/// <summary>
/// Draw the the PlotSurface and contents (axes, drawables, and legend) using the
/// Drawing Context supplied and the bounding rectangle for the PlotSurface to cover
/// </summary>
/// <param name="ctx">The Drawing Context with which to draw.</param>
/// <param name="bounds">The rectangle within which to draw</param>
public void Draw(Context ctx, Rectangle bounds)
{
Point titleOrigin = Point.Zero;
ctx.Save();
// determine font sizes and tick scale factor.
double scale = DetermineScaleFactor(bounds.Width, bounds.Height);
// if there is nothing to plot, draw title and return.
if (drawables.Count == 0)
{
// draw title
//TODO: Title should be centred here - not its origin
Point origin = Point.Zero;
titleOrigin.X = bounds.Width / 2;
titleOrigin.Y = bounds.Height / 2;
DrawTitle(ctx, titleOrigin, scale);
ctx.Restore();
return;
}
// determine the [non physical] axes to draw based on the axis properties set.
Axis XAxis1 = null;
Axis XAxis2 = null;
Axis YAxis1 = null;
Axis YAxis2 = null;
DetermineAxesToDraw(out XAxis1, out XAxis2, out YAxis1, out YAxis2);
// apply scale factor to axes as desired.
if (XAxis1.AutoScaleTicks)
{
XAxis1.TickScale = scale;
}
if (XAxis1.AutoScaleText)
{
XAxis1.FontScale = scale;
}
if (YAxis1.AutoScaleTicks)
{
YAxis1.TickScale = scale;
}
if (YAxis1.AutoScaleText)
{
YAxis1.FontScale = scale;
}
if (XAxis2.AutoScaleTicks)
{
XAxis2.TickScale = scale;
}
if (XAxis2.AutoScaleText)
{
XAxis2.FontScale = scale;
}
if (YAxis2.AutoScaleTicks)
{
YAxis2.TickScale = scale;
}
if (YAxis2.AutoScaleText)
{
YAxis2.FontScale = scale;
}
// determine the default physical positioning of those axes.
PhysicalAxis pXAxis1 = null;
PhysicalAxis pYAxis1 = null;
PhysicalAxis pXAxis2 = null;
PhysicalAxis pYAxis2 = null;
DeterminePhysicalAxesToDraw(
bounds, XAxis1, XAxis2, YAxis1, YAxis2,
out pXAxis1, out pXAxis2, out pYAxis1, out pYAxis2);
double oldXAxis2Height = pXAxis2.PhysicalMin.Y;
// Apply axes constraints
for (int i = 0; i < axesConstraints.Count; ++i)
{
((AxesConstraint)axesConstraints[i]).ApplyConstraint(
pXAxis1, pYAxis1, pXAxis2, pYAxis2);
}
// draw legend if have one.
// Note: this will update axes if necessary.
Point legendPosition = new Point(0, 0);
if (legend != null)
{
legend.UpdateAxesPositions(
pXAxis1, pYAxis1, pXAxis2, pYAxis2,
drawables, scale, Padding, bounds,
out legendPosition);
}
double newXAxis2Height = pXAxis2.PhysicalMin.Y;
double titleExtraOffset = oldXAxis2Height - newXAxis2Height;
// now we are ready to define the clipping region
plotAreaBoundingBoxCache = new Rectangle(
Math.Min(pXAxis1.PhysicalMin.X, pXAxis1.PhysicalMax.X),
Math.Min(pYAxis1.PhysicalMax.Y, pYAxis1.PhysicalMin.Y),
Math.Abs(pXAxis1.PhysicalMax.X - pXAxis1.PhysicalMin.X + 1),
Math.Abs(pYAxis1.PhysicalMin.Y - pYAxis1.PhysicalMax.Y + 1)
);
bbXAxis1Cache = pXAxis1.GetBoundingBox();
bbXAxis2Cache = pXAxis2.GetBoundingBox();
bbYAxis1Cache = pYAxis1.GetBoundingBox();
bbYAxis2Cache = pYAxis2.GetBoundingBox();
Rectangle plotBounds = (Rectangle)plotAreaBoundingBoxCache;
// set the clipping region.. (necessary for zoom)
// Note: although clipping is enforced by the clip region, it is probably more efficient
// for each Drawable to check against the plotBounds and not draw if points are outside.
// This hasn't yet been implemented
ctx.Save();
ctx.Rectangle(plotBounds);
ctx.Clip();
// Fill in the plot background.
if (plotBackImage != null)
{
// Ensure plotBounds has integer size for correct tiling/drawing
plotBounds.Width = Math.Truncate(plotBounds.Width);
plotBounds.Height = Math.Truncate(plotBounds.Height);
ctx.DrawImage(Utils.TiledImage(plotBackImage, plotBounds.Size), plotBounds);
}
else if (plotBackGradient != null)
{
// Scale plotBackGradient to plotBounds
double startX = plotBounds.X + (plotBackGradient.StartPoint.X * plotBounds.Width);
double startY = plotBounds.Y + (plotBackGradient.StartPoint.Y * plotBounds.Height);
double endX = plotBounds.X + (plotBackGradient.EndPoint.X * plotBounds.Width);
double endY = plotBounds.Y + (plotBackGradient.EndPoint.Y * plotBounds.Height);
LinearGradient g = new LinearGradient(startX, startY, endX, endY);
g.AddColorStop(0, plotBackGradient.StartColor);
g.AddColorStop(1, plotBackGradient.EndColor);
ctx.Rectangle(plotBounds);
ctx.Pattern = g;
ctx.Fill();
}
else
{
ctx.Rectangle(plotBounds);
ctx.SetColor(plotBackColor);
ctx.Fill();
}
// draw title at centre of Physical X-axis and at top of plot
titleOrigin.X = (pXAxis2.PhysicalMax.X + pXAxis2.PhysicalMin.X) / 2.0;
titleOrigin.Y = bounds.Top + Padding - titleExtraOffset;
Size s = DrawTitle(ctx, titleOrigin, scale);
bbTitleCache = new Rectangle(titleOrigin.X - s.Width / 2, titleOrigin.Y, s.Width, s.Height);
// draw drawables..
bool legendDrawn = false;
for (int i_o = 0; i_o < ordering.Count; ++i_o)
{
int i = (int)ordering.GetByIndex(i_o);
double zOrder = (double)ordering.GetKey(i_o);
if (zOrder > legendZOrder)
{
// draw legend.
if (!legendDrawn && legend != null)
{
legend.Draw(ctx, legendPosition, drawables, scale);
legendDrawn = true;
}
}
IDrawable drawable = (IDrawable)drawables[i];
XAxisPosition xap = (XAxisPosition)xAxisPositions[i];
YAxisPosition yap = (YAxisPosition)yAxisPositions[i];
PhysicalAxis drawXAxis;
PhysicalAxis drawYAxis;
if (xap == XAxisPosition.Bottom)
{
drawXAxis = pXAxis1;
}
else
{
drawXAxis = pXAxis2;
}
if (yap == YAxisPosition.Left)
{
drawYAxis = pYAxis1;
}
else
{
drawYAxis = pYAxis2;
}
drawable.Draw(ctx, drawXAxis, drawYAxis);
}
if (!legendDrawn && legend != null)
{
legend.Draw(ctx, legendPosition, drawables, scale);
}
ctx.Restore(); // end of clipping region
// cache the physical axes we used on this draw;
pXAxis1Cache = pXAxis1;
pYAxis1Cache = pYAxis1;
pXAxis2Cache = pXAxis2;
pYAxis2Cache = pYAxis2;
// now draw axes.
Rectangle axisBounds;
pXAxis1.Draw(ctx, out axisBounds);
pXAxis2.Draw(ctx, out axisBounds);
pYAxis1.Draw(ctx, out axisBounds);
pYAxis2.Draw(ctx, out axisBounds);
#if DEBUG_BOUNDING_BOXES
ctx.SetColor(Colors.Orange);
ctx.Rectangle((Rectangle)bbXAxis1Cache);
ctx.Rectangle((Rectangle)bbXAxis2Cache);
ctx.Rectangle((Rectangle)bbYAxis1Cache);
ctx.Rectangle((Rectangle)bbYAxis2Cache);
ctx.Stroke();
ctx.SetColor(Colors.Red);
ctx.Rectangle((Rectangle)plotAreaBoundingBoxCache);
ctx.Rectangle((Rectangle)bbTitleCache);
ctx.Stroke();
#endif
ctx.Restore();
}
