implement window drawing

.gitignore

@@ -0,0 +1,2 @@
+/build/*
+!/build/.gitk

code/.clangd

@@ -0,0 +1,9 @@
+CompileFlags:
+  Add:
+    - "--target=x86_64-w64-windows-gnu"
+    - "-isystem"
+    - "/usr/lib/zig/libc/include/any-windows-any"
+    - "-isystem"
+    - "/usr/lib/zig/libc/include/generic-musl"
+    - "-D_WIN32"
+    - "-D_X86_64_"

code/Makefile

@@ -0,0 +1,5 @@
+comp:
+	zig c++ --target=x86_64-windows -o ../build/win32_handmade.exe win32_handmade.cpp -lgdi32
+.PHONY: clean
+clean: 
+	rm ../build/*

code/win32_handmade.cpp

@@ -0,0 +1,83 @@
+#include <stdio.h>
+#include <windows.h>
+#include <wingdi.h>
+
+LRESULT CALLBACK MainWindowCallback(HWND window, UINT message, WPARAM wParam,
+                                    LPARAM lParam) {
+  LRESULT res = 0;
+  switch (message) {
+  case WM_SIZE: {
+    printf("WM_SIZE\n");
+  } break;
+  case WM_DESTROY: {
+    printf("WM_DESTROY\n");
+  } break;
+  case WM_CLOSE: {
+    printf("WM_CLOSE\n");
+  } break;
+  case WM_PAINT: {
+    PAINTSTRUCT paint;
+    HDC deviceContext = BeginPaint(window, &paint);
+    int height = paint.rcPaint.bottom - paint.rcPaint.top;
+    int width = paint.rcPaint.right - paint.rcPaint.left;
+    int x = paint.rcPaint.left;
+    int y = paint.rcPaint.top;
+
+    static DWORD operation = WHITENESS;
+    PatBlt(deviceContext, x, y, width, height, operation);
+    if (operation == WHITENESS) {
+      operation = BLACKNESS;
+    } else {
+      operation = WHITENESS;
+    }
+    EndPaint(window, &paint);
+  } break;
+  case WM_ACTIVATEAPP: {
+    printf("WM_ACTIVATEAPP\n");
+  } break;
+  default: {
+    // printf("WM_ACTIVATEAPP\n");
+    res = DefWindowProc(window, message, wParam, lParam);
+  } break;
+  }
+
+  return res;
+}
+
+int CALLBACK WinMain(HINSTANCE instance, HINSTANCE prevInstance,
+                     LPSTR commandLine, int showCode) {
+  WNDCLASS WindowClass = {0};
+  WindowClass.style = CS_OWNDC | CS_HREDRAW | CS_VREDRAW;
+  WindowClass.lpfnWndProc = MainWindowCallback;
+  // WindowClass.cbClsExtra = ;
+  // WindowClass.cbWndExtra = ;
+  WindowClass.hInstance = instance;
+  // WindowClass.hIcon = ;
+  // WindowClass.hCursor = ;
+  // WindowClass.lpszMenuName = ;
+  WindowClass.lpszClassName = "HandmadeHeroWindowClass";
+
+  if (RegisterClass(&WindowClass)) {
+    HWND windowHandle = CreateWindowEx(
+        0, WindowClass.lpszClassName, "Handmade Hero",
+        WS_OVERLAPPEDWINDOW | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT,
+        CW_USEDEFAULT, CW_USEDEFAULT, 0, 0, instance, 0);
+    if (windowHandle) {
+      MSG message;
+      for (;;) {
+        BOOL msgResult = GetMessage(&message, 0, 0, 0);
+        if (msgResult > 0) {
+          TranslateMessage(&message);
+          DispatchMessage(&message);
+        } else {
+          break;
+        }
+      }
+    } else {
+      // TODO: log?
+    }
+  } else {
+    // TODO: log?
+  }
+  return (0);
+}