render: Reimplement rendering engine using functional combinators.

Warning: This is a huge commit.

I completely gutted the old scene graph and replaced it with a somewhat
monadic rendering combinator module instead.  The interface remains
purely functional, but replaces the <model> data type with procedures in
the rendering monad instead.  This opens the door for
rendering *anything*, not just meshes.  Now I can implement particle
systems and other non-static things.

1 files changed, 24 insertions, 29 deletions

diff --git a/examples/life.scm b/examples/life.scm
index 2842690..2d4e30a 100644
--- a/examples/life.scm
+++ b/examples/life.scm
@@ -1,6 +1,6 @@
 ;;; Life, Sly edition
 ;;; Copyright (C) 2015 Christopher Allan Webber <cwebber@dustycloud.org>
-;;; Copyright (C) 2014 David Thompson <davet@gnu.org>
+;;; Copyright (C) 2014, 2015 David Thompson <davet@gnu.org>
 ;;;
 ;;; This program is free software: you can redistribute it and/or
 ;;; modify it under the terms of the GNU General Public License as
@@ -30,11 +30,10 @@
              (sly math rect)
              (sly math transform)
              (sly math vector)
+             (sly render)
              (sly render camera)
-             (sly render model)
              (sly render sprite)
              (sly render color)
-             (sly render scene)
              (sly input mouse))
 
 ;;;
@@ -68,15 +67,17 @@
 (define tile-size 32)
 (define window-res (vector2 448 480))
 
+(define alive-texture
+  (load-texture "mines/images/tile-down.png"))
+
+(define empty-texture
+  (load-texture "mines/images/tile-up.png"))
+
 (define sprite-cell-alive
-  (load-sprite
-   "mines/images/tile-down.png"
-   #:anchor 'bottom-left))
+  (make-sprite alive-texture #:anchor 'bottom-left))
 
 (define sprite-cell-empty
-  (load-sprite
-   "mines/images/tile-up.png"
-   #:anchor 'bottom-left))
+  (make-sprite empty-texture #:anchor 'bottom-left))
 
 ;;;
 ;;; State
@@ -106,10 +107,7 @@
 ;; Give a heartbeat indicating it's time to run an evolution on the board
 ;; (if the simulation is running)
 (define-signal time-to-evolve
-  (signal-map
-   (lambda _
-     'evolve)
-   (signal-every 20)))
+  (signal-constant 'evolve (signal-every 20)))
 
 (define (tile-on-board? x y board-size)
   "Is the tile on the board?"
@@ -295,17 +293,18 @@ If there is no neighbor on an edge, the board wraps around"
 (define-signal tiles-view
   (signal-let ((board board)
                (board-size board-size))
-    (list->model
+    (list->renderer
      (enumerate-map
       (lambda (row row-count)
-        (list->model
+        (list->renderer
          (enumerate-map
           (lambda (tile-alive col-count)
-            (model-move (tile-pos row-count col-count
-                                  board-size tile-size)
-                        (if tile-alive
-                            sprite-cell-alive
-                            sprite-cell-empty)))
+            (move (tile-pos row-count col-count
+                            board-size tile-size)
+                  (render-sprite
+                   (if tile-alive
+                       sprite-cell-alive
+                       sprite-cell-empty))))
           (vlist->list row))))
       ;; FIXME:
       ;; This slows things down more than it should have to
@@ -314,17 +313,13 @@ If there is no neighbor on an edge, the board wraps around"
 
 (define-signal camera
   (signal-let ((running? simulation-running?))
-    (orthographic-camera
-     (vx window-res) (vy window-res)
-     #:viewport (make-viewport (make-rect (vector2 0 0) window-res)
-                               #:clear-color (if running?
-                                                 tango-dark-chameleon
-                                                 tango-dark-scarlet-red)))))
+    (2d-camera #:area (make-rect (vector2 0 0) window-res)
+               #:clear-color (if running?
+                                 tango-dark-chameleon
+                                 tango-dark-scarlet-red))))
 
 (define-signal scene
-  (signal-let ((model  tiles-view)
-               (camera camera))
-    (make-scene camera model)))
+  (signal-map with-camera camera tiles-view))
 
 ;;;
 ;;; Initialization