如何在y或x轴上绘制圆柱体opengl

Question

我只想在opengl中绘制圆柱体。我发现了很多样品，但是他们都在z轴上绘制柱面。我希望他们在x或y轴。我怎样才能做到这一点。下面的代码是代码绘制缸Z方向，我不希望它

GLUquadricObj *quadratic; 
    quadratic = gluNewQuadric(); 
    gluCylinder(quadratic,0.1f,0.1f,3.0f,32,32); 

Answer 1

您可以使用glRotate(angle, x, y, z)旋转你的坐标系：

GLUquadricObj *quadratic; 
quadratic = gluNewQuadric(); 
glRotatef(90.0f, 0.0f, 1.0f, 0.0f); 
gluCylinder(quadratic,0.1f,0.1f,3.0f,32,32); 

http://www.opengl.org/sdk/docs/man/xhtml/glRotate.xml

Answer 2

在每一个渲染使用glPushMatrixglRotatef画缸，并与glPopMatrix完成绘图。

例：glRotatef(yRotationAngle, 0.0f, 1.0f, 0.0f); // Rotate your object around the y axis on yRotationAngle radians

例：OnRender()功能例如

void OnRender() { 
    glClearColor(1.0f, 0.0f, 0.0f, 1.0f); // Clear the background 
    glClear(GL_COLOR_BUFFER_BIT); //Clear the colour buffer 
    glLoadIdentity(); // Load the Identity Matrix to reset our drawing locations 

    glRotatef(yRotationAngle, 0.0f, 1.0f, 0.0f); // Rotate our object around the y axis on yRotationAngle radians 

    // here *render* your cylinder (create and delete it in the other place. Not while rendering) 
    gluCylinder(quadratic,0.1f,0.1f,3.0f,32,32); 

    glFlush(); // Flush the OpenGL buffers to the window 
}