[Image-SIG] more on ImageFont.

Anthony Baxter arb@connect.com.au
Sat, 11 Jul 1998 14:07:26 +1000

Ok, as of 0.3b1, I canna get ImageFont to do anything but error. I've tried
regenerating the .pil font files, and I've even dug into the C source code

File "test", line 10, in text
File "/opt/python/lib/python1.5.1/site/ImageFont.py", line 87, in getmask
SystemError: NULL result without error in call_object

Breaking this down into 
            tmp2 = tuple(m[6:10])  # tmp2 = (55, 0, 59, 7)
            tmp = self.image.im.crop(tmp2)                 
            im.im.paste(tmp, (x0+x, y0, x1+x, y1))
shows the error occurs on the "crop()" line.

The problem appears to be in libImaging/Crop.c, in the ImagingCrop function.
This section of code was added between 0.2b3 and 0.3something. I'm stuffed
if I can figure out what it's meant to do, or how it's meant to work properly.

ifdef'ing this section out at least makes the getmask() calls seem to work.

Anyone know what it's meant to do?

    /* Determine which region to copy */
    xoff = yoff = 0;
    if (x0 < 0)
        xsize += x0, xoff = -x0, x0 = 0;
    if (x0 + xsize > imOut->xsize)
        xsize = imOut->xsize - x0;
    if (y0 < 0)
        ysize += y0, yoff = -y0, y0 = 0;
    if (y0 + ysize > imOut->ysize)
        ysize = imOut->ysize - y0;    

    if (xsize <= 0 || ysize <= 0)     
        return 0;