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LazMapViewer: Fix grid plugin hanging when width of a cyclic map is reduced below 360°.

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git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@9626 8e941d3f-bd1b-0410-a28a-d453659cc2b4
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wp_xxyyzz 2025-02-12 00:15:42 +00:00
parent c6d652e51d
commit b240deb779
1 changed files with 11 additions and 3 deletions
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14
components/lazmapviewer/source/addons/plugins/grids/mvmapgridplugin.pas
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@ -8,7 +8,7 @@ interface
uses
Classes, SysUtils, Math,
Graphics, Controls, LCLIntf, //LazLoggerBase,
Graphics, Controls, LCLIntf, // LazLoggerBase,
mvMapViewer, mvDrawingEngine, mvPluginCommon, mvGeoMath, mvTypes;
type
@ -147,7 +147,7 @@ var
incr: TIncrement;
incrementPx: Integer;
begin
Result := 1E6;
Result := 90;
fullRange := abs(Area.BottomRight.Lon - Area.TopLeft.Lon);
deg2px := fullRange / AMapView.ClientWidth;
@ -173,12 +173,20 @@ begin
Result := AMapView.Engine.ScreenRectToRealArea(Rect(0, 0, AMapView.ClientWidth, AMapView.ClientHeight));
if AMapView.Engine.CrossesDateline then
begin
if Result.BottomRight.Lon < Result.TopLeft.Lon then
if Result.BottomRight.Lon <= Result.TopLeft.Lon then
Result.BottomRight.Lon := Result.BottomRight.Lon + 360;
worldWidth := mvGeoMath.ZoomFactor(AMapView.Zoom) * TileSize.CX;
numWorlds := trunc(AMapView.ClientWidth / worldWidth);
Result.BottomRight.Lon := Result.BottomRight.Lon + numWorlds * 360;
end;
// Workaround for cyclic map at lowest zoom reaching across the date line:
// When its width is decreased slowly and the dateline is just crossed then
// there is only a small difference between left and right longitude numbers
// although the real difference is almost 180°.
// This causes a hang in the drawing routine. --> Add 360° to right longitude.
if (AMapView.Zoom < 2) and (Result.BottomRight.Lon - Result.TopLeft.Lon < 2) then
Result.BottomRight.Lon := Result.BottomRight.Lon + 360;
end;
procedure TMapGridPlugin.DrawGridLine(ADrawingEngine: TMvCustomDrawingEngine;