Geometric algorithms region pointer Whether the coordinates are within the shape area algorithm How to check if a given point lies inside or outside a polygon?

How to create an algorithm that can determine if a point is contained in an irregular polygon defined by the points of its corners
ray casting algorithm
https://en.wikipedia.org/wiki/Ray_casting
https://www.researchgate.net/figure/Illustration-of-the-Ray-Casting-Algorithm_fig5_259468883

https://gistbok.ucgis.org/bok-topics/geometric-primitives-and-algorithms
Computational Geometry Algorithms and Applications
https://www.geeksforgeeks.org/geometric-algorithms/
https://www.geeksforgeeks.org/c-program-find-area-triangle/
https://demonstrations.wolfram.com/AnEfficientTestForAPointToBeInAConvexPolygon/
https://www.sciencedirect.com/science/article/pii/S0925772115000759
https://www.geeksforgeeks.org/how-to-check-if-a-given-point-lies-inside-a-polygon/

ray casting algorithm Geometric algorithms region pointer Whether the coordinates are within the shape area
https://www.scribd.com/document/56214673/Ray-Casting-Algorithm
https://rosettacode.org/wiki/Ray-casting_algorithm
https://stackoverflow.com/questions/217578/how-can-i-determine-whether-a-2d-point-is-within-a-polygon
https://octave.sourceforge.io/geometry/function/clipPolygon_clipper.html
https://www.researchgate.net/figure/An-example-of-no-fit-polygon-NFP_fig7_228553279

gui window regions SetWindowRgn SelectClipPath SelectClipRgn OffsetClipRgn ExcludeClipRect IntersetClipRec SelectClipPath

 gui window regions  

SetWindowRgn SelectClipPath    

OffsetClipRgn ExcludeClipRect   SelectClipPath
ExcludeClipRect

https://www.codeproject.com/Articles/2095/A-Guide-to-WIN32-Clipping-Regions

https://stackoverflow.com/questions/38891350/search-icon-in-edit-control-overlapped-by-input-area
https://learn.microsoft.com/zh-tw/windows/win32/api/wingdi/nf-wingdi-excludecliprect?redirectedfrom=MSDN
https://stackoverflow.com/questions/70930821/mfc-how-to-add-clear-button-inside-cedit
https://www.codeproject.com/Articles/35722/MFC-Feature-Pack-CMFCEditBrowseCtrl
https://www.codeproject.com/Articles/738/Enhanced-Focus-Edit-Control-with-Input-Filtering
https://stackoverflow.com/questions/17941527/changing-the-background-of-an-edit-control-on-getting-focus
https://stackoverflow.com/questions/8695185/why-my-edit-control-looks-odd-in-my-win32-c-application-using-no-mfc
 https://www.codeproject.com/Articles/20193/The-Ultimate-Toolbox-Edit-Control-Extensions
https://www.codeproject.com/Articles/1944/Guide-to-WIN32-Regions
https://learn.microsoft.com/en-us/windows/win32/learnwin32/painting-the-window
gui window regions  SetWindowRgn

gui window regions Hdc


https://www.geeksforgeeks.org/introduction-to-r-tree/
http://postgis.net/workshops/postgis-intro/indexing.html
https://github.com/StefanSalewski/RTree
http://www.gitta.info/SpatPartitio/en/html/ObjOriDecomp_learningObject2.html
https://www.pbr-book.org/3ed-2018/Primitives_and_Intersection_Acceleration/Kd-Tree_Accelerator

https://gopalcdas.com/2017/05/24/construction-of-k-d-tree-and-using-it-for-nearest-neighbour-search/
https://www.vlfeat.org/overview/kdtree.html

https://commons.wikimedia.org/wiki/File:Kd_tree_vs_skd_tree.svg
https://gamedev.stackexchange.com/questions/30208/what-is-the-kd-tree-intersection-logic

https://zh.wikipedia.org/zh-tw/K-d%E6%A0%91
https://en.wikipedia.org/wiki/R-tree


https://commons.wikimedia.org/wiki/Category:Computational_geometry

algorithm windows dc handle system HWND selectObject Device Contexts

 algorithm windows dc handle system HWND selectObject Device Contexts

https://learn.microsoft.com/zh-tw/cpp/mfc/relationship-between-a-cpp-window-object-and-an-hwnd?view=msvc-170

capable of drawing lines, arrows, rectangles, and ellipses. It is also capable of writing and editing text, cut-and-paste figures as well as saving and loading the drawings. The following screenshot depicts a classic example of the Draw Application:

https://learn.microsoft.com/en-us/windows/win32/gdi/using-filled-shapes
https://www.codeproject.com/articles/1698/ms-spy-style-window-finder?fid=3083&df=90&mpp=25&prof=true&sort=position&view=normal&spc=relaxed&fr=26
https://www.codeproject.com/Articles/8216/Writing-Win32-Apps-with-C-V2-part-1
https://www.codeproject.com/Articles/1944/Guide-to-WIN32-Regions

windows mouse  notification system  region pointer grab cursor HDC Handle of Window Handle to Device Context
http://www.cs.sjsu.edu/~pearce/modules/lectures/mfc/chp4/chapter4.htm
https://stackoverflow.com/questions/72566733/how-to-highlight-mouse-pointer-position-using-delphi
https://stackoverflow.com/questions/66848052/how-capture-only-the-region-of-mouse-click-on-screen

https://www.hiramine.com/programming/modelvieweropenglwinapi2008/01_base.html
http://uglab.blog23.fc2.com/blog-entry-110.html
http://www.kab-studio.biz/Programing/Codian/MxA/05.html
https://claybird.sakura.ne.jp/tips/gl_01/index.html

algorithm microwindows windows  select Object

algorithm microwindows windows  select   Handle  Device Contex
https://www.researchgate.net/figure/Sliding-window-algorithm-explanation_fig1_228753893
https://www.informit.com/articles/article.aspx?p=30009&seqNum=4
windows hdc Handle Device Context area mouse click event

gui win system mouse cursor pointer get windows controls handle algorithm search HDC Region
https://www.codeproject.com/Articles/5178828/The-Explorer-Imperative-Two-Stage-Search
https://learn.microsoft.com/en-us/windows/win32/learnwin32/painting-the-window
gui win  mouse cursor handle algorithm search HDC Region
region gui screen region selector

https://github.com/country-regions/react-country-region-selector#demo
gui  Regions  custom region selection SelectObject Polygonal Region Structures
https://github.com/SerpentAI/SerpentAI/wiki/Defining-Screen-Regions

x-window screen region selection
    Xlib Pointer Grabbing
         XGrabKeyboard  XGrabPointer
         region pointer grabbing
https://tronche.com/gui/x/xlib/input/XGrabKeyboard.html
 xlib xgrabpointer
x-window screen region selection
https://en.wikipedia.org/wiki/X_Window_System_protocols_and_architecture
https://en.wikipedia.org/wiki/X_Window_selection
https://en.wikipedia.org/wiki/Selection_(user_interface)

https://github.com/search?q=x-window+screen+region+selection+language%3AC++path%3A%2F%5EPsychSourceGL%5C%2FSource%5C%2FLinux%5C%2FScreen%5C%2F%2F&type=code

https://hackage.haskell.org/
https://github.com/c-koi/libboard
https://www.freebsdsoftware.org/graphics/
https://github.com/FreeCAD/FreeCAD/tree/b239797b3e4d2c5fdbc653ae5c150309a73b4474/src/3rdParty/libkdtree/kdtree%2B%2B
Blend2D  vector graphics libraries Grab Cursor screen region selection Pointer Grabbing vector graphics grabbing
repo:inanevin/LinaVG Cursor
https://github.com/search?q=repo%3Ainanevin%2FLinaVG+Cursor+&type=code

RectInRegion  判斷指定矩形的任何部分是否在區域的界限內。
https://learn.microsoft.com/zh-tw/windows/win32/api/wingdi/nf-wingdi-rectinregion
https://github.com/MicrosoftDocs/win32/blob/docs/desktop-src/gdi/region-functions.md
BOOL WINAPI RectInRegion( HRGN hrgn, const RECT *rect )
https://learn.microsoft.com/zh-tw/windows/win32/gdi/region-functions
https://learn.microsoft.com/zh-tw/windows/win32/api/wingdi/nf-wingdi-selectobject

OBJ_REGION
https://microsoft.github.io/windows-docs-rs/doc/windows/Win32/Graphics/Gdi/constant.OBJ_REGION.html
https://learn.microsoft.com/zh-tw/windows/win32/api/wingdi/nf-wingdi-getobjecttype
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-getwindowrgn
https://github.com/Guy1524/wine/blob/easy-anti-cheat/dlls/gdi32/region.c#L673
WINEREGION gdi

mouse cursor movements showing a trail of cursors cursor trail tracking animated cursor effects

 mouse cursor movements  showing a trail of cursors
cursor trail tracking animated cursor effects
8 CSS & JavaScript Snippets for Creating Unique Cursor Effects
https://speckyboy.com/css-javascript-cursor-effects/
https://onextrapixel.com/20-codepen-solutions-for-awesome-mouse-effects/
20 Codepen Solutions for Awesome Mouse Effects
https://codemyui.com/rainbow-mouse-trail/

delphi controls setwindowrgn windows api "rotary" image animated border size window SetRectEmpty SetWindowRgn SubtractRect TabbedTextOutA TabbedTextOutW

https://stackoverflow.com/questions/5160151/how-can-i-control-the-border-size-of-a-window
https://stackoverflow.com/questions/8972761/delphi-cutting-glass
https://stackoverflow.com/questions/11675374/how-to-make-tframe-with-rounded-corners
https://stackoverflow.com/questions/5755719/rounded-and-titled-tpanel-in-delphi-7

https://github.com/juliomar/awesome-delphi/tree/master#graphic

AggPas
http://www.crossgl.com/aggpas/documentation/index.html
AggPas - Delphi VCL API High Fidelity 2D Graphics
Object Pascal port of a High Quality Rendering Engine for C++ (D2009 & D2010) of AggPas library AggPas is an Object Pascal native port of the Anti-Grain Geometry library - AGG, originally

Graphics32
https://github.com › graphics32
Graphics32 is a graphics library for Delphi and Lazarus. Optimized for 32-bit pixel formats, it provides fast operations with pixels and graphic primitives

Image32
Image32 - A 2D graphics library written in Delphi Pascal
https://github.com › AngusJohnson › I...image32 delphi ( github.com)
Image32 is a comprehensive 2D graphics library written entirely in Delphi Pascal, and without dependencies on other libraries.

https://stackoverflow.com/questions/29778156/graphics32-layer-rotation
https://www.codeproject.com/articles/17245/runtime-control-resizer
https://github.com/bakasurarce/tsizectrl 

A Collection of Delphi/Lazarus Tips & Tricks
University of Tartu https://kodu.ut.ee › ~kiisk › Delphi-tips-tricks Show controls' hints on statusbar SetWindowRgn(Handle, rgn, TRUE) Show/hide titlebar of a form uses. Forms, Windows
https://kodu.ut.ee/~kiisk/Delphi-tips-tricks.pdf

https://hwb.com/gruhn/programming/tutorial/clear.html
Gruhn's Transparent Delphi App
https://stackoverflow.com/questions/53887931/how-make-the-same-hole-in-two-forms-on-remote-screen-client-side-based-on-ar
https://stackoverflow.com/questions/11692094/how-to-draw-extra-stuff-on-a-custom-component-after-creation-at-dt-rt
http://melander.dk/articles/alphasplash/
Alpha Blended Splash Screen in Delphi - Part 1 | MelanderBlog
https://stackoverflow.com/questions/11692094/how-to-draw-extra-stuff-on-a-custom-component-after-creation-at-dt-rt

delphi Windows Animation Library  AniVCL
Windows Animation Library for Delphi
http://www.bilsen.com/windowsanimation/
https://github.com/tonghoangvu/AniVCL
GitHub - tonghoangvu/AniVCL: Animation library for Delphi VCL
https://torry.net/components/effects-and-multimedia/animation/
https://www.delphipower.xyz/graphics/the_animate_control.html
AnimationLab VCL
WladiD/AnyiQuack Animation framework
Skia4Delphi
Fearless Cross-Platform Development with Delphi: Expand your Delphi skills

Windows Animation Overview - Win32 apps
Microsoft Learn https://learn.microsoft.com › uianimation Windows Animation API is a single-threaded COM-based API that provides the following features for developers: An animation manager object Basic Concepts · ‎Components of Windows...

AnimateWindow function (winuser.h) - Win32 apps
Microsoft Learn https://learn.microsoft.com › win32 › api Enables you to produce special effects when showing or hiding windows. There are four types of animation: roll, slide, collapse or expand, and Syntax Parameters

https://github.com/MicrosoftDocs/win32/blob/docs/desktop-src/UIAnimation/windows-animation-samples.md
windows-animation-samples.md - MicrosoftDocs/win32 GitHub https://github.com › docs › UIAnimation Shows how to use Windows Animation with your own Custom Interpolator, with Direct2D used for rendering. Grid Layout Sample, Shows how to use Windows Animation, ...

https://learn.microsoft.com/en-us/windows/win32/uianimation/scenic-animation-api-overview
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-animatewindow

delphi windows api animated ui_animation_storyboard_status windows animation library for delphi

https://stackoverflow.com/questions/3394289/recommendations-for-a-docking-library-for-delphi-cbuilder
Recommendations for a docking library for Delphi / C++Builder? - Stack Overflow

https://www.3delite.hu/Object%20Pascal%20Developer%20Resources/filesystemdialogs.html
Delphi, C++, VB Filesystem Dialogs Library - Enhanced open file dialog & folder dialog component, file browser component

Raize components  RzComps RzComps images  Gradient RzComps images  Gradient
https://github.com/liuhouer/ClockTool/blob/master/RzAboutEditor.pas
https://github.com/liuhouer/ClockTool/blob/master/RzGrafx.pas
https://stackoverflow.com/questions/7265416/delphi-sliding-animated-panel
animation - Delphi: sliding (animated) panel - Stack Overflow
https://stackoverflow.com/questions/7265416/delphi-sliding-animated-panel
https://github.com/NLDelphi/NLDSideBar

Window Content Size Avail Content Region GetContentRegionAvail Content Region x window system device context mouse CursorPosition position calculation area GetContentRegionAvail

 https://www.codeproject.com/Articles/1944/Guide-to-WIN32-Regions

 https://github.com/ocornut/imgui/issues/1281

https://github.com/ocornut/imgui

Content Region shape windows MS rgn GetWindowRgn 

GetContentRegionMaxAbs / GetContentRegionAvail

https://github.com/ocornut/imgui/issues/1490

https://en.wikipedia.org/wiki/Pick%27s_theorem

shape Content Region Coordinates in the graph Position area Region Avail Using pgfplots to make economic graphs

shape Region graph area Region Avail make economic graphs Find Area Between Curves Graphs

How to Translate a Shape on a Coordinate Grid Using a Vector

whether two shapes overlap window MS  shapes are overlapping

https://www.geeksforgeeks.org/find-two-rectangles-overlap/

Retrieving Raw Mouse Input with GLFW

Graphics Windows GDI Region framergn FillRgn FrameRgn InvertRgn

 Graphics Windows GDI Region  framergn FillRgn FrameRgn InvertRgn

https://learn.microsoft.com/en-us/windows/win32/gdi/region-functions 

https://github.com/wuxc/pywin32doc/blob/master/md/win32gui.md

framergn regions setcapture windowfrompoint ptinregion offsetrgn

https://www.codeproject.com/Articles/1944/Guide-to-WIN32-Regions

https://learn.microsoft.com/en-us/windows/win32/gdi/combining-regions

https://www.codeproject.com/Articles/291/Creating-Holes-in-a-Window

https://www.flipcode.com/archives/Win32_Window_Skinning.shtml

 

WindowPicker - Pick any window using mouse and highlight window region

https://binaryworld.net/Main/CodeDetail.aspx?CodeId=3753

https://www.codeproject.com/Tips/127813/Using-SetCapture-and-ReleaseCapture-correctly-usua

http://www.flounder.com/setwindowrgn.htm

Custom VCL Control for getting window handles. (Spy++ style reticle) – Chapman World

https://chapmanworld.com/2018/10/04/custom-vcl-control-for-getting-window-handles-spy-style-reticle/

round rect Corner button rectangular region rounded corners Round Border CreateRoundRectRgn rectangular region rounded corners.

  round rect Corner button rectangular region rounded corners Round Border

The CreateRoundRectRgn function creates a rectangular region with rounded corners.
CreatePolyPolygonRgn
CreatePolygonRgn
CreateRectRgn
CreateRectRgnIndirect
DeleteObject
ExtCreateRegion
GetRegionData
Region Functions
Regions Overview
SelectObject

https://stackoverflow.com/questions/11675374/how-to-make-tframe-with-rounded-corners
https://github.com/pauloalvis/Delphi-PraButtonStyle

https://stackoverflow.com/questions/28486521/rounded-edges-in-button-c-sharp-winforms
https://stackoverflow.com/questions/21121968/how-do-i-create-button-with-rounded-corners-edges-on-winform-c
https://stackoverflow.com/questions/5755719/rounded-and-titled-tpanel-in-delphi-7
https://stackoverflow.com/questions/11675374/how-to-make-tframe-with-rounded-corners
https://stackoverflow.com/questions/42345751/firemonkey-hide-overflow-of-round-corners-using-stylebook
https://stackoverflow.com/questions/61159652/is-there-a-way-to-shape-a-button-around-its-picture-in-delphi

wincontrols round rect Corner CreateRoundRectRgn RoundedRadDropDownButton 

https://github.com/project-jedi/jvcl/blob/master/jvcl/run/JvThemes.pas

delphi form Transparent blur Msimg32.dll AlphaBlend

 https://stackoverflow.com/questions/5964701/how-to-draw-a-translucent-image-on-a-form

transparent background http://delphiexamples.com/forms/transpform.html

 https://sourceforge.net/projects/widget32/

https://parnassus.co/transparent-graphics-with-pure-gdi-part-2-and-introducing-the-ttransparentcanvas-class/

 Form com área transparente no Lazarus/Windows 

http://fanzinepas.blogspot.com/2012/06/form-com-area-transparente-no.html

THandle CreateRectRgn CreateRectRgn SetWindowRgn Winuser.h

https://www.codeguru.com/cplusplus/transparent-listbox/

https://stackoverflow.com/questions/48511634/partially-transparent-window-opengl-win32

 

winapi Transparent form layer GetMonitorInfo

https://www.experts-exchange.com/articles/1783/Win32-Semi-Transparent-Window.html

Layered Windows

https://docs.microsoft.com/en-us/previous-versions/ms997507(v=msdn.10)?redirectedfrom=MSDN

https://www.codeproject.com/Articles/1822/Per-Pixel-Alpha-Blend-in-C

 http://suyamasoft.blue.coocan.jp/ExcelVBA/Sample/SetLayeredWindowAttributes/index.html

http://suyamasoft.blue.coocan.jp/ExcelVBA/Sample/SetLayeredWindowAttributes/index.html

https://docs.microsoft.com/en-us/windows/win32/winauto/magapi/magapi-intro

Žarko Gajić gZoom – Delphi Implementation of the Missing Mode in Windows Magnifier

https://zarko-gajic.iz.hr/gzoom-delphi-implementation-of-the-missing-mode-in-windows-magnifier/

https://www.codeproject.com/Articles/5051/Various-methods-for-capturing-the-screen

https://www.codeproject.com/Articles/607288/Screenshot-using-the-Magnification-library

How can I change the background color of a button WinAPI C++

 Rectangles, Regions, and Clipping rectangular region CreateRoundRectRgn

 

https://miffyzzang.tistory.com/378
CreateWindow("button","",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON | BS_BITMAP | BS_OWNERDRAW,   100,100,70,30,hWnd,(HMENU)IDC_BUTTON, hInst,NULL);

Creating Owner-Drawn Controls - Windows Programming

BS_OWNERDRAW   SetButtonStyle SetWindowRgn

https://stackoverflow.com/questions/18745447/how-can-i-change-the-background-color-of-a-button-winapi-c

https://www.pablosoftwaresolutions.com/html/cimagebutton.html

#pragma comment( \
    linker, \
    "/manifestdependency:\"type='win32' \
    name='Microsoft.Windows.Common-Controls' \
    version='6.0.0.0' \
    processorArchitecture='*' \
    publicKeyToken='6595b64144ccf1df' \
    language='*'\"")
https://www.pablosoftwaresolutions.com/html/ccolorbutton.html

https://stackoverflow.com/questions/17678261/how-to-change-color-of-a-button-while-keeping-buttons-functions-in-win32
https://stackoverflow.com/questions/8695185/why-my-edit-control-looks-odd-in-my-win32-c-application-using-no-mfc

https://stackoverflow.com/questions/18745447/how-can-i-change-the-background-color-of-a-button-winapi-c

...show controls with rounded corners?

 https://www.swissdelphicenter.ch/en/showcode.php?id=921

 www.teamb.com

 Autor: P. Below
Homepage: http://www.teamb.com
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procedure MakeRounded(Control: TWinControl);
var
  R: TRect;
  Rgn: HRGN;
begin
  with Control do
  begin
    R := ClientRect;
    rgn := CreateRoundRectRgn(R.Left, R.Top, R.Right, R.Bottom, 20, 20);
    Perform(EM_GETRECT, 0, lParam(@r));
    InflateRect(r, - 5, - 5);
    Perform(EM_SETRECTNP, 0, lParam(@r));
    SetWindowRgn(Handle, rgn, True);
    Invalidate;
  end;
end;


procedure TForm1.Button1Click(Sender: TObject);
begin
  // TMemo:
  Memo1.BorderStyle := bsNone;
  MakeRounded(Memo1);
  // TEdit:
  Edit2.BorderStyle := bsNone;
  MakeRounded(Edit2);
  // TPanel:
  MakeRounded(Panel1);
  // TStaticText:
  MakeRounded(StaticText1);
  // TForm
  Form1.BorderStyle := bsNone;
  MakeRounded(Form1);
end;

Vcl.ExtCtrls.TShape corner size of RoundRect

FMX.StdCtrls.TCornerButton

https://stackoverflow.com/questions/11675374/how-to-make-tframe-with-rounded-corners

  TCustomRoundShape = class(TGraphicControl)

procedure TForm1.FormPaint(Sender: TObject);
const
  n = 50;
var
  Rgn: HRGN;
  x1,y1,x2,y2: Integer;
begin
  x1 := n;
  y1 := n div 2;
  x2 := ClientWidth - n;
  y2 := ClientHeight - n;
 
  Rgn := CreateRoundRectRgn(x1, y1, x2, y2, n, n);
 
  Canvas.Brush.Color := clSilver;
  Canvas.Brush.Style := bsCross;
  FillRgn(Canvas.Handle, Rgn, Canvas.Brush.Handle);
 
  Canvas.Brush.Color := clRed;
  Canvas.Brush.Style := bsSolid;
  FrameRgn(Canvas.Handle, Rgn, Canvas.Brush.Handle, 2, 2);

  DeleteObject(Rgn);
end;

 https://stackoverflow.com/questions/11675374/how-to-make-tframe-with-rounded-corners
https://stackoverflow.com/questions/5755719/rounded-and-titled-tpanel-in-delphi-7
https://stackoverflow.com/questions/32987649/how-to-create-a-user-control-with-rounded-corners

...create a form with rounded corners?
Autor: Horst Kniebusch
Homepage: http://members.tripod.de/Kniebusch
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{
  Die CreateRoundRectRgn lässt eine Form mit abgerundeten Ecken erscheinen.

  The CreateRoundRectRgn function creates a rectangular
  region with rounded corners
}

procedure TForm1.FormCreate(Sender: TObject);
var
  rgn: HRGN;
begin
  Form1.Borderstyle := bsNone;
  rgn := CreateRoundRectRgn(0,// x-coordinate of the region's upper-left corner
    0,            // y-coordinate of the region's upper-left corner
    ClientWidth,  // x-coordinate of the region's lower-right corner
    ClientHeight, // y-coordinate of the region's lower-right corner
    40,           // height of ellipse for rounded corners
    40);          // width of ellipse for rounded corners
  SetWindowRgn(Handle, rgn, True);
end


{ The CreatePolygonRgn function creates a polygonal region. }


procedure TForm1.FormCreate(Sender: TObject);
const
  C = 20;
var
  Points: array [0..7] of TPoint;
  h, w: Integer;
begin
  h := Form1.Height;
  w := Form1.Width;
  Points[0].X := C;     Points[0].Y := 0;
  Points[1].X := 0;     Points[1].Y := C;
  Points[2].X := 0;     Points[2].Y := h - c;
  Points[3].X := C;     Points[3].Y := h;

  Points[4].X := w - c; Points[4].Y := h;
  Points[5].X := w;     Points[5].Y := h - c;

  Points[6].X := w;     Points[6].Y := C;
  Points[7].X := w - C; Points[7].Y := 0;

  SetWindowRgn(Form1.Handle, CreatePolygonRgn(Points, 8, WINDING), True);
end;