create_similar_image_surface

Description:

[ Version ( since = "3.10" ) ]
public ImageSurface create_similar_image_surface (Format format, int width, int height, int scale)

Create a new image surface that is efficient to draw on the given this.

Initially the surface contents are all 0 (transparent if contents have transparency, black otherwise.)

The width and height of the new surface are not affected by the scaling factor of the this , or by the scale argument; they are the size of the surface in device pixels. If you wish to create an image surface capable of holding the contents of this you can use:

  int scale = gdk_window_get_scale_factor (window);
  int width = gdk_window_get_width (window) * scale;
  int height = gdk_window_get_height (window) * scale;

  // format is set elsewhere
  cairo_surface_t *surface =
    gdk_window_create_similar_image_surface (window,
                                             format,
                                             width, height,
                                             scale);

Note that unlike Surface.similar_image, the new surface's device scale is set to scale, or to the scale factor of this if scale is 0.

Parameters:

this	window to make new surface similar to, or null if none
format	the format for the new surface
width	width of the new surface
height	height of the new surface
scale	the scale of the new surface, or 0 to use same as this

Returns:

a pointer to the newly allocated surface. The caller owns the surface and should call cairo_surface_destroy when done with it.

This function always returns a valid pointer, but it will return a pointer to a “nil” surface if other is already in an error state or any other error occurs.