public void Draw(Camera cam, SimTime t)
{
GL.Disable(All.DepthTest);
GL.Enable(All.Texture2D);
_textures.BeginFrame();
_geometries.BeginFrame();
if (MissingTileTexture == 0)
{
using (var img = UIImage.FromFile("MissingTile.png")) {
MissingTileTexture = img.ToGLTexture();
}
}
GL.EnableClientState(All.TextureCoordArray);
GL.EnableClientState(All.NormalArray);
var zoom = cam.Zoom;
if (_lastZoom < 0)
{
_lastZoom = zoom;
}
if (zoom != _lastZoom)
{
_prevZoom = _lastZoom;
_lastZoomFadeTime = t.WallTime;
}
var fadeTime = t.WallTime - _lastZoomFadeTime;
var shouldFade = fadeTime.TotalSeconds < FadeSecs;
var fade = shouldFade ? (float)(fadeTime.TotalSeconds / FadeSecs) : 1.0f;
_lastZoom = zoom;
var centerTile1 = TileName.FromLocation(cam.LookAt, _prevZoom);
var centerTile = TileName.FromLocation(cam.LookAt, zoom);
//
// Draw the tiles
//
if (shouldFade)
{
DrawTiles(cam, centerTile1, 1.0f);
}
DrawTiles(cam, centerTile, fade);
GL.DisableClientState(All.TextureCoordArray);
GL.DisableClientState(All.NormalArray);
GL.Disable(All.Texture2D);
GL.Enable(All.DepthTest);
}
void DrawTiles(Camera cam, TileName centerTile, float alpha)
{
//
// Determine the number of tiles to show
//
int minX = 99999999, minY = 99999999, maxX = 0, maxY = 0;
for (var i = 0; i < cam.ScreenLocations.Length; i++)
{
var loc = cam.ScreenLocations[i];
if (loc != null)
{
var c = TileName.FromLocation(loc, centerTile.Zoom);
minX = Math.Min(c.X, minX);
minY = Math.Min(c.Y, minY);
maxX = Math.Max(c.X, maxX);
maxY = Math.Max(c.Y, maxY);
}
}
minX = Math.Min(centerTile.X, minX);
minY = Math.Min(centerTile.Y, minY);
maxX = Math.Max(centerTile.X, maxX);
maxY = Math.Max(centerTile.Y, maxY);
minX -= 1;
minY -= 1;
maxX += 1;
maxY += 1;
//
// Draw them
//
var nd = 0;
var tile = new TileName()
{
Zoom = centerTile.Zoom
};
var n = (int)Math.Pow(2, tile.Zoom);
foreach (var p in RenderOrder)
{
tile.X = centerTile.X + p.X;
tile.Y = centerTile.Y + p.Y;
while (tile.X < 0)
{
tile.X += n;
}
while (tile.Y < 0)
{
tile.Y += n;
}
while (tile.X >= n)
{
tile.X -= n;
}
while (tile.Y >= n)
{
tile.Y -= n;
}
if (tile.X < minX || tile.Y < minY)
{
continue;
}
if (tile.X > maxX || tile.Y > maxY)
{
continue;
}
DrawTile(tile, alpha);
nd++;
}
}