CreatePolygonRgn

// GDI32.dll
#include <windows.h>

HRGN CreatePolygonRgn(
    const POINT* pptl,
    INT cPoint,
    CREATE_POLYGON_RGN_MODE iMode
);

<DllImport("GDI32.dll", ExactSpelling:=True)>
Public Shared Function CreatePolygonRgn(
    pptl As IntPtr,   ' POINT*
    cPoint As Integer,   ' INT
    iMode As Integer   ' CREATE_POLYGON_RGN_MODE
) As IntPtr
End Function

' pptl : POINT*
' cPoint : INT
' iMode : CREATE_POLYGON_RGN_MODE
Declare PtrSafe Function CreatePolygonRgn Lib "gdi32" ( _
    ByVal pptl As LongPtr, _
    ByVal cPoint As Long, _
    ByVal iMode As Long) As LongPtr
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

CreatePolygonRgn = ctypes.windll.gdi32.CreatePolygonRgn
CreatePolygonRgn.restype = ctypes.c_void_p
CreatePolygonRgn.argtypes = [
    ctypes.c_void_p,  # pptl : POINT*
    ctypes.c_int,  # cPoint : INT
    ctypes.c_int,  # iMode : CREATE_POLYGON_RGN_MODE
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('GDI32.dll')
CreatePolygonRgn = Fiddle::Function.new(
  lib['CreatePolygonRgn'],
  [
    Fiddle::TYPE_VOIDP,  # pptl : POINT*
    Fiddle::TYPE_INT,  # cPoint : INT
    Fiddle::TYPE_INT,  # iMode : CREATE_POLYGON_RGN_MODE
  ],
  Fiddle::TYPE_VOIDP)

#[link(name = "gdi32")]
extern "system" {
    fn CreatePolygonRgn(
        pptl: *const POINT,  // POINT*
        cPoint: i32,  // INT
        iMode: i32  // CREATE_POLYGON_RGN_MODE
    ) -> *mut core::ffi::c_void;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("GDI32.dll")]
public static extern IntPtr CreatePolygonRgn(IntPtr pptl, int cPoint, int iMode);
"@
$api = Add-Type -MemberDefinition $sig -Name 'GDI32_CreatePolygonRgn' -Namespace Win32 -PassThru
# $api::CreatePolygonRgn(pptl, cPoint, iMode)

#uselib "GDI32.dll"
#func global CreatePolygonRgn "CreatePolygonRgn" sptr, sptr, sptr
; CreatePolygonRgn varptr(pptl), cPoint, iMode   ; 戻り値は stat
; pptl : POINT* -> "sptr"
; cPoint : INT -> "sptr"
; iMode : CREATE_POLYGON_RGN_MODE -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "GDI32.dll"
#cfunc global CreatePolygonRgn "CreatePolygonRgn" var, int, int
; res = CreatePolygonRgn(pptl, cPoint, iMode)
; pptl : POINT* -> "var"
; cPoint : INT -> "int"
; iMode : CREATE_POLYGON_RGN_MODE -> "int"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

; HRGN CreatePolygonRgn(POINT* pptl, INT cPoint, CREATE_POLYGON_RGN_MODE iMode)
#uselib "GDI32.dll"
#cfunc global CreatePolygonRgn "CreatePolygonRgn" var, int, int
; res = CreatePolygonRgn(pptl, cPoint, iMode)
; pptl : POINT* -> "var"
; cPoint : INT -> "int"
; iMode : CREATE_POLYGON_RGN_MODE -> "int"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	gdi32 = windows.NewLazySystemDLL("GDI32.dll")
	procCreatePolygonRgn = gdi32.NewProc("CreatePolygonRgn")
)

// pptl (POINT*), cPoint (INT), iMode (CREATE_POLYGON_RGN_MODE)
r1, _, err := procCreatePolygonRgn.Call(
	uintptr(pptl),
	uintptr(cPoint),
	uintptr(iMode),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRGN

function CreatePolygonRgn(
  pptl: Pointer;   // POINT*
  cPoint: Integer;   // INT
  iMode: Integer   // CREATE_POLYGON_RGN_MODE
): THandle; stdcall;
  external 'GDI32.dll' name 'CreatePolygonRgn';

result := DllCall("GDI32\CreatePolygonRgn"
    , "Ptr", pptl   ; POINT*
    , "Int", cPoint   ; INT
    , "Int", iMode   ; CREATE_POLYGON_RGN_MODE
    , "Ptr")   ; return: HRGN

●CreatePolygonRgn(pptl, cPoint, iMode) = DLL("GDI32.dll", "void* CreatePolygonRgn(void*, int, int)")
# 呼び出し: CreatePolygonRgn(pptl, cPoint, iMode)
# pptl : POINT* -> "void*"
# cPoint : INT -> "int"
# iMode : CREATE_POLYGON_RGN_MODE -> "int"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。