@@ -2443,9 +2443,9 @@ OR supports the following special visual effects in a steam locomotive:
24432443
24442444OR supports the following special visual effects in a diesel locomotive:
24452445
2446- - Exhaust (named ``Exhaustnumber ``) -- is a diesel exhaust. Multiple exhausts can
2447- be defined, simply by adjusting the numerical value of the number after the key
2448- word exhaust .
2446+ - Exhaust (named ``Exhaustnumber ``, eg: `` Exhaust2 `` ) -- is a diesel exhaust. Multiple
2447+ exhausts can be defined, simply by adjusting the numerical value of the number after
2448+ the key word Exhaust .
24492449
24502450OR supports the following special visual effects in a wagon (also the wagon section of
24512451an ENG file):
@@ -2474,16 +2474,16 @@ Each effect is defined by inserting a code block into the ENG/WAG file similar t
24742474the one shown below::
24752475
24762476 Cylinders11FX (
2477- -1.0485 1.0 2.8
2478- -1 0 0
2479- 0.1
2477+ Comment ( Required parameters. )
2478+ ORTSPosition ( -1.0485m 1.0m 2.8m )
2479+ ORTSInitialVelocity ( -1 0 0 )
2480+ ORTSParticleDiameter ( 0.1m )
24802481
2481- Comment ( ORTS parameters come after MSTS data! )
2482+ Comment ( Optional parameters. )
24822483 ORTSPositionVariation ( 0m 0m 0m )
2483- ORTSInitialVelocityVariation ( 0.1 0.1 0.1 )
2484- ORTSEmissionSpeedLimit ( 150m/s )
2484+ ORTSInitialVelocityVariation ( 0.1 )
24852485 ORTSFinalVelocity ( 0 1m/s 0 )
2486- ORTSFinalVelocityVariation ( 0.75m/s 0.75m/s 0.75m/s )
2486+ ORTSFinalVelocityVariation ( 0.75m/s )
24872487
24882488 ORTSLifespanMultiplier ( 1.0 )
24892489 ORTSLifespanVariation ( 0.5 )
@@ -2495,24 +2495,22 @@ the one shown below::
24952495 ORTSRotationVariation ( 0.25 )
24962496 ORTSWindMultiplier ( 1.0 )
24972497
2498+ ORTSParticleOpacity ( 1.0 )
24982499 ORTSPipeArea ( 0.03m^2 )
2499- ORTSMaxParticles ( 2500 )
25002500 ORTSRateMultiplier ( 1.0 )
25012501 ORTSUseChaoticRandomization ( false )
2502-
2502+
2503+ Comment ( Advanced optional parameters. )
2504+ ORTSMaxParticles ( 2500 )
2505+ ORTSEmissionSpeedLimit ( 150m/s )
25032506 ORTSGraphic ( "smokemain.ace" )
25042507 ORTSGraphicAtlasLayout ( 4 4 )
25052508 )
25062509
2507- The code block consists of the following elements:
2508-
2509- - Effect name -- as described above,
2510- - Effect location on the locomotive (given as an x, y, z offset in metres
2511- from the origin of the wagon shape)
2512- - Effect direction of emission (given as a normal x, y and z)
2513- - Effect nozzle width (in metres)
2514-
25152510.. index ::
2511+ single: ORTSPosition
2512+ single: ORTSInitialVelocity
2513+ single: ORTSParticleDiameter
25162514 single: ORTSPositionVariation
25172515 single: ORTSInitialVelocityVariation
25182516 single: ORTSEmissionSpeedLimit
@@ -2530,42 +2528,51 @@ The code block consists of the following elements:
25302528 single: ORTSMaxParticles
25312529 single: ORTSRateMultiplier
25322530 single: ORTSUseChaoticRandomization
2531+ single: ORTSParticleOpacity
25332532 single: ORTSGraphic
25342533 single: ORTSGraphicAtlasLayout
25352534
2536- After including these settings, additional *optional * parameters unique to OR can
2537- be included to further customize effect emitters:
2535+ While there are many parameters available to customize the appearance and behavior of emitted particles, most are set
2536+ to reasonable values by default and should be considered optional unless further customization is desired. The only
2537+ *required * parameters are as follows:
2538+
2539+ - ``ORTSPosition ( x y z ) `` -- REQUIRED parameter which defines the (+/-) right/left, up/down,
2540+ forward/backward location of the emitter (in meters by default, other units are accepted)
2541+ - ``ORTSInitialVelocity ( x y z ) `` -- REQUIRED to define the (+/-) right/left, up/down, forward/backward
2542+ components of emission direction (no units of measure, the particle speed is multiplied by
2543+ this vector to determine the 3D velocity of particles. Speed can be divided by inserting values
2544+ less than 1, or multiplied by inserting values greater than 1.)
2545+ - And ``ORTSParticleDiameter ( d ) `` -- REQUIRED to set the nozzle width (default units meters, other units accepted),
2546+ which sets the initial size of each particle
2547+
2548+ The *optional * parameters unique to OR are as follows:
25382549
25392550- ``ORTSPositionVariation ( x y z ) `` -- Specifies the amplitude of random variation
25402551 in the right/left, up/down, and front/back emission location of a particle (default units
25412552 are meters). Useful for non-circular exhaust ports, as it allows one particle emitter
25422553 to be used to spawn particles from an area, rather than a single point. Note that
2543- ``ORTSPositionVariation ( x y z ) `` would allow particles to emit 1 meter right and
2554+ ``ORTSPositionVariation ( 1 0 0 ) `` would allow particles to emit 1 meter right and
25442555 1 meter left of the initial position, for a total variation of 2 meters. Similar is
25452556 true of all other parameters related to randomness, the total variation is double what's
25462557 specified. Feature is disabled by default.
2547- - ``ORTSInitialVelocityVariation ( x y z ) `` -- Defines the randomization of initial particle
2548- velocity in the right/left, up/down, and front/back directions, as a function of the
2549- particle's initial speed (values are unitless). The default value is ( 0.1 0.1 0.1 ),
2550- meaning the speed in each direction can be increased or decreased by 10% of the initial
2551- particle speed. Larger values make the particle exhaust seem less directed and more diffuse.
2552- - ``ORTSEmissionSpeedLimit ( v ) `` -- Some particle emitters are driven by the simulated flow
2553- rate of exhaust, which has to make some assumptions about the pressure and volume of exhaust.
2554- This can lead to unrealistically high speed particles being emitted, so a speed limit can be
2555- set (default units are meters per second) to keep particle speed reasonable. This is not a hard
2556- limit, it is gradually enforced as the simulation calculates higher and higher exhaust speed.
2557- The limit is also applied before considering the emitter velocity factor, so actual exhaust speed
2558- will vary depending on other settings.
2559- By default, the limit is 150 meters per second, which will be suitable in most cases.
2558+ - ``ORTSInitialVelocityVariation ( i ) `` -- Defines the randomization of initial particle
2559+ velocity in all directions, multiplied by the particle's initial speed (no units of measure).
2560+ The default value is ( 0.1 ), meaning the speed in each direction can be increased or
2561+ decreased by 10% of the initial particle speed. Larger values make the particle exhaust seem
2562+ less directed and more diffuse. Alternately, 3 values can be provided in the format
2563+ ``ORTSInitialVelocityVariation ( x y z ) `` to specify the initial velocity variation in each
2564+ individual direction.
25602565- ``ORTSFinalVelocity ( x y z ) `` -- Determines the final right/left, up/down, and front/back
25612566 velocity of particles after they have settled (default units of meters per second). The default
25622567 is 1 m/s directly upward, and can be changed to fine tune the appearance of the particle trail
25632568 produced. Note that wind velocity is added to this value afterward.
2564- - ``ORTSFinalVelocityVariation ( x y z ) `` -- Unlike initial velocity variation, final velocity
2569+ - ``ORTSFinalVelocityVariation ( f ) `` -- Unlike initial velocity variation, final velocity
25652570 variation determines the amplitude of random variation of final velocity in absolute terms
25662571 (default units of meters per second). The default setting is +/- 0.75 m/s in all directions, but
25672572 changing this can adjust the amount of and shape of particle trail spread. Larger variations
2568- make for exhaust that seems more chaotic and diffuse.
2573+ make for exhaust that seems more chaotic and diffuse. Similar to initial velocity variation,
2574+ ``ORTSFinalVelocityVariation ( x y z ) `` can be used to specify the variation in each direction
2575+ individually.
25692576- ``ORTSLifespanMultiplier ( x ) `` -- Multiplies the lifetime of particles emitted from this
25702577 emitter by the given (unitless) value. Particle lifetime varies depending on simulation
25712578 data, but if particles seem to last too long a value less than 1 can be entered here, or a
@@ -2607,20 +2614,16 @@ be included to further customize effect emitters:
26072614 A value of 1 is used by default, such that the wind speed used by the simulation is used directly.
26082615 This can be adjusted to prevent particles that shouldn't be influenced by the wind (eg: cylinder
26092616 cocks close to ground level) from flying off in whatever direction the wind is going.
2617+ - ``ORTSParticleOpacity ( o ) `` -- Controls how transparent emitted particles are by multiplying
2618+ texture opacity by the given value (unitless number between 0 and 1). The default setting is 1,
2619+ which doesn't change particle appearance at all. Lower values make particles more transparent,
2620+ until 0 would make all particles invisible.
26102621- ``ORTSPipeArea ( a ) `` -- Niche parameter to adjust the area of the exhaust pipe used by
26112622 the simulation (default units square feet). By default, the area is assumed to be a circle with
26122623 the same diameter as the exhaust particles. However, for non-circular exhausts this can be combined
26132624 with ORTSPositionVariation to give more believable results. Larger areas result in lower exhaust
26142625 speed without changing the number of particles emitted per second, which also allows this to
26152626 be used as a speed multiplier, though ORTSinitialVelocity is preferred for that purpose.
2616- - ``ORTSMaxParticles ( n ) `` -- Override for the maximum number of particles this emitter should
2617- have in the world simultaneously (unitless integer). The default value is 2500 particles, which works
2618- in many cases but may not be appropriate in some unusual circumstances. The limit can be reduced
2619- on less extreme particle emitters to reduce memory use, or can be increased for more extreme emitters
2620- to prevent particles disappearing and/or the reduction in particle emission rate caused by reaching
2621- the particle limit. Do NOT increase the limit if particles are already overlapping; it is often
2622- better to simply reduce the number of particles emitted using ORTSRateMultiplier and/or other
2623- parameters listed here.
26242627- ``ORTSRateMultiplier ( x ) `` -- Multiplies the number of particles emitted per second by the given
26252628 value (unitless). Values less than 1 reduce the rate of particle emission, while values greater than
26262629 1 increase the rate of particle emission. The particle rate is determined by the simulation, but may
@@ -2630,11 +2633,33 @@ be included to further customize effect emitters:
26302633- ``ORTSUseChaoticRandomization ( 0/1 ) `` -- Changes the randomization algorithm used for positions,
26312634 velocities, durations, and so on to be "chaotic" if given a true or 1 value. Default is false or 0,
26322635 giving "smooth" randomization. With the "chaotic" randomization algorithm, the random changes in
2633- position/ velocity/time are entirely random and do not depend on the random values generated for the
2636+ velocity/momentum /time are entirely random and do not depend on the random values generated for the
26342637 previous particle, resulting in sudden dramatic changes. In comparison, the default "smooth"
26352638 randomziation algorithm changes the random values by a small amount for each iteration. The "chaotic"
26362639 algorithm tends to make exhaust that is more spread out and discontinuous, which may be desireable in
26372640 some cases.
2641+
2642+ The following *advanced * parameters have unusual effects that do not directly influence the motion of
2643+ particles and may only be useful in very specific circumstances. Caution should be taken when using any
2644+ of these to ensure the parameter is used correctly, as improper settings can produce displeasing results
2645+ and poor framerates:
2646+
2647+ - ``ORTSMaxParticles ( n ) `` -- Override for the maximum number of particles this emitter should
2648+ have in the world simultaneously (unitless integer). The default value is 2500 particles, which works
2649+ in many cases but may not be appropriate in some unusual circumstances. The limit can be reduced
2650+ on less extreme particle emitters to reduce memory use, or can be increased for more extreme emitters
2651+ to prevent particles disappearing and/or the reduction in particle emission rate caused by reaching
2652+ the particle limit. Do NOT increase the limit if particles are already overlapping; it is often
2653+ better to simply reduce the number of particles emitted using ORTSRateMultiplier and/or other
2654+ parameters listed here.
2655+ - ``ORTSEmissionSpeedLimit ( v ) `` -- Some particle emitters are driven by the simulated flow
2656+ rate of exhaust, which has to make some assumptions about the pressure and volume of exhaust.
2657+ This can lead to unrealistically high speed particles being emitted, so a speed limit can be
2658+ set (default units are meters per second) to keep particle speed reasonable. This is not a hard
2659+ limit, it is gradually enforced as the simulation calculates higher and higher exhaust speed.
2660+ The limit is also applied before considering the emitter velocity factor, so actual exhaust speed
2661+ will vary depending on other settings.
2662+ By default, the limit is 150 meters per second, which will be suitable in most cases.
26382663- ``ORTSGraphic ( "tex" ) `` -- Gives the name and path to the texture that should be used to render
26392664 particles from this emitter. The default texture is "smokemain.ace" for steam-type emitters and
26402665 "dieselsmoke.ace" for diesel-type emitters. If the texture cannot be found from the engine's/wagon's
@@ -2652,29 +2677,31 @@ be included to further customize effect emitters:
26522677 rendered as a square. Rectangular textures will be stretched/squished. Do not change the atlas setting unless you
26532678 are certain of the texture used, as improper settings will be very aesthetically unpleasing.
26542679
2655-
2656- .. index ::
2657- single: ORTSPosition
2658- single: ORTSInitialVelocity
2659- single: ORTSParticleDiameter
26602680
2661- Alternatively, the legacy MSTS data can be skipped entirely and replaced with
2662- equivalent OR specific parameters. In this case, order of data entry does not
2663- matter:
2681+ Note that legacy special effects from MSTS and prior versions of OR use different syntax, simply listing
2682+ a series of numbers rather than using named parameters. The order and arrangement of these values is
2683+ critical, and is interpreted in this order:
2684+
2685+ - Effect location on the locomotive (given as 3 values forming an x, y, z offset in metres
2686+ from the origin of the wagon shape)
2687+ - Effect direction of emission (given as 3 values giving a normal x, y and z)
2688+ - Effect nozzle width (a single number given in metres)
2689+
2690+ To make special effect settings easier to understand, it is recommended to use ``ORTSPosition ``, ``ORTSInitialVelocity ``,
2691+ and ``ORTSParticleDiameter `` to provide these same values. However, if it is desired to continue using the legacy data,
2692+ all ORTS parameters must be entered *after * the legacy numbers, like so::
26642693
26652694 FXName (
2666- ORTSPosition ( -1.0485m 1.0m 2.8m )
2667- ORTSInitialVelocity ( -1 0 0 )
2668- ORTSParticleDiameter ( 0.1m )
2669- Comment ( Insert other ORTS parameters as desired, but skip MSTS data! )
2670- )
2695+ -1.0485 1.0 2.8
2696+ -1 0 0
2697+ 0.1
2698+
2699+ Comment ( ORTS parameters come after MSTS data! )
26712700
2672- - ``ORTSPosition ( x y z ) `` -- defines the width, height, length location of the emitter (in meters by default)
2673- - ``ORTSInitialVelocity ( x y z ) `` -- defines the (+/-) right/left, up/down, forward/backward components of emission direction
2674- (unitless, the particle speed is multiplied by this vector to determine the 3D velocity of particles.
2675- Speed can be divided by inserting values less than 1, or multiplied by inserting values greater than 1.)
2676- - And ``ORTSParticleDiameter ( d ) `` -- gives the nozzle width (in meters by default), which sets the initial
2677- size of each particle
2701+ ORTSInitialVelocityVariation ( 0.25 )
2702+ ORTSFinalVelocityVariation ( 1.0m/s )
2703+ ...etc...
2704+ )
26782705
26792706Auxiliary Water Tenders
26802707'''''''''''''''''''''''
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