Question

我尽力制作一款模仿第一人称相机风格的相机。我刚刚从旧的OpenGL渲染方法切换到现在准备处理相机矩阵。这是我的相机更新代码。

void Camera::update(float dt)
{
// Get the distance the camera has moved
float distance = dt * walkSpeed;

// Get the current mouse position
mousePos = mouse->getPosition();

// Translate the change to yaw and pitch
angleYaw -= ((float)mousePos.x-400.0f)*lookSpeed/40;
anglePitch -= ((float)mousePos.y-300.0f)*lookSpeed/40;

// Clamp the camera to a max/min viewing pitch
if(anglePitch > 90.0f)
    anglePitch = 90.0f;

if(anglePitch < -90.0f)
    anglePitch = -90.0f;

// Reset the mouse position
mouse->setPosition(mouseReset);

// Check for movement events
sf::Event event;
while (window->pollEvent(event))
{

    // Calculate the x, y and z values of any movement
    if (event.type == sf::Event::KeyPressed && event.key.code == sf::Keyboard::W)
    {
        position.x -= (float)sin(angleYaw*M_PI/180)*distance*25;
        position.z += (float)cos(angleYaw*M_PI/180)*distance*25;
        position.y += (float)sin(anglePitch * M_PI / 180) * distance * 25;
        angleYaw = 10.0;
    }
    if (event.type == sf::Event::KeyPressed && event.key.code == sf::Keyboard::S)
    {
        position.x += (float)sin(angleYaw*M_PI/180)*distance*25;
        position.z -= (float)cos(angleYaw*M_PI/180)*distance*25;
        position.y -= (float)sin(anglePitch * M_PI / 180) * distance * 25;
    }
    if (event.type == sf::Event::KeyPressed && event.key.code == sf::Keyboard::R)
    {
        position.x += (float)cos(angleYaw*M_PI/180)*distance*25;
        position.z += (float)sin(angleYaw*M_PI/180)*distance*25;
    }
    if (event.type == sf::Event::KeyPressed && event.key.code == sf::Keyboard::A)
    {
        position.x -= (float)cos(angleYaw*M_PI/180)*distance*25;
        position.z -= (float)sin(angleYaw*M_PI/180)*distance*25;
    }
}

// Update our camera matrix
camMatrix = glm::translate(glm::mat4(1.0f), glm::vec3(-position.x, -position.z, -position.y));
camMatrix = glm::rotate(camMatrix, angleYaw, glm::vec3(0, 1, 0));
camMatrix = glm::rotate(camMatrix, anglePitch, glm::vec3(1, 0, 0));
}

最后3行是我假设用相反的翻译更新相机（y和z切换为我正在使用的格式）。我是以错误的顺序做的吗？

这是我非常简单的着色器：

#version 120

attribute vec4 position;
uniform mat4 camera;

void main()
{
    gl_Position = position * camera;
}

#version 120
void main(void)
{
    gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
}

这只是一个红色三角形。相机在三角形周围旋转，这不是我想要的。我想让它旋转相机。我认为将相机矩阵乘以每个顶点会在相机空间中进行渲染。或者我是否需要将它乘以投影矩阵？

移动w，a，s或d会一下子变得非常接近，并且会在整个视图中扭曲整个视图。

Answer 1

以相反的顺序编写矩阵运算。因此，如果您想要翻译（到相机位置）然后旋转，请按以下顺序编写：

// Update our camera matrix
camMatrix = glm::rotate(glm::mat4(1.0f), anglePitch, glm::vec3(1, 0, 0));
camMatrix = glm::rotate(camMatrix, angleYaw, glm::vec3(0, 1, 0));
camMatrix = glm::translate(camMatrix, glm::vec3(-position.x, -position.z, -position.y));

OpenGL - 第一人称相机矩阵问题

1 个答案: