1);            glVertex3f( 1.0f, 1.0f, -1.0f);            glTexCoord2f(1,0);            glVertex3f(-1.0f, 1.0f, -1.0f);        glEnd();        //Bottom Face        glBegin(GL_POLYGON);            glTexCoord2f(0,1);            glVertex3f(-1.0f, -1.0f,  0.0f);            glTexCoord2f(0,0);            glVertex3f(-1.0f, -1.0f, -1.0f);            glVertex3f( 1.0f, -1.0f, -1.0f);            glTexCoord2f(1,1);            glVertex3f( 1.0f, -1.0f,  0.0f);        glEnd();        glDisable(GL_TEXTURE_2D);glEndList();//this is important}

4、加上大理石纹理：

void CMy2OpenGLView::LoadGLTextures(){    //Create Texture Names    glGenTextures(4, m_Texture);    LoadTexture("Apple.bmp",0);    LoadTexture("Fauve.bmp",1);    LoadTexture("Flower.bmp",2);    LoadTexture("Floor.bmp",3);}

运行效果,估计是SetLighting的参数原因，没有明显的Reflection效果：