[Overview][Constants][Types][Classes][Procedures and functions][Index] | Reference for unit 'IntfGraphics' (#lcl)

# TLazReaderBMP.InternalReadHead

Performs actions needed to read the header for the bitmap and return the width and height as a TPoint value.

## Declaration

Source position: intfgraphics.pas line 534

`protected procedure TLazReaderBMP.InternalReadHead; override;`

## Description

InternalReadHead is an overridden TPoint class function. The return value contains the width and height for the bitmap read from the header. The X member contains the width for the bitmap. The Y member contains the height for the bitmap. The return value is an empty TPoint instance (X=0, Y=0) if the bitmap file header does not contain the bitmap magic word "BM" in the header type.

InternalReadHead is conditionally defined for FPC compiler versions prior to 3.3.1 where the InternalSize function was not implemented in an ancestor class to use values in the bitmap header.

## Version info

Added in LCL version 4.0. It is conditionally defined for FPC compiler versions prior to 3.3.1 only.