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Streamlines

Commands of the streamlines chapter of the database, 12 entries. The status words are defined once, on the compatibility matrix, which says what each rests on and what the script builder does with it. Read it before this page: broken and removed are refusals, so a row here can be telling you the emitter will not write that command for that version.

DELETE_ALL_OFF_BODY_STREAMLINES

Phase analysis, layout bare. Manual: SRC-003 p.369.

Deletes every off-body streamline and streamtube. There is no command deleting one, so a seed placed wrongly costs the whole set.

Version Status Evidence
25.000 documented SRC-749 p.329, same grammar as 26.120
25.100 documented SRC-748 p.342, same grammar as 26.120
26.000 documented SRC-747 p.341, same grammar as 26.120
26.100 documented SRC-741 p.364, same grammar as 26.120
26.101 documented SRC-725 p.368, same grammar as 26.120
26.120 documented SRC-003 p.369
26.121 documented SRC-740 p.372, same grammar as 26.120
26.123 documented SRC-751 p.375, unchanged from SRC-750 p.375
26.124 documented SRC-752 p.375, the SRC-751 file, carried from 26.123; not run on 26.124

DELETE_ALL_SURFACE_STREAMLINES

Phase analysis, layout bare. Manual: SRC-003 p.370.

Deletes every on-body streamline.

Version Status Evidence
25.000 documented SRC-749 p.330, same grammar as 26.120
25.100 documented SRC-748 p.343, same grammar as 26.120
26.000 documented SRC-747 p.342, same grammar as 26.120
26.100 documented SRC-741 p.365, same grammar as 26.120
26.101 documented SRC-725 p.369, same grammar as 26.120
26.120 documented SRC-003 p.370
26.121 documented SRC-740 p.373, same grammar as 26.120
26.123 documented SRC-751 p.376, unchanged from SRC-750 p.376
26.124 documented SRC-752 p.376, the SRC-751 file, carried from 26.123; not run on 26.124

EXPORT_ALL_OFF_BODY_STREAMLINES

Phase export, layout param_lines. Manual: SRC-003 p.369.

Argument Specification
filename path
Version Status Evidence
25.000 documented SRC-749 p.329, same grammar as 26.120
25.100 documented SRC-748 p.342, same grammar as 26.120
26.000 documented SRC-747 p.341, same grammar as 26.120
26.100 documented SRC-741 p.364, same grammar as 26.120
26.101 documented SRC-725 p.368, same grammar as 26.120
26.120 verified reports/compat/CMP-26120_2026-08-08_full.yaml
26.121 verified reports/compat/CMP-26121_2026-08-08_full.yaml
26.122 verified reports/compat/CMP-26122_2026-08-11_full.yaml
26.123 verified reports/compat/CMP-26123_2026-08-17_full-sim.yaml; SRC-751 p.375, unchanged from SRC-750 p.375
26.124 verified reports/compat/CMP-26124_2026-09-14_full-sim.yaml; SRC-752 p.375, the SRC-751 file, carried from 26.123

EXPORT_ALL_SURFACE_STREAMLINES

Phase analysis, layout inline. Manual: SRC-003 p.370.

Writes every on-body streamline to one file, the path on the next line. The off-body counterpart is EXPORT_ALL_OFF_BODY_STREAMLINES, and the two write different things: friction lines here, fluid paths there.

Argument Specification
file path
Version Status Evidence
25.000 documented SRC-749 p.330, same grammar as 26.120
25.100 documented SRC-748 p.343, same grammar as 26.120
26.000 documented SRC-747 p.342, same grammar as 26.120
26.100 documented SRC-741 p.365, same grammar as 26.120
26.101 documented SRC-725 p.369, same grammar as 26.120
26.120 documented SRC-003 p.370
26.121 documented SRC-740 p.373, same grammar as 26.120
26.123 documented SRC-751 p.376, unchanged from SRC-750 p.376
26.124 documented SRC-752 p.376, the SRC-751 file, carried from 26.123; not run on 26.124

GENERATE_ALL_OFF_BODY_STREAMLINES

Phase analysis, layout bare. Manual: SRC-003 p.368.

Version Status Evidence
25.000 documented SRC-749 p.329, same grammar as 26.120
25.100 documented SRC-748 p.342, same grammar as 26.120
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 verified reports/compat/CMP-26120_2026-08-08_full.yaml
26.121 verified reports/compat/CMP-26121_2026-08-08_full.yaml
26.122 verified reports/compat/CMP-26122_2026-08-11_full.yaml
26.123 verified reports/compat/CMP-26123_2026-08-17_full-sim.yaml; SRC-751 p.374, unchanged from SRC-750 p.374
26.124 verified reports/compat/CMP-26124_2026-09-14_full-sim.yaml; SRC-752 p.374, the SRC-751 file, carried from 26.123

GENERATE_ALL_SURFACE_STREAMLINES

Phase analysis, layout bare. Manual: SRC-003 p.370.

Generates the on-body streamlines, which are surface friction lines rather than paths through the fluid: they follow the direction of the wall shear stress and are what a reader looks at to find separation lines and attachment lines. IT TAKES NOTHING, and that is the whole difference from the off-body family. The solver decides the seeding from the geometry, so there is nothing to place, size or aim.

Version Status Evidence
25.000 documented SRC-749 p.330, same grammar as 26.120
25.100 documented SRC-748 p.343, same grammar as 26.120
26.000 documented SRC-747 p.342, same grammar as 26.120
26.100 documented SRC-741 p.365, same grammar as 26.120
26.101 documented SRC-725 p.369, same grammar as 26.120
26.120 documented SRC-003 p.370
26.121 documented SRC-740 p.373, same grammar as 26.120
26.123 documented SRC-751 p.376, unchanged from SRC-750 p.376
26.124 documented SRC-752 p.376, the SRC-751 file, carried from 26.123; not run on 26.124

NEW_OFF_BODY_STREAMLINE

Phase analysis, layout keyword_block. Manual: SRC-003 p.368.

Argument Specification
position_x float
position_y float
position_z float
upstream enum in
Version Status Evidence
25.000 documented SRC-749 p.328, same grammar as 26.120
25.100 documented SRC-748 p.341, same grammar as 26.120
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 broken reports/compat/CMP-26120_2026-08-08_full.yaml; script processing aborted at the command: the log exported before it exists, the one after it never appeared (END sentinel missing)
26.121 broken reports/compat/CMP-26121_2026-08-08_full.yaml; script processing aborted at the command: the log exported before it exists, the one after it never appeared (END sentinel missing)
26.122 broken reports/compat/CMP-26122_2026-08-11_full.yaml; script processing aborted at the command: the log exported before it exists, the one after it never appeared (END sentinel missing)
26.123 broken reports/compat/CMP-26123_2026-08-17_full-sim.yaml; script processing aborted at the command: the log exported before it exists, the one after it never appeared (END sentinel missing)
26.124 broken reports/compat/CMP-26124_2026-09-14_full-sim.yaml; script processing aborted at the command: the log exported before it exists, the one after it never appeared (END sentinel missing)

NEW_OFF_BODY_STREAMTUBE

Phase analysis, layout inline. Manual: SRC-003 p.368.

Seeds a cylindrical bundle of off-body streamlines in one call, which is how a propeller or rotor slipstream is visualised without placing seeds individually. The two counts multiply: the number of streamlines created is RADIAL_STREAMLINES times CIRCULAR_STREAMLINES, and no edition says so. The manual describes the origin as being relative to the specified AXIS, which is not a frame; read with the FRAME_INDEX argument beside it, the position is in that coordinate system and the axis says which way the tube points. Recorded as the reading the two arguments together support, since neither alone would place a tube. THE TWO 25 EDITIONS WRITE THIS COMMAND AS A KEYWORD BLOCK and carry no row here because of it. They print KEY VALUE lines until a terminator, where 26.000 onward prints the arguments inline. A version row can override the argument grammar and cannot override the layout, so a row for those editions would emit the newer shape under an older build's citation, which is worse than refusing to emit at all. The reading exists and is withheld deliberately; the schema gap is PLN-20260810-1200.

Argument Specification
frame_index int
axis enum in
x float [simulation length units]
y float [simulation length units]
z float [simulation length units]
radius float [simulation length units]
radial_streamlines int
circular_streamlines int
Version Status Evidence
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 documented SRC-003 p.368
26.121 documented SRC-740 p.371, same grammar as 26.120
26.123 documented SRC-751 p.374, unchanged from SRC-750 p.374
26.124 documented SRC-752 p.374, the SRC-751 file, carried from 26.123; not run on 26.124

NEW_STREAMLINE_DISTRIBUTION

Phase analysis, layout keyword_block. Manual: SRC-003 p.368.

SUBDIVISIONS is N+1 for N streamlines between the start and end vertices.

Argument Specification
position_1_x float
position_1_y float
position_1_z float
position_2_x float
position_2_y float
position_2_z float
subdivisions int
Version Status Evidence
25.000 documented SRC-749 p.328, same grammar as 26.120
25.100 documented SRC-748 p.341, same grammar as 26.120
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 verified reports/compat/CMP-26120_2026-08-08_full.yaml
26.121 verified reports/compat/CMP-26121_2026-08-08_full.yaml
26.122 verified reports/compat/CMP-26122_2026-08-11_full.yaml
26.123 verified reports/compat/CMP-26123_2026-08-17_full-sim.yaml; SRC-751 p.374, unchanged from SRC-750 p.374
26.124 verified reports/compat/CMP-26124_2026-09-14_full-sim.yaml; SRC-752 p.374, the SRC-751 file, carried from 26.123

SET_ALL_OFF_BODY_STREAMLINES_DOWNSTREAM

Phase analysis, layout bare. Manual: SRC-003 p.368.

Propagates every off-body streamline with the flow. The pair with the command above, and neither states which is the default.

Version Status Evidence
25.000 documented SRC-749 p.329, same grammar as 26.120
25.100 documented SRC-748 p.342, same grammar as 26.120
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 documented SRC-003 p.368
26.121 documented SRC-740 p.371, same grammar as 26.120
26.123 documented SRC-751 p.374, unchanged from SRC-750 p.374
26.124 documented SRC-752 p.374, the SRC-751 file, carried from 26.123; not run on 26.124

SET_ALL_OFF_BODY_STREAMLINES_UPSTREAM

Phase analysis, layout bare. Manual: SRC-003 p.368.

Propagates every off-body streamline against the flow, back toward where its fluid came from. Applies to all of them at once; there is no per-streamline direction command.

Version Status Evidence
25.000 documented SRC-749 p.329, same grammar as 26.120
25.100 documented SRC-748 p.342, same grammar as 26.120
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 documented SRC-003 p.368
26.121 documented SRC-740 p.371, same grammar as 26.120
26.123 documented SRC-751 p.374, unchanged from SRC-750 p.374
26.124 documented SRC-752 p.374, the SRC-751 file, carried from 26.123; not run on 26.124

SET_OFF_BODY_STREAMLINE_LENGTH

Phase analysis, layout keyword_block. Manual: SRC-003 p.368.

How far a newly created off-body streamline is propagated: to a stated length, or until it leaves the domain. THE TWO KEYWORDS ARE ALTERNATIVES AND THE MANUAL SAYS SO IN ITS HEADING, which is why both are optional here rather than one being required. SET_UNRESTRICTED_LENGTH is a bare presence keyword taking no value, so it is typed bool: passing True writes the keyword line and False writes nothing. Nothing refuses both at once. The manual states the alternation and does not say what the solver does when given both, so a refusal here would be this database inventing a rule; the caller passes one. THE PAGE'S ONLY SAMPLE LINE IS COMMENTED OUT, printing the keyword behind a hash so that the sample as written sets nothing. Recorded as the alternation the table states, not as the sample runs.

Argument Specification
set_length float [simulation length units] (optional)
set_unrestricted_length bool (optional)
Version Status Evidence
25.000 documented SRC-749 p.328, same grammar as 26.120
25.100 documented SRC-748 p.341, same grammar as 26.120
26.000 documented SRC-747 p.340, same grammar as 26.120
26.100 documented SRC-741 p.363, same grammar as 26.120
26.101 documented SRC-725 p.367, same grammar as 26.120
26.120 documented SRC-003 p.368
26.121 documented SRC-740 p.371, same grammar as 26.120
26.123 documented SRC-751 p.374, unchanged from SRC-750 p.374
26.124 documented SRC-752 p.374, the SRC-751 file, carried from 26.123; not run on 26.124