Adds PNG loading support.

The unit uses the fcl-image backend to load the image. This is slightly
slower than the native implementations for BMP and JPG. But at least now
we have PNG support too.

5 files changed, 144 insertions, 6 deletions

diff --git a/src/corelib/fpg_imgfmt_png.pas b/src/corelib/fpg_imgfmt_png.pas
new file mode 100644
index 00000000..e4a46a7d
--- /dev/null
+++ b/src/corelib/fpg_imgfmt_png.pas
@@ -0,0 +1,130 @@
+{
+    fpGUI  -  Free Pascal GUI Toolkit
+
+    Copyright (C) 2006 - 2012 See the file AUTHORS.txt, included in this
+    distribution, for details of the copyright.
+
+    See the file COPYING.modifiedLGPL, included in this distribution,
+    for details about redistributing fpGUI.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+    Description:
+      PNG image loading using the Free Pascal library: fcl-image
+}
+
+unit fpg_imgfmt_png;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  SysUtils,
+  Classes,
+  fpg_base,
+  fpg_main,
+  FPImage,
+  FPReadPNG;
+
+function LoadImage_PNG(const AFileName: TfpgString): TfpgImage;
+function LoadImage_PNGcrop(const AMaxWidth, AMaxHeight: integer; const AFileName: TfpgString): TfpgImage;
+
+
+implementation
+
+uses
+  fpg_utils;
+
+function LoadImage_PNG(const AFileName: TfpgString): TfpgImage;
+var
+  i, j: integer;
+  colorA: TFPColor;   // struct Red, Green, Blue, Alpha: word
+  colorB: TfpgColor;  // ONE long 32-bit-word
+  imga: TFPCustomImage;
+  imgb: TfpgImage;
+  xlocal, ylocal: integer;
+begin
+  Result := nil;
+  if not fpgFileExists(AFileName) then
+    Exit; //==>
+
+  imga := TFPMemoryImage.Create(0, 0);
+  try
+    imga.LoadFromFile(AFileName, TFPReaderPNG.Create); // auto size image
+  except
+    imga := nil;
+    imgb := nil;
+  end;
+  if imga <> nil then
+  begin
+    xlocal := imga.Width;
+    ylocal := imga.Height;
+    imgb   := TfpgImage.Create;
+    imgb.AllocateImage(32, xlocal, ylocal); // 32=colordepth
+    for i := 0 to ylocal - 1 do
+      for j := 0 to xlocal - 1 do
+      begin
+        colorA := imga.Colors[j, i];
+        colorB := (colorA.Blue shr 8) or (colorA.Green and $FF00) or ((colorA.Red and $FF00) shl 8);
+        imgb.Colors[j, i] := colorB;
+      end;
+    imgb.UpdateImage;
+  end;
+  imga.Free;
+  Result := imgb;
+end;
+
+function LoadImage_PNGcrop(const AMaxWidth, AMaxHeight: integer; const AFileName: TfpgString): TfpgImage;
+var
+  i, j: integer;
+  colorA: TFPColor;   // struct Red, Green, Blue, Alpha: word
+  colorB: TfpgColor;  // ONE long 32-bit-word
+  imga: TFPCustomImage;
+  imgb: TfpgImage;
+  xlocal, ylocal: integer;
+begin
+  Result := nil;
+  if not fpgFileExists(AFileName) then
+    Exit; //==>
+
+          // Maximum image size of AMaxWidth by AMaxHeight.
+          // Actual image imga.Width (AMaxWidth) and imga.Height (AMaxHeight).
+          // Calculated to fit the image within required size: xlocal, ylocal
+  imga := TFPMemoryImage.Create(0, 0);
+  try
+    imga.LoadFromFile(AFileName, TFPReaderPNG.Create); // auto size image
+  except
+    imga := nil;
+    imgb := nil;
+  end;
+  if imga <> nil then
+  begin
+    if imga.Width > AMaxWidth then
+      xlocal := AMaxWidth
+    else
+      xlocal := imga.Width;
+    if imga.Height > AMaxHeight then
+      ylocal := AMaxHeight
+    else
+      ylocal := imga.Height;
+    imgb := TfpgImage.Create;
+    imgb.AllocateImage(32, xlocal, ylocal); // 32=colordepth
+    for i := 0 to ylocal - 1 do
+      for j := 0 to xlocal - 1 do
+      begin
+        colorA := imga.Colors[j, i];
+        colorB := (colorA.Blue shr 8) or (colorA.Green and $FF00) or ((colorA.Red and $FF00) shl 8);
+        imgb.Colors[j, i] := colorB;
+      end;
+    imgb.UpdateImage;
+  end;
+  imga.Free;
+  Result := imgb;
+end;
+
+
+end.
+
diff --git a/src/corelib/gdi/fpgui_toolkit.lpk b/src/corelib/gdi/fpgui_toolkit.lpk
index 946d234a..d6a28998 100644
--- a/src/corelib/gdi/fpgui_toolkit.lpk
+++ b/src/corelib/gdi/fpgui_toolkit.lpk
@@ -31,7 +31,7 @@
     <Description Value="fpGUI Toolkit"/>

     <License Value="LGPL 2 with static linking exception."/>

     <Version Minor="8" Build="0"/>

-    <Files Count="88">

+    <Files Count="89">

       <Item1>

         <Filename Value="..\stdimages.inc"/>

         <Type Value="Include"/>

@@ -384,6 +384,10 @@
         <Filename Value="..\..\gui\fpg_readonly.pas"/>

         <UnitName Value="fpg_readonly"/>

       </Item88>

+      <Item89>

+        <Filename Value="..\fpg_imgfmt_png.pas"/>

+        <UnitName Value="fpg_imgfmt_png"/>

+      </Item89>

     </Files>

     <LazDoc Paths="..\..\..\docs\xml\corelib;..\..\..\docs\xml\corelib\x11;..\..\..\docs\xml\corelib\gdi;..\..\..\docs\xml\gui"/>

     <RequiredPkgs Count="1">

@@ -400,4 +404,4 @@
       <IgnoreBinaries Value="False"/>

     </PublishOptions>

   </Package>

-</CONFIG>

+</CONFIG>
\ No newline at end of file
diff --git a/src/corelib/gdi/fpgui_toolkit.pas b/src/corelib/gdi/fpgui_toolkit.pas
index 7ec7e35c..1fef2442 100644
--- a/src/corelib/gdi/fpgui_toolkit.pas
+++ b/src/corelib/gdi/fpgui_toolkit.pas
@@ -20,8 +20,8 @@ uses
   fpg_extgraphics, fpg_ColorMapping, fpg_ColorWheel, fpg_interface, 

   fpg_editbtn, fpg_imgfmt_jpg, fpg_imgutils, fpg_OLEDragDrop, 

   fpg_stylemanager, fpg_style_win2k, fpg_style_motif, fpg_style_clearlooks, 

-  fpg_style_bluecurve, fpg_style_bitmap, fpg_readonly;

+  fpg_style_bluecurve, fpg_style_bitmap, fpg_readonly, fpg_imgfmt_png;

 

 implementation

 

-end.

+end.
\ No newline at end of file
diff --git a/src/corelib/x11/fpgui_toolkit.lpk b/src/corelib/x11/fpgui_toolkit.lpk
index 7a18d789..46614518 100644
--- a/src/corelib/x11/fpgui_toolkit.lpk
+++ b/src/corelib/x11/fpgui_toolkit.lpk
@@ -31,7 +31,7 @@
     <License Value="LGPL 2 with static linking exception.
 "/>
     <Version Minor="8"/>
-    <Files Count="91">
+    <Files Count="92">
       <Item1>
         <Filename Value="../stdimages.inc"/>
         <Type Value="Include"/>
@@ -396,6 +396,10 @@
         <Filename Value="../../gui/fpg_readonly.pas"/>
         <UnitName Value="fpg_readonly"/>
       </Item91>
+      <Item92>
+        <Filename Value="../fpg_imgfmt_png.pas"/>
+        <UnitName Value="fpg_imgfmt_png"/>
+      </Item92>
     </Files>
     <LazDoc Paths="../../../docs/xml/corelib/;../../../docs/xml/corelib/x11/;../../../docs/xml/corelib/gdi/;../../../docs/xml/gui/"/>
     <RequiredPkgs Count="1">
diff --git a/src/corelib/x11/fpgui_toolkit.pas b/src/corelib/x11/fpgui_toolkit.pas
index 8c66a9a3..b2a4b774 100644
--- a/src/corelib/x11/fpgui_toolkit.pas
+++ b/src/corelib/x11/fpgui_toolkit.pas
@@ -19,7 +19,7 @@ uses
   fpg_hint, fpg_spinedit, fpg_extgraphics, fpg_ColorMapping, fpg_ColorWheel, 
   fpg_interface, fpg_editbtn, fpg_imgfmt_jpg, fpg_imgutils, fpg_stylemanager, 
   fpg_style_win2k, fpg_style_motif, fpg_style_clearlooks, fpg_style_bluecurve, 
-  fpg_style_bitmap, fpg_readonly;
+  fpg_style_bitmap, fpg_readonly, fpg_imgfmt_png;
 
 implementation