Qt_OpenGL：3D空間中移動映像

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Qt_OpenGL：3D空間中移動映像

//.h

#ifndef GLWIDGET_H#define GLWIDGET_H#include <QGLWidget>#include <QtOpenGL>class QGLWidget;class QTimer;typedef struct Stars{public:    int r, g, b;    GLfloat dist, angle;}Stars;class GLWidget : public QGLWidget{    Q_OBJECTpublic:    GLWidget(QWidget *parent = 0);    ~GLWidget();protected:    void initializeGL();    void paintGL();    void resizeGL(int w, int h);    void keyPressEvent(QKeyEvent*);    void timerEvent(QTimerEvent*);private:    bool fullscreen;    GLfloat rotate_angle;    GLfloat zoom;    GLfloat title;    GLfloat spin;    GLuint loop;    bool twinkle;    GLfloat blend;private:    void loadTextures();    GLuint texture[1];};#endif // GLWIDGET_H

//.cpp

#include "glwidget.h"#include <glut.h>#include <QtGui>#include <QtCore>//好吧我承認全部變數不好GLfloat light_ambient[4] = {0.5,0.5,0.5,1.0};GLfloat light_diffiuse[4] = {1.0,1.0,1.0,1.0};GLfloat light_position[4] = {0.0,0.0,2.0,0.0};static const int num = 50;static Stars stars[num];GLWidget::GLWidget(QWidget *parent)    : QGLWidget(parent){    fullscreen = false;    rotate_angle = 0.0;    zoom = -15.0;    title = 90.0;    spin = 0.1;    loop = 0;    twinkle = false;    blend = false;    startTimer(5);}void GLWidget::initializeGL(){    setGeometry(300,150,500,500);    loadTextures();    glEnable(GL_TEXTURE_2D);    glShadeModel(GL_SMOOTH);    glClearColor(0.0, 0.0, 0.0, 0.5);    glClearDepth(1.0);    glEnable(GL_DEPTH_TEST);    glDepthFunc(GL_LEQUAL);    glHint(GL_PERSPECTIVE_CORRECTION_HINT,GL_NICEST);    glBlendFunc(GL_SRC_ALPHA,GL_ONE);    glEnable(GL_BLEND);    //為num個星星對象賦初值    for(loop = 0; loop < num; ++loop){        stars[loop].angle = 0.0;        stars[loop].dist = (float(loop)/num) * 5.0;        stars[loop].r = rand() % 256;        stars[loop].g = rand() % 256;        stars[loop].b = rand() % 256;    }}void GLWidget::paintGL(){    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);    glBindTexture(GL_TEXTURE_2D, texture[0]);    for(loop = 0; loop < num; ++loop){        glLoadIdentity();        glTranslatef(0.0, 0.0, zoom);  //移向螢幕裡面        glRotatef(title, 1.0, 0.0, 0.0);  //沿x軸旋轉title        glRotatef(stars[loop].angle, 0.0, 1.0, 0.0); //每個星星沿y軸旋轉自己的角度        glTranslatef(stars[loop].dist, 0.0, 0.0);  //平移        glRotatef(-stars[loop].angle, 0.0, 1.0, 0.0);  //沿y軸反轉        glRotatef(-title, 1.0, 0.0, 0.0);    //沿x軸反轉        if(twinkle){     //如果星星閃爍            glColor4ub(stars[num-loop-1].r, stars[num-loop-1].g,                    stars[num-loop-1].b, 255);            glBegin(GL_QUADS);                glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,-1.0f, 0.0f);                glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,-1.0f, 0.0f);                glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 0.0f);                glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.0f);            glEnd();        }        //如果星星不閃爍        glRotatef(spin, 0.0f, 0.0f, 1.0f); //沿z軸自轉spin        glColor4ub(stars[loop].r, stars[loop].g, stars[loop].b, 255);        glBegin(GL_QUADS);            glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,-1.0f, 0.0f);            glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,-1.0f, 0.0f);            glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 0.0f);            glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.0f);        glEnd();        spin += 0.01f;        stars[loop].angle += float(loop)/num;        stars[loop].dist -= 0.01f; //距離逐漸減小，即越來越靠近螢幕        if(stars[loop].dist < 0){            stars[loop].dist += 5.0f;            stars[loop].r = rand() % 256;            stars[loop].g = rand() % 256;            stars[loop].b = rand() % 256;        }    }}void GLWidget::resizeGL(int w, int h){    if( 0 == h){        h = 1;    }    glViewport(0, 0, (GLsizei)w, (GLsizei)h);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    gluPerspective(45.0, (GLdouble)w/(GLdouble)h, 0.1, 100.0);    glColor4f(1.0f, 1.0f, 1.0f, 0.5f);    glBlendFunc(GL_SRC_ALPHA, GL_ONE);    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();}void GLWidget::keyPressEvent(QKeyEvent *event){    switch(event->key()){        case Qt::Key_T:{            twinkle = !twinkle;            updateGL();            break;        }        case Qt::Key_B:{            blend = !blend;            if(blend){                glEnable(GL_BLEND);                glDisable(GL_DEPTH_TEST);            }else{                glDisable(GL_BLEND);                glEnable(GL_DEPTH_TEST); //色彩混合和深度緩衝不能同時開啟            }            updateGL();            break;        }        case Qt::Key_PageUp:{      //移向螢幕            zoom -= 0.2;            updateGL();            break;        }        case Qt::Key_PageDown:{   //移向螢幕外            zoom += 0.2;            updateGL();            break;        }        case Qt::Key_Up:{          //加快旋轉速度            title += 0.5;            updateGL();            break;        }        case Qt::Key_Down:{            title -= 0.5;            updateGL();            break;        }        case Qt::Key_F1:{            fullscreen = !fullscreen;            if(fullscreen){                showFullScreen();            }else{                setGeometry(300,150,500,500);                showNormal();            }            updateGL();            break;        }        case Qt::Key_Escape:{            close();        }    }}void GLWidget::loadTextures(){    QImage tex, buf;    if(!buf.load(":Star.bmp")){        qWarning("Cannot open the image...");        QImage dummy(128, 128, QImage::Format_RGB32);        dummy.fill(Qt::green);        buf = dummy;    }    tex = convertToGLFormat(buf);    glGenTextures(1, &texture[0]);    glBindTexture(GL_TEXTURE_2D, texture[0]);    glTexImage2D(GL_TEXTURE_2D, 0, 3, tex.width(), tex.height(), 0, GL_RGBA,                 GL_UNSIGNED_BYTE, tex.bits());    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);}void GLWidget::timerEvent(QTimerEvent *){    updateGL();}GLWidget::~GLWidget(){}

//main.cpp

#include "glwidget.h"#include <QApplication>int main(int argc, char *argv[]){    QApplication a(argc, argv);    GLWidget w;    w.show();    return a.exec();}

//運行結果：

Qt_OpenGL：3D空間中移動映像