再学 GDI+[94]: TGPImage(14) - 增减图像的红、绿、蓝三色的成分

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ComCtrls;

type
TForm1 = class(TForm)
TrackBar1: TTrackBar;
TrackBar2: TTrackBar;
TrackBar3: TTrackBar;
Label1: TLabel;
Label2: TLabel;
Label3: TLabel;
Button1: TButton;
procedure FormPaint(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
procedure TrackBar1Change(Sender: TObject);
procedure TrackBar2Change(Sender: TObject);
procedure TrackBar3Change(Sender: TObject);
procedure Button1Click(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

uses GDIPOBJ, GDIPAPI;

var
img: TGPImage;
var
ColorMatrix: TColorMatrix = (
(1.0, 0.0, 0.0, 0.0, 0.0),
(0.0, 1.0, 0.0, 0.0, 0.0),
(0.0, 0.0, 1.0, 0.0, 0.0),
(0.0, 0.0, 0.0, 1.0, 0.0),
(0.0, 0.0, 0.0, 0.0, 1.0));

procedure TForm1.FormCreate(Sender: TObject);
begin
img := TGPImage.Create('c:\temp\test.png');

TrackBar1.Height := 23;
TrackBar1.ShowSelRange := False;
TrackBar1.Min := -100;
TrackBar1.Max := 100;
TrackBar1.Position := 0;

TrackBar2.Height := 23;
TrackBar2.ShowSelRange := False;
TrackBar2.Min := -100;
TrackBar2.Max := 100;
TrackBar2.Position := 0;

TrackBar3.Height := 23;
TrackBar3.ShowSelRange := False;
TrackBar3.Min := -100;
TrackBar3.Max := 100;
TrackBar3.Position := 0;

DoubleBuffered := True;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
img.Free;
end;

procedure TForm1.FormPaint(Sender: TObject);
var
g: TGPGraphics;
ImageAttributes: TGPImageAttributes;
begin
g := TGPGraphics.Create(Canvas.Handle);

ImageAttributes := TGPImageAttributes.Create;
ColorMatrix[4,0] := TrackBar1.Position / 100; {增减红色}
ColorMatrix[4,1] := TrackBar2.Position / 100; {增减绿色}
ColorMatrix[4,2] := TrackBar3.Position / 100; {增减蓝色}

ImageAttributes.SetColorMatrix(ColorMatrix);

g.DrawImage(img,                                           {要绘制的图像}
MakeRect(10, 10, img.GetWidth, img.GetHeight), {图像将放缩以适合此矩形}
0, 0,                                          {绘图位置}
img.GetWidth, img.GetHeight,                   {大小}
UnitPixel,                                     {单位}
ImageAttributes                                {图像属性}
);

ImageAttributes.Free;
g.Free;
end;

procedure TForm1.TrackBar1Change(Sender: TObject);
begin
Repaint;
end;

procedure TForm1.TrackBar2Change(Sender: TObject);
begin
Repaint;
end;

procedure TForm1.TrackBar3Change(Sender: TObject);
begin
Repaint;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
TrackBar1.Position := 0;
TrackBar2.Position := 0;
TrackBar3.Position := 0;
Repaint;
end;

end.

object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 291
ClientWidth = 219
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'Tahoma'
Font.Style = []
OldCreateOrder = False
Position = poDesktopCenter
OnCreate = FormCreate
OnDestroy = FormDestroy
OnPaint = FormPaint
PixelsPerInch = 96
TextHeight = 13
object Label1: TLabel
Left = 12
Top = 188
Width = 24
Height = 13
Caption = #32418#33394
end
object Label2: TLabel
Left = 12
Top = 212
Width = 24
Height = 13
Caption = #32511#33394
end
object Label3: TLabel
Left = 12
Top = 234
Width = 24
Height = 13
Caption = #34013#33394
end
object TrackBar1: TTrackBar
Left = 39
Top = 185
Width = 172
Height = 45
TabOrder = 0
OnChange = TrackBar1Change
end
object TrackBar2: TTrackBar
Left = 39
Top = 207
Width = 172
Height = 45
TabOrder = 1
OnChange = TrackBar2Change
end
object TrackBar3: TTrackBar
Left = 39
Top = 229
Width = 172
Height = 45
TabOrder = 2
OnChange = TrackBar3Change
end
object Button1: TButton
Left = 88
Top = 258
Width = 75
Height = 25
Caption = #24674#22797#40664#35748
TabOrder = 3
OnClick = Button1Click
end
end