/// <summary>
/// Creates the diagonal Guide Paths
/// </summary>
/// <param name="pixel"></param>
private void SuggestGuidePaths(SKPoint pixel)
{
float x = pixel.X;
float y = pixel.Y;
var pathList = new List <BondPath>();
const float len = 200;
const double ang = 0.5235987756; // 30 degrees from horizontal to get 120 deg diagonals for hexagons
var path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x + len * (float)Math.Cos(ang), y + len * (float)Math.Sin(ang));
pathList.Add(path);
path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x + len * (float)Math.Cos(ang), y - len * (float)Math.Sin(ang));
pathList.Add(path);
path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x - len * (float)Math.Cos(ang), y + len * (float)Math.Sin(ang));
pathList.Add(path);
path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x - len * (float)Math.Cos(ang), y - len * (float)Math.Sin(ang));
pathList.Add(path);
guidePaths.Add(pixel, pathList);
}
/// <summary>
/// Creates the vertical and horizontal Guide Paths
/// </summary>
/// <param name="pixel"></param>
private void SuggestAltGuidePaths(SKPoint pixel)
{
float x = pixel.X;
float y = pixel.Y;
var pathList = new List <BondPath>();
const float len = 200;
var path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x, y + len);
pathList.Add(path);
path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x, y - len);
pathList.Add(path);
path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x + len, y);
pathList.Add(path);
path = new BondPath();
path.MoveTo(x, y);
path.LineTo(x - len, y);
pathList.Add(path);
guidePaths[pixel].AddRange(pathList);
}
/// <summary>
/// Processes touch input
/// </summary>
/// <param name="sender"></param>
/// <param name="args"></param>
void TouchEffect_OnTouchAction(object sender, TouchActionEventArgs args)
{
switch (args.Type)
{
// An individual press
// If canvas is blank then it purely suggests the guide paths
// If the canvas is not blank then the touch only registers if it hits on an existing atom
case TouchActionType.Pressed:
if (!inProgressPaths.ContainsKey(args.Id))
{
guidePaths.Clear();
BondPath path = new BondPath();
var pixel = ConvertToPixel(args.Location);
if (completedPaths.Count > 0)
{
foreach (var pth in completedPaths)
{
if (SKPoint.Distance(pth[0], pixel) < 50)
{
pixel = pth[0];
SuggestGuidePaths(pixel);
SuggestAltGuidePaths(pixel);
break;
}
if (SKPoint.Distance(pth.LastPoint, pixel) < 50)
{
pixel = pth.LastPoint;
SuggestGuidePaths(pixel);
SuggestAltGuidePaths(pixel);
break;
}
}
GuidePathTrim(pixel);
}
path.MoveTo(pixel);
inProgressPaths.Add(args.Id, path);
if (completedPaths.Count == 0)
{
SuggestGuidePaths(pixel);
SuggestAltGuidePaths(pixel);
}
canvasView.InvalidateSurface();
}
break;
// Drag the line to the end of the template line and then it becomes a 'completed line'
case TouchActionType.Moved:
if (inProgressPaths.ContainsKey(args.Id))
{
BondPath path = inProgressPaths[args.Id];
var firstPoint = path[0];
path.Rewind();
path.MoveTo(firstPoint);
path.LineTo(ConvertToPixel(args.Location));
if (guidePaths.ContainsKey(firstPoint))
{
BondPath linqPath = guidePaths[firstPoint]
.FirstOrDefault(pth => SKPoint.Distance(pth.LastPoint, path.LastPoint) < 30);
if (linqPath != null)
{
guidePaths.Remove(linqPath[0]);
linqPath.Order = BondOrderFromPicker();
completedPaths.Add(linqPath);
undoStack.Push("path");
MakeNewPathFromPoint(args, linqPath.LastPoint);
SuggestGuidePaths(linqPath.LastPoint);
SuggestAltGuidePaths(linqPath.LastPoint);
GuidePathTrim(linqPath.LastPoint);
}
}
canvasView.InvalidateSurface();
}
break;
case TouchActionType.Released:
if (inProgressPaths.ContainsKey(args.Id))
{
inProgressPaths.Remove(args.Id);
canvasView.InvalidateSurface();
}
break;
case TouchActionType.Cancelled:
if (inProgressPaths.ContainsKey(args.Id))
{
inProgressPaths.Remove(args.Id);
canvasView.InvalidateSurface();
}
break;
}
}