在Delphi中如何使图像淡入淡出?
借花献佛:
unit drdc;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, ExtCtrls, StdCtrls;
type
TForm1 = class(TForm)
Button1: TButton;
Button2: TButton;
Image1: TImage;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R .DFM}
procedure TForm1.Button1Click(Sender: TObject);
var
x,y,i:integer;
Bitmap:TBitmap;
pixcolo:PByteArray;
begin
Bitmap:=TBitmap.Create;
//创建TBitMap实例
try
Bitmap.LoadFromFile
(c:\windows\clouds.bmp);
Bitmap.PixelFormat:=pf24bit;
for i:=0 to 255 do
begin
for y:=0 to Bitmap.Height-1 do
begin
pixcolo:=Bitmap.Scanline[y];
//扫描每行像素颜色
for x:=0 to ((Bitmap.Width3)-1) do
if pixcolo[x]>0 then pixcolo[x]:=(pixcolo[x]-1);
//递减颜色值,不同的递减值可改变不同的速度
end;
Image1.Canvas.Draw(0,0,Bitmap);
//画出图像
Application.ProcessMessages;
//系统做其他工作
end;
finally
Bitmap.free; //释放位图
end;
end;
procedure TForm1.Button2Click(Sender: TObject);
var
x,y,i,j:integer;
Bitmap1,Bitmap2:TBitmap;
pixcolo1,pixcolo2:PByteArray;
begin
Bitmap1:=TBitmap.Create;
Bitmap2:=TBitmap.Create;
try
Bitmap1.LoadFromFile(c:\windows\clouds.bmp);
//将同一幅图像装入两个TBitmap实例
Bitmap2.LoadFromFile(c:\windows\clouds.bmp);
Bitmap1.pixelFormat:=pf24bit;
Bitmap2.pixelFormat:=pf24bit;
for y:=0 to Bitmap2.height-1 do
begin
pixcolo2:=Bitmap2.Scanline[y];
for x:=0 to ((Bitmap2.Width3)-1) do
pixcolo2[x]:=0;
//先将要处理的图像的像素颜色值设为0
end;
for i:=0 to 255 do
begin
for y:=0 to Bitmap2.Height-1 do
begin
pixcolo2:=Bitmap2.Scanline[y];
pixcolo1:=Bitmap1.Scanline[y];
for x:=0 to ((Bitmap2.Width3)-1) do if pixcolo2[x]<pixcolo1[x] then pixcolo2[x]:=(pixcolo2[x]+1);
end;
//与原始图的像素颜色值比较,并递增其值直到与原始图相等
Image1.Canvas.Draw(0,0,Bitmap2);
Application.ProcessMessages;
end;
finally
Bitmap1.free
end;
end;
end.