ReTargetable Graphics

ReTargetable Graphics, (abbreviated as RTG), is a device driver API mainly used by third-party graphics hardware to interface with AmigaOS via a set of libraries.^[1] The software libraries may include software tools to adjust resolution, screen colors, pointers and screenmodes. It will use available hardware and will not extend the capabilities in any way.

The Amiga OS 3.x intuition.library is limited to 8-bit display depths, but RTG libraries make it possible to handle higher depths such as 24 bits; on Amiga there are two common APIs: Picasso 96 and CyberGraphX, which are almost compatible with each other. Both of Picasso 96 and CyberGraphX required at least 4MB RAM and 68020 CPU to operate.

EGS and other early graphics card drivers

Although Commodore planned to introduce retargetable graphics in future version of AmigaOS (4.0),^[2] the company was not able to deliver such solution before its demise. Third party graphics cards manufacturers thus were forced to create their own software layers on top of AmigaOS, incompatible to each other. Most of these early Amiga graphics card drivers shared common limitations: compatibility with current applications was maintained by opening Workbench (or also other application screens, also called as "Workbench emulation") on the graphics card - usually in 16 (under AmigaOS 2.x) or 256 colours (under AmigaOS 3.x); full graphics card features like Hi-Colour and True-Colour display could be used only by applications directly programmed for such driver software. Examples of similar solutions are EGS, Merlin/Domino,^[3] Omnibus,^[4] Retina^[5] (which should be able even to display Workbench in 24 bit colour),^[6] Graffity,^[7] Picasso and ProBench. Of these, Picasso offered good compatibility with older applications, because most OS compliant programs could be promoted to graphics card display,^[8] and relatively strong software support.^[1] ProBench (by ProDev) was released as new "Workbench emulator" for the old Merlin graphics card in 1994,^[9] version 3 (1996) introduced 16 bit colour depth and compatibility with CyberGraphX.^[10][11]

Enhanced Graphics System (EGS) was developed by Viona Development written in Cluster (a Modula-2 derivate) for Piccolo and Spectrum graphics boards supporting screen depths up to 24 bits. It requires a minimum of 2 MByte RAM and 4 - 5 MByte of hard disk space.^[12] EGS was first presented with the EGS 110/24 card (GVP) at the World of Commodore/Amiga show in New York in April 1992.^[13] It supported broader range of graphics cards than other drivers and was seen by some Amiga magazines as the next RTG standard for Amiga, but its compatibility with most Amiga applications was limited.^[14][15][16]

CyberGraphX

CyberGraphX (pronounced "cybergraphics"), is a ReTargetable Graphics API for the Amiga and compatible computer systems developed by Thomas Sontowski and Frank Mariak and later adopted by Phase5 for use with their graphics cards.^[17] Many other graphics card manufacturers that offered hardware for Amiga and compatible systems used it, as well.

Introduced in 1995 with CyberVision64 graphics card (Phase5), Cybergraphics was the first RTG software to allow full True-Colour screens for Workbench and applications - older solutions supported only 256 colours (eg. Picasso) or four colour Workbench with some 24 bit windows (Retina).^[18] CyberGraphX quickly eclipsed all older graphics card drivers and was acclaimed already in 1995 as the best solution for displaying Workbench and other applications. Being available free of charge for users of supported cards, it became de facto RTG standard for Amiga.^[19] CyberGraphX V4^[20] was the last release for AmigaOS, MorphOS uses CyberGraphX V5.

Supported graphic cards

These graphic cards are supported by CyberGraphX:

Picasso 96

Picasso 96 is the RTG device driver library set used by the Picasso IV and other graphics boards. Its development was started in 1996 by Village Tronic and is CyberGraphX compatible.^[22] Although first releases were ridden with bugs and stability problems,^[23] by version 1.17 Picasso 96 corrected most issues and improved compatibility with CyberGraphX.^[24]

Picasso 96 was selected as RTG standard for AmigaOS 4. At first released as 68k binary in AmigaOS 4.0 pre-release,^[25] with full PowerPC port following later in 2004 in the next OS update.^[26] AmigaOS 4.1 Final Edition (2014) integrated RTG functions directly into graphics.library.

Supported graphic cards

These graphic cards are supported by Picasso96 system.

Picasso96 as used by AmigaOS 4 supports also Voodoo 3, Voodoo 4/5 and Radeon R100, R200, R300 ^[27] , R520 (X1000 Series), R700 (HD 4000 Series), HD 5000 (Evergreen) series, HD 6000 (Northern Islands) series and HD 7000 (Southern Islands) series.^[28] The RadeonHD AmigaOS 4 driver has been developed by Hans de Ruiter^[29] and exclusively funded by and licensed to A-EON Technology Ltd.

See also

• AmigaOS Graphics

External links

• amiga-hardware.com - Graphics Cards (RTG)
• pcguru.plus.com - How to configure Picasso96 for AmigaOS 3.x

References

1. 1 2 Goodwin, Simon (September 1997). "RTG". Amiga Format. No. 101. Future Publishing. pp. 24–27. ISSN 0957-4867. 
2. ↑ Leemon, Sheldon (February 1993). "Devices & Desires, The Future: Retargetable Graphics". Amiga World. Vol. 9 no. 2. IDG Publishing. p. 38. ISSN 0883-2390. 
3. ↑ Janin, Lucas (March 1993). "Domino". AmigaNews (in French). No. 55. NewsEdition. pp. 48–49. ISSN 1164-1746. 
4. ↑ Roman, Times (April 1993). "Notes From The Nets, More Graphics, Goodies". Amiga News. Vol. 2 no. 3. Portable Computing International. p. 6. ISSN 1063-8458. 
5. ↑ Nakakihara, Douglas J. (October 1993). "Retina". Amazing Computing. Vol. 8 no. 10. PiM Publications. pp. 14–15. ISSN 0886-9480. 
6. ↑ Ryan, John (July 1993). "Retina". Amiga World. Vol. 9 no. 7. IDG Publishing. pp. 68–69. ISSN 0883-2390. 
7. ↑ "En bref, BSC, Graffity". AmigaNews (in French). No. 61. NewsEdition. October 1993. p. 8. ISSN 1164-1746. 
8. ↑ Atkin, Denny (January 1994). "Picasso II". Amiga World. Vol. 10 no. 1. IDG Publishing. pp. 16–18. ISSN 0883-2390. 
9. ↑ Ulrich Flegel (June 16, 1994). "X-Pert is dead - Merlin alive". Newsgroup: comp.sys.amiga.hardware. Usenet: 1994Jun16.113448@ibr.cs.tu-bs.de. Retrieved November 26, 2016. 
10. ↑ "ProBench 3 documentation in english" (AmigaGuide in lha archive). aminet.net. October 21, 1996. Retrieved November 26, 2016. 
11. ↑ "ProBench v3.0". Amiga Info (in Swedish). Vol. 1 no. 6. X-Files Media. 1996. ISSN 1401-4661. 
12. ↑ "EGS FAQ". Amiga Report International Online Magazine. Vol. 2 no. 5. February 4, 1994. Retrieved 2016-11-23. 
13. ↑ Atkin, Denny (July 1992). "GVP Steal the show". Amiga Computing. No. 50. Europress Publications. p. 14. ISSN 0959-9630. 
14. ↑ Kennedy, Stevie (Christmas 1993). "Bundle of joy, Piccolo graphics card". Amiga Computing. No. 68. Europress Publications. pp. 60–61. ISSN 0959-9630. 
15. ↑ Johnson, Dave (April 1994). "EGS 28/24 Spectrum". Amiga World. Vol. 10 no. 4. IDG Publishing. pp. 12–13. ISSN 0883-2390. 
16. ↑ Janin, Lucas (May 1995). "Piccolo-SD64". AmigaNews (in French). No. 79. NewsEdition. pp. 20–21. ISSN 1164-1746. 
17. ↑ Němec, Luboš (January 1996). "CyberVision64 & CyberGraphX (podruhé)". Amiga Review (in Czech). No. 12. Atlantida Publishing. pp. 17–19. ISSN 1211-1465. 
18. ↑ Austin, Paul (September 1995). "A vision of the future". Amiga Computing. No. 90. IDG Media. pp. 48–50. ISSN 0959-9630. 
19. ↑ Thieullet, Cyrille (October 1995). "Comparatif des cartes graphiques, Cinq cartes sous la loupe". AmigaNews (in French). No. 83. NewsEdition. pp. 26–28. ISSN 1164-1746. 
20. ↑ Veitch, Nick (January 1999). "CyberGraphX 4". Amiga Format. No. 119. Future Publishing. p. 52. ISSN 0957-4867. 
21. 1 2 amiga.resource.cx - Amiga Hardware Database - Village Tronic Picasso II, read 2012-08-24
22. ↑ Picasso96 rtg software
23. ↑ Němec, Luboš (March 1997). "Picasso IV". Amiga Review (in Czech). No. 26. Atlantida Publishing. pp. 14–15. ISSN 1211-1465. 
24. ↑ Němec, Luboš (June 1997). "Picasso IV & Picasso96, blýská se na lepší časy?". Amiga Review (in Czech). No. 29. Atlantida Publishing. p. 9. ISSN 1211-1465. 
25. ↑ Zonias, Kymon (July 2004). "Pre-release AmigaOS 4.0". Amiga Future (in German). No. 49. APC&TCP. p. 37. 
26. ↑ Sutton, Mick; Williams, Robert (Winter 2004). "Amiga OS 4 Update" (PDF). No. 19. South Essex Amiga Link. p. 18. 
27. ↑ "AmigaOS 4.1 Hardware Compatibility List". Acube Systems. 2012-11-25. Retrieved 2014-05-08. 
28. ↑ "RadeonHD Version 1.0" (PDF) (Press release). Cardiff: A-EON Technology. 2014-03-27. Retrieved 2016-09-03. 
29. ↑ "RadeonHD Driver". Retrieved 2010-08-29.