Changeset 487 for trunk/Packages/DpiControls/NativePixelPointer.pas

Timestamp:

Dec 8, 2023, 11:39:45 PM (5 months ago)

Author:

chronos

Message:

• Added: Range checking for TPixelPointer record type.

File:

• trunk/Packages/DpiControls/NativePixelPointer.pas (modified) (4 diffs)

trunk/Packages/DpiControls/NativePixelPointer.pas

@@ -32 +32 @@
     BytesPerPixel: Integer;
     BytesPerLine: Integer;
+    Data: PPixel32;
+    Width: Integer;
+    Height: Integer;
     procedure NextLine; inline; // Move pointer to start of next line
     procedure PreviousLine; inline; // Move pointer to start of previous line
@@ -38 +41 @@
     procedure SetXY(X, Y: Integer); inline; // Set pixel position relative to base
     procedure SetX(X: Integer); inline; // Set horizontal pixel position relative to base
+    procedure CheckRange; inline; // Check if current pixel position is not out of range
+    class function Create(Bitmap: TRasterImage; BaseX: Integer = 0; BaseY: Integer = 0): TPixelPointer; static;
   end;
   PPixelPointer = ^TPixelPointer;
 
-  function PixelPointer(Bitmap: TRasterImage; BaseX: Integer = 0; BaseY: Integer = 0): TPixelPointer; inline;
   function Color32ToColor(Color: TColor32): TColor;
   function ColorToColor32(Color: TColor): TColor32;
@@ -48 +52 @@
 implementation
 
-{ TPixel32 }
+resourcestring
+  SOutOfRange = 'Pixel pointer out of range';
+  SWrongBitmapSize = 'Wrong bitmap size [width: %d, height: %d]';
+
+  { TPixel32 }
 
 procedure TPixel32.SetRGB(Color: TColor32);
@@ -97 +105 @@
 end;
 
-function PixelPointer(Bitmap: TRasterImage; BaseX: Integer;
+procedure TPixelPointer.CheckRange;
+begin
+  {$IFOPT R+}
+  if (PByte(Pixel) < PByte(Data)) or
+    (PByte(Pixel) >= PByte(Data) + (Width + Height * BytesPerLine) * BytesPerPixel) then
+    raise Exception.Create(SOutOfRange);
+  {$ENDIF}
+end;
+
+class function TPixelPointer.Create(Bitmap: TRasterImage; BaseX: Integer;
   BaseY: Integer): TPixelPointer;
 begin
+  Result.Width := Bitmap.Width;
+  Result.Height := Bitmap.Height;
+  if (Result.Width < 0) or (Result.Height < 0) then
+    raise Exception.Create(Format(SWrongBitmapSize, [Result.Width, Result.Height]));
   Result.BytesPerLine := Bitmap.RawImage.Description.BytesPerLine;
   Result.BytesPerPixel := Bitmap.RawImage.Description.BitsPerPixel shr 3;
+  Result.Data := PPixel32(Bitmap.RawImage.Data);
   Result.Base := PPixel32(Bitmap.RawImage.Data + BaseX * Result.BytesPerPixel +
     BaseY * Result.BytesPerLine);