add bindings for begin/end and vertex specification

* figl/gl.scm: Initial work on high-level bindings for begin/end and
  vertex specification.  Choosing to only export unpacked float
  variants at this time.  Refer to inline comments for details.

diff --git a/figl/gl.scm b/figl/gl.scm
index 94b5048..5767195 100644 (file)
--- a/figl/gl.scm
+++ b/figl/gl.scm
@@ -1,5 +1,6 @@
 ;;; figl
 ;;; Copyright (C) 2013 Andy Wingo <wingo@pobox.com>
+;;; Copyright (C) 2013 Daniel Hartwig <mandyke@gmail.com>
 ;;; 
 ;;; Figl is free software: you can redistribute it and/or modify it
 ;;; under the terms of the GNU Lesser General Public License as
@@ -23,5 +24,88 @@
 
 (define-module (figl gl)
   #:use-module (figl runtime)
-  #:use-module (figl gl low-level))
+  #:use-module (figl gl enums)
+  #:use-module ((figl gl low-level) #:renamer (symbol-prefix-proc '%)))
 
+;; Notice there is no #:export clause.  Exports are done inline to
+;; facilitate re-exporting low-level bindings (and changing that
+;; choice), and identifying gaps in the API.
+;;
+;; There are two sets of exports for each section.  The first is for
+;; bindings defined in the specification, exported in order.  The
+;; second is for additional procedures not defined by the spec. but
+;; relevant to the section, for example with-gl-begin.
+;;
+;; At least keep this format until the bindings are fairly complete.
+
+(module-use! (module-public-interface (current-module))
+             (resolve-interface '(figl gl enums)))
+
+;;;
+;;; 2.6 Begin/End Paradigm
+;;;
+
+(define (gl-edge-flag flag)
+  (%glEdgeFlag (if flag (boolean true) (boolean false))))
+
+(re-export (%glBegin gl-begin)
+           (%glEnd gl-end))
+
+(export gl-edge-flag)
+
+(define-syntax with-gl-begin ; terrible name
+  (syntax-rules ()
+    ((_ mode body ...)
+     (begin
+       (%glBegin mode)
+       body ...
+       (%glEnd)))))
+
+(export-syntax with-gl-begin)
+
+;;;
+;;; 2.7 Vertex Specification
+;;;
+
+;; Note that these are float variants only.  This has implications for
+;; some functions whose integer variants normalize their arguments.
+;; The corresponding float variants expect normalized input, usually
+;; in the range [0, 1].  Refer to the OpenGL specification for
+;; details.
+;;
+;; For access to non-float variants please use the appropriate
+;; low-level binding.
+
+;; TODO: Maybe re-export packaged variants here.  Unpacked byte
+;; variants?
+
+(define* (gl-vertex x y #:optional (z 0.0) (w 1.0))
+  (%glVertex4f x y z w))
+
+(define* (gl-tex-coord s #:optional (t 0.0) (r 0.0) (q 1.0))
+  (%glTexCoord4f s t r q))
+
+(define* (gl-multi-tex-coord texture s #:optional (t 0.0) (r 0.0) (q 1.0))
+  (%glMultiTexCoord4f texture s t r q))
+
+(define* (gl-color red green blue #:optional (alpha 1.0))
+  (%glColor4f red green blue alpha))
+
+(define* (gl-vertex-attrib index x #:optional (y 0.0) (z 0.0) (w 1.0))
+  (%glVertexAttrib4f index x y z w))
+
+(export gl-vertex
+        gl-tex-coord
+        gl-multi-tex-coord
+        gl-color)
+
+(re-export (%glNormal3f gl-normal)
+           (%glFogCoordf gl-fog-coord)
+           (%glSecondaryColor3f gl-secondary-color)
+           (%glIndexi gl-index))
+
+;;;
+;;; 2.10 Rectangles
+;;;
+
+(re-export (%glRectf gl-rectangle))