1 files changed, 20 insertions, 15 deletions
diff --git a/chickadee/graphics/buffer.scm b/chickadee/graphics/buffer.scm
index cfb541f..9e5a791 100644
--- a/chickadee/graphics/buffer.scm
+++ b/chickadee/graphics/buffer.scm
@@ -571,7 +571,7 @@ argument may be overridden.  The following values are supported:
                 ((index . buffer-view)
                  (apply-buffer-view buffer-view index)))
               attributes)
-    (apply-buffer-view indices)
+    (when indices (apply-buffer-view indices))
     (set-gpu-vertex-array! (current-gpu) null-vertex-array)
     array))
 
@@ -585,21 +585,26 @@ argument may be overridden.  The following values are supported:
     ('triangle-strip (begin-mode triangle-strip))
     ('triangle-fan (begin-mode triangle-fan))))
 
-(define* (render-vertices array #:optional count)
+(define* (render-vertices array #:key count (offset 0))
   (set-gpu-vertex-array! (current-gpu) array)
   (let ((indices (vertex-array-indices array)))
-    (gl-draw-elements (vertex-array-mode-gl array)
-                      (or count
-                          (buffer-view-length indices))
-                      (buffer-view-type-gl indices)
-                      %null-pointer)))
-
-(define* (render-vertices/instanced array instances #:optional count)
+    (if indices
+        (gl-draw-elements (vertex-array-mode-gl array)
+                          (or count
+                              (buffer-view-length indices))
+                          (buffer-view-type-gl indices)
+                          %null-pointer)
+        (gl-draw-arrays (vertex-array-mode-gl array) offset count))))
+
+(define* (render-vertices/instanced array instances #:key count (offset 0))
   (set-gpu-vertex-array! (current-gpu) array)
   (let ((indices (vertex-array-indices array)))
-    (gl-draw-elements-instanced (vertex-array-mode-gl array)
-                                (or count
-                                    (buffer-view-length indices))
-                                (buffer-view-type-gl indices)
-                                %null-pointer
-                                instances)))
+    (when indices
+      (gl-draw-elements-instanced (vertex-array-mode-gl array)
+                                  (or count
+                                      (buffer-view-length indices))
+                                  (buffer-view-type-gl indices)
+                                  %null-pointer
+                                  instances)
+      (gl-draw-arrays-instanced (vertex-array-mode-gl array)
+                                offset count instances))))