我想使用 TPathData 绘制形状并用任意颜色填充它们。我在 Button1Click 中使用以下代码,该代码是从 Embarcadero 文档中的示例中提取的:
procedure TformPathDrawing.Button1Click(Sender: TObject);
var path: TPathData;
begin
Image1.Bitmap.Canvas.Fill.Color := TAlphaColorRec.Blue;
path := TPathData.Create;
path.Data := 'M 01,00 L 02,01 L 01,02 L 00,01 L 01,00';
Image1.Bitmap.Clear ($FFFFFF);
Image1.Bitmap.Canvas.BeginScene;
Image1.Bitmap.Canvas.FillPath (path, 200);
Image1.Bitmap.Canvas.EndScene;
end;
当执行此代码时,正如预期的那样,会渲染一个菱形,但它不会用第一个命令中设置的颜色填充。有人知道出了什么问题吗?谢谢。
这是正确的代码。您可以在 FMX.Objects.pas 过程 TCustomPath.UpdateCurrent 等中找到其他详细信息;或者只是调试 TPath 可视组件。
{aPath - is vector path of image;
aStretch - how to draw vector data - true - stretch draw, false = fit to bitmap
aBitmap - must be created. In bitmap you should specify:
Width, Height, Bitmap.Canvas.Fill.Color, Bitmap.Canvas.Stroke.Color
and, if you need, another drawing stuff like Gradient, stroke thikness,
background texture) }
procedure TForm1.DrawVectorPath(const aPath: string; aBitmap: TBitmap; aStretch: boolean);
var
vPath: TPathData;
R: TRectF;
begin
Assert(aBitmap <> nil);
vPath := TPathData.Create;
try
vPath.Data := aPath;
aBitmap.Clear($FFFFFF);
if aStretch then
begin
R := vPath.GetBounds;
vPath.Translate(-R.Left, -R.Top);
vPath.Scale(aBitmap.Width / R.Width, aBitmap.Height / R.Height);
end
else // Fit image
begin
R := TRect.Create(0, 0, aBitmap.Width, aBitmap.Height);
vPath.FitToRect(R);
end;
aBitmap.Canvas.BeginScene;
aBitmap.Canvas.FillPath(vPath, 1);
aBitmap.Canvas.DrawPath(vPath, 1);
aBitmap.Canvas.EndScene;
finally
vPath.Free;
end;
end;
因为注释不能有代码(至少不能格式化)。这是我的代码,有效。
procedure TForm7.RadioButton6Click(Sender: TObject);
var path: TPathData;
begin
Image1.Bitmap.Canvas.Fill.Color := TAlphaColorRec.Blue;
Image1.Bitmap.Canvas.Stroke.Color := TAlphaColorRec.black;
path := TPathData.Create;
try
path.Data := 'M 01,00 L 20,01 L 10,20 L 00,10 L 01,00';
Image1.Bitmap.Clear ($FFFFFF);
Image1.Bitmap.Canvas.BeginScene;
Image1.Bitmap.Canvas.FillPath (path, 200);
Image1.Bitmap.Canvas.EndScene;
finally
path.Free;
end;
end;
请注意,描边颜色也已设置。这是我在这里能看出的唯一区别。
遵循有效的代码(就我而言):
procedure TformPathDrawing.Button1Click(Sender: TObject);
begin
Image1.Bitmap.Canvas.Fill.Color := TAlphaColorRec.Blue;
path.Clear;
path.Data := 'M 01,00 L 02,01 L 01,02 L 00,01 L 01,00';
Image1.Bitmap.Canvas.BeginScene;
Image1.Bitmap.Canvas.FillPath (path, 1);
Image1.Bitmap.Canvas.EndScene;
end;
在我的代码中,变量
path
是在绘画代码之外创建的。由于 path.Data;
是可加的,因此在添加当前 path.Data;
之前,必须放置 path.Clear;
语句,以清除点数组中剩余的内容。希望这对其他人有帮助。