/// <summary>
/// Finds the "best" tile from queue
/// 从队列中寻找最佳的瓦片
/// </summary>
public virtual GeoSpatialDownloadRequest GetClosestDownloadRequest()
{
GeoSpatialDownloadRequest closestRequest = null;
float largestArea = float.MinValue;
lock (m_downloadRequests.SyncRoot)
{
foreach (GeoSpatialDownloadRequest curRequest in m_downloadRequests.Values)
{
if (curRequest.IsDownloading)
{
continue;
}
QuadTile qt = curRequest.QuadTile;
if (!m_camera.ViewFrustum.Intersects(qt.BoundingBox))
{
continue;
}
float screenArea = qt.BoundingBox.CalcRelativeScreenArea(m_camera);
if (screenArea > largestArea)
{
largestArea = screenArea;
closestRequest = curRequest;
}
}
}
return(closestRequest);
}
/// <summary>
/// Removes a request from the download queue.
/// 从下载队列中移除一个下载请求
/// </summary>
public virtual void RemoveFromDownloadQueue(GeoSpatialDownloadRequest removeRequest)
{
lock (m_downloadRequests.SyncRoot)
{
QuadTile key = removeRequest.QuadTile;
GeoSpatialDownloadRequest request = (GeoSpatialDownloadRequest)m_downloadRequests[key];
if (request != null)
{
m_downloadRequests.Remove(key);
request.QuadTile.DownloadRequest = null;
}
}
}
/// <summary>
/// 渲染下载进度
/// </summary>
/// <param name="drawArgs"></param>
/// <param name="request"></param>
/// <param name="offset"></param>
public void RenderDownloadProgress(DrawArgs drawArgs, GeoSpatialDownloadRequest request, int offset)
{
int halfIconHeight = 24;
int halfIconWidth = 24;
Vector3 projectedPoint = new Vector3(DrawArgs.ParentControl.Width - halfIconWidth - 10, DrawArgs.ParentControl.Height - 34 - 4 * offset, 0.5f);
// Render progress bar
if (progressBar == null)
{
progressBar = new ProgressBar(40, 4);
}
progressBar.Draw(drawArgs, projectedPoint.X, projectedPoint.Y + 24, request.ProgressPercent, World.Settings.DownloadProgressColor.ToArgb());
DrawArgs.Device.RenderState.ZBufferEnable = true;
// Render server logo
if (ServerLogoFilePath == null)
{
return;
}
if (m_iconTexture == null)
{
m_iconTexture = ImageHelper.LoadIconTexture(ServerLogoFilePath);
}
if (sprite == null)
{
using (Surface s = m_iconTexture.GetSurfaceLevel(0))
{
SurfaceDescription desc = s.Description;
m_spriteSize = new Rectangle(0, 0, desc.Width, desc.Height);
}
this.sprite = new Sprite(DrawArgs.Device);
}
float scaleWidth = (float)2.0f * halfIconWidth / m_spriteSize.Width;
float scaleHeight = (float)2.0f * halfIconHeight / m_spriteSize.Height;
this.sprite.Begin(SpriteFlags.AlphaBlend);
this.sprite.Transform = Matrix.Transformation2D(new Vector2(0.0f, 0.0f), 0.0f, new Vector2(scaleWidth, scaleHeight),
new Vector2(0, 0),
0.0f, new Vector2(projectedPoint.X, projectedPoint.Y));
this.sprite.Draw(m_iconTexture, m_spriteSize,
new Vector3(1.32f * 48, 1.32f * 48, 0), new Vector3(0, 0, 0),
World.Settings.DownloadLogoColor);
this.sprite.End();
}
/// <summary>
/// 添加到下载队列（ZYM:20130706）
/// </summary>
/// <param name="camera"></param>
/// <param name="newRequest"></param>
public virtual void AddToDownloadQueue(CameraBase camera, GeoSpatialDownloadRequest newRequest)
{
QuadTile key = newRequest.QuadTile;
key.IsWaitingForDownload = true;
lock (m_downloadRequests.SyncRoot)
{
if (m_downloadRequests.Contains(key))
{
return;
}
m_downloadRequests.Add(key, newRequest);
if (m_downloadRequests.Count >= m_maxQueueSize)
{
//remove spatially farthest request
GeoSpatialDownloadRequest farthestRequest = null;
Angle curDistance = Angle.Zero;
Angle farthestDistance = Angle.Zero;
foreach (GeoSpatialDownloadRequest curRequest in m_downloadRequests.Values)
{
curDistance = MathEngine.SphericalDistance(
curRequest.QuadTile.CenterLatitude,
curRequest.QuadTile.CenterLongitude,
camera.Latitude,
camera.Longitude);
if (curDistance > farthestDistance)
{
farthestRequest = curRequest;
farthestDistance = curDistance;
}
}
farthestRequest.Dispose();
farthestRequest.QuadTile.DownloadRequest = null;
m_downloadRequests.Remove(farthestRequest.QuadTile);
}
}
ServiceDownloadQueue();
}
