一、FPS摄像机
题目:能否修改摄像机类,使得其能够变成一个真正的FPS摄像机(不能随意飞行,只能待在xz平面上);
在camera.h中的ProcessKeyboard()函数中添加一行代码:Position.y = 0.0f;使y轴一直为0
void ProcessKeyboard(Camera_Movement direction, float deltaTime){float velocity = MovementSpeed * deltaTime;if (direction == FORWARD)Position += Front * velocity;if (direction == BACKWARD)Position -= Front * velocity;if (direction == LEFT)Position -= Right * velocity;if (direction == RIGHT)Position += Right * velocity;Position.y = 0.0f;}
二、创建观察矩阵
题目:手动创建一个观察矩阵,替换LookAt()函数;
QMatrix4x4 myLookAt(QVector3D position, QVector3D target, QVector3D worldUp)
{//z轴向量(摄像机反方向)QVector3D zaxis = QVector3D(position - target); //摄像机的位置 - 原点zaxis.normalize();worldUp.normalize();//x轴向量(右轴)QVector3D xaxis = QVector3D::crossProduct(worldUp, zaxis);xaxis.normalize();//y轴向量(上轴)QVector3D yaxis = QVector3D::crossProduct(zaxis, xaxis); QMatrix4x4 translation; QVector4D theVector4D;theVector4D.setX(-position.x()); // Third column, first rowtheVector4D.setY(-position.y());theVector4D.setZ(-position.z());theVector4D.setW(1.0);translation.setColumn(3,theVector4D);QMatrix4x4 rotation;theVector4D.setX(xaxis.x()); // First column, first rowtheVector4D.setY(xaxis.y());theVector4D.setZ(xaxis.z());theVector4D.setW(0.0);rotation.setColumn(0,theVector4D);theVector4D.setX(yaxis.x()); theVector4D.setY(yaxis.y());theVector4D.setZ(yaxis.z());theVector4D.setW(0.0);rotation.setColumn(1,theVector4D);theVector4D.setX(zaxis.x());theVector4D.setY(zaxis.y());theVector4D.setZ(zaxis.z());theVector4D.setW(0.0);rotation.setColumn(2,theVector4D);return rotation * translation;
}
注:观看OpenGL中文官网(https://learnopengl-cn.github.io/)和阿西拜的现代OpenGL入门(https://ke.qq.com/course/3999604#term_id=104150693)学习OpenGL