Frame

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Syntax

Syntax legend
< ... > item
[ ... ] optional
( ... ) * 0 or more times
( ... ) + 1 or more times

Frame [ ( <percentage> ) ] ;




Description

The frame; command tells the interpreter when a process is done for one game cycle. When the frame; is reached, the screen is updated. If there are several processes running, the screen is updated once every process has reached its frame; statement.

It is commonly used in loops of processes that should do something like moving around by a certain amount of pixels per game cycle (or per frame).

A possibility is to adjust the amount of cycles to wait. frame(100); would wait one cycle (100%), same as frame;. However frame(200); will wait two cycles (200% means the frame statement provides for 200% frame). So frame(50); will wait a half cycle or otherwise said, it will make a loop run twice per frame.

Example

Process Main()
Begin

    square();

    Repeat
        frame;
    Until(key(_ESC))

    exit();

End

Process square()
Begin

    graph = new_map(5,5,16);
    map_clear(0,graph,rgb(255,255,255));

    Loop
        x += 2 * (key(_right)-key(_left));
        frame; //<-vital part
    End

End

This example process would give you a square you can move around the screen by 2 pixel before it gets showed again, before the game cycle is over, before the frame; happens. If there would be no frame; in the loop, it would just run forever and the interpreter would wait forever for the frame;, which would result in freezing.


Keywords
Basic statement BEGINCONSTDEBUGDECLAREENDFUNCTIONGLOBALLOCALONEXITPRIVATEPROCESSPROGRAMPUBLIC
Control flow statements BREAKCALLCASECONTINUEDEFAULTELIFELSEELSEIFELSIFFORFRAMEFROMGOTOIFJMPLOOPREPEATRETURNSTEPSWITCHTOUNTILWHILEYIELD
Misc INCLUDEIMPORT