LazMapViewer: Fix incorrect painting of stretched and missing tiles when Cyclic is true.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@9680 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/lazmapviewer/source/mvcache.pas

@@ -498,7 +498,7 @@ end;
   the rectangle coordinates to get an upscaled preview of the originally
   requested tile. The function returns true in this case.
   If the requested tile already is in the cache, or no containing tile is found
-  the function returns false indicating that not preview image must be
+  the function returns false indicating that no preview image must be
   generated. }
 function TPictureCache.GetPreviewFromCache(const MapProvider: TMapProvider;
   var TileId: TTileId; out ARect: TRect): boolean;

components/lazmapviewer/source/mvengine.pas

@@ -122,7 +122,7 @@ type
       procedure CalculateWin(var AWin: TMapWindow);
       function DegreesToPixelsEPSG3395(const AWin: TMapWindow; APt: TRealPoint): TPoint;
       function DegreesToPixelsEPSG3857(const AWin: TMapWindow; APt: TRealPoint): TPoint;
-      procedure Redraw(const aWin: TMapWindow; const paintOnly: Boolean = False);
+      procedure Redraw(const aWin: TMapWindow; const PaintOnly: Boolean = False);
       function CalculateVisibleTiles(const aWin: TMapWindow; out Area: TArea): Boolean;
       function IsCurrentWin(const aWin: TMapWindow) : boolean;
     protected
@@ -132,7 +132,7 @@ type
       procedure evDownload(Data: TObject; Job: TJob);
       procedure TileDownloaded(Data: PtrInt);
       procedure EraseBackground(const R: TRect);
-      procedure DrawTileFromCache(constref ATile: TTileId; constref AWin: TMapWindow);
+      procedure DrawTileFromCache(constref ATile: TTileId; constref AWin: TMapWindow; out FoundInCache: Boolean);
       procedure DrawStretchedTile(const TileId: TTileID; X, Y: Integer; TileImg: TPictureCacheItem; const R: TRect);
       Procedure DrawTile(const TileId: TTileId; X,Y: integer; TileImg: TPictureCacheItem);
       Procedure DoDrag(Sender: TDragObj);
@@ -1089,12 +1089,13 @@ begin
 end;
 
 procedure TMapViewerEngine.Redraw(const aWin: TMapWindow;
-  const paintOnly: Boolean);
+  const PaintOnly: Boolean);
 var
   TilesVis: TArea;
   x, y, px, py: Integer;
   iTile, numTiles, XShift: Integer;
   Tiles: TTileIdArray = nil;
+  foundInCache: Boolean;
   tile: TTileID;
   previewDrawn: Boolean;
   previewImg: TPictureCacheItem;
@@ -1105,8 +1106,8 @@ var
     lTile: TEnvTile;
     lJob: TEventJob;
   begin
-    lTile:=TEnvTile.Create(Tiles[iTile], aWin);
+    lTile := TEnvTile.Create(Tiles[iTile], aWin);
-    lJob := TEventJob.Create(@evDownload, lTile, False,                                    // owns data
+    lJob := TEventJob.Create(@evDownload, lTile, False,            // owns data
       GetTileName(Tiles[iTile]));
     if not Queue.AddUniqueJob(lJob, Self) then
     begin
@@ -1159,11 +1160,12 @@ begin
 
   if not CalculateVisibleTiles(AWin, TilesVis) then
     EraseAround;
+
   SetLength(Tiles, (TilesVis.Bottom - TilesVis.Top + 1) * (TilesVis.Right - TilesVis.Left + 1));
   iTile := Low(Tiles);
   numTiles := 1 shl AWin.Zoom;
   XShift := IfThen(aWin.X > 0, numTiles - aWin.X div TileSize.CX - 1, 0);
-  for y := TilesVis.Top to TilesVis.Bottom do
+  for Y := TilesVis.Top to TilesVis.Bottom do
     for X := TilesVis.Left to TilesVis.Right do
     begin
       if FCyclic then
@@ -1177,6 +1179,14 @@ begin
       Tiles[iTile].Y := Y;
       Tiles[iTile].Z := AWin.Zoom;
 
+      DrawTileFromCache(Tiles[iTile], AWin, foundInCache);
+      if (not foundInCache) and (not PaintOnly) and IsValidTile(AWin, Tiles[iTile]) then
+      begin
+        AddJob;
+        inc(iTile);
+      end;
+
+              (*
       if Cache.InCache(AWin.MapProvider, Tiles[iTile]) then
         DrawTileFromCache(Tiles[iTile], AWin)
       else
@@ -1202,12 +1212,15 @@ begin
         if not previewDrawn then
           DrawTile(Tiles[iTile], px, py, nil);  // Draw blank tile if preview cannot be generated
 
+
+          // !!!!!!!!!!!!!!!!!!!!!!
         if not paintOnly and IsValidTile(AWin, Tiles[iTile]) then
         begin
           AddJob;
           inc(iTile);
         end;
       end;
+  *)
     end;
   SetLength(Tiles, iTile);
 end;
@@ -1416,47 +1429,83 @@ end;
 procedure TMapViewerEngine.EraseBackground(const R: TRect);
 begin
   if Assigned(FOnEraseBackground) then
-      FOnEraseBackground(R);
+    FOnEraseBackground(R);
 end;
 
-procedure TMapViewerEngine.DrawTileFromCache(constref ATile: TTileId; constref
+procedure TMapViewerEngine.DrawTileFromCache(constref ATile: TTileID;
-  AWin: TMapWindow);
+  constref AWin: TMapWindow; out FoundInCache: Boolean);
 var
   img: TPictureCacheItem;
-  X, Y: integer;
+  X, Y: Integer;
-  worldWidth : Integer;
+  worldWidth: Integer;
-  numTiles : Integer;
+  numTiles: Integer;
-  baseX : Integer;
+  baseX: Integer;
-begin
+  tile: TTileID;
-  if IsCurrentWin(AWin)then
+  R: TRect;
+  normalDraw: Boolean = true;
+
+  procedure DrawTheTile(ATileID: TTileID; X, Y: Integer; AImg: TPictureCacheItem);
   begin
-     Cache.GetFromCache(AWin.MapProvider, ATile, img);
+    if normalDraw then
-     Y := AWin.Y + ATile.Y * TileSize.CY; // begin of Y
+      DrawTile(ATileID, X, Y, AImg)  // Covers the "missing tile" case when AImg = nil
-     if Cyclic then
+    else
-     begin
+      DrawStretchedTile(ATileID, X, Y, AImg, R);
-       baseX := AWin.X + ATile.X * TileSize.CX; // begin of X
-       numTiles := 1 shl AWin.Zoom;
-       worldWidth := numTiles * TileSize.CX;
-       // From the center to the left (western) hemisphere
-       X := baseX;
-       while (X + TileSize.CX >= 0) do
-       begin
-         DrawTile(ATile, X, Y, img);
-         X := X - worldWidth;
-       end;
-       // From the center to the right (eastern) hemisphere
-       X := baseX + worldWidth;
-       while ((X - TileSize.CX) <= AWin.Width) do
-       begin
-         DrawTile(ATile, X, Y, img);
-         X := X + worldWidth;
-       end;
-     end else
-     begin
-       X := AWin.X + ATile.X * TileSize.CX; // begin of X
-       DrawTile(ATile, X, Y, img);
-     end;
   end;
+
+begin
+  if not IsCurrentWin(AWin) then
+    exit;
+
+  // When no cache image can be found (img = nil) we will have to draw a "missing tile"
+  img := nil;
+  FoundInCache := false;
+
+  if Cache.InCache(AWin.MapProvider, ATile) then
+  begin
+    // Image is found in cache: Load it into "img". It can be drawn directly.
+    Cache.GetFromCache(AWin.MapProvider, ATile, img);
+    FoundInCache := true;
+  end else
+  if FDrawPreviewTiles then
+  begin
+    // Image is not found in cache, but there is another one which can be
+    // scaled to fit. Find the cache parameters for this image.
+    tile := ATile;
+    if Cache.GetPreviewFromCache(AWin.MapProvider, tile, R) then
+    begin
+      // Load cache image into "img". It must be stretch-drawn.
+      Cache.GetFromCache(AWin.MapProvider, tile, img);
+      normalDraw := false;
+    end;
+  end;
+
+  X := AWin.X + ATile.X * TileSize.CX; // begin of X
+  Y := AWin.Y + ATile.Y * TileSize.CY; // begin of Y
+
+  if Cyclic then
+  begin
+    baseX := X;
+    numTiles := 1 shl AWin.Zoom;
+    worldWidth := numTiles * TileSize.CX;
+
+    // Center, plus western hemisphere (left)
+    X := baseX;
+    while (X + TileSize.CX >= 0) do
+    begin
+      DrawTheTile(ATile, X, Y, img);
+      X := X - worldWidth;
+    end;
+
+    // From the center to the right (eastern) hemisphere
+    X := baseX + worldWidth;
+    while (X <= AWin.Width) do
+    begin
+      DrawTheTile(ATile, X, Y, img);
+      X := X + worldWidth;
+    end;
+  end
+  else
+    DrawTheTile(ATile, X, Y, img);
 end;
 
 function TMapViewerEngine.ValidProvider(const AProvider: String): Boolean;

components/lazmapviewer/source/mvmapviewer.pas

@@ -3098,7 +3098,7 @@ procedure TMapView.Paint;
 const
   FREE_DRAG = 0; //(TILE_SIZE * TILE_SIZE) div 4;
 
-  procedure DrawCenter;
+  procedure DrawCenter;  deprecated 'Use plugin';
   var
     C: TPoint;
   begin
@@ -3136,7 +3136,7 @@ const
       FAfterDrawObjectsEvent(Self);
 
     DrawingEngine.PaintToCanvas(Canvas);
-    if DebugTiles then
+    if DebugTiles then     // DebugTiles is deprecated
       DrawCenter;
 
     GetPluginManager.AfterPaint(Self);
@@ -3154,7 +3154,7 @@ const
     begin
       DrawingEngine.PaintToCanvas(Canvas);
       DrawingEngine.PaintToCanvas(Canvas, O);
-      if DebugTiles then
+      if DebugTiles then         // DebugTiles is deprecated
         DrawCenter;
     end
     else
@@ -3681,7 +3681,6 @@ begin
     DrawingEngine.FillPixels(ARect.Left, ARect.Top, ARect.Right, ARect.Bottom, InactiveColor);
 end;
 
-
 procedure TMapView.DoDrawTileInfo(const TileID: TTileID; X, Y: Integer);
 begin
   DrawingEngine.PenColor := clGray;