public void DrawCoordinationSystem(ModelViewSurface surface, SKCanvas canvas)
{
float h = surface.ViewHeight / 20;
float w = h / 5;
SKPath arrow = new SKPath();
arrow.MoveTo(-w, -2 * w);
arrow.LineTo(-w, 4 * w);
arrow.LineTo(-2 * w, 4 * w);
arrow.LineTo(0, 6 * w);
arrow.LineTo(2 * w, 4 * w);
arrow.LineTo(w, 4 * w);
arrow.LineTo(w, -2 * w);
arrow.Close();
SKPaint arrowPaint = new SKPaint()
{
Style = SKPaintStyle.StrokeAndFill,
Color = Color.FromRgb(30, 30, 40).ToSKColor(),
IsAntialias = true,
BlendMode = SKBlendMode.Lighten,
StrokeWidth = 1,
TextAlign = SKTextAlign.Center,
TextSize = 2 * w
};
float px = 3 * w;
float py = surface.ViewHeight - 3 * w;
arrow.Transform(SKMatrix.MakeTranslation(px, py));
arrow.Transform(SKMatrix.MakeRotation((float)Math.PI, px, py));
canvas.DrawPath(arrow, arrowPaint);
arrow.Transform(SKMatrix.MakeRotation((float)Math.PI / 2, px, py));
canvas.DrawPath(arrow, arrowPaint);
arrowPaint.Color = Color.White.ToSKColor();
canvas.DrawText("Y", px, py - 8 * w, arrowPaint);
canvas.DrawText("X", px + 8 * w, py + w / 2, arrowPaint);
}
public void DrawAxisText(ModelViewSurface surface, SKCanvas canvas)
{
SKPaint axisPaint = new SKPaint()
{
Style = SKPaintStyle.StrokeAndFill,
Color = Color.LightGray.ToSKColor(),
IsAntialias = true,
BlendMode = SKBlendMode.Lighten,
StrokeWidth = 1,
TextAlign = SKTextAlign.Center,
TextSize = surface.ViewHeight / 75
};
for (float x = gridStartXbig; x < surface.ViewWidth * surface.ScaleFactor; x += ScaledStep * 10)
{
SKPoint pt = IssoConvert.IssoPoint2DToSkPoint(new IssoPoint2D()
{
X = x, Y = surface.Origin.Y
},
surface.ScaleFactor, surface.Origin, surface.ViewHeight);
pt.Y -= axisPaint.TextSize * 2;
canvas.DrawText(x.ToString("F1"), pt, axisPaint);
}
axisPaint.TextAlign = SKTextAlign.Left;
for (float y = gridStartYbig + ScaledStep * 10; y < surface.ViewHeight * surface.ScaleFactor; y += ScaledStep * 10)
{
SKPoint pt = IssoConvert.IssoPoint2DToSkPoint(new IssoPoint2D()
{
X = surface.Origin.X,
Y = y
}, surface.ScaleFactor, surface.Origin, surface.ViewHeight);
pt.X += axisPaint.TextSize;
pt.Y += axisPaint.TextSize / 2;
canvas.DrawText(y.ToString("F1"), pt, axisPaint);
}
}
public void DrawGrid(ModelViewSurface surface, SKCanvas canvas)
{
if (UpdateNeeded)
{
gridBMP = new SKBitmap((int)Math.Round(surface.ViewWidth), (int)Math.Round(surface.ViewHeight));
gridBuffer = new SKCanvas(gridBMP);
float x = surface.Origin.X;
float y = surface.Origin.Y;
// Найдём ближайшее кратное
// Количество крупных и мелких делений сетки всегда примерно определённое.
// Берём ширину окна просмотра и делим её на сто частей
float stepx = surface.ViewWidth / 100;
// Определим, скольки линейным единицам модели равен этот шаг
// И округлим его
ScaledStep = (float)Math.Round(stepx / surface.ScaleFactor, 1);
// Теперь найдём кратное ScaledStep число, ближайшее к surface.Origin
gridStartX = (float)Math.Floor(x / ScaledStep) * ScaledStep;
gridStartY = (float)Math.Floor(y / ScaledStep) * ScaledStep;
if (gridStartX < x)
{
gridStartX += ScaledStep;
}
if (gridStartY < y)
{
gridStartY += ScaledStep;
}
gridStartXbig = (float)Math.Floor(x / (ScaledStep * 10)) * ScaledStep * 10;
gridStartYbig = (float)Math.Floor(y / (ScaledStep * 10)) * ScaledStep * 10;
if (gridStartX < x)
{
gridStartX += ScaledStep;
}
if (gridStartY < y)
{
gridStartY += ScaledStep;
}
if (gridStartXbig < x)
{
gridStartXbig += ScaledStep * 10;
}
if (gridStartYbig < y)
{
gridStartYbig += ScaledStep * 10;
}
// Теперь рисуем. Для крупных и мелких делений - своя структура SKPaint
SKPaint PaintSmall = new SKPaint
{
Style = SKPaintStyle.Stroke,
Color = Color.FromRgb(20, 20, 20).ToSKColor(),
IsAntialias = true,
StrokeWidth = 1
};
SKPaint PaintBig = new SKPaint
{
Style = SKPaintStyle.Stroke,
Color = PaintSmall.Color,
IsAntialias = true,
StrokeWidth = 3
};
SKPoint smallStart = IssoConvert.IssoPoint2DToSkPoint(new IssoPoint2D()
{
X = gridStartX, Y = gridStartY
},
surface.ScaleFactor, surface.Origin, surface.ViewHeight);
SKPoint bigStart = IssoConvert.IssoPoint2DToSkPoint(new IssoPoint2D()
{
X = gridStartXbig, Y = gridStartYbig
},
surface.ScaleFactor, surface.Origin, surface.ViewHeight);
for (x = smallStart.X; x < surface.ViewWidth; x += ScaledStep * surface.ScaleFactor)
{
gridBuffer.DrawLine(x, 0, x, surface.ViewHeight, PaintSmall);
}
for (x = bigStart.X; x < surface.ViewWidth; x += ScaledStep * 10 * surface.ScaleFactor)
{
gridBuffer.DrawLine(x, 0, x, surface.ViewHeight, PaintBig);
}
for (y = smallStart.Y; y > 0; y -= ScaledStep * surface.ScaleFactor)
{
gridBuffer.DrawLine(0, y, surface.ViewWidth, y, PaintSmall);
}
for (y = bigStart.Y; y > 0; y -= ScaledStep * 10 * surface.ScaleFactor)
{
gridBuffer.DrawLine(0, y, surface.ViewWidth, y, PaintBig);
}
DrawCoordinationSystem(surface, gridBuffer);
DrawAxisText(surface, gridBuffer);
UpdateNeeded = false;
}
canvas.DrawBitmap(gridBMP, 0, 0);
}
