glVertex2f

// OPENGL32.dll
#include <windows.h>

void glVertex2f(
    FLOAT x,
    FLOAT y
);

<DllImport("OPENGL32.dll", ExactSpelling:=True)>
Public Shared Sub glVertex2f(
    x As Single,   ' FLOAT
    y As Single   ' FLOAT
)
End Sub

' x : FLOAT
' y : FLOAT
Declare PtrSafe Sub glVertex2f Lib "opengl32" ( _
    ByVal x As Single, _
    ByVal y As Single)
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

glVertex2f = ctypes.windll.opengl32.glVertex2f
glVertex2f.restype = None
glVertex2f.argtypes = [
    ctypes.c_float,  # x : FLOAT
    ctypes.c_float,  # y : FLOAT
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('OPENGL32.dll')
glVertex2f = Fiddle::Function.new(
  lib['glVertex2f'],
  [
    Fiddle::TYPE_FLOAT,  # x : FLOAT
    Fiddle::TYPE_FLOAT,  # y : FLOAT
  ],
  Fiddle::TYPE_VOID)

#[link(name = "opengl32")]
extern "system" {
    fn glVertex2f(
        x: f32,  // FLOAT
        y: f32  // FLOAT
    );
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("OPENGL32.dll")]
public static extern void glVertex2f(float x, float y);
"@
$api = Add-Type -MemberDefinition $sig -Name 'OPENGL32_glVertex2f' -Namespace Win32 -PassThru
# $api::glVertex2f(x, y)

#uselib "OPENGL32.dll"
#func global glVertex2f "glVertex2f" float, float
; glVertex2f x, y
; x : FLOAT -> "float"
; y : FLOAT -> "float"

#uselib "OPENGL32.dll"
#func global glVertex2f "glVertex2f" float, float
; glVertex2f x, y
; x : FLOAT -> "float"
; y : FLOAT -> "float"

; void glVertex2f(FLOAT x, FLOAT y)
#uselib "OPENGL32.dll"
#func global glVertex2f "glVertex2f" float, float
; glVertex2f x, y
; x : FLOAT -> "float"
; y : FLOAT -> "float"

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

var (
	opengl32 = windows.NewLazySystemDLL("OPENGL32.dll")
	procglVertex2f = opengl32.NewProc("glVertex2f")
)

// x (FLOAT), y (FLOAT)
r1, _, err := procglVertex2f.Call(
	uintptr(math.Float32bits(x)),
	uintptr(math.Float32bits(y)),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // void
// 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。

procedure glVertex2f(
  x: Single;   // FLOAT
  y: Single   // FLOAT
); stdcall;
  external 'OPENGL32.dll' name 'glVertex2f';

result := DllCall("OPENGL32\glVertex2f"
    , "Float", x   ; FLOAT
    , "Float", y   ; FLOAT
    , "Int")   ; return: void

●glVertex2f(x, y) = DLL("OPENGL32.dll", "int glVertex2f(float, float)")
# 呼び出し: glVertex2f(x, y)
# x : FLOAT -> "float"
# y : 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)。