gamnit: don't overflow `short int` used as vertices index

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/lib/gamnit/flat.nit b/lib/gamnit/flat.nit
index 56fd402..f8cd42e 100644 (file)
--- a/lib/gamnit/flat.nit
+++ b/lib/gamnit/flat.nit
@@ -873,7 +873,7 @@ private class SpriteSet
        super HashSet[Sprite]
 
        # Map texture then static vs dynamic to a `SpriteContext`
-       var contexts_map = new HashMap3[RootTexture, nullable RootTexture, Bool, SpriteContext]
+       var contexts_map = new HashMap3[RootTexture, nullable RootTexture, Bool, Array[SpriteContext]]
 
        # Contexts in `contexts_map`
        var contexts_items = new Array[SpriteContext]
@@ -897,13 +897,29 @@ private class SpriteSet
                var animation = sprite.animation
                var animation_texture = if animation != null then
                        animation.frames.first.root else null
-               var context = contexts_map[texture, animation_texture, sprite.static]
+               var contexts = contexts_map[texture, animation_texture, sprite.static]
+
+               var context = null
+               if contexts != null then
+                       for c in contexts.reverse_iterator do
+                               var size = c.sprites.length + 1
+                               if size * 4 <= 0xffff then
+                                       context = c
+                                       break
+                               end
+                       end
+               end
 
                if context == null then
                        var usage = if sprite.static then gl_STATIC_DRAW else gl_DYNAMIC_DRAW
                        context = new SpriteContext(texture, animation_texture, usage)
 
-                       contexts_map[texture, animation_texture, sprite.static] = context
+                       if contexts == null then
+                               contexts = new Array[SpriteContext]
+                               contexts_map[texture, animation_texture, sprite.static] = contexts
+                       end
+
+                       contexts.add context
                        contexts_items.add context
                end