private static (int x, int y) GetCellCenter(HexMaze maze, Cell cell, int halfHeight, int xOffset)
{
var(row, column) = maze.GetPositionOfCell(cell);
var centerX = (column * (CornerRadius - xOffset) * 2) + (CornerRadius / 2) + Margin;
var centerY = (row * halfHeight * 2) + halfHeight + Margin;
if (column % 2 == 1)
{
centerY += halfHeight;
}
return(centerX, centerY);
}
public static SKImage RenderWithSkia(this HexMaze maze,
RenderOptions renderOptions,
DistanceInfo distanceInfo,
ShortestPathInfo shortestPathInfo)
{
if (maze == null)
{
throw new ArgumentNullException(nameof(maze));
}
renderOptions = renderOptions ?? new RenderOptions();
var rightCorner = GetCoords(CornerRadius, 0);
var bottomRightCorner = GetCoords(CornerRadius, 60);
var bottomLeftCorner = GetCoords(CornerRadius, 120);
var leftCorner = GetCoords(CornerRadius, 180);
var topLeftCorner = GetCoords(CornerRadius, 240);
var topRightCorner = GetCoords(CornerRadius, 300);
var halfHeight = (int)Math.Abs(topRightCorner.y);
var xOffset = (int)(Math.Cos(30) * (halfHeight * 2));
var imageWidth = ((CornerRadius - xOffset) * 2 * maze.ColumnCount) + (Margin * 2);
var imageHeight = (halfHeight * 2 * maze.RowCount) + (Margin * 2) + halfHeight;
var imageInfo = new SKImageInfo(imageWidth, imageHeight, SKColorType.Rgba8888, SKAlphaType.Premul);
using (var surface = SKSurface.Create(imageInfo))
{
surface.Canvas.Clear(SKColors.Black);
var whitePaint = new SKPaint {
Color = SKColors.White, StrokeWidth = CellLineWidth, TextAlign = SKTextAlign.Center
};
var startPaint = new SKPaint {
Color = SKColors.Green, StrokeWidth = 1, TextAlign = SKTextAlign.Center
};
var finishPaint = new SKPaint {
Color = SKColors.Red, StrokeWidth = 1, TextAlign = SKTextAlign.Center
};
var pathPaint = new SKPaint {
Color = SKColors.Yellow, StrokeWidth = 1, TextAlign = SKTextAlign.Center
};
foreach (var cell in maze.AllCells)
{
var cellCenter = GetCellCenter(maze, cell, halfHeight, xOffset);
var corners = new[]
{
new SKPoint(rightCorner.x + cellCenter.x, rightCorner.y + cellCenter.y),
new SKPoint(bottomRightCorner.x + cellCenter.x, bottomRightCorner.y + cellCenter.y),
new SKPoint(bottomLeftCorner.x + cellCenter.x, bottomLeftCorner.y + cellCenter.y),
new SKPoint(leftCorner.x + cellCenter.x, leftCorner.y + cellCenter.y),
new SKPoint(topLeftCorner.x + cellCenter.x, topLeftCorner.y + cellCenter.y),
new SKPoint(topRightCorner.x + cellCenter.x, topRightCorner.y + cellCenter.y),
};
// All walls starting from bottom right and going clockwise
var isWallOpen = new[] { false, false, false, false, false, false };
foreach (var cellWall in cell.CellWalls)
{
if (cellWall.IsPassable)
{
var otherCellCenter = GetCellCenter(maze, cellWall.GetOtherCell(cell), halfHeight, xOffset);
var angle = GetNormalizedDegreesToCell(cellCenter, otherCellCenter);
var index = angle / 60;
isWallOpen[index] = true;
}
}
if (renderOptions.ShowGradientOfDistanceFromStart)
{
var finishingCellDistance = distanceInfo.DistanceFromStartMap[distanceInfo.FarthestCell];
var currentCellDistance = distanceInfo.DistanceFromStartMap[cell];
var intensity = (byte)(255 * (currentCellDistance / (decimal)finishingCellDistance));
var color = new SKColor(0, 0, intensity);
var paint = new SKPaint {
Color = color, Style = SKPaintStyle.Fill
};
var path = new SKPath();
path.MoveTo(corners[0]);
path.LineTo(corners[1]);
path.LineTo(corners[2]);
path.LineTo(corners[3]);
path.LineTo(corners[4]);
path.LineTo(corners[5]);
path.LineTo(corners[0]);
surface.Canvas.DrawPath(path, paint);
}
for (var x = 0; x < isWallOpen.Length; x++)
{
if (!isWallOpen[x])
{
var first = corners[x];
var second = corners[x < 5 ? x + 1 : 0];
surface.Canvas.DrawLine(first, second, whitePaint);
}
}
if (renderOptions.HighlightShortestPath && shortestPathInfo.IsCellInPath(cell))
{
var paint = cell == maze.StartingCell ? startPaint
: cell == maze.FinishingCell ? finishPaint
: pathPaint;
var distance = distanceInfo.DistanceFromStartMap[cell];
surface.Canvas.DrawText(distance.ToString(), cellCenter.x, cellCenter.y + halfHeight / 2, paint);
}
else if (renderOptions.ShowAllDistances && distanceInfo.DistanceFromStartMap.ContainsKey(cell))
{
var distance = distanceInfo.DistanceFromStartMap[cell];
surface.Canvas.DrawText(distance.ToString(), cellCenter.x, cellCenter.y + halfHeight / 2, whitePaint);
}
else if (cell == maze.StartingCell)
{
surface.Canvas.DrawText("S", cellCenter.x, cellCenter.y + halfHeight / 2, startPaint);
}
else if (cell == maze.FinishingCell)
{
surface.Canvas.DrawText("E", cellCenter.x, cellCenter.y + halfHeight / 2, finishPaint);
}
}
return(surface.Snapshot());
}
}