GdipSetPenWidth

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

Status GdipSetPenWidth(
    GpPen* pen,
    FLOAT width
);

<DllImport("gdiplus.dll", ExactSpelling:=True)>
Public Shared Function GdipSetPenWidth(
    pen As IntPtr,   ' GpPen* in/out
    width As Single   ' FLOAT
) As Integer
End Function

' pen : GpPen* in/out
' width : FLOAT
Declare PtrSafe Function GdipSetPenWidth Lib "gdiplus" ( _
    ByVal pen As LongPtr, _
    ByVal width As Single) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

GdipSetPenWidth = ctypes.windll.gdiplus.GdipSetPenWidth
GdipSetPenWidth.restype = ctypes.c_int
GdipSetPenWidth.argtypes = [
    ctypes.c_void_p,  # pen : GpPen* in/out
    ctypes.c_float,  # width : FLOAT
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('gdiplus.dll')
GdipSetPenWidth = Fiddle::Function.new(
  lib['GdipSetPenWidth'],
  [
    Fiddle::TYPE_VOIDP,  # pen : GpPen* in/out
    Fiddle::TYPE_FLOAT,  # width : FLOAT
  ],
  Fiddle::TYPE_INT)

#[link(name = "gdiplus")]
extern "system" {
    fn GdipSetPenWidth(
        pen: *mut GpPen,  // GpPen* in/out
        width: f32  // FLOAT
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("gdiplus.dll")]
public static extern int GdipSetPenWidth(IntPtr pen, float width);
"@
$api = Add-Type -MemberDefinition $sig -Name 'gdiplus_GdipSetPenWidth' -Namespace Win32 -PassThru
# $api::GdipSetPenWidth(pen, width)

#uselib "gdiplus.dll"
#func global GdipSetPenWidth "GdipSetPenWidth" sptr, float
; GdipSetPenWidth varptr(pen), width   ; 戻り値は stat
; pen : GpPen* in/out -> "sptr"
; width : FLOAT -> "float"
; ※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 "gdiplus.dll"
#cfunc global GdipSetPenWidth "GdipSetPenWidth" var, float
; res = GdipSetPenWidth(pen, width)
; pen : GpPen* in/out -> "var"
; width : FLOAT -> "float"
; ※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。

; Status GdipSetPenWidth(GpPen* pen, FLOAT width)
#uselib "gdiplus.dll"
#cfunc global GdipSetPenWidth "GdipSetPenWidth" var, float
; res = GdipSetPenWidth(pen, width)
; pen : GpPen* in/out -> "var"
; width : FLOAT -> "float"
; ※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 (
	"math"
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	gdiplus = windows.NewLazySystemDLL("gdiplus.dll")
	procGdipSetPenWidth = gdiplus.NewProc("GdipSetPenWidth")
)

// pen (GpPen* in/out), width (FLOAT)
r1, _, err := procGdipSetPenWidth.Call(
	uintptr(pen),
	uintptr(math.Float32bits(width)),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // Status
// 注意: float/double 引数は proc.Call では XMM レジスタに渡せません。
// windows.SyscallN(proc.Addr(), math.Float64bits(x), ...) もしくは cgo を使用してください。

function GdipSetPenWidth(
  pen: Pointer;   // GpPen* in/out
  width: Single   // FLOAT
): Integer; stdcall;
  external 'gdiplus.dll' name 'GdipSetPenWidth';

result := DllCall("gdiplus\GdipSetPenWidth"
    , "Ptr", pen   ; GpPen* in/out
    , "Float", width   ; FLOAT
    , "Int")   ; return: Status

●GdipSetPenWidth(pen, width) = DLL("gdiplus.dll", "int GdipSetPenWidth(void*, float)")
# 呼び出し: GdipSetPenWidth(pen, width)
# pen : GpPen* in/out -> "void*"
# width : FLOAT -> "float"
# 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)。