/// <summary>Rounded axis-aligned rectangle shape.</summary>
/// <remarks>If the radius is 0, will create a normal rectangle instead. If the radius is too large compared to the rectangle, will create an ellipse instead.
/// Depending on the arguments, may also create oval shape, 2 half circles joined by a rectangle.</remarks>
public static iPathData roundedRectangle(Rect rect, Vector2 radius)
{
if (radius.X < 0 || radius.Y < 0)
{
throw new ArgumentException("Rounded rectangle radius must be non-negative");
}
if (radius.X < 1E-4f || radius.Y < 1E-4f)
{
return(rectangle(rect));
}
int collapsedFlags = 0;
if (radius.X * 2 >= rect.width)
{
radius.X = rect.width * 0.5f;
collapsedFlags |= 1;
}
if (radius.Y * 2 >= rect.width)
{
radius.Y = rect.height * 0.5f;
collapsedFlags |= 2;
}
if (collapsedFlags == 3)
{
// Both horizontal and vertical sides are collapsed. This turns rounded rectangle into an ellipse.
return(ellipse(rect.center, radius));
}
eArcFlags af = eArcFlags.ArcSmall | eArcFlags.DirCounterClockwise;
if (collapsedFlags == 0)
{
// Rounded rectangle
PathBuilder builder = new PathBuilder(4 * 5 + 3 * 2, 4 + 3);
using (var fb = builder.newFigure())
{
// Starting
fb.move(v2(rect.left + radius.X, rect.top));
// Top left
fb.arc(v2(rect.left, rect.top + radius.Y), radius, 90, af);
// Left
fb.line(v2(rect.left, rect.bottom - radius.Y));
// Bottom left
fb.arc(v2(rect.left + radius.X, rect.bottom), radius, 90, af);
// Bottom
fb.line(v2(rect.right - radius.X, rect.bottom));
// Bottom right
fb.arc(v2(rect.right, rect.bottom - radius.Y), radius, 90, af);
// Right
fb.line(v2(rect.right, rect.top + radius.Y));
// Top right
fb.arc(v2(rect.right - radius.X, rect.top), radius, 90, af);
// No top line, close the figure instead
fb.closeFigure();
}
return(builder.build());
}
if (collapsedFlags == 1)
{
// Oval with vertical lines
float xCenter = (rect.left + rect.right) * 0.5f;
PathBuilder builder = new PathBuilder(4 * 5 + 2, 4 + 1);
using (var fb = builder.newFigure())
{
// Starting
fb.move(v2(rect.right, rect.top + radius.Y));
// Top right
fb.arc(v2(xCenter, rect.top), radius, 90, af);
// Top left
fb.arc(v2(rect.left, rect.top + radius.Y), radius, 90, af);
// Left
fb.line(v2(rect.left, rect.bottom - radius.Y));
// Bottom left
fb.arc(v2(xCenter, rect.bottom), radius, 90, af);
// Bottom right
fb.arc(v2(rect.right, rect.bottom - radius.Y), radius, 90, af);
// No right line, close the figure instead
fb.closeFigure();
}
return(builder.build());
}
if (collapsedFlags == 2)
{
// Oval with horizontal lines
float yc = (rect.top + rect.bottom) * 0.5f;
PathBuilder builder = new PathBuilder(4 * 5 + 2, 4 + 1);
using (var fb = builder.newFigure())
{
// Starting
fb.move(v2(rect.left + radius.X, rect.top));
// Top left
fb.arc(v2(rect.left, yc), radius, 90, af);
// Bottom left
fb.arc(v2(rect.left + radius.X, rect.bottom), radius, 90, af);
// Bottom
fb.line(v2(rect.right - radius.X, rect.bottom));
// Bottom right
fb.arc(v2(rect.right, yc), radius, 90, af);
// Top right
fb.arc(v2(rect.right - radius.X, rect.top), radius, 90, af);
// No top line, close the figure instead
fb.closeFigure();
}
return(builder.build());
}
throw new ApplicationException("Unexpected");
}
void iFigureBuilder.arc(Vector2 endpoint, Vector2 size, float angleDegrees, eArcFlags flags)
{
ensureStart();
pb.addVec2(endpoint);
pb.addVec2(size);
pb.data.Add(angleDegrees);
addPoint(eSegmentKind.Arc, (byte)flags);
}
