private LabelMoveData FindMovableItem(int x, int y)
{
// Actually, collision avoidance is turned on for all layers now
// and Labels.Select, Charts.Select return only visible objects
// so it's not possible to have 2 candidate labels for draging
// so we can have much easier code here, but better still to consider
// thу more difficult situation in case somebody will turn off collision
// avoidance form plugin
// 1 - vpAboveAll layers (considered first)
// 0 - above current layer
var data = new LabelMoveData()
{
X = x, Y = y
};
for (int z = 1; z >= 0; z--) // Considering position above the layer and above all layers
{
int layerCount = _map.Layers.Count;
for (int i = layerCount - 1; i >= 0; i--) // we are starting from the layers which were drawn last
{
var layer = _map.Layers[i];
if (layer == null || !layer.IsVector || layer.FeatureSet == null)
{
continue;
}
var fs = layer.FeatureSet;
var env = new Envelope();
env.SetBounds(x, x, y, y);
var position = (VerticalPosition)z;
int chartIndex = FindChart(fs, env, position);
if (chartIndex != -1)
{
data.LayerHandle = layer.Handle;
data.LabelIndex = chartIndex;
data.IsChart = true;
return(data);
}
var info = FindLabel(fs, env, position);
if (info != null)
{
data.LayerHandle = layer.Handle;
data.LabelIndex = info.LabelIndex;
data.PartIndex = info.PartIndex;
data.IsChart = false;
return(data);
}
}
}
return(null);
}
/// <summary>
/// Start the dragging operation.
/// </summary>
private void MapMouseDown(IMuteMap map, MouseEventArgs e)
{
if (!Active)
{
return;
}
var data = FindMovableItem(e.X, e.Y);
if (data == null)
{
return;
}
_currentLabel = data;
var fs = _map.GetFeatureSet(_currentLabel.LayerHandle);
if (fs == null)
{
return;
}
IEnvelope env = null;
if (_currentLabel.IsChart)
{
var chart = fs.Diagrams[_currentLabel.LabelIndex];
env = chart.ScreenExtents;
}
else
{
var label = fs.Labels.Items[_currentLabel.LabelIndex, _currentLabel.PartIndex];
env = label.ScreenExtents;
}
_currentLabel.Rect = env.ToRectangle();
DrawLabelRectangle(_currentLabel.Rect);
}
