#include "openglwidget.h"
OpenglWidget::OpenglWidget(QWidget* parent)
:QGLWidget(parent),
m_rotateTriangle(0),
m_rotateRectangle(0)
{
initializeGL();
initWidget();
}
void OpenglWidget::initializeGL()
{
glShadeModel(GL_SMOOTH);
glClearColor(0.0, 0.0, 0.0, 0.0);
glClearDepth(1.0);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
}
void OpenglWidget::initWidget()
{
setGeometry( 400, 200, 640, 480 );
setWindowTitle(tr("opengl demo"));
}
void OpenglWidget::paintGL()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glTranslatef( -1.5, 0.0, -6.0 );
glRotatef( m_rotateRectangle, 0.0, 1.0, 0.0 );
glBegin( GL_QUADS );
glColor3f(1.0, 0.0, 0.0);
glVertex3f( -1.0, 1.0, 0.0 );
glColor3f(0.0, 1.0, 0.0);
glVertex3f( 1.0, 1.0, 0.0 );
glColor3f(0.0, 0.0, 1.0);
glVertex3f( 1.0, -1.0, 0.0 );
glColor3f(1.0, 1.0, 1.0);
glVertex3f( -1.0, -1.0, 0.0 );
glEnd();
glLoadIdentity();
glTranslatef( 1.5, 0.0, -6.0 );
glRotatef( m_rotateTriangle, 1.0, 0.0, 0.0 );
glColor3f((GLfloat)0.3, (GLfloat)0.2, (GLfloat)0.5);
glBegin( GL_TRIANGLES );
qDebug() << "this is a paintGL test!";
glVertex3f( 0.0, 1.0, 0.0 );
glVertex3f( -1.0, -1.0, 0.0 );
glVertex3f( 1.0, -1.0, 0.0 );
glEnd();
m_rotateRectangle += 20;
m_rotateTriangle += 20;
}
void OpenglWidget::resizeGL(int width, int height)
{
if(0 == height) {
height = 1;
}
glViewport(0, 0, (GLint)width, (GLint)height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
// gluPerspective(45.0, (GLfloat)width/(GLfloat)height, 0.1, 100.0);
GLdouble aspectRatio = (GLfloat)width/(GLfloat)height;
GLdouble zNear = 0.1;
GLdouble zFar = 100.0;
GLdouble rFov = 45.0 * 3.14159265 / 180.0;
glFrustum( -zNear * tan( rFov / 2.0 ) * aspectRatio,
zNear * tan( rFov / 2.0 ) * aspectRatio,
-zNear * tan( rFov / 2.0 ),
zNear * tan( rFov / 2.0 ),
zNear, zFar );
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
