+Framebuffer::Attachment &Framebuffer::get_or_create_attachment(FramebufferAttachment attch)
+{
+ for(vector<Attachment>::iterator i=attachments.begin(); i!=attachments.end(); ++i)
+ if(i->attachment==attch)
+ return *i;
+ attachments.push_back(Attachment(attch));
+ return attachments.back();
+}
+
+void Framebuffer::check_size()
+{
+ if(!attachments.empty())
+ {
+ const Attachment &attch = attachments.front();
+ if(attch.type==GL_RENDERBUFFER_EXT)
+ {
+ width = attch.rbuf->get_width();
+ height = attch.rbuf->get_height();
+ }
+ else if(attch.type==GL_TEXTURE_2D)
+ {
+ Texture2D *tex = static_cast<Texture2D *>(attch.tex);
+ width = tex->get_width();
+ height = tex->get_height();
+ }
+ if(cur_fbo==this)
+ viewport(0, 0, width, height);
+ }
+}
+
+const Framebuffer *Framebuffer::cur_fbo = 0;
+int Framebuffer::sys_viewport[4] = { 0, 0, 1, 1 };
+
+
+Framebuffer::Attachment::Attachment(FramebufferAttachment a):
+ attachment(a),
+ type(0)
+{ }
+
+Framebuffer::Attachment &Framebuffer::Attachment::operator=(Renderbuffer &r)
+{
+ type = GL_RENDERBUFFER_EXT;
+ rbuf = &r;
+ return *this;
+}
+
+Framebuffer::Attachment &Framebuffer::Attachment::operator=(Texture &t)
+{
+ type = t.get_target();
+ tex = &t;
+ return *this;
+}
+
+
+void viewport(int x, int y, unsigned w, unsigned h)
+{
+ glViewport(x, y, w, h);
+}
+
+void clear(BufferBits bits)
+{
+ glClear(bits);
+}
+
+void draw_buffer(RWBuffer buf)
+{
+ glDrawBuffer(buf);
+}
+
+void read_buffer(RWBuffer buf)
+{
+ glReadBuffer(buf);
+}