Fix overriding requested fbo sizes

pipeline.lisp

@@ -61,8 +61,11 @@
         do (multiple-value-bind (width height) (texspec-real-size texspec width height)
              (resize texture width height)))
   (loop for pass across (passes pipeline)
-        do (setf (width (framebuffer pass)) width)
-           (setf (height (framebuffer pass)) height)))
+        for binding = (first (attachments (framebuffer pass)))
+        when binding ;; We have to do it like this to prevent updating FBOs with
+                     ;; texspecs that are not window-size.
+        do (setf (width (framebuffer pass)) (width (second binding)))
+           (setf (height (framebuffer pass)) (height (second binding)))))
 
 (defmethod normalized-texspec ((texspec list))
   (assert (= 0 (getf texspec :level 0)))