Exception: Surface does not respond to 'getData'

[galexite]

When using the following code to resize an image so that I can use it in my program, I get the following error:

resizing main.png from 640x640 to 20x20

  Exception: Surface does not respond to 'getData'
  ---------
  Surface getData                      Image.io 26
  Image resizedTo                      art.io 2
  CLI doFile                           Z_CLI.io 140
  CLI run                              IoState_runCLI() 1

My code is:

i := Image open("main.png") resizedTo(20, 20)

[ghost]

Might need a bit of help on this one...

Tracing backwards from George's error:

• Image.io:26: outputSurface getData fails (does not respond to message)
• Image.io:22: outputSurface is created by CairoImageSurface create
• IoCairoImageSurface.c:84: creates a surface with IoCairoSurface_newWithRawSurface_, passing in a raw surface from cairo_image_surface_create
• IoCairoSurface.c:78: IoCairoSurface_newWithRawSurface_ looks at the type of surface and sets variable initFunc to an appropriate function (e.g. IoCairoImageSurface_proto), presumably to create an appropriate subclass of the Cairo surface. However initFunc is not then used.

The result is (I think) that the return value of CairoImageSurface create is a CairoSurface but not a CairoImageSurface - and the former does not have a getData method.

Possibly in IoCairoSurface.c:96 the new surface should be created by calling initFunc rather than IOCLONE(IoState_protoWithId_(state, protoId))

I'm not sure.

[ghost]

OK, I've got this diff bypassing IoCairoSurface_newWithRawSurface_, which I think is bust.

diff --git a/addons/Cairo/source/IoCairoImageSurface.c b/addons/Cairo/source/IoCairoImageSurface.c
index 5f16b8f..96f8b69 100644
--- a/addons/Cairo/source/IoCairoImageSurface.c
+++ b/addons/Cairo/source/IoCairoImageSurface.c
@@ -81,7 +81,10 @@ IoObject *IoCairoImageSurface_create(IoCairoImageSurface *self, IoObject *locals
        cairo_format_t format = (cairo_format_t)IoMessage_locals_intArgAt_(m, locals, 0);
        int w = IoMessage_locals_intArgAt_(m, locals, 1);
        int h = IoMessage_locals_intArgAt_(m, locals, 2);
-       return IoCairoSurface_newWithRawSurface_(IOSTATE, m, cairo_image_surface_create(format, w, h));
+       cairo_surface_t* surface = cairo_image_surface_create(format, w, h);
+       IoCairoImageSurface* created = IoObject_rawClonePrimitive(self);
+       IoObject_setDataPointer_(created, surface);
+       return created;
 }

 IoObject *IoCairoImageSurface_createForData(IoCairoImageSurface *self, IoObject *locals, IoMessage *m)

Q. is this the right way to create a clone of an ImageSurface?
With this code, George's code does work as it should, but:

1. Doesn't fix the underlying issue with IoCairoSurface_newWithRawSurface_
2. I also uncovered a bug in Image open() - it doesn't work with paletted PNG files.
   Onwards and upwards!