/// <summary>
/// Draws text along a given line.
/// </summary>
/// <param name="target"></param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="color"></param>
/// <param name="size"></param>
/// <param name="text">Text.</param>
protected override void DrawLineText(Target2DWrapper <global::Android.Graphics.Canvas> target, double[] xa, double[] ya, string text, int color,
double size, int?haloColor, int?haloRadius, string fontName)
{
if (xa.Length > 1)
{
float sizeInPixels = this.ToPixels(size);
_paint.SubpixelText = true;
_paint.TextSize = (float)sizeInPixels;
_paint.AntiAlias = true;
// transform first.
double[] xTransformed = new double[xa.Length];
double[] yTransformed = new double[ya.Length];
for (int idx = 0; idx < xa.Length; idx++)
{
double[] transformed = this.Tranform(xa[idx], ya[idx]);
xTransformed [idx] = transformed [0];
yTransformed [idx] = transformed [1];
}
// get some metrics on the texts.
float[] characterWidths = new float[text.Length];
_paint.GetTextWidths(text, characterWidths);
// for (int idx = 0; idx < characterWidths.Length; idx++)
// {
// characterWidths[idx] = _target, _view, characterWidths[idx];
// }
var characterHeight = (float)sizeInPixels;
var textLength = characterWidths.Sum();
// calculate line length.
var lineLength = Polyline2D.Length(xTransformed, yTransformed);
if (lineLength > textLength * 1.2f)
{
// calculate the number of labels.
int labelCount = (int)System.Math.Floor(lineLength / (textLength * 10)) + 1;
// calculate positions of label(s).
double positionGap = lineLength / (labelCount + 1);
// draw each label.
for (double position = positionGap; position < lineLength; position = position + positionGap)
{
this.DrawLineTextSegment(target, xTransformed, yTransformed, text, color, size, haloColor, haloRadius, position, characterWidths,
textLength, characterHeight);
}
}
}
}
/// <summary>
/// Draws text along a line.
/// </summary>
/// <param name="target"></param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="text"></param>
/// <param name="color"></param>
/// <param name="size"></param>
/// <param name="haloColor"></param>
/// <param name="haloRadius"></param>
/// <param name="fontName"></param>
protected override void DrawLineText(Target2DWrapper <Graphics> target, double[] x, double[] y, string text, int color,
double size, int?haloColor, int?haloRadius, string fontName)
{
if (x.Length > 1)
{
float sizeInPixels = this.ToPixels(size);
Color textColor = Color.FromArgb(color);
Brush brush = new SolidBrush(textColor);
Brush haloBrush = null;
if (haloColor.HasValue && haloRadius.HasValue && haloRadius.Value > 0)
{
haloBrush = new SolidBrush(Color.FromArgb(haloColor.Value));
}
Font font = new Font(FontFamily.GenericSansSerif, sizeInPixels);
// get some metrics on the texts.
var characterWidths = GetCharacterWidths(target.Target, text, font);
for (int idx = 0; idx < characterWidths.Length; idx++)
{
characterWidths[idx] = (float)this.FromPixels(_target, _view, characterWidths[idx]);
}
var characterHeight = target.Target.MeasureString(text, font).Height;
var textLength = characterWidths.Sum();
// var avgCharacterWidth = textLength / characterWidths.Length;
// calculate line length.
var lineLength = Polyline2D.Length(x, y);
if (lineLength > textLength * 1.1f)
{
// calculate the number of labels.
int labelCount = (int)System.Math.Floor(lineLength / (textLength * 10)) + 1;
// calculate positions of label(s).
double positionGap = lineLength / (labelCount + 1);
// draw each label.
for (double position = positionGap; position < lineLength; position = position + positionGap)
{
this.DrawLineTextSegment(target, x, y, text, color, size, haloColor, haloRadius, position, characterWidths,
textLength, font, characterHeight, haloBrush, brush);
}
}
}
}
/// <summary>
/// Draws text along a given line.
/// </summary>
/// <param name="target"></param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="color"></param>
/// <param name="size"></param>
/// <param name="text">Text.</param>
protected override void DrawLineText(Target2DWrapper <CGContextWrapper> target, double[] xa, double[] ya, string text, int color,
double size, int?haloColor, int?haloRadius, string fontName)
{
float textSize = this.ToPixels(size) * _scaleFactor;
// transform first.
double[] xTransformed = new double[xa.Length];
double[] yTransformed = new double[ya.Length];
for (int idx = 0; idx < xa.Length; idx++)
{
double[] transformed = this.Transform(xa[idx], ya[idx]);
xTransformed[idx] = transformed[0];
yTransformed[idx] = transformed[1];
}
// set the fill color as the regular text-color.
target.Target.CGContext.InterpolationQuality = CGInterpolationQuality.High;
target.Target.CGContext.SetAllowsFontSubpixelQuantization(true);
target.Target.CGContext.SetAllowsFontSmoothing(true);
target.Target.CGContext.SetAllowsAntialiasing(true);
target.Target.CGContext.SetAllowsSubpixelPositioning(true);
target.Target.CGContext.SetShouldAntialias(true);
// get the glyhps/paths from the font.
CTFont font = this.GetFont(fontName, textSize);
CTStringAttributes stringAttributes = new CTStringAttributes
{
ForegroundColorFromContext = true,
Font = font
};
NSAttributedString attributedString = new NSAttributedString(text, stringAttributes);
CTLine line = new CTLine(attributedString);
RectangleF textBounds = line.GetBounds(CTLineBoundsOptions.UseOpticalBounds);
CTRun[] runs = line.GetGlyphRuns();
var lineLength = Polyline2D.Length(xTransformed, yTransformed);
// set the correct tranformations to draw the resulting paths.
target.Target.CGContext.SaveState();
//target.Target.CGContext.TranslateCTM (xPixels, yPixels);
//target.Target.CGContext.ConcatCTM (new CGAffineTransform (1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f));
foreach (CTRun run in runs)
{
ushort[] glyphs = run.GetGlyphs();
PointF[] positions = run.GetPositions();
float[] characterWidths = new float[glyphs.Length];
float previous = 0;
float textLength = (float)positions[positions.Length - 1].X;
//float textLength = (float)this.FromPixels(_target, _view, positions [positions.Length - 1].X);
if (lineLength > textLength * 1.2f)
{
for (int idx = 0; idx < characterWidths.Length - 1; idx++)
{
//characterWidths [idx] = (float)this.FromPixels(_target, _view, positions [idx + 1].X - previous);
characterWidths[idx] = (float)(positions[idx + 1].X - previous);
previous = positions[idx + 1].X;
}
characterWidths[characterWidths.Length - 1] = characterWidths[characterWidths.Length - 2];
float characterHeight = textBounds.Height;
this.DrawLineTextSegment(target, xTransformed, yTransformed, glyphs, color, haloColor, haloRadius,
lineLength / 2f, characterWidths, textLength, characterHeight, font);
}
}
target.Target.CGContext.RestoreState();
}
/// <summary>
/// Draws text along a given line.
/// </summary>
/// <param name="target"></param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="color"></param>
/// <param name="size"></param>
/// <param name="text">Text.</param>
protected override void DrawLineText(Target2DWrapper <CGContextWrapper> target, double[] x, double[] y, string text, int color,
double size, int?haloColor, int?haloRadius, string fontName)
{
double[] transformed = this.Tranform(x[0], y[0]);
float xPixels = (float)transformed[0];
float yPixels = (float)transformed[1];
float textSize = this.ToPixels(size);
// set the fill color as the regular text-color.
SimpleColor simpleColor = SimpleColor.FromArgb(color);
target.Target.CGContext.InterpolationQuality = CGInterpolationQuality.High;
target.Target.CGContext.SetAllowsFontSubpixelQuantization(true);
target.Target.CGContext.SetAllowsFontSmoothing(true);
target.Target.CGContext.SetFillColor(simpleColor.R / 256.0f, simpleColor.G / 256.0f, simpleColor.B / 256.0f,
simpleColor.A / 256.0f);
if (haloColor.HasValue) // set the stroke color as the halo color.
{
SimpleColor haloSimpleColor = SimpleColor.FromArgb(haloColor.Value);
target.Target.CGContext.SetStrokeColor(haloSimpleColor.R / 256.0f, haloSimpleColor.G / 256.0f, haloSimpleColor.B / 256.0f,
haloSimpleColor.A / 256.0f);
}
if (haloRadius.HasValue) // set the halo radius as line width.
{
target.Target.CGContext.SetLineWidth(haloRadius.Value);
}
// get the glyhps/paths from the font.
if (string.IsNullOrWhiteSpace(fontName))
{
fontName = "Arial";
}
CTFont font = new CTFont(fontName, textSize);
CTStringAttributes stringAttributes = new CTStringAttributes {
ForegroundColorFromContext = true,
Font = font
};
NSAttributedString attributedString = new NSAttributedString(text, stringAttributes);
CTLine line = new CTLine(attributedString);
RectangleF textBounds = line.GetBounds(CTLineBoundsOptions.UseOpticalBounds);
CTRun[] runs = line.GetGlyphRuns();
var lineLength = Polyline2D.Length(x, y);
// set the correct tranformations to draw the resulting paths.
target.Target.CGContext.SaveState();
//target.Target.CGContext.TranslateCTM (xPixels, yPixels);
//target.Target.CGContext.ConcatCTM (new CGAffineTransform (1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f));
foreach (CTRun run in runs)
{
ushort[] glyphs = run.GetGlyphs();
PointF[] positions = run.GetPositions();
float[] characterWidths = new float[glyphs.Length];
float previous = 0;
float textLength = (float)this.FromPixels(_target, _view, positions [positions.Length - 1].X);
if (lineLength > textLength * 1.2f)
{
for (int idx = 0; idx < characterWidths.Length - 1; idx++)
{
characterWidths [idx] = (float)this.FromPixels(_target, _view, positions [idx + 1].X - previous);
previous = positions [idx + 1].X;
}
characterWidths [characterWidths.Length - 1] = characterWidths[characterWidths.Length - 2];
float characterHeight = textBounds.Height;
this.DrawLineTextSegment(target, x, y, glyphs, color, haloColor, haloRadius,
lineLength / 2f, characterWidths, textLength, characterHeight, font);
}
}
target.Target.CGContext.RestoreState();
}
