private void DrawFeatures(MapArgs e, IEnumerable<int> indices)
{
Graphics g;
if (e.Device != null)
{
g = e.Device; // A device on the MapArgs is optional, but overrides the normal buffering behaviors.
}
else
{
g = Graphics.FromImage(_backBuffer);
}
// Only draw features that are currently visible.
Extent drawExtents = new Extent(e.PixelToProj(_drawingBounds));
double minX = e.MinX;
double maxY = e.MaxY;
double dx = e.Dx;
double dy = e.Dy;
if(DrawnStatesNeeded)
{
FastDrawnState[] states = DrawnStates;
for (int selectState = 0; selectState < 2; selectState++)
{
foreach (ILineCategory category in Symbology.Categories)
{
// Define the symbology based on the category and selection state
ILineSymbolizer ls = category.Symbolizer;
if (selectState == SELECTED) ls = category.SelectionSymbolizer;
if (ls.Smoothing)
{
g.SmoothingMode = SmoothingMode.AntiAlias;
}
else
{
g.SmoothingMode = SmoothingMode.None;
}
// Determine the subset of the specified features that are visible and match the category
ILineCategory lineCategory = category;
int i = selectState;
Func<FastDrawnState, bool> isMember = state =>
state.Category == lineCategory &&
state.Selected == (i == 1) &&
state.Visible == true;
var drawnFeatures = from feature in indices
where isMember(states[feature])
select feature;
GraphicsPath graphPath = new GraphicsPath();
foreach (int shp in drawnFeatures)
{
ShapeRange shape = DataSet.ShapeIndices[shp];
if (drawExtents.Contains(shape.Extent))
{
// This optimization only works if we are zoomed out far enough
// that the whole linestring fits in the short integer
// drawing window. Otherwise, we need to crop the line.
FastBuildLine(graphPath, DataSet.Vertex, shape, minX, maxY, dx, dy);
}
else
{
for (int iPart = 0; iPart < shape.Parts.Count; iPart++)
{
IBasicGeometry geom = DataSet.GetFeature(shp).GetBasicGeometryN(iPart);
if (drawExtents.Contains(shape.Extent) == false)
{
geom = e.GeographicExtents.Intersection(geom);
}
// Cropped geometries can be either linestrings or multi-linestrings
IBasicLineString bls = geom as IBasicLineString;
if (bls != null)
{
// the result is definitely in the linestring category
BuildLineString(graphPath, bls, minX, maxY, dx, dy);
}
else
{
IMultiLineString intersect = geom as MultiLineString;
if (intersect == null) continue;
for (int iLine = 0; iLine < intersect.NumGeometries; iLine++)
{
BuildLineString(graphPath, intersect.GetBasicGeometryN(iLine) as IBasicLineString, minX, maxY, dx, dy);
}
}
}
}
}
double scale = 1;
if (ls.ScaleMode == ScaleModes.Geographic)
{
scale = e.ImageRectangle.Width / e.GeographicExtents.Width;
}
foreach (IStroke stroke in ls.Strokes)
{
stroke.DrawPath(g, graphPath, scale);
}
graphPath.Dispose();
}
}
}
else
{
// Selection state is disabled
// Category is only the very first category
ILineCategory category = Symbology.Categories[0];
ILineSymbolizer ls = category.Symbolizer;
if (ls.Smoothing)
{
g.SmoothingMode = SmoothingMode.AntiAlias;
}
else
{
g.SmoothingMode = SmoothingMode.None;
}
// Determine the subset of the specified features that are visible and match the category
ILineCategory lineCategory = category;
GraphicsPath graphPath = new GraphicsPath();
foreach (int shp in indices)
{
ShapeRange shape = DataSet.ShapeIndices[shp];
if (drawExtents.Contains(shape.Extent))
{
// This optimization only works if we are zoomed out far enough
// that the whole linestring fits in the short integer
// drawing window. Otherwise, we need to crop the line.
FastBuildLine(graphPath, DataSet.Vertex, shape, minX, maxY, dx, dy);
}
else
{
for (int iPart = 0; iPart < shape.Parts.Count; iPart++)
{
IBasicGeometry geom = DataSet.GetFeature(shp).GetBasicGeometryN(iPart);
if (drawExtents.Contains(shape.Extent) == false)
{
geom = e.GeographicExtents.Intersection(geom);
}
// Cropped geometries can be either linestrings or multi-linestrings
IBasicLineString bls = geom as IBasicLineString;
if (bls != null)
{
// the result is definitely in the linestring category
BuildLineString(graphPath, bls, minX, maxY, dx, dy);
}
else
{
IMultiLineString intersect = geom as MultiLineString;
if (intersect == null) continue;
for (int iLine = 0; iLine < intersect.NumGeometries; iLine++)
{
BuildLineString(graphPath, intersect.GetBasicGeometryN(iLine) as IBasicLineString, minX, maxY, dx, dy);
}
}
}
}
}
double scale = 1;
if (ls.ScaleMode == ScaleModes.Geographic)
{
scale = e.ImageRectangle.Width / e.GeographicExtents.Width;
}
foreach (IStroke stroke in ls.Strokes)
{
stroke.DrawPath(g, graphPath, scale);
}
graphPath.Dispose();
}
if (e.Device == null) g.Dispose();
}
private void BuildPaths(MapArgs e, IEnumerable<int> indices, out List<GraphicsPath> paths)
{
paths = new List<GraphicsPath>();
Extent drawExtents = new Extent(e.PixelToProj(_drawingBounds));
Dictionary<FastDrawnState, GraphicsPath> borders = new Dictionary<FastDrawnState, GraphicsPath>();
for (int selectState = 0; selectState < 2; selectState++)
{
foreach (IPolygonCategory category in Symbology.Categories)
{
FastDrawnState state = new FastDrawnState(selectState == 1, category);
GraphicsPath border = new GraphicsPath();
borders.Add(state, border);
paths.Add(border);
}
}
List<ShapeRange> shapes = DataSet.ShapeIndices;
double[] vertices = DataSet.Vertex;
if(!DrawnStatesNeeded)
{
FastDrawnState state = new FastDrawnState(false, Symbology.Categories[0]);
foreach (int shp in indices)
{
ShapeRange shape = shapes[shp];
if (!shape.Extent.Intersects(e.GeographicExtents)) continue;
if(shp >= shapes.Count) continue;
if (!borders.ContainsKey(state)) continue;
if (drawExtents.Contains(shape.Extent))
{
BuildPolygon(vertices, shapes[shp], borders[state], e, false);
}
else
{
BuildPolygon(vertices, shapes[shp], borders[state], e, true);
}
}
}
else
{
FastDrawnState[] states = DrawnStates;
foreach (int shp in indices)
{
if (shp >= shapes.Count) continue;
if (shp >= states.Length)
{
AssignFastDrawnStates();
states = DrawnStates;
}
if (states[shp].Visible == false) continue;
ShapeRange shape = shapes[shp];
if (!shape.Extent.Intersects(e.GeographicExtents)) continue;
if (drawExtents.Contains(shape.Extent))
{
FastDrawnState state = states[shp];
if (!borders.ContainsKey(state)) continue;
BuildPolygon(vertices, shapes[shp], borders[state], e, false);
}
else
{
FastDrawnState state = states[shp];
if (!borders.ContainsKey(state)) continue;
BuildPolygon(vertices, shapes[shp], borders[state], e, true);
}
}
}
}