QOpenGLWidget第六篇(简化相机类)

本文介绍了如何在QOpenGLWidget中通过QMatrix类直接操作MVP矩阵,省去OpenGLCamera和投影转换,实现鼠标滚轮、平移和键盘控制的3D视图调整。删除了相机类并重构了事件处理,展示了更简洁的代码实现和控制方式。

1、在QOpenGLWidget 第五篇(相机空间)中我们实现了一个OpenGLMVP投影转换类以及OpenGLCamera相机类,在这里我们用另一个已有的QMatrix类来替代这两个投影变换以及相机空间类。

在QMatrix矩阵类中,已经存在接口perspective来设置透视投影和otho正射投影。而且还存在接口lookAt这个类来设置观察方向。

有了这三个接口,那我们就可以完全去掉投影转换以及相机空间。

改动地方:

1、在OpenGLWidget头文件中将 OpenGLCamera *m_pCamera; 替换为QMatrix4x4 m_mvpMatrix;

2、将OpenGLWidget源文件中第47行到第54行替换为 m_shaderProgram->setUniformValue("gWorld", m_mvpMatrix);

3、将OpenGLWidget类中的initOpenGLCamera方法删掉;

4、修改鼠标滚轮事件:

 
void OpenGLWidget::wheelEvent(QWheelEvent *ev)
{
	double val = ev->delta() * 1.0 / 40;
	m_mvpMatrix.translate(0, 0, val * 0.1);
	repaint(); QOpenGLWidget::wheelEvent(ev);
}

 5、修改鼠标平移事件:

void OpenGLWidget::mouseMoveEvent(QMouseEvent *ev)
{
	if(m_mouseStatus &= kMouseMove)
	{
		QPoint pt = ev->pos();
		double w = width(), h = height();
		double x = (pt.x() - m_lastPt.x()) / w;
		double y = (m_lastPt.y() - pt.y()) / h;
		m_mvpMatrix.translate(x, y, 0);
		m_lastPt = pt; repaint();
	}
	QOpenGLWidget::mouseMoveEvent(ev);
}

void OpenGLWidget::mousePressEvent(QMouseEvent *ev)
{
	if(ev->button() == Qt::MiddleButton)
	{
		m_mouseStatus |= kMouseMove;
		m_lastPt = ev->pos();
	}
	QOpenGLWidget::mousePressEvent(ev);
}

void OpenGLWidget::mouseReleaseEvent(QMouseEvent *ev)
{
	if(ev->button() == Qt::MiddleButton)
		m_mouseStatus ^= kMouseMove;
	QOpenGLWidget::mouseReleaseEvent(ev);
}

 6、修改键盘控制事件:

void OpenGLWidget::keyPressEvent(QKeyEvent *ev)
{
	QVector3D trans;
	switch(ev->key())
	{
		case Qt::Key_Up: trans = QVector3D(0, 1, 0); break;
		case Qt::Key_Down: trans = QVector3D(0, -1, 0); break;
		case Qt::Key_Left: trans = QVector3D(-1, 0, 0); break;
		case Qt::Key_Right: trans = QVector3D(1, 0, 0); break;
	}
	repaint();
	QOpenGLWidget::keyPressEvent(ev);
}

 7、最后在头文件中添加鼠标状态枚举并且添加成员变量MouseStatus m_mouseStatus = kMouseNone;

鼠标状态枚举:

enum MouseStatusFlag
{
	kMouseNone = 0,
	kMouseMove = 1,
	kMouseScale = 2
};

Q_DECLARE_FLAGS(MouseStatus, MouseStatusFlag)

 成员变量:

QPoint m_lastPt;
QMatrix4x4 m_mvpMatrix;
QOpenGLBuffer m_vbo, m_ebo;
QOpenGLVertexArrayObject m_vao;
QOpenGLShaderProgram *m_shaderProgram;
MouseStatus m_mouseStatus = kMouseNone;

 最终运行效果如下:

如果没有运行出来可以下载源码:源码下载地址

QOpenGLWidget 第五篇 相机空间

QOpenGLWidget 第七篇 vao、vbo随机绘制线

https://blog.youkuaiyun.com/Wang_Dou_Dou_/article/details/121065437 根据网页中的代码,使用qt中相关函数实现相同功能,在窗口中画出对应3D图像 class Point_Light { public: Point_Light() { this->update(); } void Draw(Shader &shader) { glBindVertexArray(light_VAO); glDrawArrays(GL_TRIANGLES, 0, 36); glBindVertexArray(0); } ~Point_Light() { glBindBuffer(GL_ARRAY_BUFFER, 0); glBindVertexArray(0); glDeleteVertexArrays(1, &light_VAO); glDeleteBuffers(1, &light_VBO); } private: GLuint light_VAO, light_VBO; void update() {GLfloat vertices_2[] = { // 坐标 // x、y、z 坐标 // color -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, -0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, -0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, -0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, 1.0f, -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, // 0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.5f, -0.5f, 0.5f, 1.0f, 1.0f, 0.0f, 0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 1.0f, 0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 1.0f, 0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 1.0f, 0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 1.0f, -0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 1.0f, -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 1.0f, -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 1.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 1.0f, -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 1.0f, -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 1.0f, }; glGenVertexArrays(1, &light_VAO); glGenBuffers(1, &light_VBO); glBindVertexArray(light_VAO); glBindBuffer(GL_ARRAY_BUFFER, light_VBO); glBufferData(GL_ARRAY_BUFFER, sizeof(vertices_2), vertices_2, GL_STATIC_DRAW); glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(GLfloat), (GLvoid*)0); glEnableVertexAttribArray(0); } }; 着色器:class Shader { private: GLuint vertex, fragment; public: GLuint Program; Shader(const GLchar *vertexPath, const GLchar *fragmentPath) { string vertexCode; string fragmentCode; ifstream vShaderFile; ifstream fShaderFile; vShaderFile.exceptions(ifstream::badbit); fShaderFile.exceptions(ifstream::badbit); try { vShaderFile.open(vertexPath); fShaderFile.open(fragmentPath); stringstream vShaderStream, fShaderStream; vShaderStream << vShaderFile.rdbuf(); fShaderStream << fShaderFile.rdbuf(); vShaderFile.close(); fShaderFile.close(); vertexCode = vShaderStream.str(); fragmentCode = fShaderStream.str(); } catch (ifstream::failure e) { cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ" << endl; } const GLchar *vShaderCode = vertexCode.c_str(); const GLchar *fShaderCode = fragmentCode.c_str(); vertex = glCreateShader(GL_VERTEX_SHADER); glShaderSource(vertex, 1, &vShaderCode, NULL); glCompileShader(vertex); GLint flag; GLchar infoLog[512]; glGetShaderiv(vertex, GL_COMPILE_STATUS, &flag); if (!flag) { glGetShaderInfoLog(vertex, 512, NULL, infoLog); cout << "ERROR::SHADER::VERTEX::COMPILATION_FAILED\n" << infoLog << endl; } fragment = glCreateShader(GL_FRAGMENT_SHADER); glShaderSource(fragment, 1, &fShaderCode, NULL); glCompileShader(fragment); glGetShaderiv(fragment, GL_COMPILE_STATUS, &flag); if (!flag) { glGetShaderInfoLog(fragment, 512, NULL, infoLog); cout << "ERROR::SHADER::FRAGMENT::COMPILATION_FAILED\n" << infoLog << endl; } this->Program = glCreateProgram(); glAttachShader(this->Program, vertex); glAttachShader(this->Program, fragment); glLinkProgram(this->Program); if (!flag) { glGetProgramInfoLog(this->Program, 512, NULL, infoLog); cout << "ERROR::SHADER::PROGRAM::LINKING_FAILED\n" << infoLog << endl; } glDeleteShader(vertex); glDeleteShader(fragment); } ~Shader() { glDetachShader(this->Program, vertex); glDetachShader(this->Program, fragment); glDeleteShader(vertex); glDeleteShader(fragment); glDeleteProgram(this->Program); } void Use() { glUseProgram(this->Program); } }; 观察相机:enum Camera_Movement { // 枚举型 FORWARD, // 向前 BACKWARD, // 向后 LEFT, // 向左 RIGHT, // 向右 UPWARD, // 向上 DOWNWARD // 向下 }; const GLfloat SPEED = 6.0f; // 初始速度 class Camera { public: // 构造函数 Camera(glm::vec3 position = glm::vec3(0.0f, 0.0f, 5.0f), glm::vec3 target = glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3 up = glm::vec3(0.0f, 1.0f, 0.0f)) :movementSpeed(SPEED) { this->position = position; this->camera_Z_axis = target; this->camera_Y_axis = up; this->camera_X_axis = glm::normalize(glm::cross(this->camera_Z_axis, this->camera_Y_axis)); this->updateCameraVectors(); // 实时更新 } // 观察矩阵 glm::mat4 GetViewMatrix() { return glm::lookAt(this->position, this->position + this->camera_Z_axis, this->camera_Y_axis); } void ProcessKeyboard(Camera_Movement direction, float deltaTime) { float velocity = this->movementSpeed * deltaTime; if (direction == FORWARD) this->position += this->camera_Z_axis * velocity; if (direction == BACKWARD) this->position -= this->camera_Z_axis * velocity; if (direction == LEFT) this->position -= this->camera_X_axis * velocity; if (direction == RIGHT) this->position += this->camera_X_axis * velocity; if (direction == UPWARD) this->position += this->camera_Y_axis * velocity; if (direction == DOWNWARD) this->position -= this->camera_Y_axis * velocity; } glm::vec3 GetPosition() // 下一篇文章使用 { return this->position; } private: // 摄影机的属性 glm::vec3 position; // 相机当前位置 glm::vec3 camera_Z_axis; // 摄影机的 Z 轴向量 glm::vec3 camera_X_axis; // 摄影机的 X 轴向量 glm::vec3 camera_Y_axis; // 摄影机的 Y 轴向量 GLfloat movementSpeed; // 镜头移动速度 void updateCameraVectors() { this->camera_Z_axis = glm::normalize(this->camera_Z_axis); this->camera_X_axis = glm::normalize(glm::cross(this->camera_Z_axis, this->camera_Y_axis)); this->camera_Y_axis = glm::normalize(glm::cross(this->camera_X_axis, this->camera_Z_axis)); } }; Shader ourShader = Shader("F:/test/OpenGLTest/shaders/shader_v.txt", "F:/test/OpenGLTest/shaders/shader_f.txt"); Shader lightShader = Shader("F:/test/OpenGLTest/shaders/light_v.txt", "F:/test/OpenGLTest/shaders/light_f.txt"); 可以使用qt相关方式修改自定义着色器,也可以使用QT相关函数替代相关功能,去除自定义着色器,只有相关功能可以实现,之前着色器时从文件中读取的,依旧需要保留从文件中读取,请给出实现后的完整代码以及详细的中文注释,头文件和源文件需要分开,不同在不同文件
07-30
https://blog.youkuaiyun.com/Wang_Dou_Dou_/article/details/121065437 根据网页中的代码,使用qt中相关函数实现相同功能,在窗口中画出对应3D图像 class Point_Light { public: Point_Light() { this->update(); } void Draw(Shader &shader) { glBindVertexArray(light_VAO); glDrawArrays(GL_TRIANGLES, 0, 36); glBindVertexArray(0); } ~Point_Light() { glBindBuffer(GL_ARRAY_BUFFER, 0); glBindVertexArray(0); glDeleteVertexArrays(1, &light_VAO); glDeleteBuffers(1, &light_VBO); } private: GLuint light_VAO, light_VBO; void update() {GLfloat vertices_2[] = { // 坐标 // x、y、z 坐标 // color -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, -0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, -0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, -0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, -0.5f, 0.5f, -0.5f, 0.0f, 0.0f, 1.0f, -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, -0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, -0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, // 0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.5f, -0.5f, 0.5f, 1.0f, 1.0f, 0.0f, 0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 1.0f, 0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 1.0f, 0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 1.0f, 0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 1.0f, -0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 1.0f, -0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 1.0f, -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 1.0f, 0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 1.0f, -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 1.0f, -0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 1.0f, }; glGenVertexArrays(1, &light_VAO); glGenBuffers(1, &light_VBO); glBindVertexArray(light_VAO); glBindBuffer(GL_ARRAY_BUFFER, light_VBO); glBufferData(GL_ARRAY_BUFFER, sizeof(vertices_2), vertices_2, GL_STATIC_DRAW); glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(GLfloat), (GLvoid*)0); glEnableVertexAttribArray(0); } }; 着色器:class Shader { private: GLuint vertex, fragment; public: GLuint Program; Shader(const GLchar *vertexPath, const GLchar *fragmentPath) { string vertexCode; string fragmentCode; ifstream vShaderFile; ifstream fShaderFile; vShaderFile.exceptions(ifstream::badbit); fShaderFile.exceptions(ifstream::badbit); try { vShaderFile.open(vertexPath); fShaderFile.open(fragmentPath); stringstream vShaderStream, fShaderStream; vShaderStream << vShaderFile.rdbuf(); fShaderStream << fShaderFile.rdbuf(); vShaderFile.close(); fShaderFile.close(); vertexCode = vShaderStream.str(); fragmentCode = fShaderStream.str(); } catch (ifstream::failure e) { cout << “ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ” << endl; } const GLchar *vShaderCode = vertexCode.c_str(); const GLchar *fShaderCode = fragmentCode.c_str(); vertex = glCreateShader(GL_VERTEX_SHADER); glShaderSource(vertex, 1, &vShaderCode, NULL); glCompileShader(vertex); GLint flag; GLchar infoLog[512]; glGetShaderiv(vertex, GL_COMPILE_STATUS, &flag); if (!flag) { glGetShaderInfoLog(vertex, 512, NULL, infoLog); cout << “ERROR::SHADER::VERTEX::COMPILATION_FAILED\n” << infoLog << endl; } fragment = glCreateShader(GL_FRAGMENT_SHADER); glShaderSource(fragment, 1, &fShaderCode, NULL); glCompileShader(fragment); glGetShaderiv(fragment, GL_COMPILE_STATUS, &flag); if (!flag) { glGetShaderInfoLog(fragment, 512, NULL, infoLog); cout << “ERROR::SHADER::FRAGMENT::COMPILATION_FAILED\n” << infoLog << endl; } this->Program = glCreateProgram(); glAttachShader(this->Program, vertex); glAttachShader(this->Program, fragment); glLinkProgram(this->Program); if (!flag) { glGetProgramInfoLog(this->Program, 512, NULL, infoLog); cout << “ERROR::SHADER::PROGRAM::LINKING_FAILED\n” << infoLog << endl; } glDeleteShader(vertex); glDeleteShader(fragment); } ~Shader() { glDetachShader(this->Program, vertex); glDetachShader(this->Program, fragment); glDeleteShader(vertex); glDeleteShader(fragment); glDeleteProgram(this->Program); } void Use() { glUseProgram(this->Program); } }; 观察相机:enum Camera_Movement { // 枚举型 FORWARD, // 向前 BACKWARD, // 向后 LEFT, // 向左 RIGHT, // 向右 UPWARD, // 向上 DOWNWARD // 向下 }; const GLfloat SPEED = 6.0f; // 初始速度 class Camera { public: // 构造函数 Camera(glm::vec3 position = glm::vec3(0.0f, 0.0f, 5.0f), glm::vec3 target = glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3 up = glm::vec3(0.0f, 1.0f, 0.0f)) :movementSpeed(SPEED) { this->position = position; this->camera_Z_axis = target; this->camera_Y_axis = up; this->camera_X_axis = glm::normalize(glm::cross(this->camera_Z_axis, this->camera_Y_axis)); this->updateCameraVectors(); // 实时更新 } // 观察矩阵 glm::mat4 GetViewMatrix() { return glm::lookAt(this->position, this->position + this->camera_Z_axis, this->camera_Y_axis); } void ProcessKeyboard(Camera_Movement direction, float deltaTime) { float velocity = this->movementSpeed * deltaTime; if (direction == FORWARD) this->position += this->camera_Z_axis * velocity; if (direction == BACKWARD) this->position -= this->camera_Z_axis * velocity; if (direction == LEFT) this->position -= this->camera_X_axis * velocity; if (direction == RIGHT) this->position += this->camera_X_axis * velocity; if (direction == UPWARD) this->position += this->camera_Y_axis * velocity; if (direction == DOWNWARD) this->position -= this->camera_Y_axis * velocity; } glm::vec3 GetPosition() // 下一篇文章使用 { return this->position; } private: // 摄影机的属性 glm::vec3 position; // 相机当前位置 glm::vec3 camera_Z_axis; // 摄影机的 Z 轴向量 glm::vec3 camera_X_axis; // 摄影机的 X 轴向量 glm::vec3 camera_Y_axis; // 摄影机的 Y 轴向量 GLfloat movementSpeed; // 镜头移动速度 void updateCameraVectors() { this->camera_Z_axis = glm::normalize(this->camera_Z_axis); this->camera_X_axis = glm::normalize(glm::cross(this->camera_Z_axis, this->camera_Y_axis)); this->camera_Y_axis = glm::normalize(glm::cross(this->camera_X_axis, this->camera_Z_axis)); } }; Shader ourShader = Shader(“F:/test/OpenGLTest/shaders/shader_v.txt”, “F:/test/OpenGLTest/shaders/shader_f.txt”); Shader lightShader = Shader(“F:/test/OpenGLTest/shaders/light_v.txt”, “F:/test/OpenGLTest/shaders/light_f.txt”); 可以使用qt相关方式修改自定义着色器,也可以使用QT相关函数替代相关功能,去除自定义着色器,只有相关功能可以实现,之前着色器时从文件中读取的,依旧需要保留从文件中读取,请给出实现后的完整代码以及详细的中文注释,头文件和源文件需要分开,不同在不同文件,不要省略代码,functions()函数不存在
07-30
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值