User Guide

Creating a Bitwise Compare Routine 225
The only way to get a non-zero, or true, result is if both bits at the same location have a non-
zero value. For example...
SPRM Value 10110011
Bitwise Compare 10000000
Result 10000000 = True
In this case, the True result means the subpicture stream is on-screen. If the SPRM2 value at
the seventh bit were anything else, the result would be zero and therefore False. In
Scenarist, you work in decimal numbers, not binary, so in the above example you would be
comparing an SPRM value of 91 to a Bitwise Compare of 64.
Creating a Bitwise Compare Routine
For the following exercise you will create a menu with three buttons (labeled Button 1,
Button 2, and Button 3) and three short videos. The objective of the exercise is to create a
title menu in which the viewer must activate Button 1 and Button 2 before Button 3 can be
activated. To accomplish this, you will add button highlights that link to three titles (Video 1,
Video 2, and Video 3), assign GPRMs to Button 1 and Button 2, add a Bitwise Compare to
Button 3, and add a Post command to each title that returns play to the title menu.
This section includes the following topics:
• “Linking the Highlight Buttons to the Three Videos” on page 226
• “Assigning GPRMs to Title_1 and Title_2” on page 227
• “Assigning a Bitwise Compare to Title_3” on page 228
• “Adding a Post Command to Each Title” on page 229