在C++ DirectX中計算View Matrix 9

Question

我正在嘗試爲我的DirectX遊戲創建第一人稱射擊相機。但我努力試圖讓我的觀點矩陣正確。目前我只有一個三角形顯示在屏幕上，但是當我旋轉相機並向前移動時，似乎三角形正在相機周圍旋轉。這裏是我的相機類完成的代碼

Camera.h

#pragma once 

#include"Window.h" 
#include"Matrix.h" 
#include "Vector3.h" 

class Camera 
{ 
public: 
    Camera(); 
    Camera(float pitch, float yaw, Vector3 position); 
    ~Camera(); 

    void Update(); 

    D3DXMATRIX BuildViewMatrix(); 

    Vector3 GetPosition() const { return position; } 
    void SetPosition(Vector3 val) { position = val; } 

protected: 
    float yaw; 
    float pitch; 
    Vector3 position; 
}; 

Camera.cpp

#include"Camera.h" 
Camera::Camera() 
{ 
    yaw = 0.0f; 
    pitch = 0.0f; 
} 

Camera::Camera(float pitch, float yaw, Vector3 position) 
{ 
    this->pitch = pitch; 
    this->yaw = yaw; 
    this->position = position; 
} 

Camera::~Camera() 
{ 
} 

void Camera::Update() 
{ 
    pitch = min(pitch, 90.0f); 
    pitch = max(pitch, -90.0f); 

    if(yaw < 0) 
     yaw += 360.0f; 

    if(yaw > 360.0f) 
     yaw -= 360.0f; 


    if(Window::GetKeyboard()->KeyDown(KEYBOARD_W)) 
    { 
     D3DXMATRIX translateMat; 
     D3DXMatrixTranslation(&translateMat, position.x, position.y, position.z); 

     D3DXMATRIX rotationMat; 
     D3DXMatrixRotationY(&rotationMat, D3DXToRadian(yaw)); 

     D3DXMATRIX forwardMat; 
     D3DXMatrixTranslation(&forwardMat, 0.0f, 0.0f, 10.0f); 

     D3DXMATRIX transformMat = translateMat * rotationMat * forwardMat; 

     position.x = transformMat._41; 
     position.y = transformMat._42; 
     position.z = transformMat._43; 

     std::cout << "X: " << transformMat._41 << std::endl; 
     std::cout << "Y: " << transformMat._42 << std::endl; 
     std::cout << "Z: " << transformMat._43 << std::endl; 
    } 
    else if(Window::GetKeyboard()->KeyDown(KEYBOARD_S)) 
    { 
    D3DXMATRIX translateMat; 
    D3DXMatrixTranslation(&translateMat, position.x, position.y, position.z); 

    D3DXMATRIX rotationMat; 
    D3DXMatrixRotationY(&rotationMat, D3DXToRadian(yaw)); 

    D3DXMATRIX forwardMat; 
    D3DXMatrixTranslation(&forwardMat, 0.0f, 0.0f, -10.0f); 

    D3DXMATRIX transformMat = translateMat * rotationMat * forwardMat; 

    position.x = transformMat._41; 
    position.y = transformMat._42; 
    position.z = transformMat._43; 

    std::cout << "X: " << transformMat._41 << std::endl; 
    std::cout << "Y: " << transformMat._42 << std::endl; 
    std::cout << "Z: " << transformMat._43 << std::endl; 
    } 


    if(Window::GetKeyboard()->KeyDown(KEYBOARD_Q)) 
    { 
     yaw = yaw - 1.0f; 
    } 

    if(Window::GetKeyboard()->KeyDown(KEYBOARD_E)) 
    { 
     yaw = yaw + 1.0f; 
    } 
} 

D3DXMATRIX Camera::BuildViewMatrix() 
{ 
    D3DXMATRIX translationMat; 
    D3DXMatrixTranslation(&translationMat, (position.x * -1.0f), (position.y * -1.0f), (position.z * -1.0f)); 

    D3DXMATRIX yawMat; 
    D3DXMatrixRotationY(&yawMat, D3DXToRadian((yaw * -1.0f))); 

    D3DXMATRIX pitchMat; 
    D3DXMatrixRotationX(&pitchMat, D3DXToRadian((pitch * -1.0f))); 

    D3DXMATRIX viewMat = pitchMat * yawMat * translationMat; 

    return viewMat; 
} 

我使用device->SetTransform(D3DTS_VIEW, &camera->BuildViewMatrix());到視圖矩陣發送到的DirectX。我究竟做錯了什麼？請幫助

UPDATE：

我修改了代碼，並試圖用D3DXMatrixLookAtLH功能（不使用相機的話），但是這一次，它不會做任何事情 - 無論我如何更改函數的LookAt參數，三角形都保持在同一位置。下面是它的代碼：

void Renderer::Render() 
{ 
    device->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(40, 40, 40), 1.0f, 0); 

    device->BeginScene(); //Must be used as it tells DirectX we're starting to draw stuff. 

    D3DXMATRIX worldMat; 
    D3DXMatrixTranslation(&worldMat, 0.0f, 0.0f, 0.0f); 
    device->SetTransform(D3DTS_WORLD, &worldMat); 

    D3DXMATRIX viewMatrix; 
    D3DXMatrixLookAtLH(&viewMatrix, 
         &D3DXVECTOR3(0.0f, -100.0f, 1000.0f), //position 
         &D3DXVECTOR3(0.0f, 1.0f, 0.0f), //Look at 
         &D3DXVECTOR3(0.0f, 1.0f, 0.0f)); 
    device->SetTransform(D3DTS_VIEW, &viewMatrix); 
    //device->SetTransform(D3DTS_VIEW, &camera->BuildViewMatrix()); 

    D3DXMATRIX projMatrix; 
    D3DXMatrixPerspectiveFovLH(&projMatrix, 
           D3DXToRadian(45), 
           (float)width/(float)height, 
           1.0f, 
           10000.0f); 
    device->SetTransform(D3DTS_PROJECTION, &projMatrix); 

    device->SetFVF(VERTEXFORMAT); 
    device->SetStreamSource(0, vertexBuffer, 0, sizeof(VERTEX)); 
    device->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1); 

    device->EndScene(); //Thank you for waiting, I have finished drawing stuff on the screen, please handle the rest Mr DirectX. 

    device->Present(NULL, NULL, NULL, NULL); 
} 

Answer 1

發現了問題，我已經計算出的矩陣是不正確的，以及觀察矩陣。通過添加以下代碼固定它：

Camera.h

#pragma once 

#pragma comment(lib, "d3dx9.lib") 
#include<d3dx9math.h> 

#include"Window.h" 

class Camera 
{ 
public: 
    Camera(); 
    Camera(float pitch, float yaw, D3DXVECTOR3 position); 
    ~Camera(); 

    void Update(); 

    D3DXMATRIX BuildViewMatrix(); 

    inline D3DXVECTOR3 GetPosition() const { return position; } 
    inline void SetPosition(D3DXVECTOR3 position){ this->position = position;} 

protected: 
    float yaw; 
    float pitch; 
    float roll; 
    D3DXVECTOR3 position; 

private: 
    D3DXVECTOR3 xAxis; 
    D3DXVECTOR3 yAxis; 
    D3DXVECTOR3 zAxis; 
}; 

Camera.cpp

#include"Camera.h" 
Camera::Camera() 
{ 
    yaw = 0.0f; 
    pitch = 0.0f; 
    roll = 0.0f; 
} 

//yaw = head twist 
//pitch = head tilt 
Camera::Camera(float pitch, float yaw, D3DXVECTOR3 position) 
{ 
    this->pitch = pitch; 
    this->yaw = yaw; 
    roll = 0.0f; 
    this->position = position; 

    xAxis = D3DXVECTOR3(1.0f, 0.0f, 0.0f); 
    yAxis = D3DXVECTOR3(0.0f, 1.0f, 0.0f); 
    zAxis = D3DXVECTOR3(0.0f, 0.0f, 1.0f); 
} 

Camera::~Camera() 
{ 

} 

void Camera::Update() 
{ 

    if(Window::GetKeyboard()->KeyDown(KEYBOARD_Q)){ 
     yaw -= 1.0f; 
    } 
    else if(Window::GetKeyboard()->KeyDown(KEYBOARD_E)){ 
     yaw += 1.0f; 
    } 

    if(Window::GetKeyboard()->KeyDown(KEYBOARD_Z)){ 
     pitch += 1.0f; 
    } 
    else if(Window::GetKeyboard()->KeyDown(KEYBOARD_X)){ 
     pitch -= 1.0f; 
    } 

    pitch = min(pitch, 90.0f); 
    pitch = max(pitch, -90.0f); 

    if(yaw < 0.0f) 
     yaw += 360.0f; 

    if(yaw > 360.0f) 
     yaw -= 360.0f; 


    D3DXMATRIX yawMat; 
    D3DXMatrixRotationAxis(&yawMat, &yAxis, D3DXToRadian(yaw)); 
    D3DXVec3TransformCoord(&zAxis, &zAxis, &yawMat); 
    D3DXVec3TransformCoord(&xAxis, &xAxis, &yawMat); 

    D3DXMATRIX pitchMat; 
    D3DXMatrixRotationAxis(&pitchMat, &xAxis, D3DXToRadian(pitch)); 
    D3DXVec3TransformCoord(&zAxis, &zAxis, &pitchMat); 
    D3DXVec3TransformCoord(&yAxis, &yAxis, &pitchMat); 

    D3DXMATRIX rollMat; 
    D3DXMatrixRotationAxis(&rollMat, &zAxis, D3DXToRadian(0.0f)); 
    D3DXVec3TransformCoord(&xAxis, &xAxis, &rollMat); 
    D3DXVec3TransformCoord(&yAxis, &yAxis, &rollMat); 

    if(Window::GetKeyboard()->KeyDown(KEYBOARD_W)) 
    { 
     position = position + (zAxis * -1) * 10.0f; 
    } 
    else if(Window::GetKeyboard()->KeyDown(KEYBOARD_S)) 
    { 
     position = position + zAxis * 10.0f; 
    } 

    if(Window::GetKeyboard()->KeyDown(KEYBOARD_A)) 
    { 
     position = position + xAxis * 10.0f; 
    } 
    else if(Window::GetKeyboard()->KeyDown(KEYBOARD_D)) 
    { 
     position = position - xAxis * 10.0f; 
    } 

    yaw = 0.0f; 
    pitch = 0.0f; 
    roll = 0.0f; 
} 

D3DXMATRIX Camera::BuildViewMatrix() 
{ 
    D3DXMATRIX viewMatrix; 
    D3DXMatrixIdentity(&viewMatrix); 

    viewMatrix._11 = xAxis.x; 
    viewMatrix._21 = xAxis.y; 
    viewMatrix._31 = xAxis.z; 

    viewMatrix._12 = yAxis.x; 
    viewMatrix._22 = yAxis.y; 
    viewMatrix._32 = yAxis.z; 

    viewMatrix._13 = zAxis.x; 
    viewMatrix._23 = zAxis.y; 
    viewMatrix._33 = zAxis.z; 

    viewMatrix._41 = D3DXVec3Dot(&position, &xAxis); 
    viewMatrix._42 = D3DXVec3Dot(&position, &yAxis); 
    viewMatrix._43 = D3DXVec3Dot(&position, &zAxis); 

    return viewMatrix; 
}