+// Create a VBO with the given data, and bind it to the vertex attribute
+// with name <attribute_name>. Returns the VBO number.
+GLuint fill_vertex_attribute(GLuint glsl_program_num, const std::string &attribute_name, GLint size, GLenum type, GLsizeiptr data_size, const GLvoid *data);
+
+// Clean up after fill_vertex_attribute().
+void cleanup_vertex_attribute(GLuint glsl_program_num, const std::string &attribute_name, GLuint vbo);
+
+// If v is not already a power of two, return the first higher power of two.
+unsigned next_power_of_two(unsigned v);
+
+// Get a pointer that represents the current OpenGL context, in a cross-platform way.
+// This is not intended for anything but identification (ie., so you can associate
+// different FBOs with different contexts); you should probably not try to cast it
+// back into anything you intend to pass into OpenGL.
+void *get_gl_context_identifier();
+
+} // namespace movit
+