bind buffer objects
[clinton/guile-figl.git] / TODO
1 # -*- org -*-
2
3 * Completeness
4
5 ** Complete the high-level GL binding.
6
7 *** Bind newer versions.
8
9 Would be nice to bind newer versions as well, while keeping the
10 compatibility profile.
11
12 The newer versions are backwards compatible with only rare exceptions
13 where some function's behaviour (but not prototype) is subtley
14 redefined. To support newer versions in a simple way we can export
15 all bindings and the user effectively chooses which version they use
16 by their choice of procedures.
17
18 Exporting particular profiles is a nice addition to this.
19
20 ** Complete the high-level GLU binding.
21
22 ** Complete the high-level GLX binding.
23
24 ** Complete the high-level GLUT binding.
25
26 *** Do not keep alive callback pointers indefinitely.
27
28 Perhaps by moving the gc-protect mechanism to the high-level bindings,
29 and track which callbacks are active on each window and globally.
30
31 Users of the low-level bindings can still use the foo-callback-*
32 helpers, but must assume control of pointer lifetime. Such an
33 approach permits great flexibility for alternative high-level
34 interfaces to reuse the low-level bindings.
35
36 ** Write an EGL binding.
37
38 There is a wip-egl branch with upstream documentation.
39
40 ** Packed structures.
41
42 To facilitate passing data to buffer objects. Rather than dealing
43 with bytevectors, offsets, and strides directly, we can use a
44 packed-struct. and field pair to compute the arguments for
45 vertex-pointer and friends (size, type, stride, and pointer).
46
47 Existing work:
48
49 - make-structure-descriptor (r7rs-large):
50 http://trac.sacrideo.us/wg/wiki/StructuresCowan
51
52 : (define-structure my-vertex-type
53 : (position 'f32 3 position-ref position-set!)
54 : (normal 'f32 3 normal-ref normal-set!)
55 : (color 'u8 4 color-ref color-set!)
56 : (non-gl-data 'f32 2))
57 : (define foo (list->structure my-vertex-type ...))
58 : ;; (set-vertex-pointer FIELD BV)
59 : (set-vertex-pointer position foo)
60 : (set-color-pointer color foo)
61 : ;; position, normal, etc. are identifiers bound to the required
62 : ;; field specs. by the define-structure expression.
63
64 - define-gl-array-format (cl-opengl):
65
66 Specifically maps each component to an OpenGL array type (one of
67 vertex, color, normal, ...). This permits automatically binding an
68 entire structure to the relevent array pointers.
69
70 Additional per-component options include:
71 - named access to sub-components (e.g. vertex x, y, z);
72 - whether values are normalized on assignment.
73
74 * Interface
75
76 ** Implement rest of spec parsing module.
77
78 To parse functions (gl.spec, etc.), enums, and typemaps.
79
80 ** Do not export meta-enumerations (version-2-1, etc.).
81
82 These are listed in the “Extensions” definition (enum.spec) and are
83 defined only to indicate the version or extension that introduces
84 various symbolic constants. In theory, all useful constants that
85 appear in version-2-1, for example, also appear in at least one other
86 enumeration which is an actual data type as referred to by gl.spec.
87
88 They can still be used to provide versioned interfaces and profiles,
89 there is just no need to export them as enumerations at run time.
90
91 Need to make sure all required symbolic constants will still be
92 accessible before removing these.
93
94 ** Make using enumerations implicit.
95
96 Instead of:
97
98 : (gl-begin (begin-mode triangles) ...)
99 : (gl-matrix-mode) => 123
100
101 more like this:
102
103 : (gl-begin #:triangles ...)
104 : (gl-matrix-mode) => #:modelview
105
106 and lists of symbols for bitfields.
107
108 Enumeration type checking (i.e. does gl-begin accept #:foo?) can be
109 done two ways.
110
111 *** Type checking by Guile.
112
113 Before this can be done we must parse gl.spec to know which enums to
114 apply for each procedure argument. _Probably_ foreign-types can no
115 longer be syntax either.
116
117 Requires also some manual overriding and mapping as there is some
118 inconsistency between gl.spec, gl.tm, and enum.spec. For example,
119 gl.spec occasionally refers to an enumeration type that is not listed
120 in enum.spec, or is listed under another name.
121
122 *** Type checking by GL.
123
124 Most GL procedures already check the range of enum and bitfield
125 arguments, and flag an invalid-enum error as appropriate. We can rely
126 on this and create a single, super-enumeration to convert to and from
127 symbols.
128
129 This may incur a notable performance hit due to the large number of
130 symbolic constants.
131
132 * Naming
133
134 ** Mangle low-level binding names.
135
136 Probably we should do this only if this low-level bindings are good
137 enough. In practice this means that output arguments should be natively
138 supported, and they low-level bindings should check errors as
139 appropriate.
140
141 ** TODO Document the naming convention.
142
143 Specifically we should document when a name changes significantly,
144 like when to use a "set-" prefix and the abbreviation expansions
145 ("accum" -> "accumulation-buffer", "coord" -> "coordinates").
146
147 Getting this done early will permit implementing the policy more
148 accurately.
149
150 ** Maybe drop the "gl-" prefix for high-level bindings.
151
152 The names for most gl, glu, etc. procedures are unique enough to not
153 conflict with each other, and most Scheme names generally. Removing
154 the prefix will make names where an additional prefix is used (such as
155 "set-") much more natural.
156
157 Users with specific namespace concerns can use selective and renaming
158 imports.
159
160 * Documentation
161
162 ** Figure out how to incorporate low-level bindings into the
163 documentation.
164
165 Often-times the high-level bindings just duplicate information from the
166 low-level bindings, but poorly. To do this, we'd have to make a map of
167 how to organize the low-level bindings, probably according to their
168 section in the specification.
169
170 ** Mangle enumeration names to link to the enumerator documentation.
171
172 ** Give an @anchor{} to each API element so that we can link back and
173 forth.
174
175 * Examples
176
177 ** examples/README explaining the layout.
178
179 ** OpenGL standards.
180
181 Language bindings typically provide ports of the standard examples, to
182 demonstrate usage patterns and their own unique style.
183
184 http://www.sgi.com/products/software/opengl/examples/index.html
185
186 Implement at least a few of these, their licencing is permissive
187 enough and they have been widely ported to Free Software language
188 bindings already.
189
190 ** More interesting demos.
191
192 * Meta
193
194 ** Mailing list?
195
196 ** Web page for documentation?
197
198 Both of these point towards hosting on savannah at some point. Figl
199 could become a GNU project but it will not have copyright assignment.