Changeset 487 for trunk/Packages/DpiControls/Dpi.PixelPointer.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/Dpi.PixelPointer.pas (modified) (10 diffs)

trunk/Packages/DpiControls/Dpi.PixelPointer.pas

@@ -4 +4 @@
 
 uses
-  Classes, SysUtils, Dpi.Graphics;
+  Classes, SysUtils, Dpi.Graphics, Dpi.Common;
 
 type
@@ -35 +35 @@
     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
@@ -41 +44 @@
     procedure SetXY(X, Y: Integer); inline; // Set pixel position relative to base
     procedure SetX(X: Integer); inline; // Set horizontal pixel position relative to base
-    class function Create(Bitmap: TRasterImage; BaseX: Integer = 0; BaseY: Integer = 0): TPixelPointer; inline; static;
+    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;
@@ -63 +67 @@
 implementation
 
+resourcestring
+  SOutOfRange = 'Pixel pointer out of range';
+  SWrongBitmapSize = 'Wrong bitmap size [width: %d, height: %d]';
+
 { TPixel32 }
 
@@ -83 +91 @@
   Line := Pointer(Line) + BytesPerLine;
   Pixel := Line;
+  CheckRange;
 end;
 
@@ -89 +98 @@
   Line := Pointer(Line) - BytesPerLine;
   Pixel := Line;
+  CheckRange;
 end;
 
@@ -94 +104 @@
 begin
   Pixel := Pointer(Pixel) + BytesPerPixel;
+  CheckRange;
 end;
 
@@ -99 +110 @@
 begin
   Pixel := Pointer(Pixel) - BytesPerPixel;
+  CheckRange;
 end;
 
@@ -110 +122 @@
 begin
   Pixel := Pointer(Line) + X * BytesPerPixel;
+  CheckRange;
+end;
+
+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;
 
@@ -298 +320 @@
   BaseY: Integer): TPixelPointer;
 begin
+  Result.Width := ScaleToNative(Bitmap.Width);
+  Result.Height := ScaleToNative(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);