How do you draw a Direct2D canvas on to a TcxImage Canvas?

I have an Direct2D demo that creates a GridPatternBitmapBrush then draws the grid pattern on a TForm in a paint method. How do you get the Direct2D GridPatternBitmapBrush to appear on a TcxImage.Canvas( DeveloperExpress TImage) insead of the form?

procedure TFormAdvGeometries.Create_FRadialGradientBrush;
var
//  aGradientStops: array of TD2D1GradientStop;
//  aGradBrushProps: TD2D1RadialGradientBrushProperties;
//  aGradStopsCollection: ID2D1GradientStopCollection;

  gradColors: array of TColor;
begin
  SetLength(gradColors, 3);
  gradColors[0] := TColor($00D7FF); // Gold (D2D1Helper.h)
  gradColors[1] := TColor($00A5FF); // Orange (D2D1Helper.h)
  gradColors[2] := TColor($0045FF); // OrangeRed (D2D1Helper.h)


  // this is a place-holder.
  // Code below assumes equal spread for positions in gradient stops
  FRadialGradientBrush := d2dCanvas.CreateBrush(
    gradColors,
    D2D1PointF(330, 330),
    D2D1PointF(140, 140),
    140,
    140
    );
end;

procedure TFormAdvGeometries.Create_FGridPatternBitmapBrush;
var
  gridBrush: ID2D1SolidColorBrush;
  bmpBrushProps: D2D1_BITMAP_BRUSH_PROPERTIES;
  bitmapRenderTarget: ID2D1BitmapRenderTarget;
  bmpSize: D2D_SIZE_F;
  gridBitmap: ID2D1Bitmap;
begin
  bmpSize.width := 10;
  bmpSize.height := 10;
  d2dCanvas.RenderTarget.CreateCompatibleRenderTarget(
    @bmpSize, nil, nil, 0, bitmapRenderTarget);
  bitmapRenderTarget.CreateSolidColorBrush(
    D2D1ColorF(0.93, 0.94, 0.96, 1), nil, gridBrush);
  bitmapRenderTarget.BeginDraw;
  bitmapRenderTarget.FillRectangle(Rect(0, 0, 10, 1), gridBrush);
  bitmapRenderTarget.FillRectangle(Rect(0, 0, 1, 10)开发者_运维问答, gridBrush);
  bitmapRenderTarget.EndDraw;
  bitmapRenderTarget.GetBitmap(gridBitmap);
  bmpBrushProps.extendModeX := D2D1_EXTEND_MODE_WRAP;
  bmpBrushProps.extendModeY := D2D1_EXTEND_MODE_WRAP;
  bmpBrushProps.interpolationMode := 0; // could be 1
  d2dCanvas.RenderTarget.CreateBitmapBrush(
    gridBitmap, @bmpBrushProps, nil, FGridPatternBitmapBrush);
end;

procedure TFormAdvGeometries.CreateDeviceResources;
begin
  Create_FRadialGradientBrush;
  Create_FGridPatternBitmapBrush;
end;

procedure TFormAdvGeometries.Paint;
var defMatrix: TD2DMatrix3x2F;
begin
  inherited;

  CreateDeviceResources;

  d2dCanvas.BeginDraw;
  try
    d2dCanvas.RenderTarget.GetTransform (defMatrix);

    // fill with white color the whole window
    d2dCanvas.RenderTarget.Clear(D2D1ColorF(clWhite));

    // fill canvas with little blue rectangles
    d2dCanvas.Brush.Handle := FGridPatternBitmapBrush;
    d2dCanvas.Rectangle(0, 0, ClientWidth + 50, ClientHeight + 50);

    // reset standard transformation
    d2dCanvas.RenderTarget.SetTransform (defMatrix);
  finally
    d2dCanvas.EndDraw;
  end;
end;

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You need to change the constructor of the d2dCanvas.

Currently it's

  d2dCanvas := TDirect2DCanvas.Create(Handle);

which is passing the forms handle to create the canvas.

I don't have Delphi 2010 (Which it seems is shipped with required units for the demo) but I think

  d2dCanvas := TDirect2DCanvas.Create(MyTcxImage.Canvas.Canvas, Rect(0,0, MyTcxImage.Width,MyTcxImage.Height));

should do the trick

You'll need to pass Canvas.Canvas to this constructor because the cx components (at least my version of) use a TcxCanvas which contains a TCanvas.

You may be able to pass the Window Handle of the TcxImage Control to the Direct2DCanvas constructor.