** 0.5 page STOS Corner / 494 words **
Get in CONTROL!

Martin Milner takes a look at the facilities offered by Les Greenhalgh's CONTROL extension (v3.6 registered)...

At its simplest the CONTROL extension provides a number of commands which can be used to improve the structure of your programs, (for example case and switch), a command to write strings of text anywhere in memory (write), a command to add one variable to another, but keep it within a specified range (add(a,i,l,r)), commands to move and restore the cursor position (cmove, cremember and crecall) and the useful exist$ which can be used to check whether files exist.

Also contained are a number of commands to drive joysticks plugged into the parallel port via a special adapter, zone commands which allow up to 65536 zones to be defined, a command to un/pack Crack Art screens, a palette manipulation command (spread), a command to remove the screen borders on an STFM (brdr remove), a 'quick screen$' command (much faster than its STOS equivalent) and the command hscroll which performs smooth horizontal scrolling on a standard 320x200 sized screen.

Delving deeper reveals a wealth of very powerful commands. For example:
** bulleted list **
* The extension contains a complete sprite engine which is much faster than the original STOS one and has the ability to flip sprites vertically. This means you might not need both upward and downward facing sprites.  Clipping and collision detection commands are provided, as are commands to get sprite sizes and palettes.
* A complete set of mapping commands are provided which are not restricted to using 16x16 pixel blocks unlike the Missing Link commands. An accessory is provided which enables you to design your own maps. It is even easier to use than the Missing Link map editor and uses the concept of layers.
** end list **
An accessory is supplied which enables banks of sprites, blocks or fonts to be created very easily. The biggest advantage of all the sprite and map commands is they can work on non-standard screen sizes, so you are no longer restricted to 320x200 (ST low resolution). The extension also contains commands to set large virtual screen sizes and to use the blitter along with hardware scrolling in all directions on suitably equipped machines. You can also use the blitter to copy large sections of memory around (bigcopy) or clear it using bigcls. A command is also provided to allow you to write 16 colour fonts from image banks onto large size screens.

A number of the commands are only available to registered users including:
** Bulleted list **
* jagjoy command enables your programs to support the jaguar joypad controller
* turbocopy is an ultra fast 320x200 screen copier
* Many other advanced mapping and sprite commands
** end list **

Considering the amount of work involved and the support Les provides to registered users, registration is a must.

Next issue I'll be taking a look at the latest versions of Anthony Hoskins excellent Falcon extensions.