我正在尝试学习在Qt中编写OpenGL代码。我创建了一个应用程序,显示两个图形。其中一个是三角形"A",另一个三角形"B"与"A"完全相同,只是绕z轴(z轴垂直于计算机屏幕)旋转了-90度。现在的问题是旋转会改变尺寸。我在下面发布了"main.cpp"的内容。
#include <QApplication>
#include <QHBoxLayout>
#include <QMessageBox>
#include <QtOpenGL/QGLWidget>
#include <QWidget>
class MyOpenGL:public QGLWidget
{
public:
MyOpenGL(QWidget * parent);
~MyOpenGL();
void initializeGL();
void resizeGL(int w, int h);
void paintGL();
};
MyOpenGL::MyOpenGL(QWidget *parent):QGLWidget(QGLFormat(QGL::SampleBuffers),parent)
{
setAutoFillBackground(false);
}
MyOpenGL::~MyOpenGL()
{
}
void MyOpenGL::initializeGL()
{
glShadeModel(GL_SMOOTH);
glClearColor(0.0f,0.0f,0.0f,0.0f);
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST);
}
void MyOpenGL::resizeGL(int w, int h)
{
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0f,width()/height(),10.0f,100.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
void MyOpenGL::paintGL()
{
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
//glTranslatef(0.0,0.0,-10.0);
glBegin(GL_TRIANGLES);
glColor3f(1.0f,0.0f,0.0f);
glVertex3f(-1.0f,0.0f,-10.0f);
glColor3f(0.0f,1.0f,0.0f);
glVertex3f(1.0f,0.0f,-10.0f);
glColor3f(0.0f,0.0f,1.0f);
glVertex3f(0.0f,4.0f,-10.0f);
glEnd();
glRotatef(90.0,0.0f,0.0f,-1.0f);
glBegin(GL_TRIANGLES);
glColor3f(1.0f,0.0f,0.0f);
glVertex3f(-1.0f,0.0f,-10.0f);
glColor3f(0.0f,1.0f,0.0f);
glVertex3f(1.0f,0.0f,-10.0f);
glColor3f(0.0f,0.0f,1.0f);
glVertex3f(0.0f,4.0f,-10.0f);
glEnd();
glLoadIdentity();
}
int main(int argc,char * argv[])
{
QApplication app(argc,argv);
MyOpenGL * f = new MyOpenGL(NULL);
f->show();
return app.exec();
}
这是个配置文件。
SOURCES += \
main.cpp
QT += opengl
这是生成应用程序的截图
据我所知,旋转不会改变尺寸。但是这里尺寸正在改变。如果有人能解决我的疑惑,我将非常感激他/她。