LazMapViewer: Extend fulldemo to show how a map can be printed.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@8273 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/lazmapviewer/examples/fulldemo/MapViewer_Demo.lpi

@@ -25,13 +25,16 @@
     <RunParams>
       <FormatVersion Value="2"/>
     </RunParams>
-    <RequiredPackages Count="2">
+    <RequiredPackages Count="3">
       <Item1>
-        <PackageName Value="lazMapViewerPkg"/>
+        <PackageName Value="Printer4Lazarus"/>
       </Item1>
       <Item2>
-        <PackageName Value="LCL"/>
+        <PackageName Value="lazMapViewerPkg"/>
       </Item2>
+      <Item3>
+        <PackageName Value="LCL"/>
+      </Item3>
     </RequiredPackages>
     <Units Count="5">
       <Unit0>

components/lazmapviewer/examples/fulldemo/MapViewer_Demo.lpr

@@ -5,7 +5,7 @@ program MapViewer_Demo;
 uses
   {$IFDEF UNIX}cthreads,{$ENDIF}
   Interfaces, // this includes the LCL widgetset
-  Forms, Main, gpslistform, globals, gpsptform
+  Forms, printer4lazarus, Main, gpslistform, globals, gpsptform
   { you can add units after this };
 
 {$R *.res}

components/lazmapviewer/examples/fulldemo/main.lfm

@@ -536,6 +536,22 @@ object MainForm: TMainForm
         OnClick = BtnLoadGPXFileClick
         TabOrder = 8
       end
+      object BtnPrintMap: TButton
+        AnchorSideLeft.Control = BtnSaveToFile
+        AnchorSideTop.Control = BtnSaveToFile
+        AnchorSideTop.Side = asrBottom
+        AnchorSideRight.Control = BtnSaveToFile
+        AnchorSideRight.Side = asrBottom
+        Left = 6
+        Height = 25
+        Top = 550
+        Width = 110
+        Anchors = [akTop, akLeft, akRight]
+        BorderSpacing.Top = 8
+        Caption = 'Print...'
+        OnClick = BtnPrintMapClick
+        TabOrder = 9
+      end
     end
     object PgConfig: TTabSheet
       Caption = 'Config'
@@ -1255,4 +1271,8 @@ object MainForm: TMainForm
       69754D32C924FBBF68FF0B9EFE66B6
     }
   end
+  object PrintDialog1: TPrintDialog
+    Left = 552
+    Top = 567
+  end
 end

components/lazmapviewer/examples/fulldemo/main.pas

@@ -6,7 +6,7 @@ interface
 
 uses
   Classes, SysUtils, Types, Forms, Controls, Graphics, Dialogs,
-  ExtCtrls, StdCtrls, ComCtrls, Buttons, IntfGraphics, ColorBox,
+  ExtCtrls, StdCtrls, ComCtrls, Buttons, IntfGraphics, ColorBox, PrintersDlgs,
   mvGeoNames, mvMapViewer, mvTypes, mvGpsObj, mvDrawingEngine;
 
 type
@@ -21,6 +21,7 @@ type
     BtnSaveToFile: TButton;
     BtnLoadGPXFile: TButton;
     BtnPOITextFont: TButton;
+    BtnPrintMap: TButton;
     CbDoubleBuffer: TCheckBox;
     CbFoundLocations: TComboBox;
     CbLocations: TComboBox;
@@ -63,10 +64,12 @@ type
     PgData: TTabSheet;
     PgConfig: TTabSheet;
     POIImages: TImageList;
+    PrintDialog1: TPrintDialog;
     rgPOIMode: TRadioGroup;
     ZoomTrackBar: TTrackBar;
     procedure BtnGoToClick(Sender: TObject);
     procedure BtnLoadGPXFileClick(Sender: TObject);
+    procedure BtnPrintMapClick(Sender: TObject);
     procedure BtnSearchClick(Sender: TObject);
     procedure BtnGPSPointsClick(Sender: TObject);
     procedure BtnSaveToFileClick(Sender: TObject);
@@ -122,6 +125,7 @@ implementation
 
 uses
   LCLType, IniFiles, Math, FPCanvas, FPImage, GraphType,
+  Printers, OSPrinters,
   mvEngine, mvGPX,
   globals, gpsPtForm, gpslistform;
 
@@ -233,6 +237,84 @@ begin
   end;
 end;
 
+procedure TMainForm.BtnPrintMapClick(Sender: TObject);
+const
+  INCH = 25.4;         // 1" = 25.4 mm
+  HOR_MARGIN = 10.0;   // mm
+  VERT_MARGIN = 10.0;  // mm
+  
+  function px2mm(px, ppi: Integer): Double;
+  begin
+    Result := px / ppi * INCH;
+  end;
+  
+  function mm2px(mm: Double; ppi: Integer): Integer;
+  begin
+    Result := round(mm / INCH * ppi);
+  end;
+  
+var
+  bmp: TBitmap;
+  PrintedRect: TRect;
+  aspectRatio_map: Double;
+  aspectRatio_page: Double;
+  mapWidth_mm: Double;
+  mapHeight_mm: Double;
+  pageWidth_mm: Double;
+  pageHeight_mm: Double;
+  printedWidth_mm: Double;
+  printedHeight_mm: Double;
+  factor: Double;
+begin
+  if PrintDialog1.Execute then
+  begin
+    Printer.Orientation := poPortrait;
+    
+    // Scale map such that it fits into the width of the printer paper with
+    // a margin at all sides
+    mapWidth_mm := px2mm(MapView.Width, ScreenInfo.PixelsPerInchX);
+    mapHeight_mm := px2mm(MapView.Height, ScreenInfo.PixelsPerInchY);
+    pageWidth_mm := px2mm(Printer.PageWidth, Printer.XDPI) - 2*HOR_MARGIN;
+    pageHeight_mm := px2mm(Printer.PageHeight, Printer.YDPI) - 2*VERT_MARGIN;
+    aspectRatio_map := mapHeight_mm / mapWidth_mm;
+    aspectRatio_page := pageHeight_mm / pageWidth_mm;
+    if aspectRatio_Map > aspectRatio_page then
+    begin
+      factor := pageHeight_mm / mapHeight_mm;
+      printedWidth_mm := mapWidth_mm * factor;
+      printedHeight_mm := pageHeight_mm;
+    end else 
+    begin
+      factor := pageWidth_mm / mapWidth_mm;
+      printedWidth_mm := pageWidth_mm;
+      printedHeight_mm := mapHeight_mm * factor;
+    end;
+    // Calculate size of the output rectangle (on paper).
+    PrintedRect := Rect(0, 0, mm2px(printedWidth_mm, Printer.XDPI), mm2px(printedHeight_mm, Printer.YDPI));
+    // Center output rectangle horizontally on page
+    OffsetRect(PrintedRect, mm2px(HOR_MARGIN + (pageWidth_mm-printedWidth_mm) / 2 , Printer.XDPI), mm2px(VERT_MARGIN, Printer.YDPI));
+
+    // Begin printing
+    Printer.BeginDoc;
+    try
+      // Catch the displayed images as a bitmap.
+      bmp := TBitmap.Create;
+      try
+        bmp.SetSize(MapView.Width, MapView.Height);
+        MapView.DrawingEngine.PaintToCanvas(bmp.Canvas);
+  
+        // Stretch-draw the map image to the output rectangle on the printer. 
+        Printer.Canvas.StretchDraw(PrintedRect, bmp);
+      finally
+        bmp.Free;
+      end;
+        
+    finally
+      Printer.EndDoc;
+    end;
+  end;
+end;
+
 procedure TMainForm.BtnSaveToFileClick(Sender: TObject);
 begin
   MapView.SaveToFile(TPortableNetworkGraphic, 'mapview.png');