View source for Sierra Creative Interpreter

{{TechStub}}
<div align="center" style="font-size: 22pt">Sierra Creative Interpreter (SCI)</div><br />
<div class="FloatRight"></div>
{{EngineInfobox
| EngineName = SCI
| Image = <!-- [[Image:SCILogo.png|190px]]<br />
''SCI Logo'' -->
| DatesUsed = [[1988]] - [[1996]]
| Company = {{SierraOnLineEng}}
| Developer = {{JeffStephensonEng}}
| EngType =  {{AdvenEng}}, {{GraphicalParserEng}} ([[SCI0]]), {{PointNClickEng}}
| DevLang = {{C++}}
| OpenSource = {{ClosedEng}}
| Source = {{SourceEng}}
| License = {{NoLicense}}
| Platform = {{DOSEng}}, {{WinEng}}, {{AppleIIEng}}, {{AppleIIgsEng}}, {{AmigaEng}}, {{AtariSTEng}}, {{FMTownsEng}}
| Website = {{SierraURL}}
}}

<br />
==<br /><br /> Description ==

<blockquote>
The  '''SC'''ript '''I'''nterpreter or later, '''S'''ierra '''C'''reative '''I'''nterpreter, (SCI), or as it later became known as, '''S'''ierra '''C'''reative '''I'''nterpreter, is the [[w:scripting language|scripting language]] created by [[Jeff Stephenson]] for [[Sierra On-Line]], which was used between the years of 1989 to 1997. It superseded Sierra's earlier interpreter or engine, [[AGI|AGI]], and the [[w:runtime environment|runtime environment]] for such adventure games. SCI was used to create such games as ''[[King's Quest IV: The Perils of Rosella|King's Quest IV]]'' to VII, ''[[Space Quest III]]'' to ''[[Space Quest 6|6]]'', ''[[Quest for Glory I]]'' to ''[[Quest for Glory IV: Shadows of Darkness|IV]]'' and ''[[Gabriel Knight: Sins of the Fathers|Gabriel Knight I]]'' and ''[[Beast Within: A Gabriel Knight Mystery|II]]'', and the [[w:runtime environment|runtime environment]] for these games. Although ports for the [[Amiga]], [[Atari ST]], [[Macintosh]] and [[PC-98|PC-9801]] platforms exist, the primary development was for [[MS-DOS]] and [[Windows]] on the [[w:IBM PC|IBM PC]] platform.
</blockquote>

==<br /> Design ==

<blockquote>
While [[AGI]] was a [[w:Procedural programming|procedural]] language, SCI is completely [[w:Object-oriented programming|object-oriented]]. For more detailed information, see the [[SCI Specifications]].
</blockquote>

==<br /> Specifications ==

<blockquote>
<!-- Specifications here -->
</blockquote>

==<br /> Versions ==
<blockquote>
Although continuously developed between 1988 and 1996, five major versions can be isolated:

=== SCI0 ===

'''S'''ierra '''C'''reative '''I'''nterpreter v0.000.xxx<br />
First used for ''[[King's Quest IV: The Perils of Rosella]]'' in 1988, ''SCI0'' (0.000.xxx) allowed for 16 color 320×200 graphics as well as a music-card compatible soundtrack. It also supported parser-based keyboard input which a game could be scripted to use if it wishes to do so (non-adventure games usually didn't). Used from 1988 to 1990.

;Features:
* Video: 320x200 resolution
* Palette: 16 colors (plus dithering)
* Audio: MIDI
* Input: Text parser
* Platform(s): IBM PC (including PCjr & TANDY), Commodore AMIGA, Atari ST & Apple Macintosh

[[Sierra SCI Release List#SCI0|Games using SCI0]]

<blockquote>
==== SCI0 Resources ====

The resource types of SCI0 can be roughly grouped into four sets:

* <div id="VIEW"></div>'''[[VIEW Resource (SCI)|VIEW]]''' - [[SCI_Specifications: Chapter 1 - Introduction#SCI0 Graphical resources summarized|Graphics]]
* <div id="PIC"></div>'''[[Picture Resource (SCI)|PIC]]''' - [[SCI_Specifications: Chapter 1 - Introduction#SCI0 Graphical resources summarized|Graphics]]
* <div id="SCRIPT"></div>'''[[Script Resource (SCI)|SCRIPT]]''' - [[SCI Specifications: Chapter 1 - Introduction#SCI0 Logic resources summarized|Logic]]
* <div id="TEXT"></div>'''[[Text Resource (SCI)|TEXT]]''' - <!-- [[Strings]] --> (Text resources are series of ASCII strings)
* <div id="SOUND"></div>'''[[Sound Resource (SCI)|SOUND]]''' - [[SCI Specifications: Chapter 1 - Introduction#SCI0 Sound resources summarized|Sound]]
* <div id="VOCAB"></div>'''[[VOCAB Resource (SCI)|VOCAB]]''' - [[SCI Specifications: Chapter 1 - Introduction#SCI0 Logic resources summarized|Logic]]
* <div id="FONT"></div>'''[[Font Resource (SCI)|FONT]]''' - [[SCI_Specifications: Chapter 1 - Introduction#SCI0 Graphical resources summarized|Graphics]]
* <div id="CURSOR"></div>'''[[CURSOR Resource (SCI)|CURSOR]]''' - [[SCI_Specifications: Chapter 1 - Introduction#SCI0 Graphical resources summarized|Graphics]]
* <div id="PATCH"></div>'''[[Patch Resource (SCI)|PATCH]]''' - [[SCI Specifications: Chapter 1 - Introduction#SCI0 Sound resources summarized|Sound]]
<!--; the other resources deserve further discussion.-->
</blockquote>

=== SCI0.1 ===

Quest for Glory II has been falsely identified by some as SCI1, but is actually SCI01. Perhaps this is because its debug reports SCI version 1.000.*** even when the interpreter itself is 0.001.0**. Used from 1989 to 1991.

;Features:
* 

<!-- <div class="Quote">
{{Quote|Attrib = {{CoreyColeQ}}
}}
"Quest for Glory II definitely did *not* use the SCI1 interpreter that Sierra used for King's Quest V and the other 256-color EGA games. That interpreter did not have a parser, so could not handle typed input at all. If they internally called QfG2's interpreter 'SCI1', it was just a PR thing - It was not the same interpreter.

"As to *why* QfG2 used the parser and EGA graphics, it's because all of Sierra's other games were running late. Sierra needed a major release for Christmas 1990, and we were the sacrificial lamb. (I think it was partially because I did not fight as hard as Mark Crowe - The choice was between QfG2 and SQ3 as to which game would ship early, but with 16-color graphics.)"
</div>
 -->

[[Sierra SCI Release List#SCI0.1|Games that use SCI0.1]]

<blockquote>
==== SCI0.1 Extensions ====

SCI01 differs only in very few respects: It uses different compression algorithms and a different type of sound resources, which may contain digitized sound effects (PCM data). The basic music data, however, still resembles MIDI data.

Also, scripts are split into two parts when loaded: A dynamic part, which resides in the heap as before, and a static part, which is stored externally to conserve heap space.<ref>The background for this is that heap space started running out in Quest for Glory 2. In order to compensate for this, changes were made to both the script library and the interpreter.</ref>
</blockquote>

=== SCI1 ===

''S''ierra's ''C''reative ''I''nterpreter v1.000.xxx<br />
Released in 1990, the most notable improvement in ''SCI1'' (1.000.xxx/T.A00.xxx) was the support of 256 color graphics, still at a resolution of 320×200; EGA 16 color graphics were still available (games were usually sold in separate 16 and 256 color versions). Some people prefer to call the 16-color SCI1 interpreters "SCI01". With the shift to SCI1, Sierra began using a digitized painting process for background artwork, rather than the pixel-by-pixel process of previous engines: the difference is readily apparent if one compares, for example, ''[[King's Quest IV: The Perils of Rosella|King's Quest 4]]'' against ''[[King's Quest V: Absence Makes the Heart Go Yonder|King's Quest 5]]''. SCI1 also introduced a Point&Click interface (a mouse-driven, icon-based), which was implemented by the game's scripts instead of the SCI1 interpreter. This is also how Shane Cloud (Cloudee1) of [[scip:|SCI Programming]] created a Point&Click interface to the SCI0 template game for SCI Studio and SCI Companion 3.<!-- 

Most SCI1 games are completely mouse-driven, using an icon-based interface; contrary to popular thought, it is up to the game's script code, not to the interpreter, to implement the user interface. For example, even though ''[[Quest for Glory II: Trial by Fire|Quest for Glory 2]]'' is parser-driven and ''[[King's Quest V: Absence Makes the Heart Go Yonder|King's Quest 5]]'' is mouse-driven, they use compatible interpreters, as it is possible to use the interpreter from QFG2 with the EGA version of KQ5. --> 

The version numbering scheme is somewhat confusing for the reason that the third number in the version string (the build number) has only three digits, even though four are needed. For example, the game ''Space Quest 4'' Version 1.052 ships with an interpreter labeled "1.000.753", whereas the game ''[[Conquests of the Longbow]]'' Version 1.0 ships with an interpreter labeled "1.000.168"; nevertheless, the latter interpreter is newer because the build number is actually 1168, not 168. Also, in some cases the "1.000" is replaced with "T.A00", which however does not indicate a separate development fork. Used from 1990 to 1993.

;Features:
* Video: 320x200 resolution
* Palette: 256 colors (32 colors on the Amiga)
* Audio: MIDI/Digital audio
* Platforms: IBM PC (286+), Commodore AMIGA, Apple Macintosh & FM Towns(?)

[[Sierra SCI Release List#SCI1|Games that use SCI1]]

<blockquote>
==== SCI1 Extensions ====

SCI1 introduced new concepts like Palettes, scaled bitmap images and several new compression algorithms. In SCI1.0, the resource limit was first increased to 16383<ref>This appears to be the limit- none of the SCI1.0 games tested used resource numbers beyond 16383</ref>, and then to 65535 in SCI1. Because of the inherent limitations of the FAT file system the primary target OS of Sierra's SCI interpreter was limited to, patch file names were altered accordingly, with the resource number (not padded) before the dot and a three-letter resource ID behind it; examples are "0.scr" or "100.v56".

The complete list of suffixes is as follows:
* <div id="V56"></div>80: '''[[V56]]''': 256 color views
* <div id="P56"></div>81: '''[[Picture Resource (SCI)#P56|P56]]''': 256 color background pictures
* <div id="SCR"></div>82: '''[[Script Resource (SCI)#SCR|SCR]]''': Scripts (static data)<ref name="ResourceSplit">The script resource split introduced in SCI01 was incorporated into the actual resource layout in SCI1.<sup>[[:Category:Pages Requiring Citation|Requires Citation]]</sup>[[Category:Pages Requiring Citation]]</ref>
* <div id="TEX"></div>83: '''[[Text Resource (SCI)#TEX|TEX]]''': Texts (deprecated in favor of messages)
* <div id="SND"></div>84: '''[[Sound Resource (SCI)#SND|SND]]''': Sound data (MIDI music)
* 85: No extension: Type 0x85 resources are 'memory' resources, which are only used internally.
* <div id="VOC"></div>86: '''[[VOCAB Resource (SCI)#VOC|VOC]]''': Vocabulary (not used)
* <div id="FON"></div>87: '''[[Font Resource (SCI)#FON|FON]]''': Fonts
* <div id="CUR"></div>88: '''[[CURSOR Resource (SCI)#CUR|CUR]]''': Mouse cursors (deprecated in favor of v56-based cursors)
* <div id="PAT"></div>89: '''[[Patch Resource (SCI)#PAT|PAT]]''': Audio patch files
* <div id="BIT"></div>8a: '''[[BIT]]''': Bitmap files (purpose unknown)
* <div id="PAL"></div>8b: '''[[Palette Resource (SCI)#PAL|PAL]]''': 256 color palette files
* <div id="CDA"></div>8c: '''[[CDA]]''': CD Audio resources
* <div id="AUD"></div>8d: '''[[Audio Resource (SCI)#AUD|AUD]]''': Audio resources (voice and digital sound effects)
* <div id="SYN"></div>8e: '''[[Sync Resource (SCI)#SYN|SYN]]''': Sync (purpose unknown)
* <div id="MSG"></div>8f: '''[[Message Resource (SCI)#MSG|MSG]]''': Message resources: Text plus metadata
* <div id="MAP"></div>90: '''[[Resource MAP File (SCI)#MAP|MAP]]''': Maps location of resources for interpreter
* <div id="HEP"></div>91: '''[[HEAP Resource (SCI)#HEP|HEP]]''': Heap resources: Dynamic script data<ref name="ResourceSplit" />
* <div id="SEQ"></div>??: '''[[SEQ Resource (SCI)#SEQ|SEQ]]''': Sequence resources for cut scenes
</blockquote>

=== SCI1.1 ===

Apart from considerable internal changes, ''SCI1.1'' (1.001.xxx) added support for animated movie sequences (first used in KQ6) as well as scaling sprites: characters would become smaller as they walk into the distance, giving a pseudo-3D effect. (The interpreters from some early SCI1.1 games bear a "2.000.000" version stamp; this is most likely an inconsistency which should be ignored.)

Separate 16-color packages were no longer available; EGA owners instead would be presented a 640×200 graphics display that simulated 256 colors via dithering.  Used from 1990 to 1993.

;Features:
* Video: 320x200 resolution
* Palette: 256 colors (32 colors on the Amiga)
* Audio: MIDI/Digital audio
* Platforms: IBM PC (286+), Commodore AMIGA, Apple Macintosh & FM Towns(?)

[[Sierra SCI Release List#SCI1.1|Games that use SCI1.1]]

<blockquote>
==== SCI11 Extensions ====

* <div id="Audio36"></div> '''[[Audio Resource (SCI)#Audio36|Audio36]]''': Audio36 resources
* <div id="Sync36"></div> '''[[Sync Resource (SCI)#Sync36|Sync36]]''': Sync36 resources
</blockquote>

=== SCI 32 ===

Often called ''SCI32'' (along with ''SCI3''), ''SCI2'' (2.xxx.xxx) runs in 32-bit mode by using the ''[[w:DOS/4G|DOS/4GW]]'' extender or by running it in Windows 3.1's Win32s. Most notable is the support of high-resolution 640×480 graphics, as well as better movie support. Used from 

;Features:
* 

==== SCI2 ====

There are two known revisions, 2.000.000, and 2.100.002. 

[[Sierra SCI Release List#SCI2|Games that use SCI2]]

<blockquote>
===== SCI2 Extensions =====

Used from 

* <div id="WAV"></div> '''[[WAV]]''': PCM audio resources (external)

;Features:
* 
</blockquote>

====<br /> SCI21 ====

&nbsp;<!-- Add SCI21 description here -->

[[Sierra SCI Release List#SCI2.1|Games that use SCI21]]

<blockquote>
===== SCI21 Extensions =====

Early versions used a modified SCI2 kernel table. Most of these games maintain the "old school" Sierra graphics. Robot videos were introduced, in the DOS version of KQ7.
<div id="VMD"></div>
<div id="RBT"></div>Middle versions include the finalized kernel function table, the addition of '''VMD''' video resource and a more heavy usage of '''RBT''' (robot) videos. Graphics in these games were generally either cartoonish or 3D pre-rendered from filmed actors. Used from 

* <div id="Robot"></div> '''[[RBT]]''': RBT (robot) video resources (external)
* <div id="VMD"></div> '''[[VMD]]''': VMD video resources (external)

;Features:
* 
</blockquote>

==== SCI3 ====

A.K.A. "SCI32" The last version, ''SCI32'' (3.000.000) could not only run under DOS or Windows 3.1, but also natively under Windows 95.  Used from 

;Features:
* 

[[Sierra SCI Release List#SCI3|Games that use SCI3]]

<blockquote>
===== SCI3 Extensions =====

Middle versions include the finalized kernel function table (which was also used in the SCI3 games)
</blockquote>
</blockquote>

==<br /> Non-SCI ==

Some Sierra games used SCI resources, such as graphics and sounds, but did not use the SCI script interpreter itself. Games include:

*''[[Shivers Two: Harvest of Souls]]''

==<br /> Related software ==

<blockquote>
SCI editors can be used to uncover unfinished game elements that had been concealed in the game's resource files by the developer during the game's development. These hidden resources include unfinished artworks, puzzles, scenery, voiceover or music recordings as well as gags inserted by the development team. <ref>Beebe, Jess (2008-08-18) [http://www.adventureclassicgaming.com/index.php/site/features/374/ "Resource Quest: hidden treasures in Sierra’s adventure games"] Adventure Classing Gaming Retrieved 2008-09-14</ref> Examples of game titles from which such hidden resources have been uncovered include ''[[King's Quest V: Absence Makes the Heart Go Yonder]]'' (SCI1.1), ''[[Space Quest IV: Roger Wilco and the Time Rippers]]'' (SCI1.1), ''[[Leisure Suit Larry 6: Shape Up or Slip Out!]]'' (SCI1.1), ''[[King's Quest VII: The Princeless Bride]]'' (SCI2), and ''[[Space Quest 6: The Spinal Frontier]]'' (SCI2).

===<br /> In-house Tool Screenshots ===

{| align="center" width="80%"
|-
| align="center"|[[Image:PESCI.png|320px]]|| align="center"|[[Image:ViewEdit.png|320px]]
|-
| align="center"| SCI0 Picture Editor<br />with the mansion from [[The Colonel's Bequest]]<br />&nbsp;
| align="center"| SCI View Editor<br />with the statue in front of the mansion from [[The Colonel's Bequest]]<br />&nbsp;
|}

{| align="center" width="80%"
|-
| align="center"| <!-- [[Image:.png|320px]] --> || align="center"| [[Image:DouglasHerringsDesk.png|320px]]
|-
| align="center"| &nbsp; || align="center"| SCI View Editor on [[Douglas Herring|Douglas Herring's]] Desk
|}
</blockquote>

==<br /> References ==

<references/>

==<br /> See Also ==

* [[SCI Specifications|FreeSCI's SCI Specifications]]
* [[Sierra SCI Release List|List of the Sierra SCI games]]
* [[:Category:Releases Developed with SCI|Releases Developed with SCI (category)]]
* [[SCI Specifications|Sierra Creative Interpreter Specifications]]
* [[:Category:SCI Resources|SCI Resources]]
* [[Adventure Game Interpreter|Adventure Game Interpreter]]

==<br /> External Links ==

* [http://www.scriptinterpreter.com/home Lance Ewing's SCript Interpreter]
<!-- * [[w:Sierra's Creative Interpreter|SCI on Wikipedia]] -->
* [http://web.archive.org/web/20110724131221/http://www.welovedosgames.net/article.php?article=The%20success%20of%20Sierras%20Creative%20Interpreter%20%28SCI%29 The success of Sierra's Creative Interpreter (SCI)] (web archive)
* [http://web.archive.org/web/20090221115724/http://freesci.linuxgames.com/ FreeSCI homepage] (web archive)
* [[scip:|The SCI Programming Community]]
* [http://scistudio.sourceforge.net/ SCI Studio: The Complete SCI Game Development System]
* [http://web.archive.org/web/20091012094351/http://agisci.classicgaming.gamespy.com/ The Ultimate AGI & SCI Web Site] (web archive)
<!-- * [[w:Sierra's_Creative_Interpreter|SCI on Wikipedia]] -->
* [http://www.dmoz.org/Games/Video_Games/Adventure/Graphical_Adventures/Design_and_Development/Authoring_Systems/Sierra/SCI/ Sierra's Creative Interpreter] on the [[w:Open Directory Project]]
* [[shp:Patches-Updates/NewSierraInstallers.html|Modern installers for the Sierra AGI and SCI games]]
* [http://www.squirtthecat.com/ Updates to run SCI3 based games on XP/Vista]
* [[mobygrp:game-engine-sierras-creative-interpreter-sci|SCI on MobyGames]]

&nbsp;

<!--[[Category:Game Development Software]]-->
<!--[[Category:Adventure Game Engines]]-->
[[Category:Technical Info]]
[[Category:Development]]