DocumentRenderToScale Method

Renders a document page into a Graphics object to a specified scale.

Namespace:  Aspose.Words
Assembly:  Aspose.Words (in Aspose.Words.dll) Version: 20.3
Syntax
public SizeF RenderToScale(
	int pageIndex,
	Graphics graphics,
	float x,
	float y,
	float scale
)

Parameters

pageIndex
Type: SystemInt32
The 0-based page index.
graphics
Type: System.DrawingGraphics
The object where to render to.
x
Type: SystemSingle
The X coordinate (in world units) of the top left corner of the rendered page.
y
Type: SystemSingle
The Y coordinate (in world units) of the top left corner of the rendered page.
scale
Type: SystemSingle
The scale for rendering the page (1.0 is 100%).

Return Value

Type: SizeF
The width and height (in world units) of the rendered page.
Examples
Renders individual pages to graphics to create one image with thumbnails of all pages.
// The user opens or builds a document
Document doc = new Document(MyDir + "Rendering.docx");

// This defines the number of columns to display the thumbnails in
const int thumbColumns = 2;

// Calculate the required number of rows for thumbnails
// We can now get the number of pages in the document
int thumbRows = Math.DivRem(doc.PageCount, thumbColumns, out int remainder);
if (remainder > 0)
    thumbRows++;

// Lets say I want thumbnails to be of this zoom
const float scale = 0.25f;

// For simplicity lets pretend all pages in the document are of the same size, 
// so we can use the size of the first page to calculate the size of the thumbnail
Size thumbSize = doc.GetPageInfo(0).GetSizeInPixels(scale, 96);

// Calculate the size of the image that will contain all the thumbnails
int imgWidth = thumbSize.Width * thumbColumns;
int imgHeight = thumbSize.Height * thumbRows;

using (Bitmap img = new Bitmap(imgWidth, imgHeight))
{
    // The user has to provides a Graphics object to draw on
    // The Graphics object can be created from a bitmap, from a metafile, printer or window
    using (Graphics gr = Graphics.FromImage(img))
    {
        gr.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;

        // Fill the "paper" with white, otherwise it will be transparent
        gr.FillRectangle(new SolidBrush(Color.White), 0, 0, imgWidth, imgHeight);

        for (int pageIndex = 0; pageIndex < doc.PageCount; pageIndex++)
        {
            int rowIdx = Math.DivRem(pageIndex, thumbColumns, out int columnIdx);

            // Specify where we want the thumbnail to appear
            float thumbLeft = columnIdx * thumbSize.Width;
            float thumbTop = rowIdx * thumbSize.Height;

            SizeF size = doc.RenderToScale(pageIndex, gr, thumbLeft, thumbTop, scale);

            // Draw the page rectangle
            gr.DrawRectangle(Pens.Black, thumbLeft, thumbTop, size.Width, size.Height);
        }

        img.Save(ArtifactsDir + "Rendering.Thumbnails.png");
    }
}
Examples
Renders individual pages to graphics to create one image with thumbnails of all pages (.NetStandard 2.0).
// The user opens or builds a document
Document doc = new Document(MyDir + "Rendering.docx");

// This defines the number of columns to display the thumbnails in
const int thumbColumns = 2;

// Calculate the required number of rows for thumbnails
// We can now get the number of pages in the document
int thumbRows = Math.DivRem(doc.PageCount, thumbColumns, out int remainder);
if (remainder > 0)
    thumbRows++;

// Lets say I want thumbnails to be of this zoom
const float scale = 0.25f;

// For simplicity lets pretend all pages in the document are of the same size, 
// so we can use the size of the first page to calculate the size of the thumbnail
Size thumbSize = doc.GetPageInfo(0).GetSizeInPixels(scale, 96);

// Calculate the size of the image that will contain all the thumbnails
int imgWidth = thumbSize.Width * thumbColumns;
int imgHeight = thumbSize.Height * thumbRows;

using (SKBitmap bitmap = new SKBitmap(imgWidth, imgHeight))
{
    // The user has to provides a Graphics object to draw on
    // The Graphics object can be created from a bitmap, from a metafile, printer or window
    using (SKCanvas canvas = new SKCanvas(bitmap))
    {
        // Fill the "paper" with white, otherwise it will be transparent
        canvas.Clear(SKColors.White);

        for (int pageIndex = 0; pageIndex < doc.PageCount; pageIndex++)
        {
            int rowIdx = Math.DivRem(pageIndex, thumbColumns, out int columnIdx);

            // Specify where we want the thumbnail to appear
            float thumbLeft = columnIdx * thumbSize.Width;
            float thumbTop = rowIdx * thumbSize.Height;

            SizeF size = doc.RenderToScale(pageIndex, canvas, thumbLeft, thumbTop, scale);

            // Draw the page rectangle
            SKRect rect = new SKRect(0, 0, size.Width, size.Height);
            rect.Offset(thumbLeft, thumbTop);
            canvas.DrawRect(rect, new SKPaint
            {
                Color = SKColors.Black,
                Style = SKPaintStyle.Stroke
            });
        }

        using (SKFileWStream fs = new SKFileWStream(ArtifactsDir + "Rendering.CreateThumbnailsNetStandard2.png"))
        {
            bitmap.PeekPixels().Encode(fs, SKEncodedImageFormat.Png, 100);
        }
    }
}
See Also