MATRIX 1                MATRIX 2
+-------------------+--------------------------+ 
+ m1c1r7 ... m1c5r7 + m2c1r7 m2c2r7 ... m2c5r7 +
+ m1c1r6 ... m1c5r6 + m2c1r6 m2c2r6 ... m2c5r6 +
+ ................. + ........................ +
+ m1c1r1 ... m1c5r1 + m2c1r1 m2c2r1 ... m2c5r1 +
+-------------------+--------------------------+
   C_A        C_B      C_C    C_D        C_E     <- before scroll

              C_C      C_D                       <- after scroll