ImageEn, unit imageenview |
|
TImageEnView.YScr2Bmp
Declaration
function YScr2Bmp(y: integer; CurrentLayer: Boolean = False): integer;
Description
The XScr2Bmp and
YScr2Bmp methods convert a window coordinate to the corresponding bitmap coordinate (considering
Zoom and
ViewX,
ViewY status).
y is a window coordinate.
If
CurrentLayer is true, then the result will be a coordinate relative to the
current layer. If false, it will be a coordinate relative to the background layer (layer 0).
Note:
◼The result may be negative or greater than the bitmap height if
y is beyond the displayed image's boundaries
◼To convert a coordinate of a non-current layer, use TImageEnView.Layers[].
ConvYScr2Bmp◼The screen value is relative to the control, i.e. as if the TImageEnView is positioned at 0,0 on the active screen
◼If you are using the
PdfViewer in
ShowAllPages mode, the result is given as a position in within the
active page (See:
PageOrigin)
| Demos\Other\PixelView\PixelView.dpr |
// X and Y are MOUSE coordinates
bx := ImageEnView1.XScr2Bmp( X, False );
by := ImageEnView1.YScr2Bmp( Y, False );
// ...now bx and by are Bitmap coordinates (of ImageEnView1.IEBitmap)
// But they may be out of the bitmap range, so check them...
if ( bx >= 0 ) and ( bx < ImageEnView1.IEBitmap.Width ) and ( by >= 0 ) and ( by < ImageEnView1.IEBitmap.Height ) then
begin
ImageEnView1.IEBitmap.Pixels[ bx, by ] := TColor2TRGB( clRed );
ImageEnView1.Update();
end;
// Allow images from a TImageEnMView to be dropped onto a TImageEnView as layers
procedure TMainForm.ImageEnMView1MouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer);
begin
if ssLeft in Shift then
begin
(Sender as TImageEnMView).MouseInteract := [];
(Sender as TImageEnMView).IEBeginDrag(False, -1);
end;
end;
procedure TMainForm.ImageEnMView1EndDrag(Sender, Target: TObject; X, Y: Integer);
begin
(Sender as TImageEnMView).IEEndDrag();
(Sender as TImageEnMView).MouseInteract := [mmiSelect];
end;
procedure TMainForm.ImageEnView1DragOver(Sender, Source: TObject; X, Y: Integer; State: TDragState; var Accept: Boolean);
begin
if (Source is TImageEnMView) then
Accept := True;
end;
procedure TMainForm.ImageEnView1DragDrop(Sender, Source: TObject; X, Y: Integer);
var
bmp: TIEBitmap;
idx: Integer;
begin
idx := TImageEnMView(Source).SelectedImage;
if idx >= 0 then
begin
bmp := ImageEnMView1.GetTIEBitmap( idx );
ImageEnView1.LayersAdd( bmp );
ImageEnView1.CurrentLayer.PosX := ImageEnView1.XScr2Bmp( X );
ImageEnView1.CurrentLayer.PosY := ImageEnView1.YScr2Bmp( Y );
TImageEnMView(Source).ReleaseBitmap(idx, False);
ImageEnView1.Update();
end;
end;
// At TTimer interval, paint the pixel at the cursor position white
// Note: Example only. MouseMove event would be better for this
procedure TForm1.Timer1Timer(Sender: TObject);
var
Pos: TPoint;
begin
// Get pos of cursor on screen
GetCursorPos(Pos);
// Convert it to position of the TImageEnView
Pos := ImageEnView1.ScreenToClient(Pos);
// Convert it to a bitmap value
Pos.X := ImageEnView1.XScr2Bmp(Pos.X);
Pos.Y := ImageEnView1.YScr2Bmp(Pos.Y);
// Paint the pixel
if ( Pos.X >= 0 ) and ( Pos.X < ImageEnView1.IEBitmap.Width ) and
( Pos.Y >= 0 ) and ( Pos.Y < ImageEnView1.IEBitmap.Height ) then
begin
ImageEnView1.IEBitmap.Pixels[ Pos.X, Pos.Y ] := TColor2TRGB( clWhite );
ImageEnView1.Update();
end;
end;
// Insert text when user clicks on control
procedure Tfmain.ImageEnView1MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
mx, my: Integer;
begin
mx := ImageEnView1.XScr2Bmp( x );
my := ImageEnView1.XScr2Bmp( y );
ImageEnView1.LayersAdd( ielkText, mx, my );
TIETextLayer( ImageEnView1.CurrentLayer ).Text := format( 'Clicked at image pos: %d,%d', [ mx, my ]);
TIETextLayer( ImageEnView1.CurrentLayer ).SizeToText();
ImageEnView1.Update();
end;
See Also
◼XScr2Bmp◼XBmp2Scr◼YBmp2Scr◼VisibleBitmapRect