Add optional texture coordinate parameters to texture-quad and sprite-batch-draw.

2 files changed, 13 insertions, 11 deletions

diff --git a/2d/sprite.scm b/2d/sprite.scm
index bcf09b6..5a0cf00 100644
--- a/2d/sprite.scm
+++ b/2d/sprite.scm
@@ -187,8 +187,9 @@
 ;; TODO add transformation logic for scaling and rotating.
 ;; TODO add support for colors
 ;; TODO add support for different blending modes.
-(define (sprite-batch-draw batch texture x y center-x center-y
-                           width height scale-x scale-y rotation)
+(define* (sprite-batch-draw batch texture x y center-x center-y
+                            width height scale-x scale-y rotation
+                            #:optional (u 0) (v 0) (u2 1) (v2 1))
   ;; Render the batch when it's full or the texture changes.
   (cond ((= (sprite-batch-size batch) (sprite-batch-max-size batch))
          (sprite-batch-render batch))
@@ -204,19 +205,19 @@
     (pack vertices base sprite-vertex
           x y
           1 1 1 1
-          0 0)
+          u v)
     (pack vertices (+ base 1) sprite-vertex
           x2 y
           1 1 1 1
-          1 0)
+          u2 v)
     (pack vertices (+ base 2) sprite-vertex
           x2 y2
           1 1 1 1
-          1 1)
+          u2 v2)
     (pack vertices (+ base 3) sprite-vertex
           x y2
           1 1 1 1
-          0 1))
+          u v2))
   ;; Increment batch size
   (set-sprite-batch-size! batch (1+ (sprite-batch-size batch))))
 
diff --git a/2d/texture.scm b/2d/texture.scm
index 0db72a2..2276025 100644
--- a/2d/texture.scm
+++ b/2d/texture.scm
@@ -108,20 +108,21 @@ Currently only works with RGBA format surfaces."
   "Loads a texture from a file."
   (surface->texture (SDL:load-image filename)))
 
-(define* (texture-quad texture x y w h #:optional (color '(1 1 1)))
+(define* (texture-quad texture x y w h #:optional (color '(1 1 1))
+                       (u 0) (v 0) (u2 1) (v2 1))
   "Renders a textured quad."
   (let ((x2 (+ x w))
         (y2 (+ y h)))
     (with-gl-bind-texture (texture-target texture-2d) (texture-id texture)
       (gl-begin (begin-mode quads)
         (apply gl-color color)
-        (gl-texture-coordinates 0 0)
+        (gl-texture-coordinates u v)
         (gl-vertex x y)
-        (gl-texture-coordinates 1 0)
+        (gl-texture-coordinates u2 v)
         (gl-vertex x2 y)
-        (gl-texture-coordinates 1 1)
+        (gl-texture-coordinates u2 v2)
         (gl-vertex x2 y2)
-        (gl-texture-coordinates 0 1)
+        (gl-texture-coordinates u v2)
         (gl-vertex x y2)))))
 
 ;;;