导出 DWG/DXF 图纸和布局到指定大小

导出模型和所有布局为 A4 PDF 大小

Aspose.CAD API 允许您将 DWG/DXF 文件的所有图纸导出为指定的物理 PDF 大小。

以下示例代码设置 CadRasterizationOptions 对象的大小以实现所需的 PDF 大小。 A4 纸张的大小为 210x297 毫米或 8.27x11.69 英寸，这些值在代码中使用。

bool currentUnitIsMetric = false; 
double currentUnitCoefficient = 1.0; 
DefineUnitSystem(cadImage.UnitType, out currentUnitIsMetric, out currentUnitCoefficient);

if (currentUnitIsMetric) 
{ 
double metersCoeff = 1 / 1000.0;
double scaleFactor = metersCoeff / currentUnitCoefficient;
rasterizationOptions.PageWidth = (float)(210 * scaleFactor);
rasterizationOptions.PageHeight = (float)(297 * scaleFactor);
rasterizationOptions.UnitType = UnitType.Millimeter;
} 
else 
{ 
rasterizationOptions.PageWidth = (float)(8.27f / currentUnitCoefficient); 
rasterizationOptions.PageHeight = (float)(11.69f / currentUnitCoefficient); 
rasterizationOptions.UnitType = UnitType.Inch; 
}

private static void DefineUnitSystem(UnitType unitType, out bool isMetric, out double coefficient) 
{
isMetric = false; 
coefficient = 1.0;

switch (unitType)
{
	case UnitType.Parsec:
		coefficient = 3.0857 * 10000000000000000.0;
		isMetric = true;
		break;
	case UnitType.LightYear:
		coefficient = 9.4607 * 1000000000000000.0;
		isMetric = true;
		break;
	case UnitType.AstronomicalUnit:
		coefficient = 1.4960 * 100000000000.0;
		isMetric = true;
		break;
	case UnitType.Gigameter:
		coefficient = 1000000000.0;
		isMetric = true;
		break;
	case UnitType.Kilometer:
		coefficient = 1000.0;
		isMetric = true;
		break;
	case UnitType.Decameter:
		isMetric = true;
		coefficient = 10.0;
		break;
	case UnitType.Hectometer:
		isMetric = true;
		coefficient = 100.0;
		break;
	case UnitType.Meter:
		isMetric = true;
		coefficient = 1.0;
		break;
	case UnitType.Centimenter:
		isMetric = true;
		coefficient = 0.01;
		break;
	case UnitType.Decimeter:
		isMetric = true;
		coefficient = 0.1;
		break;
	case UnitType.Millimeter:
		isMetric = true;
		coefficient = 0.001;
		break;
	case UnitType.Micrometer:
		isMetric = true;
		coefficient = 0.000001;
		break;
	case UnitType.Nanometer:
		isMetric = true;
		coefficient = 0.000000001;
		break;
	case UnitType.Angstrom:
		isMetric = true;
		coefficient = 0.0000000001;
		break;
	case UnitType.Inch:
		coefficient = 1.0;
		break;
	case UnitType.MicroInch:
		coefficient = 0.000001;
		break;
	case UnitType.Mil:
		coefficient = 0.001;
		break;
	case UnitType.Foot:
		coefficient = 12.0;
		break;
	case UnitType.Yard:
		coefficient = 36.0;
		break;
	case UnitType.Mile:
		coefficient = 63360.0;
		break;
}
}

以不同大小将 CAD 布局导出为 PDF

有时需要将布局导出为其物理大小。下面的示例演示了将图纸导出为多页 PDF，其中每个带有布局内容的页面都有其自己的物理 PDF 大小。此示例使用 LayoutPageSizes 属性。

using (CadImage cadImage = (CadImage)Image.Load(fileName))
{
	CadRasterizationOptions rasterizationOptions = new CadRasterizationOptions();

	foreach (CadLayout layout in cadImage.Layouts.Values)
	{
		if (layout.LayoutName == "Model") continue;

		SizeF pageSize = GetPageSizeFromLayout(layout);
		rasterizationOptions.LayoutPageSizes.Add(layout.LayoutName, pageSize);
	}

	PdfOptions pdfOptions = new PdfOptions();
	pdfOptions.VectorRasterizationOptions = rasterizationOptions;
	cadImage.Save(outPath, pdfOptions);
}
			
private static SizeF GetPageSizeFromLayout(CadLayout layout)
{
	var isLandscape = IsLayoutLandscape(layout);

	float pageWidth;
	float pageHeight;

	if (layout.PlotPaperUnits == CadPlotPaperUnits.PlotInInches)
	{
		pageWidth = (float)MillimetersToInches(layout.PlotPaperSize.Width);
		pageHeight = (float)MillimetersToInches(layout.PlotPaperSize.Height);
	}
	else
	{
		pageWidth = (float)layout.PlotPaperSize.Width;
		pageHeight = (float)layout.PlotPaperSize.Height;
	}

	if (isLandscape)
	{
		return new SizeF(pageHeight, pageWidth);
	}
	else
	{
		return new SizeF(pageWidth, pageHeight);
	}
}

private static bool IsLayoutLandscape(CadLayout layout)
{
	return layout.PlotRotation == CadPlotRotation.Clockwise90Degrees || layout.PlotRotation == CadPlotRotation.Counterclockwise90Degrees;
}

private static double MillimetersToInches(double millimeters)
{
	const double MillimetersToInchesFactor = 0.0393701;
	return millimeters * MillimetersToInchesFactor;
}