richview: fix bug where varied size fonts didn't start on baseline.

3 files changed, 16 insertions, 1 deletions

diff --git a/docview/components/richtext/CanvasFontManager.pas b/docview/components/richtext/CanvasFontManager.pas
index 71e6d2fa..fe9606e6 100644
--- a/docview/components/richtext/CanvasFontManager.pas
+++ b/docview/components/richtext/CanvasFontManager.pas
@@ -44,6 +44,7 @@ type
     constructor Create(ACanvas: TfpgCanvas; AWidget: TfpgWidget); reintroduce;
     destructor  Destroy; override;
     function    AverageCharWidth: longint;
+    function    CharAscender: longint;
     function    CharDescender: longint;
     function    CharHeight: longint;
     function    CharWidth( const C: TfpgChar ): longint;  // Retrieve the width of the given char, in the current font
@@ -314,6 +315,11 @@ begin
   Result := FCanvas.Font.TextWidth('c');
 end;
 
+function TCanvasFontManager.CharAscender: longint;
+begin
+  Result := FCanvas.Font.Ascent;
+end;
+
 function TCanvasFontManager.MaximumCharWidth: longint;
 begin
   Result := FCanvas.Font.TextWidth('W');
diff --git a/docview/components/richtext/RichTextDisplayUnit.pas b/docview/components/richtext/RichTextDisplayUnit.pas
index 613dba84..cfdd20a7 100644
--- a/docview/components/richtext/RichTextDisplayUnit.pas
+++ b/docview/components/richtext/RichTextDisplayUnit.pas
@@ -122,6 +122,7 @@ Procedure DrawRichTextLine( var FontManager: TCanvasFontManager;
     Line: TLayoutLine; Start: TPoint );
 var
   X, Y: longint;
+  YBaseLine: longint;
   Element: TTextElement;
   StartedDrawing: boolean;
   Style: TTextDrawStyle;
@@ -180,7 +181,7 @@ ProfileEvent('DEBUG:  DrawRichTextLine >>>');
 
   TextBlockStart := P;
 
-  Y := Start.Y; // + Line.MaxDescender; // co-ordinates are from top/left, so do we need descender? [Graeme]
+  YBaseLine := Start.Y + Line.MaxAscender;
 
   while P < EndP do
   begin
@@ -209,6 +210,7 @@ ProfileEvent('DEBUG:  DrawRichTextLine >>>');
           StartedDrawing := true;
         end;
 
+        Y := YBaseLine - FontManager.CharAscender;
         // Now do the drawing
         if Element.ElementType = teImage then
         begin
diff --git a/docview/components/richtext/RichTextLayoutUnit.pas b/docview/components/richtext/RichTextLayoutUnit.pas
index f5efe08a..8e39d65f 100644
--- a/docview/components/richtext/RichTextLayoutUnit.pas
+++ b/docview/components/richtext/RichTextLayoutUnit.pas
@@ -23,6 +23,7 @@ Type
     Length: longint;
     Height: longint;
     Width: longint;
+    MaxAscender: longint;
     MaxDescender: longint;
     MaxTextHeight: longint; // maximum height of text, doesn't include images
     LinkIndex: longint; // link index at start of line, if any
@@ -240,8 +241,10 @@ Procedure TRichTextLayout.CheckFontHeights( Var Line: TLayoutLine );
 var
   FontHeight: longint;
   Descender: longint;
+  Ascender: longint;
 begin
   FontHeight := FFontManager.CharHeight;
+  Ascender := FFontManager.CharAscender;
   Descender := FFontManager.CharDescender;
 
   if FontHeight > Line.Height then
@@ -252,6 +255,9 @@ begin
 
   if Descender > Line.MaxDescender then
     Line.MaxDescender := Descender;
+
+  if Ascender > Line.MaxAscender then
+    Line.MaxAscender := Ascender;
 end;
 
 function TRichTextLayout.IsValidBitmapIndex( Index: longint ): boolean;
@@ -297,6 +303,7 @@ Var
     CurrentLine := TLayoutLine.Create;
     CurrentLine.Style := Style;
     CurrentLine.Height := 0;
+    CurrentLine.MaxAscender := 0;
     CurrentLine.MaxDescender := 0;
     CurrentLine.MaxTextHeight := 0;
     CurrentLine.Width := 0;