Sizer 4.0 Detailed Info

This page contains a bit about the implementation details of Sizer 4.0. It is intended for those who want to know a bit more about what goes on under the hood.

Increased stability

Sizer 4.0 works slightly differently from previous versions of the program. Sizer installs hooks into all running applications and uses them to detect when a window is resized or when a user interacts with the border. In previous versions of Sizer, special handling was performed inside the target application itself (rather than in the Sizer executable). This approach is both efficient and highly flexible. The problem is that hook code is at the mercy of the target application. Incompatibilities occur when the target application uses undocumented Windows API or does not follow standard Windows programming guidelines (which is far more common than one might think). Therefore, Sizer 4.0 follows a slightly different approach. The hook portion only ever listens and then forwards important events to the main Sizer executable. Sizer 4.0 severely restricts the processing it performs in the target application and hence minimizes the risk of incompatibilities. The downside is that Sizer no longer is able to do things that were possible in previous versions. This includes:

• System menu integration. Sizer 4.0 no longer attempts to add entries to the system menu. This didn’t always work in previous versions of Sizer anyway because target applications would create a popup menu that looks like the system menu rather than using the system provided one.
• Snap to grid resizing. Snapping requires interfering with the target application. Sizer 4.0 no longer does this because of the risk of introducing incompatibilities.

Compensate for Frame Effects

What does Compensate for Desktop Window Manager frame effects mean?

This setting determines how Sizer calculates a window’s dimensions. There are two primary methods:

• Standard Method (GetWindowRect): This returns the size and position of the window as defined by the system. On versions of Windows older than Windows 10, this matched exactly what the user saw on screen.
• DWM-Aware Method: Since Windows Vista, the Desktop Window Manager (DWM) added effects like shadows and transparency. On Windows 10, the window border style changed, adding a small area (typically 7 pixels) around the window for these effects. Consequently, the standard API call now returns a rectangle slightly larger than the visible window area.

How this option works:

• Enabled (Default): Sizer ignores those extra pixels and uses only the visible area of the window.
• Disabled : Sizer uses the actual window rectangle (including the extra border pixels).

Important Notes:

• This option has no effect on Windows 8.1 or earlier.
• If enabled on Windows 10, external tools (like Spy++) may report dimensions larger than what you see in Sizer.
• If enabled on Windows 10, a screen grab (Alt+PrintScreen) will capture a bitmap that matches the exact dimensions configured in Sizer.