LazMapViewer: Implement zoomed preview tiles. Patch by Ekkehard Domning. Adapt drawing engines and full demo projects.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@8835 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/lazmapviewer/examples/fulldemo_with_addons/main.lfm

@@ -37,9 +37,9 @@ object MainForm: TMainForm
     Height = 640
     Top = 0
     Width = 275
-    ActivePage = PgData
+    ActivePage = PgConfig
     Align = alRight
-    TabIndex = 0
+    TabIndex = 1
     TabOrder = 1
     object PgData: TTabSheet
       Caption = 'Data'
@@ -875,6 +875,36 @@ object MainForm: TMainForm
         State = cbChecked
         TabOrder = 10
       end
+      object CbPreviewTiles: TCheckBox
+        AnchorSideLeft.Control = CbCyclic
+        AnchorSideTop.Control = CbUseThreads
+        AnchorSideTop.Side = asrCenter
+        Left = 130
+        Height = 19
+        Top = 175
+        Width = 83
+        Caption = 'Preview tiles'
+        Checked = True
+        OnChange = CbPreviewTilesChange
+        State = cbChecked
+        TabOrder = 11
+      end
+      object clbBackColor: TColorButton
+        AnchorSideLeft.Control = CbPreviewTiles
+        AnchorSideTop.Control = CbDoubleBuffer
+        AnchorSideTop.Side = asrCenter
+        Left = 130
+        Height = 25
+        Top = 197
+        Width = 105
+        BorderWidth = 2
+        ButtonColorAutoSize = False
+        ButtonColorSize = 15
+        ButtonColor = clWhite
+        Caption = 'Map backgr.'
+        Margin = 4
+        OnColorChanged = clbBackColorColorChanged
+      end
     end
   end
   object GeoNames: TMVGeoNames

components/lazmapviewer/examples/fulldemo_with_addons/main.pas

@@ -36,6 +36,8 @@ type
     cbPOITextBgColor: TColorBox;
     CbZoomToCursor: TCheckBox;
     CbCyclic: TCheckBox;
+    CbPreviewTiles: TCheckBox;
+    clbBackColor: TColorButton;
     FontDialog: TFontDialog;
     GbCenterCoords: TGroupBox;
     GbScreenSize: TGroupBox;
@@ -83,12 +85,14 @@ type
     procedure CbFoundLocationsDrawItem(Control: TWinControl; Index: Integer;
       ARect: TRect; State: TOwnerDrawState);
     procedure cbPOITextBgColorChange(Sender: TObject);
+    procedure CbPreviewTilesChange(Sender: TObject);
     procedure CbProvidersChange(Sender: TObject);
     procedure CbShowPOIImageChange(Sender: TObject);
     procedure CbUseThreadsChange(Sender: TObject);
     procedure CbDistanceUnitsChange(Sender: TObject);
     procedure CbZoomToCursorChange(Sender: TObject);
     procedure CbCyclicChange(Sender: TObject);
+    procedure clbBackColorColorChanged(Sender: TObject);
     procedure FormCreate(Sender: TObject);
     procedure FormDestroy(Sender: TObject);
     procedure FormShow(Sender: TObject);
@@ -346,6 +350,11 @@ begin
   MapView.POITextBgColor := cbPOITextBgColor.Selected;
 end;
 
+procedure TMainForm.CbPreviewTilesChange(Sender: TObject);
+begin
+  MapView.DrawPreviewTiles := CbPreviewTiles.Checked;
+end;
+
 procedure TMainForm.CbProvidersChange(Sender: TObject);
 begin
   MapView.MapProvider := CbProviders.Text;
@@ -380,6 +389,11 @@ begin
   MapView.Cyclic := CbCyclic.Checked;
 end;
 
+procedure TMainForm.clbBackColorColorChanged(Sender: TObject);
+begin
+  MapView.InactiveColor := clbBackColor.ButtonColor;
+end;
+
 procedure TMainForm.ClearFoundLocations;
 var
   i: Integer;
@@ -420,6 +434,7 @@ begin
   CbUseThreads.Checked := MapView.UseThreads;
   CbDoubleBuffer.Checked := MapView.DoubleBuffered;
   CbPOITextBgColor.Selected := MapView.POITextBgColor;
+  clbBackColor.ButtonColor := MapView.InactiveColor;
 
   InfoPositionLongitude.Caption := '';
   InfoPositionLatitude.Caption := '';
@@ -610,6 +625,8 @@ begin
     pt.Lon := StrToFloatDef(ini.ReadString('MapView', 'Center.Longitude', ''), 0.0, PointFormatSettings);
     pt.Lat := StrToFloatDef(ini.ReadString('MapView', 'Center.Latitude', ''), 0.0, PointFormatSettings);
     MapView.Center := pt;
+    MapView.InactiveColor := ini.ReadInteger('MapView', 'MapBkgrColor', MapView.InactiveColor);
+    clbBackColor.ButtonColor := MapView.InactiveColor;
 
     s := ini.ReadString('MapView', 'DistanceUnits', '');
     if s <> '' then begin
@@ -737,6 +754,7 @@ begin
     ini.WriteInteger('MapView', 'Zoom', MapView.Zoom);
     ini.WriteString('MapView', 'Center.Longitude', FloatToStr(MapView.Center.Lon, PointFormatSettings));
     ini.WriteString('MapView', 'Center.Latitude', FloatToStr(MapView.Center.Lat, PointFormatSettings));
+    ini.WriteInteger('MapView', 'MapBkgrColor', MapView.InactiveColor);
 
     ini.WriteString('MapView', 'DistanceUnits', DistanceUnit_Names[DistanceUnit]);