我来了,刚做好,一定可以用的。var i, j: integer; dct: TRect; begin j:=width; for i:=200 downto 0 do begin canvas.Brush.Color:=RGB(0, i, 255); Dct:=Rect(0, i, j, (i+1)*2); canvas.FillRect(Dct); end; canvas.Font.Size:=28; canvas.Font.Name:='隶书'; canvas.TextOut(100, 20, '成功!'); end;
Delphi之未经证实的葵花宝典2.7 的图像处理部分有一个颜色渐变文章,效果不错,速度很快
To: findcsdn(findcsdn) 你那个什么葵花宝典在什么地方?
{ blue to black } procedure TCyan.FormPaint(Sender: TObject); var i: word; c, y: real; begin c := ClientHeight/256; y := 0; for i := 255 downto 0 do begin canvas.Brush.Color := i * $10000; canvas.FillRect(rect(0, round(y), ClientWidth, round(y + c))); y := y + c; end; end;procedure TCyan.FormResize(Sender: TObject); begin FormPaint; end;
to: gototop99(巴蒂) ,你给我的那段代码和我自己写的代码一样的糟糕. 不过还是要谢谢你.
ACanvas:画布 AClipRect:区域 FromPoint:开始点 FromColor:开始颜色 ToPoint: 结束点 ToColor:结束颜色function SSDrawGradient(ACanvas: TCanvas; AClipRect: TRect; FromPoint, ToPoint: TPoint; FromColor, ToColor: TColor): Boolean; type TSSGradientDirection=(gdEast, gdWest, gdNorth, gdSouth, gdOther); var buf:TBitmap; w,h,y,x,XOffset,ir,ig,ib,pw,ph:Integer; c1, c2: TColor; r1,g1,b1,r2,g2,b2,br,bg,bb,rmax,rmin,gmax,gmin,bmax,bmin: Byte; kx,ky,kx0,ky0,rx0,gx0,bx0,r0,g0,b0,drx,dry,dgx,dgy,dbx,dby,dr,dg,db: Double; P : PByteArray; function GetStep(V1, V2, V3:Integer): Double; begin if V2=V1 then Result:=0 else Result:=V3/(V2-V1); end;begin Result:=False; if (FromPoint.Y=ToPoint.Y)and(FromPoint.X=ToPoint.X) then Exit; buf:=TBitmap.Create; try //初始化缓冲区 buf.PixelFormat:=pf24bit; w:=WidthOfRect(AClipRect); buf.Width:=w; h:=HeightOfRect(AClipRect); buf.Height:=h; //为了防止运算溢出而设的检查 if (w>Screen.Width)or(h>Screen.Height) then Exit; //读取渐变起点和终点的RGB值 c1:=ColorToRGB(FromColor); c2:=ColorToRGB(ToColor); r1:=GetRValue(c1); g1:=GetGValue(c1); b1:=GetBValue(c1); r2:=GetRValue(c2); g2:=GetGValue(c2); b2:=GetBValue(c2); if r1>r2 then begin rmin:=r2; rmax:=r1 end else begin rmin:=r1; rmax:=r2 end; if g1>g2 then begin gmin:=g2; gmax:=g1 end else begin gmin:=g1; gmax:=g2 end; if b1>b2 then begin bmin:=b2; bmax:=b1 end else begin bmin:=b1; bmax:=b2 end; pw:=Abs(ToPoint.X-FromPoint.X); ph:=Abs(ToPoint.Y-FromPoint.Y); kx:=pw/Sqrt(ph*ph+pw*pw); ky:=ph/Sqrt(ph*ph+pw*pw);
//计算出RGB值相对于XY轴的线性变化系数 drx:=GetStep(AClipRect.Left, AClipRect.Right, Round((r2-r1)*kx)); dry:=GetStep(AClipRect.Top, AClipRect.Bottom, Round((r2-r1)*ky)); dgx:=GetStep(AClipRect.Left, AClipRect.Right, Round((g2-g1)*kx)); dgy:=GetStep(AClipRect.Top, AClipRect.Bottom, Round((g2-g1)*ky)); dbx:=GetStep(AClipRect.Left, AClipRect.Right, Round((b2-b1)*kx)); dby:=GetStep(AClipRect.Top, AClipRect.Bottom, Round((b2-b1)*ky)); //计算出矩形左上角的RGB值,备用 kx0:=GetStep(FromPoint.X, ToPoint.X, FromPoint.X); ky0:=GetStep(FromPoint.Y, ToPoint.Y, FromPoint.Y); r0:=r1+(kx0+ky0)*r2; g0:=g1+(kx0+ky0)*g2; b0:=b1+(kx0+ky0)*b2; //这三个变量是每个扫描线的第一个点的RGB值 rx0:=r0; gx0:=g0; bx0:=b0; for y:=0 to h-1 do begin XOffset:=0; //dr意思是Double类型的红色值,其他类推 dr:=rx0; dg:=gx0; db:=bx0; P := buf.ScanLine[y]; for x:=0 to w-1 do begin //ir的意思是整型的红色值,其他类推 //之所以要先转成整型,是因为我觉得整型的比较也许会比浮点快一点 //反正都要三次Round的,不如早做…… ir:=Round(dr); ig:=Round(dg); ib:=Round(db); //br的意思是字节型的红色值 br:=Max(Min(rmax,ir),rmin); bg:=Max(Min(gmax,ig),gmin); bb:=Max(Min(bmax,ib),bmin); //按照偏移量设置RGB值 P[XOffset]:=bb; P[XOffset+1]:=bg; P[XOffset+2]:=br; if FromPoint.X<>ToPoint.X then begin //下一个像素的RGB值分别按照一定的系数递增 dr:=dr+drx; dg:=dg+dgx; db:=db+dbx; end; //因为我定义的P是字节型的数组,所以这里递增“3”,避免使用乘法 Inc(XOffset, 3); end; if FromPoint.Y<>ToPoint.Y then begin //按照RGB在Y轴方向上的变化规律计算下一行的第一个像素RGB值 rx0:=rx0+dry; gx0:=gx0+dgy; bx0:=bx0+dby; end; end; //将缓冲区复制到目标上 BitBlt(ACanvas.Handle, AClipRect.Left, AClipRect.Top, w, h, buf.Canvas.Handle, 0, 0, SRCCOPY); Result:=True; finally buf.Free; end; end
楼上的方法偶试过了,但是好像和我想象的效果差不少。 你的那几个函数我自己写了不知道是不是: function WidthOfRect(ARect: TRect): integer; begin Result := ARect.Right - ARect.Left + 1; end; function HeightOfRect(ARect: TRect): integer; begin Result := ARect.Bottom - ARect.Top + 1; end; function Max(A, B: byte): Byte; begin if A > B then Result := A else Result := b; end; function Min(A, B: byte): byte; begin if A < b then Result := a else Result := b; end;
用一个 api 函数 GradientFill 得出的渐变色和 windows 标题栏中的一模一样。
i, j: integer;
dct: TRect;
begin
j:=width;
for i:=200 downto 0 do
begin
canvas.Brush.Color:=RGB(0, i, 255);
Dct:=Rect(0, i, j, (i+1)*2);
canvas.FillRect(Dct);
end;
canvas.Font.Size:=28;
canvas.Font.Name:='隶书';
canvas.TextOut(100, 20, '成功!');
end;
的图像处理部分有一个颜色渐变文章,效果不错,速度很快
procedure TCyan.FormPaint(Sender: TObject);
var
i: word;
c, y: real;
begin
c := ClientHeight/256;
y := 0;
for i := 255 downto 0 do begin
canvas.Brush.Color := i * $10000;
canvas.FillRect(rect(0, round(y), ClientWidth, round(y + c)));
y := y + c;
end;
end;procedure TCyan.FormResize(Sender: TObject);
begin
FormPaint;
end;
不过还是要谢谢你.
FromPoint:开始点 FromColor:开始颜色
ToPoint: 结束点 ToColor:结束颜色function SSDrawGradient(ACanvas: TCanvas; AClipRect: TRect;
FromPoint, ToPoint: TPoint; FromColor, ToColor: TColor): Boolean;
type
TSSGradientDirection=(gdEast, gdWest, gdNorth, gdSouth, gdOther);
var
buf:TBitmap;
w,h,y,x,XOffset,ir,ig,ib,pw,ph:Integer;
c1, c2: TColor;
r1,g1,b1,r2,g2,b2,br,bg,bb,rmax,rmin,gmax,gmin,bmax,bmin: Byte;
kx,ky,kx0,ky0,rx0,gx0,bx0,r0,g0,b0,drx,dry,dgx,dgy,dbx,dby,dr,dg,db: Double;
P : PByteArray; function GetStep(V1, V2, V3:Integer): Double;
begin
if V2=V1 then Result:=0
else Result:=V3/(V2-V1);
end;begin
Result:=False;
if (FromPoint.Y=ToPoint.Y)and(FromPoint.X=ToPoint.X) then Exit;
buf:=TBitmap.Create;
try
//初始化缓冲区
buf.PixelFormat:=pf24bit;
w:=WidthOfRect(AClipRect);
buf.Width:=w;
h:=HeightOfRect(AClipRect);
buf.Height:=h;
//为了防止运算溢出而设的检查
if (w>Screen.Width)or(h>Screen.Height) then Exit; //读取渐变起点和终点的RGB值
c1:=ColorToRGB(FromColor);
c2:=ColorToRGB(ToColor);
r1:=GetRValue(c1);
g1:=GetGValue(c1);
b1:=GetBValue(c1);
r2:=GetRValue(c2);
g2:=GetGValue(c2);
b2:=GetBValue(c2);
if r1>r2 then begin rmin:=r2; rmax:=r1 end
else begin rmin:=r1; rmax:=r2 end;
if g1>g2 then begin gmin:=g2; gmax:=g1 end
else begin gmin:=g1; gmax:=g2 end;
if b1>b2 then begin bmin:=b2; bmax:=b1 end
else begin bmin:=b1; bmax:=b2 end;
pw:=Abs(ToPoint.X-FromPoint.X);
ph:=Abs(ToPoint.Y-FromPoint.Y);
kx:=pw/Sqrt(ph*ph+pw*pw);
ky:=ph/Sqrt(ph*ph+pw*pw);
//计算出RGB值相对于XY轴的线性变化系数
drx:=GetStep(AClipRect.Left, AClipRect.Right, Round((r2-r1)*kx));
dry:=GetStep(AClipRect.Top, AClipRect.Bottom, Round((r2-r1)*ky));
dgx:=GetStep(AClipRect.Left, AClipRect.Right, Round((g2-g1)*kx));
dgy:=GetStep(AClipRect.Top, AClipRect.Bottom, Round((g2-g1)*ky));
dbx:=GetStep(AClipRect.Left, AClipRect.Right, Round((b2-b1)*kx));
dby:=GetStep(AClipRect.Top, AClipRect.Bottom, Round((b2-b1)*ky)); //计算出矩形左上角的RGB值,备用
kx0:=GetStep(FromPoint.X, ToPoint.X, FromPoint.X);
ky0:=GetStep(FromPoint.Y, ToPoint.Y, FromPoint.Y);
r0:=r1+(kx0+ky0)*r2;
g0:=g1+(kx0+ky0)*g2;
b0:=b1+(kx0+ky0)*b2; //这三个变量是每个扫描线的第一个点的RGB值
rx0:=r0;
gx0:=g0;
bx0:=b0;
for y:=0 to h-1 do
begin
XOffset:=0;
//dr意思是Double类型的红色值,其他类推
dr:=rx0;
dg:=gx0;
db:=bx0;
P := buf.ScanLine[y];
for x:=0 to w-1 do
begin
//ir的意思是整型的红色值,其他类推
//之所以要先转成整型,是因为我觉得整型的比较也许会比浮点快一点
//反正都要三次Round的,不如早做……
ir:=Round(dr);
ig:=Round(dg);
ib:=Round(db);
//br的意思是字节型的红色值
br:=Max(Min(rmax,ir),rmin);
bg:=Max(Min(gmax,ig),gmin);
bb:=Max(Min(bmax,ib),bmin);
//按照偏移量设置RGB值
P[XOffset]:=bb;
P[XOffset+1]:=bg;
P[XOffset+2]:=br; if FromPoint.X<>ToPoint.X then
begin
//下一个像素的RGB值分别按照一定的系数递增
dr:=dr+drx;
dg:=dg+dgx;
db:=db+dbx;
end;
//因为我定义的P是字节型的数组,所以这里递增“3”,避免使用乘法
Inc(XOffset, 3);
end;
if FromPoint.Y<>ToPoint.Y then
begin
//按照RGB在Y轴方向上的变化规律计算下一行的第一个像素RGB值
rx0:=rx0+dry;
gx0:=gx0+dgy;
bx0:=bx0+dby;
end;
end;
//将缓冲区复制到目标上
BitBlt(ACanvas.Handle, AClipRect.Left, AClipRect.Top, w, h,
buf.Canvas.Handle, 0, 0, SRCCOPY);
Result:=True;
finally
buf.Free;
end;
end
你的那几个函数我自己写了不知道是不是:
function WidthOfRect(ARect: TRect): integer;
begin
Result := ARect.Right - ARect.Left + 1;
end;
function HeightOfRect(ARect: TRect): integer;
begin
Result := ARect.Bottom - ARect.Top + 1;
end;
function Max(A, B: byte): Byte;
begin
if A > B then
Result := A
else
Result := b;
end;
function Min(A, B: byte): byte;
begin
if A < b then
Result := a
else
Result := b;
end;