examples: Add sprite batch example.

* examples/sprite-batch.scm: New file.

1 files changed, 62 insertions, 0 deletions

diff --git a/examples/sprite-batch.scm b/examples/sprite-batch.scm
new file mode 100644
index 0000000..3ced4ed
--- /dev/null
+++ b/examples/sprite-batch.scm
@@ -0,0 +1,62 @@
+;;; Sly
+;;; Copyright © 2016 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
+;;; published by the Free Software Foundation, either version 3 of the
+;;; License, or (at your option) any later version.
+;;;
+;;; This program is distributed in the hope that it will be useful,
+;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;; General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with this program.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
+(use-modules (sly)
+             (sly render sprite-batch)
+             (srfi srfi-1))
+
+(load "common.scm")
+
+(define (make-sprite-rects size texture)
+  (let ((width (texture-width texture))
+        (height (texture-height texture)))
+    (list-tabulate size
+                   (lambda _
+                     (make-rect (- (random 640) 32) (- (random 480) 32)
+                                width height)))))
+
+(define (render-sprites batch texture rects)
+  (lambda (gfx)
+    (with-sprite-batch batch gfx
+      (for-each (lambda (rect)
+                  (sprite-batch-add! batch gfx texture rect))
+                rects))))
+
+(define-signal size 1000)
+
+(define-signal sprites
+  (let ((texture (on-start (load-texture "images/p1_front.png"))))
+    (signal-map-maybe render-sprites
+                      (signal-map (lambda (size started?)
+                                    (and started? (make-sprite-batch size)))
+                                  size game-started?)
+                      texture
+                      (signal-map-maybe make-sprite-rects size texture))))
+
+(define-signal scene
+  (signal-let ((sprites sprites))
+    (if sprites
+        (with-camera (2d-camera #:area (make-rect 0 0 640 480))
+          sprites)
+        render-nothing)))
+
+(with-window (make-window #:title "Sprite Batch")
+  (run-game-loop scene))
+
+;;; Local Variables:
+;;; compile-command: "../pre-inst-env guile sprite-batch.scm"
+;;; End: