摘要：
//创建调色板函数、R、G、B颜色组件，0-1之间的值为1FUNCTIONMaxGradientPalette（CONSTRedFactor、GreenFactor、BlueFactor:Single）：hPalette；2VAR3i：整数；4逻辑调色板：TMaxLogPalette；5BEGIN6ASSERT（红色系数˂=1）；//值必须为0
//创建调色板函数,R,G,B颜色分量,0-1之间取值
1 FUNCTION MaxGradientPalette(CONST RedFactor, GreenFactor, BlueFactor: Single): hPalette;
2 VAR
3 i : INTEGER;
4 LogicalPalette: TMaxLogPalette;
5 BEGIN
6 ASSERT (RedFactor <= 1); // values must be 0 to 1
7 ASSERT (GreenFactor <= 1);
8 ASSERT (BlueFactor <= 1);
9
10 LogicalPalette.palVersion := PaletteVersion;
11 LogicalPalette.palNumEntries := 256;
12 FOR i := 0 TO 255 DO
13 BEGIN
14 LogicalPalette.palPalEntry[i].peRed := Round(i * RedFactor);
15 LogicalPalette.palPalEntry[i].peGreen := Round(i * GreenFactor);
16 LogicalPalette.palPalEntry[i].peBlue := Round(i * BlueFactor);
17 LogicalPalette.palPalEntry[i].peFlags := PC_RESERVED;
18 END;
19 RESULT := CreatePalette(pLogPalette(@LogicalPalette)^);
20 END;
21
2 VAR
3 i : INTEGER;
4 LogicalPalette: TMaxLogPalette;
5 BEGIN
6 ASSERT (RedFactor <= 1); // values must be 0 to 1
7 ASSERT (GreenFactor <= 1);
8 ASSERT (BlueFactor <= 1);
9
10 LogicalPalette.palVersion := PaletteVersion;
11 LogicalPalette.palNumEntries := 256;
12 FOR i := 0 TO 255 DO
13 BEGIN
14 LogicalPalette.palPalEntry[i].peRed := Round(i * RedFactor);
15 LogicalPalette.palPalEntry[i].peGreen := Round(i * GreenFactor);
16 LogicalPalette.palPalEntry[i].peBlue := Round(i * BlueFactor);
17 LogicalPalette.palPalEntry[i].peFlags := PC_RESERVED;
18 END;
19 RESULT := CreatePalette(pLogPalette(@LogicalPalette)^);
20 END;
21
创建使用调色板的位图
1 procedure GradientBitmap(var ShowBitMap:TBitmap;CONST RedFactor, GreenFactor, BlueFactor: Single);
2 CONST
3 BitmapSize = 256;
4 VAR
5 i : INTEGER;
6 index : INTEGER;
7 j : INTEGER;
8 Row : pByteArray;
9 begin
10 ShowBitMap.PixelFormat := pf8bit;
11 ShowBitMap.Height := BitmapSize;
12 ShowBitMap.Width := BitmapSize;
13 // 1. Create palette first.
14 ShowBitMap.Palette:= MaxGradientPalette(RedFactor, GreenFactor, BlueFactor);
15
16 // 2. Assign Scanline value;
17 FOR j := 0 TO BitmapSize-1 DO
18 BEGIN
19 Row := ShowBitMap.Scanline[j];
20 FOR i := 0 TO BitmapSize-1 DO
21 BEGIN
22 index := (i+j) DIV 2;
23 Row[i] := index;
24 END
25 END;
26 end;
27
2 CONST
3 BitmapSize = 256;
4 VAR
5 i : INTEGER;
6 index : INTEGER;
7 j : INTEGER;
8 Row : pByteArray;
9 begin
10 ShowBitMap.PixelFormat := pf8bit;
11 ShowBitMap.Height := BitmapSize;
12 ShowBitMap.Width := BitmapSize;
13 // 1. Create palette first.
14 ShowBitMap.Palette:= MaxGradientPalette(RedFactor, GreenFactor, BlueFactor);
15
16 // 2. Assign Scanline value;
17 FOR j := 0 TO BitmapSize-1 DO
18 BEGIN
19 Row := ShowBitMap.Scanline[j];
20 FOR i := 0 TO BitmapSize-1 DO
21 BEGIN
22 index := (i+j) DIV 2;
23 Row[i] := index;
24 END
25 END;
26 end;
27
使用调色板位图,显示在Picture上面
1 procedure TFormPf8bit.Button4Click(Sender: TObject);
2 var
3 bitmap1:TBitmap;
4 begin
5 bitmap1:=TBitmap.Create;
6 GradientBitmap( bitmap1,0.5,0.2,1.0);
7 ImageShow.Picture.Graphic:=bitmap1;
8 bitmap1.Free;
9 end;
10
2 var
3 bitmap1:TBitmap;
4 begin
5 bitmap1:=TBitmap.Create;
6 GradientBitmap( bitmap1,0.5,0.2,1.0);
7 ImageShow.Picture.Graphic:=bitmap1;
8 bitmap1.Free;
9 end;
10