Преобразование мировых координат + обрезка регионом.
Переделал примерчик из Demos GDI+
использовал указанную в посте картинку. (под именем 1.jpg)
| Код |
program GDITEST48;
uses
Windows,
Messages,
SysUtils,
GDIPAPI,
GDIPOBJ;
// One of the properties of the Graphics class is the clipping region.
// All drawing done by a given Graphics object is restricted to the clipping
// region of that Graphics object. You can set the clipping region by
// calling the SetClip method.
// The following example constructs a path that consists of a single polygon.
// Then the code constructs a region based on that path. The address of the
// region is passed to the SetClip method of a Graphics object, and then two
// strings are drawn.
Procedure OnPaint(DC: HDC);
var
graphics : TGPGraphics;
path: TGPGraphicsPath;
Pen: TGPPen;
region: TGPRegion;
bmp : TGPImage;
w, h : integer;
const
polyPoints : array[0..3] of TGPPoint =
((x: 90 ; y: 160 ),
(x: 250; y: 20 ),
(x: 410; y: 220 ),
(x: 250; y: 360));
begin
graphics := TGPGraphics.Create(DC);
path:= TGPGraphicsPath.Create;
path.AddPolygon(PGPPoint(@polyPoints), 4);
// Construct a region based on the path.
region := TGPRegion.Create(path);
// Draw the outline of the region.
pen:= TGPPen.Create(MakeColor(255, 0, 0, 0));
// Set the clipping region of the Graphics object.
graphics.RotateTransform(41);
graphics.TranslateTransform(0, -150);
graphics.DrawPath(pen, path);
graphics.SetClip(region);
// Draw some clipped strings.
bmp := TGPImage.Create('1.jpg');
w := bmp.GetWidth;
h := bmp.GetHeight;
graphics.DrawImage(bmp, 0, 0, w, h);
graphics.Free;
bmp.Free;
path.Free;
region.Free;
end;
function WndProc(Wnd : HWND; message : UINT; wParam : Integer; lParam: Integer) : Integer; stdcall;
var
Handle: HDC;
ps: PAINTSTRUCT;
begin
case message of
WM_PAINT:
begin
Handle := BeginPaint(Wnd, ps);
OnPaint(Handle);
EndPaint(Wnd, ps);
result := 0;
end;
WM_DESTROY:
begin
PostQuitMessage(0);
result := 0;
end;
else
result := DefWindowProc(Wnd, message, wParam, lParam);
end;
end;
var
hWnd : THandle;
Msg : TMsg;
wndClass : TWndClass;
begin
wndClass.style := CS_HREDRAW or CS_VREDRAW;
wndClass.lpfnWndProc := @WndProc;
wndClass.cbClsExtra := 0;
wndClass.cbWndExtra := 0;
wndClass.hInstance := hInstance;
wndClass.hIcon := LoadIcon(0, IDI_APPLICATION);
wndClass.hCursor := LoadCursor(0, IDC_ARROW);
wndClass.hbrBackground := HBRUSH(GetStockObject(WHITE_BRUSH));
wndClass.lpszMenuName := nil;
wndClass.lpszClassName := 'GettingStarted';
RegisterClass(wndClass);
hWnd := CreateWindow(
'GettingStarted', // window class name
'Clipping with a Region', // window caption
WS_OVERLAPPEDWINDOW, // window style
Integer(CW_USEDEFAULT), // initial x position
Integer(CW_USEDEFAULT), // initial y position
Integer(CW_USEDEFAULT), // initial x size
Integer(CW_USEDEFAULT), // initial y size
0, // parent window handle
0, // window menu handle
hInstance, // program instance handle
nil); // creation parameters
ShowWindow(hWnd, SW_SHOW);
UpdateWindow(hWnd);
while(GetMessage(msg, 0, 0, 0)) do
begin
TranslateMessage(msg);
DispatchMessage(msg);
end;
end.
|
|
