Ticket #398 (Fixed)Tue Dec 02 20:54:40 UTC 2014

SpriteExtend fails if plotting from a non-existant file

Details by Rick Murray (539):

A brief look at the source indicates that SpriteExtend, if called via JPEG_PlotFileScaled, should return an appropriate error if the file given does not exist.

This is not the case.

SYS “JPEG_PlotFileScaled”, “bogusfilename”, 0, 0, 0, 3

The result is:

Internal error: branch through zero

Additionally, this error percolates up to a task that calls this SWI (causing that to fail with the branch through zero reported by its error handler).

FIX :

File …mixed.RiscOS.Sources.Video.Render.SprExtend.Sources.SWIs

Line 596 (two below “jpegplotfilescaled_nofile”) says:

This does not match what was previously saved (in line 542).

Change to:

A standalone version of SpriteExtend built. The above SWI call now correctly returns the error:

File ‘bogusfilename’ not found

I’ve just had a look, it seems as if the other SWIs (JPEG_PlotFileTransformed and JPEG_FileInfo) are okay and correctly report nonexistent files.