* Clean up the API in preparation for freezing and release.

* Implement a PDF backend.

* Make a more interesting PS backend, (other than the current
"giant-image for every page" approach).

* Figure out what to do with DPI for image/png backends.

* Change stroke code to go through one giant polygon. This will fix
problems with stroking self-intersecting paths.

* Implement cairo_stroke_path, (very easy to do after the above change
is done).

* Fix the intersection problem, (see reference to Hobby's paper
mentioned in cairo_traps.c).

* Add a new cairo_text_glyphs function (a sort of bridge between the
toy and the real text API):

	>       void
	>       cairo_text_glyphs (cairo_t *cr, const unsigned char *utf8,
	>                          cairo_glyph_t *glyphs, int *num_glyphs);
	>
	> with num_glyphs as an input-output parameter. The behavior of this
	> function would be such that calling:
	>
	>       cairo_text_glyphs (cr, string, glyphs, &num_glyphs);
	>       cairo_show_glyphs (cr, glyphs, num_glyphs);
	>
	> would be equivalent too:
	>
	>       cairo_show_text (cr, string);
	>
	> as long as the original size of glyphs/num_glyphs was large
	> enough.

* Implement dashing for cairo_curve_to.

* Implement support for programmatic patterns, (ie. figure out how to
do gradients the Right Way).

* Implement cairo_arc_to.

* Fix support for old X servers so that it is not swamped with image
transport. The key idea is to assume that nothing external to cairo
will be drawing to the same drawable after it is handed to
cairo. Beyond that, we might actually provide support for cooperating
with external entities by adding one or more of the following
functions:

   cairo_flush
   cairo_erase
   cairo_mark_dirty

* Re-implement the trapezoid rasterization algorithm according to the
new "specification".

* Stroking degenerate paths should still draw caps.  Round caps are
easy; square should probably draw an axis aligned square.

* Verification, profiling, optimization.

A comparison with PostScript
============================

Here's a list of several classes of PostScript operators indicating
which operators have rough equivalents in cairo and which do not. In
general, the name of a cairo function corresponding to a PostScript
operator can be obtained by inserting a '_' between each word and
prefixing it with "cairo_". For example, "cairo_move_to" corresponds
to the PostScript "moveto".

In cases where the name of the cairo function deviates from this
convention, or when the behavior of the cairo function is
significantly different, the change is noted in parentheses below.

This list is not exhaustive, (there are definitely some minor (major?)
semantic deviations that are not noted below). Also, this list is
almost certainly out of date with respect to the current cairo
implementation. Caveat lector.

Operators that are not yet in cairo, but probably should be: arcto,
strokepath, rectclip?, clipsave/restore?, setstrokeadjust?,
currentdash, grestoreall?, initgraphics?, currentgstate?, setgstate?,
erasepage?, setsmoothness?

Painting operators
------------------
in cairo: stroke, fill, eofill (set_fill_rule/fill), image
(show_surface)

not in cairo: erasepage, rectstroke, rectfill, shfill, colorimage,
imagemask

Path construction operators
---------------------------
in cairo: arc, arcn (arc_negative), newpath, moveto, rmoveto
(rel_move_to), lineto, rlineto (rel_line_to), curveto, rcurveto
(rel_curve_to), closepath, currentpoint, charpath (text_path),
pathforall (current_path), flattenpath (current_path_flat)

not in cairo: arct, arcto, reversepath, strokepath, clippath, pathbbox

Clipping
--------
in cairo:  clip, eoclip (set_fill_rule/clip)

not in cairo: initclip, rectclip, clipsave, cliprestore

Graphics state operators
------------------------
in cairo: setlinewidth, currentlinewidth, setlinecap, currentlinecap,
setlinejoin, currentlinejoin, setmiterlimit, currentmiterlimit,
setdash

not in cairo: setstrokeadjust, currentstrokeadjust, currentdash

Color specification operators
-----------------------------
in cairo:  setrgbcolor, currentcolor

not in cairo: setcolor, setgray, currentgray, currentrgbcolor,
sethsbcolor, currenthsbcolor, setcmykcolor, currentcmykcolor,
setcolorspace, currentcolorspace

Form and pattern operators
--------------------------
in cairo: setpattern, makepattern (lock_pattern)

not in cairo: execform

Whole-state manipulation
------------------------
in cairo:  gsave (save), grestore (restore)

not in cairo: grestoreall, initgraphics, gstate, currentgstate,
setgstate

Coordinate system and matrix operators
--------------------------------------
in cairo: identmatrix (identity_matrix), initmatrix (default_matrix),
setmatrix, translate, scale, rotate, concatmatrix, currentmatrix,
transform (transform_point), dtransform (transform_distance)

not in cairo: matrix, defaultmatrix, concat, itransform, idtransform,
invertmatrix

Insideness testing
------------------
in cairo: infill, instroke, ineofill (set_fill_rule/in_fill)

not in cairo: inufill, inustroke, inueofill

Device setup
------------
in cairo: showpage, copypage

not in cairo: setpagedevice, currentpagedevice, nulldevice

Glyph and font operators
------------------------
in cairo: currentfont, definefont (font_create_for_ft_face),
undefine_font (font_destroy), findfont (font_create), makefont
(transform_font), setfont, scalefont, selectfont, show (show_text),
stringwidth (x/y in text_extents), xyshow (glyph_show -- but ignoring
current_point and using absolute positions)

not in cairo, (and likely not needed): composefont, rootfont, ashow,
widthshow, awidthshow, xshow, xyshow, yshow, glyphshow, cshow, kshow,
FontDirectory, GlobalFontDirectory, StandardEncoding,
ISOLatin1Encoding, findencoding, setcachedevice, setcachedevice2,
setcharwidth

Graphics state operators (device-dependent)
-------------------------------------------
in cairo:  setflat (set_tolerance), currentflat (current_tolerance)

not in cairo: sethalftone, currenthalftone, setscreen, currentscreen,
setcolorscreen, currentcolorscreen, settransfer, currenttransfer,
setcolortransfer, currentcolortransfer, setblackgeneration,
currentblackgeneration, setundercolorremoval,
currentundercolorremoval, setcolorrendering, currentcolorrendering,
setoverprint, currentoverprint, setsmoothness, currentsmoothness

PostScript operators never to be in cairo
-----------------------------------------
Operator Stack Manipulation Operators, Arithmetic and Math Operators,
Array Operators, Packed Array Operators, Dictionary Operators, String
Operators, Rational,Boolean,and Bitwise Operators, Control Operators,
Type,Attribute,and Conversion Operators, File Operators, Resource
Operators, Virtual Memory Operators, Miscellaneous Operators,
Interpreter Parameter Operators, Errors, User Path Operators