SilverScreen Basics

Drawings, Screens and Windows

The fundamental document in SilverScreen is a drawing (.DRW). A drawing contains geometry and information related to that geometry.

A screen is a viewing area that is composed of tiled windows, and possibly containing overlay windows that overlap the underlying tiled windows. Drawings are viewed by associating them with a window within a screen.

SilverScreen maintains a list of drawings, and a list of screens. Each screen maintains its own list of the windows that comprise the screen, and each window refers to the drawing that is displayed in the window.

SilverScreen Screen/Window/Drawing Architecture

Screens

Screens are accessed by name.  The name of the currently active screen is obtained by using the function sys_screen. A list of the current screens may be obtained by using the function collect_generic( GN_SCREENS, … ), and their names may then be obtained by using get_generic. Screen dimensions are 0-based from the top-left corner: to obtain the width and height of the currently active screen, use the variables vpixel_right and vpixel_bot. To change to a different screen using its name, use the command SCREEN GOTO <screen-name>.

Windows

SilverScreen windows are accessed by window number. Numbers are assigned automatically by the system, and may be changed when certain operations occur, particularly those that create or destroy new windows on the screen. Window numbers are 1-based, and the highest window number on the screen is the number of windows on the screen. The currently active window (in the currently active screen) is obtained by using sys_window. The number of windows on the current screen is given by count_windows. To change to a different window using its number, use the command WINDOW GOTO <window-number>.

Drawings

Drawings are not directly accessible. The name of the current drawing (that is, the drawing loaded in the current window on the current screen) is obtained by using the function sys_drawing. Drawing attributes may be obtained by various means. To access the current drawing’s geometry, you may obtain the root block by using get_block( “\\” ).