Ejemplo n.º 1
0
 // Render a cached bitmap to a drawing context.
 void RenderMapArea(DrawingContext dc, CachedMapArea mapArea)
 {
     dc.DrawImage(mapArea.bitmap, new Rect(mapArea.portion.X, mapArea.portion.Y,
                                                        mapArea.pixelSize * mapArea.bitmap.Width, mapArea.pixelSize * mapArea.bitmap.Height));
 }
Ejemplo n.º 2
0
        // Fill in the bitmap member of a cached map area with a bitmap, created from the current map.
        void CreateBitmap(CachedMapArea mapArea)
        {
            // Determine the size of the bitmap we need.
            int height = (int) Math.Ceiling(mapArea.portion.Height / mapArea.pixelSize);
            int width = (int) Math.Ceiling(mapArea.portion.Width / mapArea.pixelSize);

            // Create transformation matrix from map coords to the bitmap coords
            Matrix matrix = Matrix.Identity;
            matrix.ScalePrepend(1 / mapArea.pixelSize, 1 / mapArea.pixelSize);
            matrix.TranslatePrepend(- mapArea.portion.X, - mapArea.portion.Y);

            // Get the render options.
            RenderOptions renderOpts = new RenderOptions();
            renderOpts.usePatternBitmaps = false;
            renderOpts.minResolution = (float) mapArea.pixelSize;

            // Create a visual of the map, appropriately transformed
            DrawingVisual visual = new DrawingVisual();
            DrawingContext dc = visual.RenderOpen();
            dc.PushTransform(new MatrixTransform(matrix));
            using (map.Read())
                map.Draw(dc, mapArea.portion, renderOpts);
            dc.Close();

            // Draw it into a new bitmap.
            if (mapArea.bitmap != null && mapArea.bitmap.PixelWidth >= width && mapArea.bitmap.PixelHeight >= height)
                mapArea.bitmap.Clear();  // reuse the old bitmap again by clearing it.
            else
                mapArea.bitmap = new RenderTargetBitmap(width, height, 96.0, 96.0, PixelFormats.Pbgra32);
            mapArea.bitmap.Render(visual);

            // Mark as up to date.
            mapArea.isUpToDate = true;
        }