internal PaintEventArgs(
Gdi32.HDC hdc,
Rectangle clipRect,
DrawingEventFlags flags = DrawingEventFlags.CheckState)
{
_event = new DrawingEventArgs(hdc, clipRect, flags);
}
internal PaintEventArgs(
Graphics graphics,
Rectangle clipRect,
DrawingEventFlags flags)
{
_event = new DrawingEventArgs(graphics, clipRect, flags);
SaveStateIfNeeded(graphics);
}
/// <summary>
/// Internal version of constructor for performance. We try to avoid getting the graphics object until needed.
/// </summary>
public DrawingEventArgs(
Gdi32.HDC dc,
Rectangle clipRect,
DrawingEventFlags flags)
{
_hdc = dc;
_graphics = null;
_oldPalette = default;
Flags = flags;
ClipRectangle = clipRect;
}
public DrawingEventArgs(
Graphics graphics,
Rectangle clipRect,
DrawingEventFlags flags)
{
_graphics = graphics.OrThrowIfNull();
_hdc = default;
_oldPalette = default;
CheckGraphicsForState(graphics, flags);
ClipRectangle = clipRect;
Flags = flags;
}
public DrawingEventArgs(
Graphics graphics,
Rectangle clipRect,
DrawingEventFlags flags)
{
_graphics = graphics ?? throw new ArgumentNullException(nameof(graphics));
_hdc = default;
_oldPalette = default;
CheckGraphicsForState(graphics, flags);
ClipRectangle = clipRect;
Flags = flags;
}
internal static void CheckGraphicsForState(Graphics?graphics, DrawingEventFlags flags)
{
if (graphics is null || !flags.HasFlag(DrawingEventFlags.CheckState) ||
flags.HasFlag(DrawingEventFlags.GraphicsStateUnclean))
{
return;
}
// Check to see if we've actually corrupted the state
graphics.GetContextInfo(out PointF offset, out Region? clip);
using (clip)
{
bool isInfinite = clip?.IsInfinite(graphics) ?? true;
Debug.Assert(offset.IsEmpty, "transform has been modified");
Debug.Assert(isInfinite, "clipping as been applied");
}
}
internal static void CheckGraphicsForState(Graphics?graphics, DrawingEventFlags flags)
{
if (graphics is null || !flags.HasFlag(DrawingEventFlags.CheckState) ||
flags.HasFlag(DrawingEventFlags.GraphicsStateUnclean))
{
return;
}
// Check to see if we've actually corrupted the state
object[] data = (object[])graphics.GetContextInfo();
using Region clipRegion = (Region)data[0];
using Matrix worldTransform = (Matrix)data[1];
float[] elements = worldTransform?.Elements !;
bool isInfinite = clipRegion.IsInfinite(graphics);
Debug.Assert((int)elements[4] == 0 && (int)elements[5] == 0, "transform has been modified");
Debug.Assert(isInfinite, "clipping as been applied");
}
/// <summary>
/// Internal version of constructor for performance. We try to avoid getting the graphics object until needed.
/// </summary>
public DrawingEventArgs(
Gdi32.HDC dc,
Rectangle clipRect,
DrawingEventFlags flags)
{
ArgumentValidation.ThrowIfNull(dc);
#if DEBUG
Gdi32.OBJ type = Gdi32.GetObjectType(dc);
Debug.Assert(type == Gdi32.OBJ.DC ||
type == Gdi32.OBJ.ENHMETADC ||
type == Gdi32.OBJ.MEMDC ||
type == Gdi32.OBJ.METADC);
#endif
_hdc = dc;
_graphics = null;
_oldPalette = default;
Flags = flags;
ClipRectangle = clipRect;
}
/// <summary>
/// Internal version of constructor for performance. We try to avoid getting the graphics object until needed.
/// </summary>
public DrawingEventArgs(
Gdi32.HDC dc,
Rectangle clipRect,
DrawingEventFlags flags)
{
if (dc.IsNull)
{
throw new ArgumentNullException(nameof(dc));
}
#if DEBUG
Gdi32.OBJ type = Gdi32.GetObjectType(dc);
Debug.Assert(type == Gdi32.OBJ.DC ||
type == Gdi32.OBJ.ENHMETADC ||
type == Gdi32.OBJ.MEMDC ||
type == Gdi32.OBJ.METADC);
#endif
_hdc = dc;
_graphics = null;
_oldPalette = default;
Flags = flags;
ClipRectangle = clipRect;
}
