main.cpp
1 #include <QApplication> 2 #include <iostream> 3 4 #include "teapots.h" 5 6 int main(int argc, char *argv[]) 7 { 8 QApplication app(argc, argv); 9 10 if (!QGLFormat::hasOpenGL()) { 11 std::cerr << "This system has no OpenGL support" << std::endl; 12 return 1; 13 } 14 15 if (!QGLFramebufferObject::hasOpenGLFramebufferObjects()) { 16 std::cerr << "This system has no framebuffer object support" 17 << std::endl; 18 return 1; 19 } 20 21 Teapots teapots; 22 teapots.setWindowTitle(QObject::tr("Teapots")); 23 teapots.resize(400, 400); 24 teapots.show(); 25 26 return app.exec(); 27 }
teapots.h
#ifndef TEAPOTS_H #define TEAPOTS_H #include <QGLFramebufferObject> #include <QGLWidget> class Teapots : public QGLWidget { Q_OBJECT public: Teapots(QWidget *parent = 0); ~Teapots(); protected: //实现了OpenGL的高级处理函数: void initializeGL(); void resizeGL(int width, int height); void paintGL(); //以便用户绘制一个橡皮筋选择框 void mousePressEvent(QMouseEvent *event); void mouseMoveEvent(QMouseEvent *event); void mouseReleaseEvent(QMouseEvent *event); //私有函数负责创建茶壶对象以及茶壶的绘制. private: void createGLTeapotObject(); void drawTeapot(GLfloat x, GLfloat y, GLfloat ambientR, GLfloat ambientG, GLfloat ambientB, GLfloat diffuseR, GLfloat diffuseG, GLfloat diffuseB, GLfloat specularR, GLfloat specularG, GLfloat specularB, GLfloat shininess); void drawTeapots(); //私有变量可以保存framebuffer对象,茶壶对象 QGLFramebufferObject *fbObject; GLuint glTeapotObject; //橡皮筋选择框的各个角 QPoint rubberBandCorner1; QPoint rubberBandCorner2; //橡皮筋框的可见属性 bool rubberBandIsShown; }; #endif
teapots.cpp
#include <QtGui> #include <QtOpenGL> #include "teapots.h" Teapots::Teapots(QWidget *parent) : QGLWidget(parent) { //初始化rubberBandIsShown私有变量 rubberBandIsShown = false; makeCurrent(); //创建framebuffer对象 fbObject = new QGLFramebufferObject(1024, 1024, QGLFramebufferObject::Depth); //创建茶壶对象 createGLTeapotObject(); } //释放与framebuffer对象和茶壶相关的资源 Teapots::~Teapots() { makeCurrent(); delete fbObject; glDeleteLists(glTeapotObject, 1); } //设置光照模式,打开OpenGL特性 void Teapots::initializeGL() { static const GLfloat ambient[] = { 0.0, 0.0, 0.0, 1.0 }; static const GLfloat diffuse[] = { 1.0, 1.0, 1.0, 1.0 }; static const GLfloat position[] = { 0.0, 3.0, 3.0, 0.0 }; static const GLfloat lmodelAmbient[] = { 0.2, 0.2, 0.2, 1.0 }; static const GLfloat localView[] = { 0.0 }; glLightfv(GL_LIGHT0, GL_AMBIENT, ambient); glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse); glLightfv(GL_LIGHT0, GL_POSITION, position); glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodelAmbient); glLightModelfv(GL_LIGHT_MODEL_LOCAL_VIEWER, localView); glFrontFace(GL_CW); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glEnable(GL_AUTO_NORMAL); glEnable(GL_NORMALIZE); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LESS); } //在Teapot窗口改变大小时重绘茶壶场景. void Teapots::resizeGL(int width, int height) { //为了在framebuffer对象上绘制茶壶 fbObject->bind(); //设置一些OpenGL特性,以及投影和模式视图矩阵 glDisable(GL_TEXTURE_2D); glEnable(GL_LIGHTING); glEnable(GL_DEPTH_TEST); glViewport(0, 0, width, height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); if (width <= height) { glOrtho(0.0, 20.0, 0.0, 20.0 * GLfloat(height) / GLfloat(width), -10.0, 10.0); } else { glOrtho(0.0, 20.0 * GLfloat(width) / GLfloat(height), 0.0, 20.0, -10.0, 10.0); } glMatrixMode(GL_MODELVIEW); //在framebuffer对象上绘制茶壶 drawTeapots(); //释放framebuffer对象,确保随后的OpenGL绘制操作不会发生 //在framebuffer对象上 fbObject->release(); } //先重新设置投影和模式视图矩阵 //然后把framebuffer对象绑定到纹理上,绘制一个带有该纹理的矩形覆盖 //整个窗口部件 void Teapots::paintGL() { glDisable(GL_LIGHTING); glViewport(0, 0, width(), height()); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glDisable(GL_DEPTH_TEST); glClear(GL_COLOR_BUFFER_BIT); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, fbObject->texture()); glColor3f(1.0, 1.0, 1.0); GLfloat s = width() / GLfloat(fbObject->size().width()); GLfloat t = height() / GLfloat(fbObject->size().height()); glBegin(GL_QUADS); glTexCoord2f(0.0, 0.0); glVertex2f(-1.0, -1.0); glTexCoord2f(s, 0.0); glVertex2f(1.0, -1.0); glTexCoord2f(s, t); glVertex2f(1.0, 1.0); glTexCoord2f(0.0, t); glVertex2f(-1.0, 1.0); glEnd(); //如果橡皮筋框是可见的,我们可以把它绘制在矩形 上 if (rubberBandIsShown) { glMatrixMode(GL_PROJECTION); glOrtho(0, width(), height(), 0, 0, 100); glMatrixMode(GL_MODELVIEW); glDisable(GL_TEXTURE_2D); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glLineWidth(4.0); glColor4f(1.0, 1.0, 1.0, 0.2); glRecti(rubberBandCorner1.x(), rubberBandCorner1.y(), rubberBandCorner2.x(), rubberBandCorner2.y()); glColor4f(1.0, 1.0, 0.0, 0.5); glLineStipple(3, 0xAAAA); glEnable(GL_LINE_STIPPLE); glBegin(GL_LINE_LOOP); glVertex2i(rubberBandCorner1.x(), rubberBandCorner1.y()); glVertex2i(rubberBandCorner2.x(), rubberBandCorner1.y()); glVertex2i(rubberBandCorner2.x(), rubberBandCorner2.y()); glVertex2i(rubberBandCorner1.x(), rubberBandCorner2.y()); glEnd(); glLineWidth(1.0); glDisable(GL_LINE_STIPPLE); glDisable(GL_BLEND); } } //鼠标事件处理器负责更新用来绘制橡皮筋框的rubberBandCorner1, //rubberBandCorner2和rubberBandIsShown变量,并且调用updateGL() //重绘场景.绘制场景的速度很快,因为paintGL()仅绘制一个纹理矩形 //以及其上的橡皮筋选择框.只有当用户改变窗口大小时,场景才在 //resizeGL()中重新绘制 void Teapots::mousePressEvent(QMouseEvent *event) { rubberBandCorner1 = event->pos(); rubberBandCorner2 = event->pos(); rubberBandIsShown = true; } void Teapots::mouseMoveEvent(QMouseEvent *event) { if (rubberBandIsShown) { rubberBandCorner2 = event->pos(); updateGL(); } } void Teapots::mouseReleaseEvent(QMouseEvent * /* event */) { if (rubberBandIsShown) { rubberBandIsShown = false; updateGL(); } } void Teapots::createGLTeapotObject() { static const int patch[][16] = { { 102, 103, 104, 105, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, { 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27 }, { 24, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 }, { 96, 96, 96, 96, 97, 98, 99, 100, 101, 101, 101, 101, 0, 1, 2, 3 }, { 0, 1, 2, 3, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117 }, { 118, 118, 118, 118, 124, 122, 119, 121, 123, 126, 125, 120, 40, 39, 38, 37 }, { 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56 }, { 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 28, 65, 66, 67 }, { 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83 }, { 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 } }; static const GLfloat cp[][3] = { { 0.2, 0, 2.7 }, { 0.2, -0.112, 2.7 }, { 0.112, -0.2, 2.7 }, { 0, -0.2, 2.7 }, { 1.3375, 0, 2.53125 }, { 1.3375, -0.749, 2.53125 }, { 0.749, -1.3375, 2.53125 }, { 0, -1.3375, 2.53125 }, { 1.4375, 0, 2.53125 }, { 1.4375, -0.805, 2.53125 }, { 0.805, -1.4375, 2.53125 }, { 0, -1.4375, 2.53125 }, { 1.5, 0, 2.4 }, { 1.5, -0.84, 2.4 }, { 0.84, -1.5, 2.4 }, { 0, -1.5, 2.4 }, { 1.75, 0, 1.875 }, { 1.75, -0.98, 1.875 }, { 0.98, -1.75, 1.875 }, { 0, -1.75, 1.875 }, { 2, 0, 1.35 }, { 2, -1.12, 1.35 }, { 1.12, -2, 1.35 }, { 0, -2, 1.35 }, { 2, 0, 0.9 }, { 2, -1.12, 0.9 }, { 1.12, -2, 0.9 }, { 0, -2, 0.9 }, { -2, 0, 0.9 }, { 2, 0, 0.45 }, { 2, -1.12, 0.45 }, { 1.12, -2, 0.45 }, { 0, -2, 0.45 }, { 1.5, 0, 0.225 }, { 1.5, -0.84, 0.225 }, { 0.84, -1.5, 0.225 }, { 0, -1.5, 0.225 }, { 1.5, 0, 0.15 }, { 1.5, -0.84, 0.15 }, { 0.84, -1.5, 0.15 }, { 0, -1.5, 0.15 }, { -1.6, 0, 2.025 }, { -1.6, -0.3, 2.025 }, { -1.5, -0.3, 2.25 }, { -1.5, 0, 2.25 }, { -2.3, 0, 2.025 }, { -2.3, -0.3, 2.025 }, { -2.5, -0.3, 2.25 }, { -2.5, 0, 2.25 }, { -2.7, 0, 2.025 }, { -2.7, -0.3, 2.025 }, { -3, -0.3, 2.25 }, { -3, 0, 2.25 }, { -2.7, 0, 1.8 }, { -2.7, -0.3, 1.8 }, { -3, -0.3, 1.8 }, { -3, 0, 1.8 }, { -2.7, 0, 1.575 }, { -2.7, -0.3, 1.575 }, { -3, -0.3, 1.35 }, { -3, 0, 1.35 }, { -2.5, 0, 1.125 }, { -2.5, -0.3, 1.125 }, { -2.65, -0.3, 0.9375 }, { -2.65, 0, 0.9375 }, { -2, -0.3, 0.9 }, { -1.9, -0.3, 0.6 }, { -1.9, 0, 0.6 }, { 1.7, 0, 1.425 }, { 1.7, -0.66, 1.425 }, { 1.7, -0.66, 0.6 }, { 1.7, 0, 0.6 }, { 2.6, 0, 1.425 }, { 2.6, -0.66, 1.425 }, { 3.1, -0.66, 0.825 }, { 3.1, 0, 0.825 }, { 2.3, 0, 2.1 }, { 2.3, -0.25, 2.1 }, { 2.4, -0.25, 2.025 }, { 2.4, 0, 2.025 }, { 2.7, 0, 2.4 }, { 2.7, -0.25, 2.4 }, { 3.3, -0.25, 2.4 }, { 3.3, 0, 2.4 }, { 2.8, 0, 2.475 }, { 2.8, -0.25, 2.475 }, { 3.525, -0.25, 2.49375 }, { 3.525, 0, 2.49375 }, { 2.9, 0, 2.475 }, { 2.9, -0.15, 2.475 }, { 3.45, -0.15, 2.5125 }, { 3.45, 0, 2.5125 }, { 2.8, 0, 2.4 }, { 2.8, -0.15, 2.4 }, { 3.2, -0.15, 2.4 }, { 3.2, 0, 2.4 }, { 0, 0, 3.15 }, { 0.8, 0, 3.15 }, { 0.8, -0.45, 3.15 }, { 0.45, -0.8, 3.15 }, { 0, -0.8, 3.15 }, { 0, 0, 2.85 }, { 1.4, 0, 2.4 }, { 1.4, -0.784, 2.4 }, { 0.784, -1.4, 2.4 }, { 0, -1.4, 2.4 }, { 0.4, 0, 2.55 }, { 0.4, -0.224, 2.55 }, { 0.224, -0.4, 2.55 }, { 0, -0.4, 2.55 }, { 1.3, 0, 2.55 }, { 1.3, -0.728, 2.55 }, { 0.728, -1.3, 2.55 }, { 0, -1.3, 2.55 }, { 1.3, 0, 2.4 }, { 1.3, -0.728, 2.4 }, { 0.728, -1.3, 2.4 }, { 0, -1.3, 2.4 }, { 0, 0, 0 }, { 1.425, -0.798, 0 }, { 1.5, 0, 0.075 }, { 1.425, 0, 0 }, { 0.798, -1.425, 0 }, { 0, -1.5, 0.075 }, { 0, -1.425, 0 }, { 1.5, -0.84, 0.075 }, { 0.84, -1.5, 0.075 } }; static const GLfloat tex[2][2][2] = { { { 0, 0 }, { 1, 0 } }, { { 0, 1 }, { 1, 1 } } }; GLfloat p[4][4][3]; GLfloat q[4][4][3]; GLfloat r[4][4][3]; GLfloat s[4][4][3]; int grid = 14; makeCurrent(); glTeapotObject = glGenLists(1); glNewList(glTeapotObject, GL_COMPILE); glPushMatrix(); glRotatef(270.0, 1.0, 0.0, 0.0); glScalef(0.5, 0.5, 0.5); glTranslatef(0.0, 0.0, -1.5); for (int i = 0; i < 10; i++) { for (int j = 0; j < 4; j++) { for (int k = 0; k < 4; k++) { for (int l = 0; l < 3; l++) { p[j][k][l] = cp[patch[i][(j * 4) + k]][l]; q[j][k][l] = cp[patch[i][(j * 4) + (3 - k)]][l]; if (l == 1) q[j][k][l] *= -1.0; if (i < 6) { r[j][k][l] = cp[patch[i][(j * 4) + (3 - k)]][l]; if (l == 0) r[j][k][l] *= -1.0; s[j][k][l] = cp[patch[i][(j * 4) + k]][l]; if (l <= 1) s[j][k][l] *= -1.0; } } } } glMap2f(GL_MAP2_TEXTURE_COORD_2, 0, 1, 2, 2, 0, 1, 4, 2, &tex[0][0][0]); glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, &p[0][0][0]); glEnable(GL_MAP2_VERTEX_3); glEnable(GL_MAP2_TEXTURE_COORD_2); glMapGrid2f(grid, 0.0, 1.0, grid, 0.0, 1.0); glEvalMesh2(GL_LINE, 0, grid, 0, grid); glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, &q[0][0][0]); glEvalMesh2(GL_LINE, 0, grid, 0, grid); if (i < 6) { glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, &r[0][0][0]); glEvalMesh2(GL_LINE, 0, grid, 0, grid); glMap2f(GL_MAP2_VERTEX_3, 0, 1, 3, 4, 0, 1, 12, 4, &s[0][0][0]); glEvalMesh2(GL_LINE, 0, grid, 0, grid); } } glDisable(GL_MAP2_VERTEX_3); glDisable(GL_MAP2_TEXTURE_COORD_2); glPopMatrix(); glEndList(); } void Teapots::drawTeapot(GLfloat x, GLfloat y, GLfloat ambientR, GLfloat ambientG, GLfloat ambientB, GLfloat diffuseR, GLfloat diffuseG, GLfloat diffuseB, GLfloat specularR, GLfloat specularG, GLfloat specularB, GLfloat shininess) { GLfloat matrix[4]; matrix[3] = 1.0; glPushMatrix(); glTranslatef(x, y, 0.0); matrix[0] = ambientR; matrix[1] = ambientG; matrix[2] = ambientB; glMaterialfv(GL_FRONT, GL_AMBIENT, matrix); matrix[0] = diffuseR; matrix[1] = diffuseG; matrix[2] = diffuseB; glMaterialfv(GL_FRONT, GL_DIFFUSE, matrix); matrix[0] = specularR; matrix[1] = specularG; matrix[2] = specularB; glMaterialfv(GL_FRONT, GL_SPECULAR, matrix); glMaterialf(GL_FRONT, GL_SHININESS, shininess * 128.0); glCallList(glTeapotObject); glPopMatrix(); } void Teapots::drawTeapots() { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); drawTeapot(2.0, 17.0, 0.0215, 0.1745, 0.0215, 0.07568, 0.61424, 0.07568, 0.633, 0.727811, 0.633, 0.6); drawTeapot(2.0, 14.0, 0.135, 0.2225, 0.1575, 0.54, 0.89, 0.63, 0.316228, 0.316228, 0.316228, 0.1); drawTeapot(2.0, 11.0, 0.05375, 0.05, 0.06625, 0.18275, 0.17, 0.22525, 0.332741, 0.328634, 0.346435, 0.3); drawTeapot(2.0, 8.0, 0.25, 0.20725, 0.20725, 1, 0.829, 0.829, 0.296648, 0.296648, 0.296648, 0.088); drawTeapot(2.0, 5.0, 0.1745, 0.01175, 0.01175, 0.61424, 0.04136, 0.04136, 0.727811, 0.626959, 0.626959, 0.6); drawTeapot(2.0, 2.0, 0.1, 0.18725, 0.1745, 0.396, 0.74151, 0.69102, 0.297254, 0.30829, 0.306678, 0.1); drawTeapot(6.0, 17.0, 0.329412, 0.223529, 0.027451, 0.780392, 0.568627, 0.113725, 0.992157, 0.941176, 0.807843, 0.21794872); drawTeapot(6.0, 14.0, 0.2125, 0.1275, 0.054, 0.714, 0.4284, 0.18144, 0.393548, 0.271906, 0.166721, 0.2); drawTeapot(6.0, 11.0, 0.25, 0.25, 0.25, 0.4, 0.4, 0.4, 0.774597, 0.774597, 0.774597, 0.6); drawTeapot(6.0, 8.0, 0.19125, 0.0735, 0.0225, 0.7038, 0.27048, 0.0828, 0.256777, 0.137622, 0.086014, 0.1); drawTeapot(6.0, 5.0, 0.24725, 0.1995, 0.0745, 0.75164, 0.60648, 0.22648, 0.628281, 0.555802, 0.366065, 0.4); drawTeapot(6.0, 2.0, 0.19225, 0.19225, 0.19225, 0.50754, 0.50754, 0.50754, 0.508273, 0.508273, 0.508273, 0.4); drawTeapot(10.0, 17.0, 0.0, 0.0, 0.0, 0.01, 0.01, 0.01, 0.50, 0.50, 0.50, 0.25); drawTeapot(10.0, 14.0, 0.0, 0.1, 0.06, 0.0, 0.50980392, 0.50980392, 0.50196078, 0.50196078, 0.50196078, 0.25); drawTeapot(10.0, 11.0, 0.0, 0.0, 0.0, 0.1, 0.35, 0.1, 0.45, 0.55, 0.45, 0.25); drawTeapot(10.0, 8.0, 0.0, 0.0, 0.0, 0.5, 0.0, 0.0, 0.7, 0.6, 0.6, 0.25); drawTeapot(10.0, 5.0, 0.0, 0.0, 0.0, 0.55, 0.55, 0.55, 0.70, 0.70, 0.70, 0.25); drawTeapot(10.0, 2.0, 0.0, 0.0, 0.0, 0.5, 0.5, 0.0, 0.60, 0.60, 0.50, 0.25); drawTeapot(14.0, 17.0, 0.02, 0.02, 0.02, 0.01, 0.01, 0.01, 0.4, 0.4, 0.4, 0.078125); drawTeapot(14.0, 14.0, 0.0, 0.05, 0.05, 0.4, 0.5, 0.5, 0.04, 0.7, 0.7, 0.078125); drawTeapot(14.0, 11.0, 0.0, 0.05, 0.0, 0.4, 0.5, 0.4, 0.04, 0.7, 0.04, 0.078125); drawTeapot(14.0, 8.0, 0.05, 0.0, 0.0, 0.5, 0.4, 0.4, 0.7, 0.04, 0.04, 0.078125); drawTeapot(14.0, 5.0, 0.05, 0.05, 0.05, 0.5, 0.5, 0.5, 0.7, 0.7, 0.7, 0.078125); drawTeapot(14.0, 2.0, 0.05, 0.05, 0.0, 0.5, 0.5, 0.4, 0.7, 0.7, 0.04, 0.078125); }