public float GetTypographicWidth(TFont font, AttributedGlyphRun <TFont, TGlyph> run)
{
var aString = run.ToNsAttributedString();
using (var ctLine = new CTLine(aString))
return((float)ctLine.GetTypographicBounds());
}
// Public method to create a rect for a given range in the text contents
// Called by our EditableTextRange to implement the required
// UITextInput:firstRectForRange method
public CGRect FirstRect(NSRange range)
{
int index = (int)range.Location;
// Iterate over our CTLines, looking for the line that encompasses the given range
var lines = frame.GetLines();
for (int i = 0; i < lines.Length; i++)
{
CTLine line = lines [i];
NSRange lineRange = line.StringRange;
int localIndex = index - (int)lineRange.Location;
if (localIndex >= 0 && localIndex < lineRange.Length)
{
// For this sample, we use just the first line that intersects range
int finalIndex = (int)Math.Min(lineRange.Location + lineRange.Length, range.Location + range.Length);
// Create a rect for the given range within this line
nfloat xStart = line.GetOffsetForStringIndex(index);
nfloat xEnd = line.GetOffsetForStringIndex(finalIndex);
var origins = new CGPoint [lines.Length];
frame.GetLineOrigins(new NSRange(i, 0), origins);
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
return(new CGRect(xStart, origins [0].Y - descent, xEnd - xStart, ascent + descent));
}
}
return(CGRect.Empty);
}
public static TextMetrics GlobalMeasureText(string text, Font font)
{
if (string.IsNullOrEmpty(text))
{
return(new TextMetrics());
}
if (font == null)
{
throw new ArgumentNullException("font");
}
using (var atext = new NSMutableAttributedString(text)) {
atext.AddAttributes(new CTStringAttributes {
ForegroundColorFromContext = true,
Font = font.GetCTFont(),
}.Dictionary, new NSRange(0, text.Length));
using (var l = new CTLine(atext)) {
nfloat asc, desc, lead;
var len = l.GetTypographicBounds(out asc, out desc, out lead);
return(new TextMetrics {
Width = len,
Ascent = asc,
Descent = desc,
});
}
}
}
static void PrepareGlyphArcInfo (CTLine line, long glyphCount, GlyphArcInfo[] glyphArcInfo)
{
var runArray = line.GetGlyphRuns ();
// Examine each run in the line, updating glyphOffset to track how far along the run is
// in terms of glyphCount.
long glyphOffset = 0;
nfloat ascent = 0;
nfloat descent = 0;
nfloat leading = 0;
foreach (var run in runArray) {
var runGlyphCount = run.GlyphCount;
// Ask for the width of each glyph in turn.
var runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++) {
glyphArcInfo [runGlyphIndex + glyphOffset].width = (float)run.GetTypographicBounds (new NSRange (runGlyphIndex, 1), out ascent, out descent, out leading);
}
glyphOffset += runGlyphCount;
}
var lineLength = line.GetTypographicBounds (out ascent, out descent, out leading);
var prevHalfWidth = glyphArcInfo [0].width / 2.0;
glyphArcInfo [0].angle = (float)((prevHalfWidth / lineLength) * Math.PI);
var lineGlyphIndex = 1;
for (; lineGlyphIndex < glyphCount; lineGlyphIndex++) {
var halfWidth = glyphArcInfo [lineGlyphIndex].width / 2.0;
var prevCenterToCenter = prevHalfWidth + halfWidth;
glyphArcInfo [lineGlyphIndex].angle = (float)((prevCenterToCenter / lineLength) * Math.PI);
prevHalfWidth = halfWidth;
}
}
public double GetBaseLine()
{
using (var line = new CTLine(TextStorage))
{
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
return(ascent);
}
}
public override double GetBaseline(object backend)
{
LayoutInfo li = (LayoutInfo)backend;
using (var line = new CTLine(CreateAttributedString(li))) {
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
return((double)ascent);
}
}
public void DrawText(string text, Rect frame, Font font, TextAlignment alignment = TextAlignment.Left, Pen pen = null, Brush brush = null)
{
if (string.IsNullOrEmpty(text))
{
return;
}
if (font == null)
{
throw new ArgumentNullException("font");
}
SetBrush(brush);
using (var atext = new NSMutableAttributedString(text)) {
atext.AddAttributes(new CTStringAttributes {
ForegroundColorFromContext = true,
Font = font.GetCTFont(),
}, new NSRange(0, text.Length));
using (var l = new CTLine(atext)) {
nfloat asc, desc, lead;
var len = l.GetTypographicBounds(out asc, out desc, out lead);
var pt = frame.TopLeft;
switch (alignment)
{
case TextAlignment.Left:
pt.X = frame.X;
break;
case TextAlignment.Center:
pt.X = frame.X + (frame.Width - len) / 2;
break;
case TextAlignment.Right:
pt.X = frame.Right - len;
break;
}
context.SaveState();
context.TranslateCTM((nfloat)(pt.X), (nfloat)(pt.Y));
context.TextPosition = CGPoint.Empty;
l.Draw(context);
context.RestoreState();
}
}
}
// This only handles one character for right now
internal static void GetCharABCWidthsFloat(char characters, CTFont font, out ABCFloat[] abc)
{
var atts = buildAttributedString(characters.ToString(), font);
// for now just a line not sure if this is going to work
CTLine line = new CTLine(atts);
float ascent;
float descent;
float leading;
abc = new ABCFloat[1];
abc[0].abcfB = (float)line.GetTypographicBounds(out ascent, out descent, out leading);
abc [0].abcfB += leading;
}
// Public method to determine the CGRect for the insertion point or selection, used
// when creating or updating our SimpleCaretView instance
public CGRect CaretRect(int index)
{
var lines = frame.GetLines();
// Special case, no text
if (text.Length == 0)
{
CGPoint origin = new CGPoint(Bounds.GetMinX(), Bounds.GetMinY() - font.Leading);
// Note: using fabs() for typically negative descender from fonts
return(new CGRect(origin.X, origin.Y - (nfloat)Math.Abs(font.Descender), 3, font.Ascender + (nfloat)Math.Abs(font.Descender)));
}
// Special case, insertion point at final position in text after newline
if (index == text.Length && text.EndsWith("\n"))
{
CTLine line = lines [lines.Length - 1];
NSRange range = line.StringRange;
nfloat xPos = line.GetOffsetForStringIndex(range.Location);
var origins = new CGPoint [lines.Length];
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
frame.GetLineOrigins(new NSRange(lines.Length - 1, 0), origins);
// Place point after last line, including any font leading spacing if applicable
origins[0].Y -= font.Leading;
return(new CGRect(xPos, origins [0].Y - descent, 3, ascent + descent));
}
// Regular case, caret somewhere within our text content range
for (int i = 0; i < lines.Length; i++)
{
CTLine line = lines [i];
NSRange range = line.StringRange;
int localIndex = index - (int)range.Location;
if (localIndex >= 0 && localIndex <= range.Length)
{
// index is in the range for this line
nfloat xPos = line.GetOffsetForStringIndex(index);
var origins = new CGPoint [lines.Length];
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
frame.GetLineOrigins(new NSRange(i, 0), origins);
// Make a small "caret" rect at the index position
return(new CGRect(xPos, origins [0].Y - descent, 3, ascent + descent));
}
}
return(CGRect.Empty);
}
public static ABC GetCharWidthABC(char ch, Font font, System.Drawing.Graphics gr)
{
ABC[] _temp = new ABC[1];
var nativFont = CreateFont(font.Name, font.Size, font.Style, font.GdiCharSet, font.GdiVerticalFont);
var atts = buildAttributedString(ch.ToString(), nativFont);
// for now just a line not sure if this is going to work
CTLine line = new CTLine(atts);
float ascent;
float descent;
float leading;
_temp[0].abcB = (uint)line.GetTypographicBounds(out ascent, out descent, out leading);
return(_temp[0]);
}
internal static CCSize MeasureString(string textg, CTFont font, CCRect rect)
{
var atts = buildAttributedString(textg, font);
// for now just a line not sure if this is going to work
CTLine line = new CTLine(atts);
// Create and initialize some values from the bounds.
float ascent;
float descent;
float leading;
double lineWidth = line.GetTypographicBounds(out ascent, out descent, out leading);
var measure = new CCSize((float)lineWidth + leading, ascent + descent);
return(measure);
}
public void DrawText(string text, float x, float y, float width, float height, Xamarin.Forms.TextAlignment hAlignment, Xamarin.Forms.TextAlignment vAlignment)
{
if (font == null || font.NativeFont == null)
{
return;
}
var attributedString = new NSAttributedString(text, new CTStringAttributes()
{
Font = font.NativeFont, ForegroundColorFromContext = true
});
CTLine ctLine = new CTLine(attributedString);
CGSize size = new CGSize((float)ctLine.GetTypographicBounds(), font.NativeFont.CapHeightMetric + font.NativeFont.DescentMetric);
if ((hAlignment & Xamarin.Forms.TextAlignment.Center) != 0)
{
x += (width - (float)size.Width) / 2;
}
else if ((hAlignment & Xamarin.Forms.TextAlignment.End) != 0)
{
x += width - (float)size.Width;
}
if ((vAlignment & Xamarin.Forms.TextAlignment.Center) != 0)
{
y += (height - (float)size.Height) / 2;
}
else if ((vAlignment & Xamarin.Forms.TextAlignment.End) != 0)
{
y += height - (float)size.Height;
}
context.SaveState();
context.ScaleCTM(1f, -1f);
context.TextPosition = new CGPoint(x, -y - font.NativeFont.CapHeightMetric);
ctLine.Draw(context);
context.RestoreState();
ctLine.Dispose();
attributedString.Dispose();
}
// Helper method for drawing the current selection range (as a simple filled rect)
void DrawRangeAsSelection(NSRange selectionRange)
{
// If not in editing mode, we do not draw selection rects
if (!IsEditing)
{
return;
}
// If selection range empty, do not draw
if (selectionRange.Length == 0 || selectionRange.Location == NSRange.NotFound)
{
return;
}
// set the fill color to the selection color
SelectionColor.SetFill();
// Iterate over the lines in our CTFrame, looking for lines that intersect
// with the given selection range, and draw a selection rect for each intersection
var lines = frame.GetLines();
for (int i = 0; i < lines.Length; i++)
{
CTLine line = lines [i];
NSRange lineRange = line.StringRange;
NSRange range = new NSRange(lineRange.Location, lineRange.Length);
NSRange intersection = RangeIntersection(range, selectionRange);
if (intersection.Location != NSRange.NotFound && intersection.Length > 0)
{
// The text range for this line intersects our selection range
nfloat xStart = line.GetOffsetForStringIndex(intersection.Location);
nfloat xEnd = line.GetOffsetForStringIndex(intersection.Location + intersection.Length);
var origin = new CGPoint [lines.Length];
// Get coordinate and bounds information for the intersection text range
frame.GetLineOrigins(new NSRange(i, 0), origin);
nfloat ascent, descent, leading;
line.GetTypographicBounds(out ascent, out descent, out leading);
// Create a rect for the intersection and draw it with selection color
CGRect selectionRect = new CGRect(xStart, origin [0].Y - descent, xEnd - xStart, ascent + descent);
UIGraphics.RectFill(selectionRect);
}
}
}
static void PrepareGlyphArcInfo(CTLine line, long glyphCount, GlyphArcInfo[] glyphArcInfo)
{
var runArray = line.GetGlyphRuns();
// Examine each run in the line, updating glyphOffset to track how far along the run is
// in terms of glyphCount.
long glyphOffset = 0;
nfloat ascent = 0;
nfloat descent = 0;
nfloat leading = 0;
foreach (var run in runArray)
{
var runGlyphCount = run.GlyphCount;
// Ask for the width of each glyph in turn.
var runGlyphIndex = 0;
for (; runGlyphIndex < runGlyphCount; runGlyphIndex++)
{
glyphArcInfo[runGlyphIndex + glyphOffset].width = (float)run.GetTypographicBounds(new NSRange(runGlyphIndex, 1), out ascent, out descent, out leading);
}
glyphOffset += runGlyphCount;
}
var lineLength = line.GetTypographicBounds(out ascent, out descent, out leading);
var prevHalfWidth = glyphArcInfo[0].width / 2.0;
glyphArcInfo[0].angle = (float)((prevHalfWidth / lineLength) * Math.PI);
var lineGlyphIndex = 1;
for (; lineGlyphIndex < glyphCount; lineGlyphIndex++)
{
var halfWidth = glyphArcInfo[lineGlyphIndex].width / 2.0;
var prevCenterToCenter = prevHalfWidth + halfWidth;
glyphArcInfo[lineGlyphIndex].angle = (float)((prevCenterToCenter / lineLength) * Math.PI);
prevHalfWidth = halfWidth;
}
}
public Xamarin.Forms.Size MeasureText(string text)
{
if (font == null || font.NativeFont == null)
{
return(Xamarin.Forms.Size.Zero);
}
var attributedString = new NSAttributedString(text, new CTStringAttributes()
{
Font = font.NativeFont, ForegroundColorFromContext = true
});
CTLine ctLine = new CTLine(attributedString);
Xamarin.Forms.Size size = new Xamarin.Forms.Size((float)ctLine.GetTypographicBounds(), font.NativeFont.CapHeightMetric + font.NativeFont.DescentMetric);
ctLine.Dispose();
attributedString.Dispose();
return(size);
}
public SizeF MeasureString(string textg, Font font, RectangleF rect)
{
// As per documentation
// https://developer.apple.com/library/mac/#documentation/GraphicsImaging/Conceptual/drawingwithquartz2d/dq_text/dq_text.html#//apple_ref/doc/uid/TP30001066-CH213-TPXREF101
//
// * Note * Not sure if we should save off the graphic state, set context transform to identity
// and restore state to do the measurement. Something to be looked into.
// context.TextPosition = rect.Location;
// var startPos = context.TextPosition;
// context.SelectFont ( font.nativeFont.PostScriptName,
// font.SizeInPoints,
// CGTextEncoding.MacRoman);
// context.SetTextDrawingMode(CGTextDrawingMode.Invisible);
//
// context.SetCharacterSpacing(1);
// var textMatrix = CGAffineTransform.MakeScale(1f,-1f);
// context.TextMatrix = textMatrix;
//
// context.ShowTextAtPoint(rect.X, rect.Y, textg, textg.Length);
// var endPos = context.TextPosition;
//
// var measure = new SizeF(endPos.X - startPos.X, font.nativeFont.CapHeightMetric);
var atts = buildAttributedString(textg, font);
// for now just a line not sure if this is going to work
CTLine line = new CTLine(atts);
var lineBounds = line.GetImageBounds(context);
// Create and initialize some values from the bounds.
float ascent;
float descent;
float leading;
double lineWidth = line.GetTypographicBounds(out ascent, out descent, out leading);
var measure = new SizeF((float)lineWidth, ascent + descent);
return(measure);
}
public void DrawText(string text, Rect frame, Font font, TextAlignment alignment = TextAlignment.Left, Pen pen = null, Brush brush = null)
{
if (string.IsNullOrEmpty(text))
{
return;
}
if (font == null)
{
throw new ArgumentNullException("font");
}
SetBrush(brush);
// string fontName = font.Name;
// context.SelectFont (font.Name, (nfloat)font.Size, CGTextEncoding.MacRoman);
//
// context.ShowTextAtPoint ((nfloat)frame.X, (nfloat)frame.Y, text);
var pt = frame.TopLeft;
using (var atext = new NSMutableAttributedString(text)) {
atext.AddAttributes(new CTStringAttributes {
ForegroundColorFromContext = true,
Font = font.GetCTFont(),
}, new NSRange(0, text.Length));
using (var l = new CTLine(atext)) {
nfloat asc, desc, lead;
var width = l.GetTypographicBounds(out asc, out desc, out lead);
context.SaveState();
context.TranslateCTM((nfloat)(pt.X - width / 2), (nfloat)(pt.Y + desc));
context.TextPosition = CGPoint.Empty;
l.Draw(context);
context.RestoreState();
}
}
}
public void DrawText(string text, Rect frame, Font font, TextAlignment alignment = TextAlignment.Left, Pen pen = null, Brush brush = null)
{
if (string.IsNullOrEmpty (text))
return;
if (font == null)
throw new ArgumentNullException ("font");
SetBrush (brush);
// string fontName = font.Name;
// context.SelectFont (font.Name, (nfloat)font.Size, CGTextEncoding.MacRoman);
//
// context.ShowTextAtPoint ((nfloat)frame.X, (nfloat)frame.Y, text);
var pt = frame.TopLeft;
using (var atext = new NSMutableAttributedString (text)) {
atext.AddAttributes (new CTStringAttributes {
ForegroundColorFromContext = true,
Font = font.GetCTFont (),
}, new NSRange (0, text.Length));
using (var l = new CTLine (atext)) {
nfloat asc, desc, lead;
var width = l.GetTypographicBounds (out asc, out desc, out lead);
context.SaveState ();
context.TranslateCTM ((nfloat)(pt.X - width / 2), (nfloat)(pt.Y + desc));
context.TextPosition = CGPoint.Empty;
l.Draw (context);
context.RestoreState ();
}
}
}
public void DrawText (string text, Rect frame, Font font, TextAlignment alignment = TextAlignment.Left, Pen pen = null, Brush brush = null)
{
if (string.IsNullOrEmpty (text))
return;
if (font == null)
throw new ArgumentNullException ("font");
SetBrush (brush);
using (var atext = new NSMutableAttributedString (text)) {
atext.AddAttributes (new CTStringAttributes {
ForegroundColorFromContext = true,
StrokeColor = pen != null ? pen.Color.GetCGColor () : null,
Font = font.GetCTFont (),
}, new NSRange (0, text.Length));
using (var l = new CTLine (atext)) {
nfloat asc, desc, lead;
var len = l.GetTypographicBounds (out asc, out desc, out lead);
var pt = frame.TopLeft;
switch (alignment) {
case TextAlignment.Left:
pt.X = frame.X;
break;
case TextAlignment.Center:
pt.X = frame.X + (frame.Width - len) / 2;
break;
case TextAlignment.Right:
pt.X = frame.Right - len;
break;
}
context.SaveState ();
context.TranslateCTM ((nfloat)(pt.X), (nfloat)(pt.Y));
context.TextPosition = CGPoint.Empty;
l.Draw (context);
context.RestoreState ();
}
}
}
public static TextMetrics GlobalMeasureText (string text, Font font)
{
if (string.IsNullOrEmpty(text))
return new TextMetrics ();
if (font == null)
throw new ArgumentNullException("font");
using (var atext = new NSMutableAttributedString (text)) {
atext.AddAttributes (new CTStringAttributes {
ForegroundColorFromContext = true,
Font = font.GetCTFont (),
}, new NSRange (0, text.Length));
using (var l = new CTLine (atext)) {
nfloat asc, desc, lead;
var len = l.GetTypographicBounds (out asc, out desc, out lead);
return new TextMetrics {
Width = len,
Ascent = asc,
Descent = desc,
};
}
}
}
static double GetLineWidth(CTLine l)
{
// Pango does not consider trailing whitespace in its size
return(l.GetTypographicBounds() - l.TrailingWhitespaceWidth);
}
private static void DrawText(this CGContext context, string source, float x, float y, string fontName, float fontSize, bool isCenter)
{
var stringAttributes = new CTStringAttributes
{
ForegroundColorFromContext = true,
Font = new CTFont(fontName, fontSize)
};
var attributedString = new NSAttributedString(source, stringAttributes);
context.TextPosition = new PointF(x, y);
using (var textLine = new CTLine(attributedString))
{
if (isCenter)
context.TextPosition = new PointF((float)(x - (textLine.GetTypographicBounds() / 2)), y);
textLine.Draw(context);
}
}
