`pdfSetMatrix`

Apply an arbitrary transform to the current coordinate system.

BOOL32 __stdcall pdfSetMatrix(PPDF IPDF, TCTM* Matrix);

Delphi

function pdfSetMatrix(const IPDF: PPDF; var Matrix: TCTM): LongBool; stdcall;

Purpose. Apply an arbitrary transform to the current coordinate system.

Description. Despite its "Set" name suggesting it replaces the CTM outright, this function concatenates Matrix onto whatever transformation is already active — internally it calls the exact same ConcatMatrix used to implement the PDF cm operator, which both writes the cm operator and updates FCTM via ComposeCTM. To achieve a true "replace the CTM from scratch" effect, a caller must first read the inverse of the current matrix (via pdfGetMatrix and manual inversion — no inverse helper is exposed in this ABI) and concatenate that before applying the desired absolute matrix.

Parameters.

Parameter	Description
`IPDF`	Document handle.
`Matrix`	The `[a b c d x y]` matrix to concatenate onto the current transform.

Return value. True on success; False if there is no current content stream (works for an open template, not just an open page — contrast with pdfGetMatrix's stricter open-page requirement).

Remarks. Functionally, pdfSetMatrix(M) is exactly equivalent to writing the cm operator with M's six values directly — there is no "set absolute" primitive in this ABI.

See also. pdfGetMatrix, pdfMultiplyMatrix.

C# (P/Invoke)

wrappers/dotnet/LumasPdf.cs

[return: MarshalAs(UnmanagedType.Bool)]

Area

Graphics