void OnCanvasViewPaintSurface(object sender, SKPaintSurfaceEventArgs args)
{
SKImageInfo info = args.Info;
SKSurface surface = args.Surface;
SKCanvas canvas = surface.Canvas;
canvas.Clear();
// Create an array of points scattered through the page
SKPoint[] points = new SKPoint[10];
for (int i = 0; i < 2; i++)
{
float x = (0.1f + 0.8f * i) * info.Width;
for (int j = 0; j < 5; j++)
{
float y = (0.1f + 0.2f * j) * info.Height;
points[2 * j + i] = new SKPoint(x, y);
}
}
SKPaint paint = new SKPaint
{
Style = SKPaintStyle.Stroke,
Color = SKColors.DarkOrchid,
StrokeWidth = 50,
StrokeCap = GetPickerItem <SKStrokeCap>(strokeCapPicker)
};
// Render the points by calling DrawPoints
SKPointMode pointMode = GetPickerItem <SKPointMode>(pointModePicker);
canvas.DrawPoints(pointMode, points, paint);
}
public void DrawPoints(SKPointMode mode, SKPoint[] points, SKPaint paint)
{
canvas.DrawPoints(mode, points, paint);
if (calculateBounds)
{
displayObject.addBoundingPoints(points);
}
}
public void DrawPoints(SKPointMode mode, SKPoint [] points, SKPaint paint)
{
if (paint == null)
{
throw new ArgumentNullException(nameof(paint));
}
if (points == null)
{
throw new ArgumentNullException(nameof(points));
}
SkiaApi.sk_canvas_draw_points(Handle, mode, (IntPtr)points.Length, points, paint.Handle);
}
public void DrawPoints(SKPointMode mode, SKPoint [] points, SKPaint paint)
{
if (paint == null)
throw new ArgumentNullException (nameof (paint));
if (points == null)
throw new ArgumentNullException (nameof (points));
SkiaApi.sk_canvas_draw_points (Handle, mode, (IntPtr)points.Length, points, paint.Handle);
}
public extern static void sk_canvas_draw_points(sk_canvas_t t, SKPointMode mode, IntPtr count, [In] SKPoint[] points, sk_paint_t paint);
private void OnPaintSurface(object sender, SKPaintSurfaceEventArgs args)
{
// the the canvas and properties
SKImageInfo info = args.Info;
SKSurface surface = args.Surface;
SKCanvas canvas = args.Surface.Canvas;
// get the screen density for scaling
var scale = Resources.DisplayMetrics.Density;
// get the scaled size of the screen in density-indep pixals
// pixals = (dp pixals) * DisplayMetrics.Density
// (dp pixals) = pixals / DisplayMetrics.Density
var scaledSize = new SKSize(info.Width / scale, info.Height / scale);
// handle the device screen density
canvas.Scale(scale);
// make sure the canvas is blank
canvas.Clear(SKColors.White);
// draw some text
var paint = new SKPaint
{
Color = SKColors.Black,
Style = SKPaintStyle.Stroke,
StrokeWidth = 10, //in dp
IsAntialias = true,
};
var paint_red = new SKPaint
{
Style = SKPaintStyle.Stroke,
Color = SKColors.OrangeRed,
StrokeWidth = 10, // in dp
StrokeCap = SKStrokeCap.Butt,
IsAntialias = true,
};
var paint_blue = new SKPaint
{
Style = SKPaintStyle.Stroke,
Color = SKColors.Blue,
StrokeWidth = 35, //in dp
StrokeCap = SKStrokeCap.Round,
IsAntialias = true,
};
// Create an SKPaint object to display the text
var textPaint = new SKPaint
{
Style = SKPaintStyle.Stroke,
FakeBoldText = true,
StrokeWidth = 3f,
Color = SKColors.Blue,
IsAntialias = true,
};
/*
* Coordinates are specified relative to the upper-left corner of the display surface.
* X coordinates increase to the right and Y coordinates increase going down.
* In discussion about graphics, often the mathematical notation (x, y) is used to denote a point.
* The point (0, 0) is the upper-left corner of the display surface and is often called the origin.
*/
// Adjust TextSize property so text is 95% of screen width
// 95% of width * (Height for width ratio)
textPaint.TextSize = 0.15f * scaledSize.Height;
// Find the text bounds
SKRect textBounds = new SKRect();
textPaint.MeasureText(m_ChordName, ref textBounds);
// Calculate offsets to center the text on the screen
float xText = scaledSize.Width / 2 - textBounds.MidX;
float yText = scaledSize.Height / 7.5f - textBounds.MidY;
// And draw the text
canvas.DrawText(m_ChordName, xText, yText, textPaint);
// 10& of height
textPaint.TextSize = 0.1f * scaledSize.Height;
// Find the text bounds
textBounds = new SKRect();
textPaint.MeasureText(m_Dis_ChordPos.ToString(), ref textBounds);
// Calculate offsets to center the text on the screen
xText = scaledSize.Width / 9 - textBounds.MidX;
yText = scaledSize.Height / 2.5f - textBounds.MidY;
// And draw the text
textPaint.Color = SKColors.Black;
textPaint.Style = SKPaintStyle.StrokeAndFill;
canvas.DrawText(m_Dis_ChordPos.ToString(), xText, yText, textPaint);
// divide the scaled size width into 7 spaces
m_space = ((scaledSize.Width) / 7);
m_x_start = m_space + 25;
m_y_start = 200;
m_string_len = (scaledSize.Height - m_y_start / 2);
m_fret_len_space = (m_string_len - 110) / 4;
// Strings
SKPoint[] string_points = new SKPoint[12];
for (int i = 0; i < 2; i++)
{
float y = m_y_start + (m_string_len * i) - (m_fret_len_space * i);
for (int j = 0; j < 6; j++)
{
float x = m_x_start + m_space * j;
string_points[2 * j + i] = new SKPoint(x, y);
}
}
// Render the points by calling DrawPoints
SKPointMode pointMode = SKPointMode.Lines;
canvas.DrawPoints(pointMode, string_points, paint);
// Frets
SKPoint[] fret_points = new SKPoint[10];
for (int i = 0; i < 2; i++)
{
float x = (m_x_start + (5 * m_space * i));
for (int j = 0; j < 5; j++)
{
float y = m_y_start + (m_fret_len_space - 2.5f) * j; // A slight adj with -2.5
fret_points[2 * j + i] = new SKPoint(x, y);
}
}
// Render the points by calling DrawPoints
pointMode = SKPointMode.Lines;
canvas.DrawPoints(pointMode, fret_points, paint);
// Notes on each string
SKPoint[] str_6 = new SKPoint[4];
SKPoint[] str_5 = new SKPoint[4];
SKPoint[] str_4 = new SKPoint[4];
SKPoint[] str_3 = new SKPoint[4];
SKPoint[] str_2 = new SKPoint[4];
SKPoint[] str_1 = new SKPoint[4];
// 6th string E note positions
gen_note_str(out str_6, 6);
// 5th string A note positions
gen_note_str(out str_5, 5);
// 4th string D
gen_note_str(out str_4, 4);
// 3rd string G
gen_note_str(out str_3, 3);
// 2nd string B
gen_note_str(out str_2, 2);
// 1st string E
gen_note_str(out str_1, 1);
// Chord Notes ::::
// Converts the chords frets to actual positions on screen
// subtracts position - 1 to get relative position
// then adds the relative position to an array
SKPoint[] chord_prts = new SKPoint[6];
for (int i = 0; i < m_chord_frets_parsed.Count; i++)
{
// error with larger chords tried m_ChordPos to solve problem
if (!(m_chord_frets_parsed[i] >= 100 | m_chord_frets_parsed[i] <= 0)) //100 represents "^"
{
int parse_temp = m_chord_frets_parsed[i];
parse_temp = parse_temp - 1 - m_ChordPos; // -1 for array
switch (i)
{
case 0:
chord_prts[i] = str_6[parse_temp];
break;
case 1:
chord_prts[i] = str_5[parse_temp];
break;
case 2:
chord_prts[i] = str_4[parse_temp];
break;
case 3:
chord_prts[i] = str_3[parse_temp];
break;
case 4:
chord_prts[i] = str_2[parse_temp];
break;
case 5:
chord_prts[i] = str_1[parse_temp];
break;
default:
System.Console.WriteLine("Exep: More than 6 notes");
break;
}
}
else if (m_chord_frets_parsed[i] <= 100)
{
SKPoint temp_adj = new SKPoint();
SKPath x_path = new SKPath();
switch (i)
{
case 0:
temp_adj = str_6[0];
temp_adj.Y = temp_adj.Y - m_fret_len_space / 2;
x_path = DrawX(temp_adj);
canvas.DrawPath(x_path, paint_red);
break;
case 1:
temp_adj = str_5[0];
temp_adj.Y = temp_adj.Y - m_fret_len_space / 2;
x_path = DrawX(temp_adj);
canvas.DrawPath(x_path, paint_red);
break;
case 2:
temp_adj = str_4[0];
temp_adj.Y = temp_adj.Y - m_fret_len_space / 2;;
x_path = DrawX(temp_adj);
canvas.DrawPath(x_path, paint_red);;
break;
case 3:
temp_adj = str_3[0];
temp_adj.Y = temp_adj.Y - m_fret_len_space / 2;;
x_path = DrawX(temp_adj);
canvas.DrawPath(x_path, paint_red);
break;
case 4:
temp_adj = str_2[0];
temp_adj.Y = temp_adj.Y - m_fret_len_space / 2;;
x_path = DrawX(temp_adj);
canvas.DrawPath(x_path, paint_red);
break;
case 5:
temp_adj = str_1[0];
temp_adj.Y = temp_adj.Y - m_fret_len_space / 2;;
x_path = DrawX(temp_adj);
canvas.DrawPath(x_path, paint_red);
break;
default:
System.Console.WriteLine("Exep: More than 6 notes");
break;
}
chord_prts[i] = new SKPoint(-50, -50); // open str (0) = off screen
}
else
{
chord_prts[i] = new SKPoint(-50, -50); // open str (0) = off screen
}
}
canvas.DrawPoints(SKPointMode.Points, chord_prts, paint_blue);
}
public extern static void sk_canvas_draw_points(sk_canvas_t t, SKPointMode mode, IntPtr count, [In] SKPoint[] points, sk_paint_t paint);