3D cube render, basic interpolation, culling

platform.cpp

@@ -0,0 +1,146 @@
+#include "platform.h"
+#include <windows.h>
+#include <math.h>
+
+Image screen;
+float* depth_buffer;
+bool keydown_a;
+bool keydown_b;
+
+GLOBAL bool g_app_is_running = true;
+GLOBAL HBITMAP g_screen_dib;
+GLOBAL HDC g_screen_dc;
+GLOBAL HDC g_window_dc;
+GLOBAL HWND g_hwnd;
+GLOBAL HINSTANCE g_hinstance;
+GLOBAL int g_cmdshow;
+
+#include <shellscalingapi.h>
+typedef HRESULT tSetProcessDpiAwareness(PROCESS_DPI_AWARENESS);
+
+FUNCTION
+LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
+  LRESULT result = 0;
+  switch (uMsg) {
+  case WM_CLOSE: DestroyWindow(hwnd); g_app_is_running = false; break;
+  case WM_DESTROY: PostQuitMessage(0); g_app_is_running = false; break;
+  case WM_SYSKEYDOWN:
+  case WM_KEYDOWN: {
+    switch (wParam) {
+    case VK_ESCAPE: g_app_is_running = false; break;
+    case 0x4F: keydown_a = true; break;
+    case 0x50: keydown_b = true; break;
+    }
+  } break;
+  case WM_SYSKEYUP:
+  case WM_KEYUP: {
+    switch (wParam) {
+    case 0x4F: keydown_a = false; break;
+    case 0x50: keydown_b = false; break;
+    }
+  } break;
+  default: result = DefWindowProc(hwnd, uMsg, wParam, lParam);
+  }
+  return result;
+}
+
+FUNCTION
+void Win32_ScreenInit(int window_x, int window_y) {
+  BITMAPINFO bminfo = {};
+  bminfo.bmiHeader.biSize = sizeof(bminfo.bmiHeader);
+  bminfo.bmiHeader.biWidth = window_x;
+  bminfo.bmiHeader.biHeight = -window_y;
+  bminfo.bmiHeader.biPlanes = 1;
+  bminfo.bmiHeader.biBitCount = 32;
+  bminfo.bmiHeader.biCompression = BI_RGB; // AA RR GG BB
+  bminfo.bmiHeader.biXPelsPerMeter = 1;
+  bminfo.bmiHeader.biYPelsPerMeter = 1;
+
+  void* mem = 0;
+  g_screen_dib = CreateDIBSection(g_window_dc, &bminfo, DIB_RGB_COLORS, (void**)&mem, 0, 0);
+  g_screen_dc = CreateCompatibleDC(g_window_dc);
+  screen.pixels = (uint32_t*)mem;
+  depth_buffer = (float*)malloc(window_x * window_y * sizeof(float));
+  screen.x = window_x;
+  screen.y = window_y;
+}
+
+void OS_Init(OSInitArgs i) {
+  HMODULE shcore = LoadLibraryA("Shcore.dll");
+  if (shcore) {
+    tSetProcessDpiAwareness* set_dpi_awr = (tSetProcessDpiAwareness*)GetProcAddress(shcore, "SetProcessDpiAwareness");
+    if (set_dpi_awr) {
+      HRESULT hr = set_dpi_awr(PROCESS_PER_MONITOR_DPI_AWARE);
+      ASSERT(SUCCEEDED(hr));
+    }
+  }
+
+  const wchar_t CLASS_NAME[] = L"Hello!";
+  WNDCLASS wc = { };
+  wc.lpfnWndProc = WindowProc;
+  wc.hInstance = g_hinstance;
+  wc.lpszClassName = CLASS_NAME;
+  RegisterClass(&wc);
+
+  g_hwnd = CreateWindowEx(
+    0,                              // Optional window styles.
+    CLASS_NAME,                     // Window class
+    L"Have a wonderful day!",    // Window text
+    WS_OVERLAPPEDWINDOW,            // Window style
+    CW_USEDEFAULT, CW_USEDEFAULT, i.window_x, i.window_y, // Size and position
+    NULL,       // Parent window    
+    NULL,       // Menu
+    g_hinstance,  // Instance handle
+    NULL        // Additional application data
+  );
+  ASSERT(g_hwnd != 0);
+
+  ShowWindow(g_hwnd, g_cmdshow);
+  RECT rect;
+  GetWindowRect(g_hwnd, &rect);
+  g_window_dc = GetWindowDC(g_hwnd);
+  Win32_ScreenInit(rect.right - rect.left, rect.bottom - rect.top);
+}
+
+bool OS_GameLoop() {
+  MSG msg = { };
+  while (PeekMessage(&msg, 0, 0, 0, PM_REMOVE) > 0) {
+    TranslateMessage(&msg);
+    DispatchMessage(&msg);
+  }
+
+  // @Note: Free the screen on window resize
+  RECT rect;
+  GetWindowRect(g_hwnd, &rect);
+  int new_width = rect.right - rect.left;
+  int new_height = rect.bottom - rect.top;
+  if (new_width != screen.x || new_height != screen.y) {
+    screen.x = new_width;
+    screen.y = new_height;
+    if (screen.pixels) {
+      screen.pixels = 0;
+      free(depth_buffer);
+      DeleteDC(g_screen_dc);
+      DeleteObject(g_screen_dib);
+    }
+  }
+
+  // @Note: Create drawable screen
+  if (!screen.pixels) {
+    Win32_ScreenInit((LONG)screen.x, (LONG)screen.y);
+  }
+
+
+  // @Note; Draw screen to window
+  SelectObject(g_screen_dc, g_screen_dib);
+  BitBlt(g_window_dc, 0, 0, screen.x, screen.y, g_screen_dc, 0, 0, SRCCOPY);
+  Sleep(16);
+  return g_app_is_running;
+}
+
+int main();
+int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow) {
+  g_hinstance = hInstance;
+  g_cmdshow = nCmdShow;
+  return main();
+}