/// <summary>
/// Called by CanvasRenderingContext2D in order to notify parent objects
/// that changes were made, so redrawing should be performed if necessary.
/// </summary>
public void ReDraw()
{
//if this is IE
if (_paintSite != null)
{
var rect = new tagRECT();
rect.top = 0;
rect.bottom = height; // + _element.Top;
rect.left = 0;
rect.right = width; // + _element.Left;
_paintSite.InvalidateRect(ref rect);
}
// belongs in HTMLCanvasElement?
// _isChanged = true;
}
/// <summary>
/// IE will, in fact, call Draw() more than once in drawing the element, as it paints the element rectangle in successive horizontal bands.
/// For this reason, it is best to prepare an off-screen bitmap image before element invalidation, so that successive calls to Draw()
/// deal with an unchanging graphic. When IE calls Draw(), the drawing requirements dictated by IE are obtained through GetDrawInfo(),
/// and any necessary image transformation and clipping can then be applied before rendering with Graphics.DrawImage().
/// </summary>
/// <param name="rcBounds"></param>
/// <param name="rcUpdate"></param>
/// <param name="lDrawFlags"></param>
/// <param name="hdc"></param>
/// <param name="pvDrawObject"></param>
// FIXME: Move this to an IE specific HTMLCanvasElement implementation.
public void Draw(tagRECT rcBounds, tagRECT rcUpdate, int lDrawFlags, IntPtr hdc, IntPtr pvDrawObject)
{
// _element.Paint -= _element.HTMLCanvasElement_Paint;
_graphics = Graphics.FromHdc(hdc);
_graphics.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceOver;
// Apply any scaling, etc. to the output.
_HTML_PAINT_DRAW_INFO info;
_paintSite.GetDrawInfo(
(int)_HTML_PAINT_DRAW_INFO_FLAGS.HTMLPAINT_DRAWINFO_XFORM |
(int)_HTML_PAINT_DRAW_INFO_FLAGS.HTMLPAINT_DRAWINFO_UPDATEREGION,
out info);
var xform = new System.Drawing.Drawing2D.Matrix(
info.xform.eM11, info.xform.eM12,
info.xform.eM21, info.xform.eM22,
info.xform.eDx - rcBounds.left, info.xform.eDy - rcBounds.top);
_graphics.Transform = xform;
// Update clipping region.
var clip = new Region();
if (info.hrgnUpdate != IntPtr.Zero)
{
Region updateclip = Region.FromHrgn(info.hrgnUpdate);
clip.Intersect(updateclip);
clip.Translate(rcBounds.left, rcBounds.top);
}
_graphics.SetClip(clip, System.Drawing.Drawing2D.CombineMode.Replace);
if (init != null) //run only once
{
_init.GetType().InvokeMember("", System.Reflection.BindingFlags.InvokeMethod, null, _init,
new object[] { });
_init = null;
}
// _element.Draw(_graphics, rcBounds, rcUpdate);
_graphics.Dispose();
}
/// <summary>
/// Get necessary part of the whole image and draw it on the specified surface
/// </summary>
/// <param name="graphics">surface to draw</param>
/// <param name="rcBounds">allowed rectangle to draw in</param>
/// <param name="rcUpdate">rectangle to update</param>
private void Draw(Graphics graphics, tagRECT rcBounds, tagRECT rcUpdate)
{
Bitmap bitmap;
if (_canvas != null)
{
//_canvas.commit();
bitmap = _canvas.GetBitmap();
int x = rcUpdate.left;
int y = rcUpdate.top;
int x1 = rcUpdate.left - rcBounds.left;
int y1 = rcUpdate.top - rcBounds.top;
int width1 = rcUpdate.right - rcUpdate.left;
int height1 = rcUpdate.bottom - rcUpdate.top;
if (bitmap.Width < width1)
{
width1 = bitmap.Width;
}
if (bitmap.Height < height1)
{
height1 = bitmap.Height;
}
var rect = new Rectangle(x1,
y1,
width1,
height1);
//graphics.DrawRectangle(new Pen(Color.White), rect);
graphics.DrawImage(bitmap, x, y,
rect,
GraphicsUnit.Pixel);
}
}
/// <summary>
/// Called by CanvasRenderingContext2D in order to notify parent objects
/// that some changes were made in image, so redrawing should be performed if necessary.
/// </summary>
public void ReDraw()
{
//if this is IE
if (_paintSite != null)
{
var rect = new tagRECT();
rect.top = 0;
//rect.bottom = Top + height;
rect.bottom = height;
rect.left = 0;
rect.right = width;
//rect.right = Left + width;
_paintSite.InvalidateRect(ref rect);
}
//mark current canvas element as changed
_isChanged = true;
}
/// <summary>
/// Get rectagnle area equal to current control's size
/// </summary>
/// <returns></returns>
private tagRECT GetEmptyUpdate()
{
var update = new tagRECT();
update.left = 0;
update.top = 0;
update.right = width;
update.bottom = height;
return update;
}
/// <summary>
/// Get zero-initialized rectangle
/// </summary>
/// <returns></returns>
private tagRECT GetEmptyBound()
{
var bound = new tagRECT();
bound.left = 0;
bound.top = 0;
return bound;
}
/// <summary>
/// Get necessary part of the whole image and draw it on the specified surface
/// </summary>
/// <param name="graphics">surface to draw</param>
/// <param name="rcBounds">allowed rectangle to draw in</param>
/// <param name="rcUpdate">rectangle to update</param>
private void Draw(Graphics graphics, tagRECT rcBounds, tagRECT rcUpdate)
{
Bitmap bitmap;
if (_canvas != null)
{
int x = rcUpdate.left;
int y = rcUpdate.top;
int x1 = rcUpdate.left - rcBounds.left;
int y1 = rcUpdate.top - rcBounds.top;
int width1 = rcUpdate.right - rcUpdate.left;
int height1 = rcUpdate.bottom - rcUpdate.top;
lock (sync)
{
bitmap = _canvas.GetBitmap();
if (bitmap.Width < width1)
{
width1 = bitmap.Width;
}
if (bitmap.Height < height1)
{
height1 = bitmap.Height;
}
var rect = new Rectangle(x1,
y1,
width1,
height1);
graphics.DrawImage(bitmap, x, y,
rect,
GraphicsUnit.Pixel);
//graphics.DrawString(string.Format("bW = {0}, gW = {1}", bitmap.Width, graphics.VisibleClipBounds.Width), new Font("Arial", 5), new SolidBrush(Color.Black), x1, y1);
}
}
}
