using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing.Drawing2D;
namespace System.Drawing.Html
{
/// <summary>
/// Provides some drawing functionallity
/// </summary>
internal static class CssDrawingHelper
{
/// <summary>
/// Border specifiers
/// </summary>
internal enum Border
{
Top, Right, Bottom, Left
}
/// <summary>
/// Rounds the specified point
/// </summary>
/// <param name="p"></param>
/// <param name="b"></param>
/// <returns></returns>
private static PointF RoundP(PointF p, CssBox b)
{
//HACK: Don't round if in printing mode
//return Point.Round(p);
return p;
}
/// <summary>
/// Rounds the specified rectangle
/// </summary>
/// <param name="p"></param>
/// <param name="b"></param>
/// <returns></returns>
private static RectangleF RoundR(RectangleF r, CssBox b)
{
//HACK: Don't round if in printing mode
return Rectangle.Round(r);
}
/// <summary>
/// Makes a border path
/// </summary>
/// <param name="border">Desired border</param>
/// <param name="b">Box wich the border corresponds</param>
/// <param name="isLineStart">Specifies if the border is for a starting line (no bevel on left)</param>
/// <param name="isLineEnd">Specifies if the border is for an ending line (no bevel on right)</param>
/// <returns>Beveled border path</returns>
public static GraphicsPath GetBorderPath(Border border, CssBox b, RectangleF r, bool isLineStart, bool isLineEnd)
{
PointF[] pts = new PointF[4];
float bwidth = 0;
GraphicsPath corner = null;
switch (border)
{
case Border.Top:
bwidth = b.ActualBorderTopWidth;
pts[0] = RoundP(new PointF(r.Left + b.ActualCornerNW, r.Top), b);
pts[1] = RoundP(new PointF(r.Right - b.ActualCornerNE, r.Top), b);
pts[2] = RoundP(new PointF(r.Right - b.ActualCornerNE, r.Top + bwidth), b);
pts[3] = RoundP(new PointF(r.Left + b.ActualCornerNW, r.Top + bwidth), b);
if (isLineEnd && b.ActualCornerNE == 0f) pts[2].X -= b.ActualBorderRightWidth;
if (isLineStart && b.ActualCornerNW == 0f) pts[3].X += b.ActualBorderLeftWidth;
if (b.ActualCornerNW > 0f) corner = CreateCorner(b, r, 1);
break;
case Border.Right:
bwidth = b.ActualBorderRightWidth;
pts[0] = RoundP(new PointF(r.Right - bwidth, r.Top + b.ActualCornerNE), b);
pts[1] = RoundP(new PointF(r.Right, r.Top + b.ActualCornerNE), b);
pts[2] = RoundP(new PointF(r.Right, r.Bottom - b.ActualCornerSE), b);
pts[3] = RoundP(new PointF(r.Right - bwidth, r.Bottom - b.ActualCornerSE), b);
if (b.ActualCornerNE == 0f) pts[0].Y += b.ActualBorderTopWidth;
if (b.ActualCornerSE == 0f) pts[3].Y -= b.ActualBorderBottomWidth;
if (b.ActualCornerNE > 0f) corner = CreateCorner(b, r, 2);
break;
case Border.Bottom:
bwidth = b.ActualBorderBottomWidth;
pts[0] = RoundP(new PointF(r.Left + b.ActualCornerSW, r.Bottom - bwidth), b);
pts[1] = RoundP(new PointF(r.Right - b.ActualCornerSE, r.Bottom - bwidth), b);
pts[2] = RoundP(new PointF(r.Right - b.ActualCornerSE, r.Bottom), b);
pts[3] = RoundP(new PointF(r.Left + b.ActualCornerSW, r.Bottom), b);
if (isLineStart && b.ActualCornerSW == 0f) pts[0].X += b.ActualBorderLeftWidth;
if (isLineEnd && b.ActualCornerSE == 0f) pts[1].X -= b.ActualBorderRightWidth;
if (b.ActualCornerSE > 0f) corner = CreateCorner(b, r, 3);
break;
case Border.Left:
bwidth = b.ActualBorderLeftWidth;
pts[0] = RoundP(new PointF(r.Left, r.Top + b.ActualCornerNW), b);
pts[1] = RoundP(new PointF(r.Left + bwidth, r.Top + b.ActualCornerNW), b);
pts[2] = RoundP(new PointF(r.Left + bwidth, r.Bottom - b.ActualCornerSW), b);
pts[3] = RoundP(new PointF(r.Left, r.Bottom - b.ActualCornerSW), b);
if (b.ActualCornerNW == 0f) pts[1].Y += b.ActualBorderTopWidth;
if (b.ActualCornerSW == 0f) pts[2].Y -= b.ActualBorderBottomWidth;
if (b.ActualCornerSW > 0f) corner = CreateCorner(b, r, 4);
break;
}
GraphicsPath path = new GraphicsPath(pts, new byte[] { (byte)PathPointType.Line, (byte)PathPointType.Line, (byte)PathPointType.Line, (byte)PathPointType.Line });
if (corner != null)
{
path.AddPath(corner, true);
}
return path;
}
/// <summary>
/// Creates the corner to place with the borders
/// </summary>
/// <param name="outer"></param>
/// <param name="inner"></param>
/// <param name="startAngle"></param>
/// <param name="sweepAngle"></param>
/// <returns></returns>
private static GraphicsPath CreateCorner(CssBox b, RectangleF r, int cornerIndex)
{
GraphicsPath corner = new GraphicsPath();
RectangleF outer = RectangleF.Empty;
RectangleF inner = RectangleF.Empty;
float start1 = 0;
float start2 = 0;
switch (cornerIndex)
{
case 1:
outer = new RectangleF(r.Left, r.Top, b.ActualCornerNW, b.ActualCornerNW);
inner = RectangleF.FromLTRB(outer.Left + b.ActualBorderLeftWidth, outer.Top + b.ActualBorderTopWidth, outer.Right, outer.Bottom);
start1 = 180;
start2 = 270;
break;
case 2:
outer = new RectangleF(r.Right - b.ActualCornerNE, r.Top, b.ActualCornerNE, b.ActualCornerNE);
inner = RectangleF.FromLTRB(outer.Left, outer.Top + b.ActualBorderTopWidth, outer.Right - b.ActualBorderRightWidth, outer.Bottom);
outer.X -= outer.Width;
inner.X -= inner.Width;
start1 = -90;
start2 = 0;
break;
case 3:
outer = RectangleF.FromLTRB(r.Right - b.ActualCornerSE, r.Bottom - b.ActualCornerSE, r.Right, r.Bottom);
inner = new RectangleF(outer.Left, outer.Top, outer.Width - b.ActualBorderRightWidth, outer.Height - b.ActualBorderBottomWidth);
outer.X -= outer.Width;
outer.Y -= outer.Height;
inner.X -= inner.Width;
inner.Y -= inner.Height;
start1 = 0;
start2 = 90;
break;
case 4:
outer = new RectangleF(r.Left, r.Bottom - b.ActualCornerSW, b.ActualCornerSW, b.ActualCornerSW);
inner = RectangleF.FromLTRB( r.Left + b.ActualBorderLeftWidth , outer.Top , outer.Right, outer.Bottom - b.ActualBorderBottomWidth);
start1 = 90;
start2 = 180;
outer.Y -= outer.Height;
inner.Y -= inner.Height;
break;
}
if (outer.Width <= 0f) outer.Width = 1f;
if (outer.Height <= 0f) outer.Height = 1f;
if (inner.Width <= 0f) inner.Width = 1f;
if (inner.Height <= 0f) inner.Height = 1f;
outer.Width *= 2; outer.Height *= 2;
inner.Width *= 2; inner.Height *= 2;
outer = RoundR(outer, b); inner = RoundR(inner, b);
corner.AddArc(outer, start1, 90);
corner.AddArc(inner, start2, -90);
corner.CloseFigure();
return corner;
}
/// <summary>
/// Creates a rounded rectangle using the specified corner radius
/// </summary>
/// <param name="rect">Rectangle to round</param>
/// <param name="nwRadius">Radius of the north east corner</param>
/// <param name="neRadius">Radius of the north west corner</param>
/// <param name="seRadius">Radius of the south east corner</param>
/// <param name="swRadius">Radius of the south west corner</param>
/// <returns>GraphicsPath with the lines of the rounded rectangle ready to be painted</returns>
public static GraphicsPath GetRoundRect(RectangleF rect, float nwRadius, float neRadius, float seRadius, float swRadius)
{
/// NW-----NE
/// | |
/// | |
/// SW-----SE
GraphicsPath path = new GraphicsPath();
nwRadius *= 2;
neRadius *= 2;
seRadius *= 2;
swRadius *= 2;
//NW ---- NE
path.AddLine(rect.X + nwRadius, rect.Y, rect.Right - neRadius, rect.Y);
//NE Arc
if (neRadius > 0f)
{
path.AddArc(
RectangleF.FromLTRB(rect.Right - neRadius, rect.Top, rect.Right, rect.Top + neRadius),
-90, 90);
}
// NE
// |
// SE
path.AddLine(rect.Right, rect.Top + neRadius, rect.Right, rect.Bottom - seRadius);
//SE Arc
if (seRadius > 0f)
{
path.AddArc(
RectangleF.FromLTRB(rect.Right - seRadius, rect.Bottom - seRadius, rect.Right, rect.Bottom),
0, 90);
}
// SW --- SE
path.AddLine(rect.Right - seRadius, rect.Bottom, rect.Left + swRadius, rect.Bottom);
//SW Arc
if (swRadius > 0f)
{
path.AddArc(
RectangleF.FromLTRB(rect.Left, rect.Bottom - swRadius, rect.Left + swRadius, rect.Bottom),
90, 90);
}
// NW
// |
// SW
path.AddLine(rect.Left, rect.Bottom - swRadius, rect.Left, rect.Top + nwRadius);
//NW Arc
if (nwRadius > 0f)
{
path.AddArc(
RectangleF.FromLTRB(rect.Left, rect.Top, rect.Left + nwRadius, rect.Top + nwRadius),
180, 90);
}
path.CloseFigure();
return path;
}
/// <summary>
/// Makes the specified color darker
/// </summary>
/// <param name="c"></param>
/// <returns></returns>
public static Color Darken(Color c)
{
return Color.FromArgb(c.R / 2, c.G / 2, c.B / 2);
}
}
}
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