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PremultiplyAlpha

Premultiply the alpha on a block of pixels.

This is safe to use with ASrc = ADst, but not for other overlapping areas.

Definition

Unit: Neslib.Sdl3.Video

procedure PremultiplyAlpha(const AWidth, AHeight: Integer; 
  const ASrcFormat: TSdlPixelFormat; const ASrc: Pointer; 
  const ASrcPitch: Integer; const ADstFormat: TSdlPixelFormat; 
  const ADst: Pointer; const ADstPitch: Integer; const ALinear: Boolean); inline

Parameters

AWidth: Integer : The width of the block to convert, in pixels.

AHeight: Integer : The height of the block to convert, in pixels.

ASrcFormat: TSdlPixelFormat : The pixel format of ASrc.

ASrc: Pointer : A pointer to the source pixels.

ASrcPitch: Integer : The pitch of the source pixels, in bytes.

ADstFormat: TSdlPixelFormat : The pixel format of ADst.

ADst: Pointer : A pointer to be filled in with premultiplied pixel data.

ADstPitch: Integer : The pitch of the destination pixels, in bytes.

ALinear: Boolean : True to convert from sRGB to linear space for the alpha multiplication, False to do multiplication in sRGB space.

Exceptions

ESdlError: Raised on failure.

See Also