+
+# Optimized `GroupedArray` to use `Sprite::context_index` and avoid using `index_of`
+private class GroupedSprites
+ super GroupedArray[Sprite]
+
+ redef fun add(item)
+ do
+ var index = super
+ item.context_index = index
+ return index
+ end
+
+ redef fun remove(item) do remove_at(item, item.context_index)
+end
+
+redef class GLfloatArray
+ private fun fill_from_matrix(matrix: Matrix, dst_offset: nullable Int)
+ do
+ dst_offset = dst_offset or else 0
+ var mat_len = matrix.width*matrix.height
+ assert length >= mat_len + dst_offset
+ native_array.fill_from_matrix_native(matrix.items, dst_offset, mat_len)
+ end
+end
+
+redef class NativeGLfloatArray
+ private fun fill_from_matrix_native(matrix: matrix::NativeDoubleArray, dst_offset, len: Int) `{
+ int i;
+ for (i = 0; i < len; i ++)
+ self[i+dst_offset] = (GLfloat)matrix[i];
+ `}
+end