Lingo bytecode - Revision history

System25 at 12:18, 8 April 2023

2023-04-08T12:18:41Z

Effect2: Added links, including one redlink (Lingo)

2020-10-09T08:30:55Z

Added links, including one redlink (Lingo)

System25 at 00:57, 4 January 2019

2019-01-04T00:57:56Z

Captainkirk: /* Three Byte Instructions */

2018-05-23T22:12:30Z

‎Three Byte Instructions

Captainkirk: /* Three Byte Instructions */

2018-05-23T22:12:06Z

‎Three Byte Instructions

Captainkirk: /* Two-Byte Instructions */

2017-09-08T20:53:56Z

‎Two-Byte Instructions

Captainkirk: /* Two-Byte Instructions */

2017-09-08T20:52:59Z

‎Two-Byte Instructions

Captainkirk: /* One-Byte Instructions */

2017-09-08T20:43:04Z

‎One-Byte Instructions

Captainkirk: /* Two-Byte Instructions */

2017-09-08T04:37:48Z

‎Two-Byte Instructions

Captainkirk: /* Two-Byte Instructions */

2017-09-08T04:36:00Z

‎Two-Byte Instructions

@@ Line 889: / Line 889: @@
 Pop [cast ID, property ID] and push the value of property for the given cast according to these property IDs:
 {| class="wikitable"
 |-
 ! 0F

@@ Line 21: / Line 21: @@
 }}
-This is a partial, work-in-progress examination of the bytecode created when Lingo code is compiled in Macromedia Director 4.0. It describes instructions for a stack-based virtual machine. This virtual machine is sometimes known as the IML, or Idealized Machine Layer.
+This is a partial, work-in-progress examination of the bytecode created when [[Lingo]] code is compiled in [[Shockwave (Director)|Macromedia Director]] 4.0. It describes instructions for a stack-based virtual machine. This virtual machine is sometimes known as the IML, or Idealized Machine Layer.
 Each instruction is one, two or three bytes.
@@ Line 1,379: / Line 1,379: @@
 == Lingo script decompile ==
-A proof of concept of a Lingo script decompiler (still a Work In Progress) can be found in "drxtract" python script (DRI and DRX files data extractor) in GitHub (https://github.com/System25/drxtract).
+A proof of concept of a Lingo script decompiler (still a Work In Progress) can be found in "drxtract" [[python]] script (DRI and DRX files data extractor) in GitHub (https://github.com/System25/drxtract).
-This scripts tries to extract images as BMP files, sound as WAV files and Lingo scripts as Lscr files.
+This scripts tries to extract images as [[BMP]] files, sound as [[WAV]] files and Lingo scripts as Lscr files.
 The relationship between the file names and the cast members must be calculated with the help of the KEY file and CAS file.

@@ Line 324: / Line 324: @@
+|
 | +1
-| Push a constant from local constant records onto the stack. These records seem to be six bytes long (regardless of the actual size of the constant value), so pushing the first one is <code>44 00</code>, the second is <code>44 06</code>, the third is <code>44 0C</code>, etc. To push the 65th one and beyond use code <code>84 YY ZZ</code>
+| Push a constant from local constant records onto the stack. These records seem to be six (or 8) bytes long (regardless of the actual size of the constant value), so pushing the first one is <code>44 00</code>, the second is <code>44 06</code> (or 44 08), the third is <code>44 0C</code>, etc. To push the 65th one and beyond use code <code>84 YY ZZ</code>
 |-
 ! 45&nbsp;XX
@@ Line 363: / Line 363: @@
+|
 | +1
-| Push the value of a function call parameter. The parameter records seem to be 6 bytes long, so the first is pushed with 4B 00, the second with 4B 06, etc.
+| Push the value of a function call parameter. The parameter records seem to be 6 (or 8) bytes long, so the first is pushed with 4B 00, the second with 4B 06 (or 4B 08), etc.
 |-
 ! 4C&nbsp;XX
@@ Line 369: / Line 369: @@
+|
 | +1
-| Push the value of a local variable. The local variable records seem to be 6 bytes long, so the first is pushed with <code>4C 00</code>, the second with <code>4C 06</code>, etc.
+| Push the value of a local variable. The local variable records seem to be 6 (or 8) bytes long, so the first is pushed with <code>4C 00</code>, the second with <code>4C 06</code> (or 4C 08), etc.
 |-
 ! 4D&nbsp;XX
@@ Line 431: / Line 431: @@
 |-
 ! 59&nbsp;16
-| <code>put&nbsp;"extra" into&nbsp;textVar</code>
+| <code>put&nbsp;value into&nbsp;field&nbsp;textVar</code>
-| -1
+| -3
+|
-| (Not sure how the target value is specified, needs more research)
+| Pops 0, the variable name and the value from the stack and sets the value of the variable. The 0 is supposed to be related with the "field" mark. More investigation needed.
 |-
 ! 59&nbsp;25
-| <code>put&nbsp;"extra" after&nbsp;textVar</code>
+| <code>put&nbsp;value after&nbsp;textVar</code>
-| -1
+| -2
+|
-| (See above)
+| Pops variable name and value from the stack and adds the value after the current value of the variable (string concatenation).
 |-
 ! 59&nbsp;35
-| <code>put&nbsp;"extra" before&nbsp;textVar</code>
+| <code>put&nbsp;value before&nbsp;textVar</code>
-| -1
+| -2
+|
-| (See above)
+| Pops variable name and value from the stack and adds the value before the current value of the variable (string concatenation).
 |-
 ! 5A&nbsp;XX
@@ Line 454: / Line 454: @@
 | XX determines the operation (0x1- = insert, 0x2- = after, 0x3-= before ) and the object type (0x-5 = local, 0x-4 = parameter, 0x-2 = object, 0x-6 = global). Both local and parameter are passed in as numbers and need to be looked up. Still need to do more work to map all XX codes. codes 59 XX, and 5B XX probably work the same.
 |-
-! 5B&nbsp;02
+! 5B&nbsp;XX
-| <code>delete&nbsp;item&nbsp;3 of&nbsp;textVar</code>
+| <code>delete&nbsp;something&nbsp;3 of&nbsp;textVar</code>
-| -9
-−
-| Like code <code>17</code>, except deletes specific item.
-|-
-! 5B&nbsp;05
-| <code>delete&nbsp;word&nbsp;3 of&nbsp;textVar</code>
-| -1
-−
-| (See above)
-|-
-! 5B&nbsp;06
-| <code>delete&nbsp;line&nbsp;3 of&nbsp;textVar</code>
 | -9
+|
-| Like code <code>17</code>, except deletes specific line.
+| Like code <code>17</code>, except deletes specific item, word, line or character.
 |-
 ! 5C&nbsp;00
@@ Line 1,344: / Line 1,332: @@
 Each constant record is six bytes long and has this format:
 * uint16: Value type ID
 * uint32: Data address, relative to the base address given in the header
@@ Line 1,384: / Line 1,376: @@
 * The file address of the main RIFF data file
 * Six further addresses for other embedded data (more research required to know more about these)
 [[Category:Development]]

@@ Line 1,126: / Line 1,126: @@
 ! a6&nbsp;XX&nbsp;YY
+|
-<code>localfunction(1,2,3)</code>
+<code>the shiftDown</code>
 | - 1
 | +1 or 0

@@ Line 1,129: / Line 1,129: @@
 | - 1
 | +1 or 0
-| Like code <code>56 XX</code>, except for use with larger index: (XX * 0x100) + YY.
+| Like code <code>66 XX</code>, except for use with larger index: (XX * 0x100) + YY.
 |}

@@ Line 449: / Line 449: @@
 |-
 ! 5A&nbsp;XX
-| <code>put &nbsp;value (chunkexpression)</code>
+| <code>put&nbsp;value&nbsp;(chunkexpression)</code>
 | -10
+|
-| Like code 59, XX determines the operation (0x1- = insert, 0x2- = after, 0x3-= before ) and the object type (0x-5 = local, 0x-4 = parameter, 0x-2 = object, 0x-6 = global). Both local and parameter are passed in as numbers and need to be looked up. Still need to do more work to map all XX codes. codes 59 XX, and 5B XX probably work the same.
+| XX determines the operation (0x1- = insert, 0x2- = after, 0x3-= before ) and the object type (0x-5 = local, 0x-4 = parameter, 0x-2 = object, 0x-6 = global). Both local and parameter are passed in as numbers and need to be looked up. Still need to do more work to map all XX codes. codes 59 XX, and 5B XX probably work the same.
 |-
 ! 5B&nbsp;02

@@ Line 212: / Line 212: @@
 | The string to slice
 |}
-The positions used here are one-based, so zero is invalid as a position and is instead used to indicate unused parameters. Only one "first X position" can be set, the rest must be zero. The corresponding "last X position" may either be set too, or it can be zero, in which case the first position will also be used as the last.
+The positions used here are one-based, so zero is invalid as a position and is instead used to indicate unused parameters. <strike>Only one "first X position" can be set, the rest must be zero.</strike>. Multiple first positions can be set to form constructs like "first character of the second word", or "first word of the second line". The corresponding "last X position" may either be set too, or it can be zero, in which case the first position will also be used as the last.
 |-
 ! 18

@@ Line 900: / Line 900: @@
 ! 0F
 | <code>directToStage</code>
 |-
 ! 10
 | <code>sound</code>
 |-
 ! 5D&nbsp;00