我无法出现窗口

Question

我是一个正在努力学习的新手程序员。我正在尝试创建一个简单的视频游戏，因此我正在遵循 YouTube 上一个人的指南。

但是，我遇到了一个问题，即使我编译代码并创建

.exe

文件，当我运行该

.exe

文件时什么也没有发生。我尝试操纵代码来让某些事情发生，但什么也没发生。

我尝试更改

CreateWindowExW()

函数并操纵值以显示某些内容，但没有任何进展。没有语法错误，一切都编译干净，我可以制作可执行文件。但是，当我编译它时，没有任何效果。我假设我使用了错误的函数，但我不确定，因为 ChatGPT 告诉我我的代码应该可以工作。

#include <windows.h>

bool running = true;

void*  buffer_memory;
int buffer_width;
int buffer_height;
BITMAPINFO buffer_bitmap_info;
// this controls the memory assigned and allows for good memory allocation
LRESULT CALLBACK window_callback(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
  LRESULT result =0;
  
  switch (uMsg) {
    case WM_CLOSE:
    case WM_DESTROY:
      running = false;
      break;
    
    case WM_SIZE: {
      RECT rect;
      GetClientRect(hwnd, &rect);
      buffer_width = rect.right - rect.left;
      buffer_height = rect.bottom - rect.top;

      int buffer_size = buffer_width*buffer_height *sizeof(unsigned int);
      if(buffer_memory) VirtualFree(buffer_memory, 0, MEM_RELEASE);
      buffer_memory = VirtualAlloc(0, buffer_size, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
    
      buffer_bitmap_info.bmiHeader.biSize = sizeof(buffer_bitmap_info.bmiHeader);
      buffer_bitmap_info.bmiHeader.biWidth = buffer_width;
      buffer_bitmap_info.bmiHeader.biHeight = buffer_height;
      buffer_bitmap_info.bmiHeader.biPlanes = 1;
      buffer_bitmap_info.bmiHeader.biBitCount = 32;
      buffer_bitmap_info.bmiHeader.biCompression = BI_RGB;
    }
      break;
    default: {
      result = DefWindowProc(hwnd, uMsg, wParam, lParam);
    }
  }

  return result;
}

// Creating a typedef function so I can compile without having to link to a library
typedef int (WINAPI* StretchDIBitsFunc)(HDC, int, int, int, int, int, int, int, int, const VOID*, const BITMAPINFO*, UINT, DWORD);

int WinMain(HINSTANCE  hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)
{
  //Create Window Class
  WNDCLASS window_class ={};
  window_class.style = CS_HREDRAW | CS_VREDRAW;
  const wchar_t* WindowName = L"Game Window Class";
  LPCWSTR GameName = L"Ping Pong";
 //window_class.lpszClassName = GameName;
  window_class.lpfnWndProc = window_callback;


  // Register Class
  RegisterClass(&window_class);

  // Create Window
  HWND window = CreateWindowExW(0,WindowName, GameName, WS_OVERLAPPEDWINDOW | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT, 1280, 720, 0, 0, hInstance, 0);
  HDC hdc = GetDC(window);
  StretchDIBitsFunc StretchDIBits = reinterpret_cast<StretchDIBitsFunc>(GetProcAddress(GetModuleHandle(NULL), "StretchDIBits"));

  // Load StretchDIBits function dynamically(so I dont have to link it to a library and it compiles)

  while(running) {
      // Input
      MSG message;
      while(PeekMessage(&message, window, 0, 0, PM_REMOVE)){
        TranslateMessage(&message);
        DispatchMessage(&message);

      }  
      // Simulate
      unsigned int* pixel = (unsigned int*)buffer_memory;
      for (int i = 0; i < buffer_height; i++) {
          for (int z = 0; z < buffer_width; z++) {
              *pixel++ = 0xff5500;
          }           
      }

      // Render 
      if(StretchDIBits){ 
          StretchDIBits(hdc,0,0, buffer_width, buffer_height, 0, 0, buffer_width, buffer_height, buffer_memory, &buffer_bitmap_info, DIB_RGB_COLORS, SRCCOPY);
      }
  }
  return 0;
}

Answer 1

我对发布的代码做了一些更改。尝试一下 -

前两点正如@HansPassant所说。

第三点是记忆

buffer_size

错了，应该是：

stride = ((((biWidth * biBitCount) + 31) & ~31) >> 3);
biSizeImage = abs(biHeight) * stride;

请参阅计算表面步幅了解更多信息。

第四点是参考

StretchDIBits

。

#include <windows.h>

bool running = true;

void* buffer_memory;
int buffer_width;
int buffer_height;
BITMAPINFO buffer_bitmap_info;
// this controls the memory assigned and allows for good memory allocation
LRESULT CALLBACK window_callback(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    LRESULT result = 0;

    switch (uMsg) {
    case WM_CLOSE:
    case WM_DESTROY:
        running = false;
        break;

    case WM_SIZE: {
        RECT rect;
        GetClientRect(hwnd, &rect);
        buffer_width = rect.right - rect.left;
        buffer_height = rect.bottom - rect.top;

        //int buffer_size = buffer_width * buffer_height * sizeof(unsigned int); 3
        int buffer_size = ((buffer_width * 32 + 31) / 32) * 4 * buffer_height;

        if (buffer_memory) VirtualFree(buffer_memory, 0, MEM_RELEASE);
        buffer_memory = VirtualAlloc(0, buffer_size, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);

        buffer_bitmap_info.bmiHeader.biSize = sizeof(buffer_bitmap_info.bmiHeader);
        buffer_bitmap_info.bmiHeader.biWidth = buffer_width;
        buffer_bitmap_info.bmiHeader.biHeight = buffer_height;
        buffer_bitmap_info.bmiHeader.biPlanes = 1;
        buffer_bitmap_info.bmiHeader.biBitCount = 32;
        buffer_bitmap_info.bmiHeader.biCompression = BI_RGB;
    }
                break;
    default: {
        result = DefWindowProc(hwnd, uMsg, wParam, lParam);
    }
    }

    return result;
}

// Creating a typedef function so I can compile without having to link to a library
typedef int (WINAPI* StretchDIBitsFunc)(HDC, int, int, int, int, int, int, int, int, const VOID*, const BITMAPINFO*, UINT, DWORD);

int WinMain(HINSTANCE  hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)
{
    //Create Window Class
    WNDCLASS window_class = {};
    window_class.style = CS_HREDRAW | CS_VREDRAW;
    const wchar_t* WindowName = L"Game Window Class";
    LPCWSTR GameName = L"Ping Pong";
    window_class.lpszClassName = GameName;//1
    window_class.lpfnWndProc = window_callback;


    // Register Class
    RegisterClass(&window_class);

    // Create Window
    //HWND window = CreateWindowExW(0, WindowName, GameName, WS_OVERLAPPEDWINDOW | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT, 1280, 720, 0, 0, hInstance, 0);2
    HWND window = CreateWindowExW(0, GameName, WindowName, WS_OVERLAPPEDWINDOW | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT, 1280, 720, 0, 0, hInstance, 0);
    HDC hdc = GetDC(window);
    //StretchDIBitsFunc StretchDIBits = reinterpret_cast<StretchDIBitsFunc>(GetProcAddress(GetModuleHandle(NULL), "StretchDIBits"));

    // Load StretchDIBits function dynamically(so I dont have to link it to a library and it compiles)

    while (running) {
        // Input
        MSG message;
        while (PeekMessage(&message, window, 0, 0, PM_REMOVE)) {
            TranslateMessage(&message);
            DispatchMessage(&message);

        }
        // Simulate
        unsigned int* pixel = (unsigned int*)buffer_memory;
        for (int i = 0; i < buffer_height; i++) {
            for (int z = 0; z < buffer_width; z++) {
                *pixel++ = 0xff5500;
            }
        }

        // Render 4
        //if (StretchDIBits) {
            StretchDIBits(hdc, 0, 0, buffer_width, buffer_height, 0, 0, buffer_width, buffer_height, buffer_memory, &buffer_bitmap_info, DIB_RGB_COLORS, SRCCOPY);
        //}
    }
    return 0;
}