80-Bus News


September–October 1984, Volume 3, Issue 5

Page 25 of 47


Opcode Description.
1 Initialise Workstation. Loads the device driver if necessary and sets default values.
2 Close Workstation. Halts graphics output to this workstation.
3 Clear Workstation. This clears the device and is equivalent to CLS if used on a CRT device.
4 Update Workstation. Display all pending graphics.
5 Escape. Enable device dependent operation. These deal mainly with character output if the device has an alpha mode with addressable character cells. Function 5 is called and an escape sequence ID is passed to GSX in control(6).
1Inquire addressable character cells.
2Enter graphics mode.
3Exit graphics mode.
4Alpha cursor up.
5Alpha cursor down.
6Alpha cursor right.
7Alpha cursor left.
8Home alpha cursor.
9Erase to end of screen.
10Erase to end of line.
11Direct cursor address ( Move to row and column).
12Output cursor addressable text.
13Reverse video on.
14Reverse video off.
15Inquire current cursor address.
16Inquire tablet status. ( Is a digitiser connected?)
17Hard copy. e.g. Dump a graphics screen to printer.
18Place graphics cursor at location.
19Remove graphics cursor. This turns the cursor off.
2050       Reserved for future expansion.
51100     Unused and available.
6 Polyline. Output lines from data in PTSIN array.
7 Polymarker. Output markers at positions given in PTSIN. These markers are typically ( . * O X + ).
8 Text. Output text from machine font at specified position.
9 Filled area. Display and fill a polygon.
10 Cell array. Create a pixel array from colour data given in the INTIN array and at a position given in PISIN.


Opcode Description.
11 Generalised drawing primitive. These routines give you an easy way to display bars, arcs, pie slices and circles. These are not always fully implemented.
12 Set character height. Not possible of course if the Pluto font is used but should be implemented for plotter device drivers and the suchlike.
13 Set character up vector. This allows you to rotate character strings if the device will allow it.
14 Set colour representation. Will allow you to specify the red, green and blue intensity associated with a colour index. (Presumably this is for use in palette systems.)
15 Set linetype. You should be able to choose from solid, dashed, dotted or dashed=dotted.
16 Set line width.
17 Set line colour.
18 Set marker type.
19 Set marker scale.
20 Set marker colour.
21 Set hardware text font. (Only one to choose from in Pluto.)
22 Set text colour.
23 Set fill interior style. You should be able to choose from outline only, solid fill, pattern fill or hatch pattern fill.
24 Set fill style index. This allows you to specify the type of pattern or hatch fill you require from the selection available.
25 Set fill colour index, Having chosen the type of fill you require you can now say what colour you want it done in.
26 Inquire colour representation. Returns the RGB intensities of a requested colour index.
27 Inquire cell array. Returns the pixel colour values of the requested area.

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