c++ - 在 Qt 中包含 OpenGL 库

Question

我在 QT 项目中使用 OpenGL。我现在正在尝试最基本的例子。 http://programanddesign.com/cpp/qt-opengl-code-example/

GLWidget.hpp

#ifndef _GLWIDGET_H
#define _GLWIDGET_H

#include <QtOpenGL/QGLWidget>

class GLWidget : public QGLWidget {

    Q_OBJECT // must include this if you use Qt signals/slots

public:
    GLWidget(QWidget *parent = NULL);

protected:
    void initializeGL();
    void resizeGL(int w, int h);
    void paintGL();
    void mousePressEvent(QMouseEvent *event);
    void mouseMoveEvent(QMouseEvent *event);
    void keyPressEvent(QKeyEvent *event);
};

#endif  /* _GLWIDGET_H */

GLWidget.cpp

#include <QtGui/QMouseEvent>
#include "GLWidget.h"

GLWidget::GLWidget(QWidget *parent) : QGLWidget(parent) {
    setMouseTracking(true);
}

void GLWidget::initializeGL() {
    glDisable(GL_TEXTURE_2D);
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_COLOR_MATERIAL);
    glEnable(GL_BLEND);
    glEnable(GL_POLYGON_SMOOTH);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glClearColor(0, 0, 0, 0);
}

void GLWidget::resizeGL(int w, int h) {
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluOrtho2D(0, w, 0, h); // set origin to bottom left corner
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}

void GLWidget::paintGL() {
    glClear(GL_COLOR_BUFFER_BIT);
    glColor3f(1,0,0);
    glBegin(GL_POLYGON);
    glVertex2f(0,0);
    glVertex2f(100,500);
    glVertex2f(500,100);
    glEnd();
}

void GLWidget::mousePressEvent(QMouseEvent *event) {

}
void GLWidget::mouseMoveEvent(QMouseEvent *event) {
    printf("%d, %d\n", event->x(), event->y());
}

void GLWidget::keyPressEvent(QKeyEvent* event) {
    switch(event->key()) {
    case Qt::Key_Escape:
        close();
        break;
    default:
        event->ignore();
        break;
    }
}

但是GL_COLOR_MATERIAL，GL_POLYGON_SMOOTH，glColor3f，glBegin，GL_POLYGON，glVertex2f，glEnd无法识别。有人可以告诉我如何解决这个问题吗？

Answer 1

您需要按如下方式添加 Qt OpenGL 头文件:

#include <QtOpenGL>

根据您使用的 OpenGL 函数，您可能还需要让 GLWidget 类继承自 QGLFunctions:http://qt-project.org/doc/qt-4.8/qglfunctions.html .