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Rockbox mail archiveSubject: For Comment and Trial: "Alternating WPS Lines" Proposed WPS extensionFor Comment and Trial: "Alternating WPS Lines" Proposed WPS extension
From: c s <rb_dev_at_yahoo.com>
Date: Thu, 17 Apr 2003 20:47:04 -0700 (PDT) I wanted a better way other than using very long scrolling lines to display all the information that I wanted to see on wps within the limited player display space, so I decided to extend the functionality of the wps to accomplish this. I have summarized what I have done to solicit input from anyone who would like to try it out and/or make any comments or suggestions. My wps extension introduces a concept of alternating "sub-lines". An alternating sub-line is defined as a wps format line which will be displayed on one line of the wps for a specified time, followed by one or more additional wps format lines which will be displayed on the line for a specified time. Every line of the wps can have it's own group of sub-lines that are each displayed for a specified time. The display presented on the wps for each line will consist of the alternating consecutive display of each sub-line defined for that line. The sub-line concept is similar to specifying several formats on one line and using scrolling so that they all can be seen, except that sub-lines are more powerful in the following ways: 1) Sub-lines that fit the width of the LCD will not scroll but will simply be displayed on the line until the next sub-line item is displayed (however sub-lines that are longer than the width of the LCD can still be scrolled). 2) Sub-lines can combine any wps formats, so you can now display a non-scrollable format such as track elapsed time followed by a scrolled format on the same line. 3) The user has control over how long each sub-line item is displayed before the next item is displayed. For example, on one line you can: a. Display the Artist and Title ID3 tags for 5 seconds (scrolled), and then.... b. Display file bit rate and file frequency for 1 second (not scrolled), and then.... c. Display track elapsed time for 2 seconds (not scrolled), and then repeat the cycle. 4) The ability to control the time that each item is displayed and the fact that long lines can be split into smaller sub-lines that can be displayed with or without scrolling makes for a display where each individual item is much easier to read than if they were all specified on one long line that is continuously scrolled. -------------------------------- Changes To The WPS Format Specification This wps extension is backward compatible with the current wps specification. Current wps definitions will still display the same as they do now. The wps format specification language is extended as follows: 1) The ';' character is used to separate items on a line into sub-lines. 2) The "%t[0-9]" tag is used to specify a time 0-9 (seconds) for the sub-line to be displayed before the next sub-line is displayed. (example: %t3) 3) The "%;" tag can be used to escape the special meaning of the ';' character and display a ';' character on wps line. Example wps sub-line specifications: %s%t5%ia - %it;%t1%fb;%t2%pc %pr This will display the artist and title ID3 tags for 5 seconds (scrolled if it's longer than the display width), then display the file bit rate for 1 second (not scrolled), then display the track current and remaining time for 2 seconds (not scrolled). Conditionals can be used within sub-line specifications just as they are currently used for single line specifications. Here is a more complex sub-line specification that uses conditionals (note that this is all one line although it may be wrapped in this message): %?ia<%t6%s%it by %ia|%t1No ID3 Info>;%?ia<%t0|%t5%sFilename:%fn>;%t1%fb kbps;%t1%ffHz The format above will do two different things depending if the artist ID3 tag is present: If the Artist ID3 tag is defined, the wps line will appear as follows: "<ID3 title> by <ID3 artist>" displays for 5 seconds (scrolled) "<file bitrate> kbps" displays for 1 second "<file frequency>Hz displays for 1 second If the Artist ID3 tag is not defined, the wps line will appear as follows: "No ID3 Info" displays for 1 second "Filename:<filename>" displays for 5 seconds (scrolled) "<file bitrate> kbps" displays for 1 second "<file frequency>Hz displays for 1 second Note that with the use of conditionals and using a sub-line time of 0 inside the condition branch, a different number of sub-lines can be displayed on the line depending on the branch taken for the conditional. --------------------------- This extension to the wps specification is primarily useful for the player where you only have 2 lines of 11 characters, but there is nothing player specific in the implementation and it should work on the recorder also. Although there are still a few improvements I plan to add to this, I am presenting what I have working now to solicit comments from the group and inquire if anyone finds this useful and would like to see it submitted to be considered for inclusion in the CVS. The source code still needs to be cleaned up before I make it available, but if anyone wants to try out what I have so far, executables are available at: http://home.pacbell.net/csath I need someone to test it on a Recorder as I only have a Player for testing. ===== Craig rb_dev_at_yahoo.com __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! http://platinum.yahoo.com Received on 2003-04-18 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |