本文在第11篇文章的基礎上，為其加入顯示各種二次曲面的代碼；
Quadrics
Every quadric has a few settings associated with it. We have to create a quadric first and then customize its settings to render the shape we want. The gluNewQuadric function creates a state variable that describes the current drawing style, orientation, lighting mode, texturing mode and the callback functions. Once we use this function to create a new quadric, we can customize the drawing of shapes by changing its state using functions such as
gluQuadricDrawStyle - which selects the type of OpenGL drawing primitives that are used to drw the shape.
gluQuadricOrientation - which controls the direction of the lighting normals.
gluQuadricNormals - which controls the generation of lighting normals.
gluQuadricTexture - which generates texture coordinates automatically for the quadric.
1,在CCY457OpenGLView類中加入下列變量，用來表示二次曲面類型：
//Quadric
GLuint m_Quadric;
2，加入四個控制二次曲面類型的菜單項及其事件處理函數
void CCY457OpenGLView::OnQuadricSphere()
{//球體
m_Quadric = 0;
InvalidateRect(NULL,FALSE);
}
void CCY457OpenGLView::OnUpdateQuadricSphere(CCmdUI* pCmdUI)
{
if(m_Quadric == 0)
pCmdUI->SetRadio(TRUE);
else
pCmdUI->SetRadio(FALSE);
}
void CCY457OpenGLView::OnQuadricCone()
{//圓錐
m_Quadric = 2;
InvalidateRect(NULL,FALSE);
}
void CCY457OpenGLView::OnUpdateQuadricCone(CCmdUI* pCmdUI)
{
if(m_Quadric == 2)
pCmdUI->SetRadio(TRUE);
else
pCmdUI->SetRadio(FALSE);
}
void CCY457OpenGLView::OnQuadricCylinder()
{//柱體
m_Quadric = 1;
InvalidateRect(NULL,FALSE);
}
void CCY457OpenGLView::OnUpdateQuadricCylinder(CCmdUI* pCmdUI)
{
if(m_Quadric == 1)
pCmdUI->SetRadio(TRUE);
else
pCmdUI->SetRadio(FALSE);
}
void CCY457OpenGLView::OnQuadricDisk()
{//圓盤
m_Quadric = 3;
InvalidateRect(NULL,FALSE);
}
void CCY457OpenGLView::OnUpdateQuadricDisk(CCmdUI* pCmdUI)
{
if(m_Quadric == 3)
pCmdUI->SetRadio(TRUE);
else
pCmdUI->SetRadio(FALSE);
}
void CCY457OpenGLView::OnQuadricPartialdisk()
{////半圓盤
m_Quadric = 4;
InvalidateRect(NULL,FALSE);
}
void CCY457OpenGLView::OnUpdateQuadricPartialdisk(CCmdUI* pCmdUI)
{
if(m_Quadric == 4)
pCmdUI->SetRadio(TRUE);
else
pCmdUI->SetRadio(FALSE);
}
3,繪制函數修改如下：
void CCY457OpenGLView::RenderScene ()
{//繪制函數
glTranslatef(0.0f,0.0f,-5.0f);
glRotatef(m_xRot,1.0f,0.0f,0.0f);
glRotatef(m_yRot,0.0f,1.0f,0.0f);
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D,m_Texture[0]);
GLUquadricObj* obj;
obj = gluNewQuadric();
gluQuadricNormals(obj, GLU_SMOOTH);
gluQuadricTexture(obj, GL_TRUE);
switch(m_Quadric)
{
case 0: gluSphere(obj, 1, 20, 20);
break;
case 1: gluCylinder(obj, 1, 1, 3, 20, 20);
break;
case 2: gluCylinder(obj, 0.1, 1, 3, 20, 20);
break;
case 3: gluDisk(obj, 0.5, 1, 20, 20);
break;
case 4: gluPartialDisk(obj, 0.5, 1, 20, 20, 10, 180);
break;
}
glDisable(GL_TEXTURE_2D);
}
原文鏈接：
http://www.cnblogs.com/phinecos/archive/2008/11/06/1328269.html