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2023-11-02til,checkers: move checkers_rgb_to_uint32() to libtilVito Caputo
Becomes til_rgb_to_uint32(). Nothing functionally changed, just making this generally available for anything wanting to parse an rgb hex string into a uint32 packed pixel in a setup_func.
2023-10-02til: introduce til_value_to_pos() helperVito Caputo
This copies from checkers_value_to_pos() turning it into a libtil helper. It's a common operation in setup_funcs to map a setting value to a numeric position in the list of values.
2023-09-04til: support multi-pass renderingVito Caputo
Modules can now use the til_module_t.finish_frame() return value to trigger re-rendering by returning 1, returning 0 finishes the frame. A smattering of til_module_t.finish_frame() implementations were largely mechanically updated to match this change by returning 0, since nothing actually uses multi-pass rendering yet. The impetus for this is experimenting with the flow module doing two passes of threaded rendering per frame. A first pass to sample the flow field and update the elements, per-cpu, but drawing nothing. Then a second pass to render the elements in a tiled manner.
2023-09-04til,til_fb: introduce a noop_per_cpu fragmenterVito Caputo
This is intended to perhaps be of use for threaded rendering that don't actually produce pixels during their render phase, but still need n_cpus fragments to dispatch the parallel work keying off the fragment.number. Such a renderer might then put its pixels on-screen serially @ finish_frame(), or maybe the rendering functions will get a return value to trigger multi-pass rendering on the same tick.
2023-08-29til: s/til_module_setup_finalize/til_module_settings_finalize/Vito Caputo
Mechanical rename for clarity reasons, primarily to better differentiate from the setup_func style til_module_setup()/til_module_setup_full() functions.
2023-08-29til: s/til_module_setup_randomize/til_module_settings_randomize/Vito Caputo
Mechanical rename for clarity reasons, primarily to better differentiate from the setup_func style til_module_setup()/til_module_setup_full() functions.
2023-08-05til: make builtins first-class modules w/new flagVito Caputo
Also move builtins to a separate listing while at it For now this results in the builtins showing up in the modules list alongside the actual rendering modules. Future work must refine this UX, maybe by adding some metadata to the spec.values for categorizing/prioritizing what's shown always vs. what's present but hidden without asking to be shown hidden stuff or whatever. Just consolidating some junk and working towards every nested module setup going through the same machinery, and always being able to access the builtins.
2023-07-28til: add til_fragmenter_slice_per_cpu_x16() variantVito Caputo
This restores the original til_fragmenter_slice_per_cpu() while adding an explicit x16 variant for what til_fragmenter_slice_per_cpu() had become. The impetus for this is realizing the x16 multiplier is terrible for sparkler's crappy threading, and it really need strictly n_cpus slices for the threading to be beneficial. So I'm just getting rid of the hidden x16 in favor of making it explicit in an _x16 variant. Subsequent commit will pivot all the non-sparkler callers to til_fragmenter_slice_per_cpu_x16().
2023-07-28til: introduce til_module_render_limited() variantVito Caputo
With the introduction of discoverable on-stream contexts, with the intention of modules finding them at runtime for nested rendering, relying exclusively on limiting n_cpus @ til_module_create_context() is no longer adequate. When the nested rendering makes use of a context created elsewhere, it can't make any assumptions about what its n_cpus is, nor should it be attempting to change that value for its use. So this variant just adds a max_cpus parameter for setting an upper bound to whatever is found in the context's n_cpus. The impetus for this is to fix the ref builtin, which you can currently trick into deadlock by performing a nested threaded render within a threaded render. What the ref module should be doing is propagating its own context's n_cpus down as the upper bound, via this new render variant.
2023-07-09til: introduce til_module_setup_full()Vito Caputo
This moves the core til_module_setup() functionality out into a more composable helper with an eye towards all meta-modules using it for doing their module setup instead of all the ad-hoc stuff occurring presently. Since til_module_setup_full() needs more paramaters to influence its behavior, it's not directly usable as a "setup_func". But is trivially wrapped into one, which is what til_module_setup() has now become. It's in the wrapper that users are expected to do specify what's necessary for influencing til_module_setup_full() to do what's appropriate for their needs.
2023-07-07til: introduce til_ticks_now()Vito Caputo
Thin wrapper around gettimeofday(), prolly change the main ticks stuff over to this too.
2023-06-05til: introduce til_module_create_contexts() variantVito Caputo
checkers::fill_module is presently implemented via creating n_cpus identical module contexts, each having n_cpus=1. Establishing a set of cloned per-cpu contexts, allowing threaded rendering using any fill_module, regardless of if that module internally implements threaded rendering. This works fine, but creates some awkwardness for a future where contexts are registered and discoverable within the stream at their respective setup's path. In the checkers::fill_module case, there would be n_cpus contexts at the same path since they share the same til_setup_t. Those need to be dealt with gracefully, ideally making the clones available to another potentially clone-needing module (imagine a checkers::fill_module transitionining to another checkers::fill_module situation, where the transitioned-to fill_module refers to the context by path, it should get all the contexts out of the stream as-is) In this commit I'm adding a more formalized method of creating multiple contexts from the same set of parameters, in preparation for a future where module contexts get registered on the stream at their til_setup_t.path. By putting the cloned creates behind the til API it should at least be relatively trivial to get the on-stream context registration to capture the multiple contexts.
2023-06-03til,modules/rtv: supply settings to til_module_setup_randomize()Vito Caputo
Rather than creating an orphaned settings instance private to til_module_setup_randomize(), the function now requires the settings instance be provided. The one remaining caller of this function is modules::rtv. Now that rtv is responsible for creating the settings beforehand, and the settings may be created with a path prefix, rtv gets its til_module_context_t->setup.path prefixed for all the channel settings. Another improvement is now the channel settings instance gets created from the module name as the settings string. So while it's not yet possible to sparsely specify settings with others being randomized, at least now when log_channels=on is in effect, the printed args include the top-level channel module. Having proper complete paths for the rtv channel modules is especially visible in --print-paths output FYI. An interesting test for exercising all this is: ``` $ src/rototiller --module=rtv,duration=0,context_duration=0,snow_module=none,channels=all,log_channels=on --print-pipes --defaults --go 2>/tmp/channels in another terminal: $ tail -F /tmp/channels ``` watch the chaos unfold
2023-06-03til: add exclusions to til_get_module_names()Vito Caputo
There's often a need to exclude specific modules, though it's often a hacky kludge. It's something relied upon currently for preventing dangerous recursion scenarios, which will likely get fixed up more robustly in the future.
2023-06-03til: add til_get_module_names() helperVito Caputo
Composite modules that want to provide "all" aliases for modules like rtv have to construct a comma-separated string of all module names, usually filtered by some flags. This helper does just that, but it does add yet another open_memstream() user to revisit when those all get fixed up.
2023-05-30til: s/til_module_randomize_setup/til_module_setup_randomize/Vito Caputo
Mechanical rename just to make this consistent with til_module_setup()/til_module_setup_finalize() I should probably do a cleanup pass throughout the til APIs to standardize on a subject-verb-object or subject-object-verb order... Things have become a little inconsistent organically over time
2023-05-30til,*: pivot to til_setup_t for context pathsVito Caputo
This changes til_setup_t* from optional to required for til_module_context_t creation, while dropping the separate path parameter construction and passing throughout.
2023-05-30til: add til_module_setup_finalize() helperVito Caputo
Preparatory commit for til_module_create_context() requiring setups even when there's no til_module_t.setup() method. This helper will produce the minimal til_setup_t in such cases, or hand off the task to til_module_t.setup() when present. Note the need for passing res_setting and res_desc to til_module_t.setup() despite not being a settings-construction scenario. This is because of how modules using nested settings tend to use res_setting for storing the current setting in accessing the nested instance, which must still occur even when just baking the complete setup. It's expected that any composite/meta modules utilizing other modules will use this helper to produce the baked setups, instead of the ad-hoc direct calling of til_module_t.setup() they do presently.
2023-05-11setup: constify settings passed to setup_funcVito Caputo
setup_func isn't formally defined for libtil, but setup_interactively() defacto establishes it and til_module_t.setup() reflects the same signature and calling convention except with til_settings_t constified. This change makes them all consistent in this regard, but there should probably be a formal typedef added for the function. The reason for constifying this is I don't want setup functions directly manipulating the settings instance. In the case of rototiller::setup_interactively() we ensure the stdio-based interactive setup is always the side doing the manipulation of the settings. For a libtil-user like glimmer, it's slightly different beast with GTK+ in the loop, but by preventing the setup_funcs from messing directly with the settings (instead having to describe what they want done iteratively), the front-end always gets its opportunity to maintain its state while doing the described things. Of course, this is mostly a lie, and within libtil the constified til_settings_t gets cast away to modify it in places. But keeping that limited to within libtil is tolerable IMO. We just don't want to see such casts in module code.
2023-02-06til: get rid of the partial knobs implementationVito Caputo
With taps more or less fully implemented, it seems appropriate to get rid of the stubbed out knobs for now. Taps don't express the same things about range and usage knobs aspired towards, but they don't preclude adding such things either. But it seems clear that the way knobs were stubbed won't be complementing taps as things stand currently to add those aspects.
2023-01-20til: pass module to .context_create()/til_module_context_new()Vito Caputo
Let's make it so til_module_context_t as returned from til_module_context_new() can immediately be freed via til_module_context_free(). Previously it was only after the context propagated out to til_module_context_create() that it could be freed that way, as that was where the module member was being assigned. With this change, and wiring up the module pointer into til_module_t.create_context() as well for convenient providing to til_module_context_new(), til_module_t.create_context() error paths can easily cleanup via `return til_module_context_free()` But this does require the til_module_t.destroy_context() be able to safely handle partially constructed contexts, since the mid-create failure freeing won't necessarily have all the members initialized. There will probably be some NULL derefs to fix up, but at least the contexts are zero-initialized @ new.
2023-01-11til: intrdouce a couple new module flagsVito Caputo
TIL_MODULE_HERMETIC: There's likely to be some new modules that are more orchestration style components having external runtime dependencies. Think stuff like a sequencer talking to GNU Rocket, or something that plays back pattern data from external files. Those would need a GNU Rocket process to talk to somewhere, or input pattern file paths. So they shouldn't participate in stuff like random rtv shows unless they have some fallbacks for when the dependencies are unavailable. For pattern data it's realistic to include some builtin patterns to fallback on, but we're not there yet. So this flag when specified should opt out of things like rtv or checkers fill_module random selections. TIL_MODULE_EXPERIMENTAL: Theres no current way to have knowingly unstable/unfinished modules available in-tree for development/collaboration purposes without having them also make stuff like rtv unstable. Modules having this flag set should be excluded from random inclusion without a --experimental or some such runtime flag specified. This commit only assigns values and names for the flags, it doesn't implement anything.
2023-01-11* turn til_fb_fragment_t.stream into a discrete parameterVito Caputo
This was mostly done out of convenience at the expense of turning the fragment struct into more of a junk drawer. But properly cleaning up owned stream pipes on context destroy makes the inappropriateness of being part of til_fb_fragment_t glaringly apparent. Now the stream is just a separate thing passed to context create, with a reference kept in the context for use throughout. Cleanup of the owned pipes on the stream supplied to context create is automagic when the context gets destroyed. Note that despite there being a stream in the module context, the stream to use is still supplied to all the rendering family functions (prepare/render/finish) and it's the passed-in stream which should be used by these functions. This is done to support the possibility of switching out the stream frame-to-frame, which may be interesting. Imagine doing things like a latent stream and a future stream and switching between them on the fly for instance. If there's a sequencing composite module, it could flip between multiple sets of tracks or jump around multiple streams with the visuals immediately flipping accordingly. This should fix the --print-pipes crashing issues caused by lack of cleanup when contexts were removed (like rtv does so often).
2023-01-10*: introduce paths for module contextsVito Caputo
There needs to be a way to address module context instances by name externally, in a manner complementary to settings and taps. This commit adds a string-based path to til_module_context_t, and modifies til_module_create_context() to accept a parent path which is then concatenated with the name of the module to produce the module instance's new path. The name separator used in the paths is '/' just like filesystem paths, but these paths have no relationship to filesystems or files. The root module context creation in rototiller's main simply passes "" as the parent path, resulting in a "/" root as one would expect. There are some obvious complications introduced here however: - checkers in particular creates a context per cpu, simply using the same seed and setup to try make the contexts identical at the same ticks value. With this commit I'm simply passing the incoming path as the parent for creating those contexts, but it's unclear to me if that will work OK. With an eye towards taps deriving their parent path from the context path, I guess these taps would all get the same parent and hash to the same value despite being duplicated. Maybe it Just Works, but one thing is clear - there won't be any way to address the per-cpu taps as-is. Maybe that's desirable though, there's probably not much use in trying to control the taps at the CPU granularity. - when the recursive settings stuff lands, it should bring along the ability to explicitly name settings blocks. Those names should override the module name in constructing the path. I've noted as such in the code. - these paths probably need to be hashed @ initialization time so there needs to be a hash function added to til, and a hash value accompanying the name in the module context. It'd be dumb to keep recomputing the hash when these paths get used for hash table lookups multiple times per frame... there's probably more I'm forgetting right now, but this seems like a good first step. fixup root path
2022-08-07til: til_fb_fragment_t **fragment_ptr all the thingsVito Caputo
Preparatory commit for enabling cloneable/swappable fragments There's an outstanding issue with the til_fb_page_t submission, see comments. Doesn't matter for now since cloning doesn't happen yet, but will need to be addressed before they do.
2022-07-18til: wire seed up to til randomizersVito Caputo
til_setting_desc_t.random() and til_module_randomize_setup() now take seeds. Note they are not taking a pointer to a shared seed, but instead receive the seed by value. If a caller wishes the seed to evolve on every invocation into these functions, it should simply insert a rand_r(&seed) in producing the supplied seed value. Within a given randomizer, the seed evolves when appropriate. But isolating the effects by default seems appropriate, so callers can easily have determinism within their respective scope regardless of how much nested random use occurs.
2022-06-10til: introduce til_frame_plan_t and .cpu_affinityVito Caputo
modules/checkers w/fill_module=$module requires a consistent mapping of cpu to fragnum since it creates a per-cpu til_module_context_t for the fill_module. The existing implementation for threaded rendering maximizes performance by letting *any* scheduled to run thread advance fragnum atomically and render the acquired fragnum indiscriminately. A side effect of this is any given frame, even rendered by the same module, will have a random mapping of cpus/threads to fragnums. With this change, the simple til_module_t.prepare_frame() API of returning a bare fragmenter function is changed to instead return a "frame plan" in til_frame_plan_t. Right now til_frame_plan_t just contains the same fragmenter as before, but also has a .cpu_affinity member for setting if the frame requires a stable relationship of cpu/thread to fragnum. Setting .cpu_affinity should be avoided if unnecessary, and that is the default if you don't mention .cpu_affinity at all when initializing the plan in the ergonomic manner w/designated initializers. This is because the way .cpu_affinity is implemented will leave threads spinning while they poll for *their* next fragnum using atomic intrinsics. There's probably some room for improvement here, but this is good enough for now to get things working and correct.
2022-05-29*: pivot to til_module_context_tVito Caputo
- modules now allocate their contexts using til_module_context_new() instead of [cm]alloc(). - modules simply embed til_module_context_t at the start of their respective private context structs, if they do anything with contexts - modules that do nothing with contexts (lack a create_context() method), will now *always* get a til_module_context_t supplied to their other methods regardless of their create_context() presence. So even if you don't have a create_context(), your prepare_frame() and/or render_fragment() methods can still access seed and n_cpus from within the til_module_context_t passed in as context, *always*. - modules that *do* have a create_context() method, implying they have their own private context type, will have to cast the til_module_context_t supplied to the other methods to their private context type. By embedding the til_module_context_t at the *start* of their private context struct, a simple cast is all that's needed. If it's placed somewhere else, more annoying container_of() style macros are needed - this is strongly discouraged, just put it at the start of struct. - til_module_create_context() now takes n_cpus, which may be set to 0 for automatically assigning the number of threads in its place. Any non-zero value is treated as an explicit n_cpus, primarily intended for setting it to 1 for single-threaded contexts necessary when embedded within an already-threaded composite module. - modules like montage which open-coded a single-threaded render are now using the same til_module_render_fragment() as everything else, since til_module_create_context() is accepting n_cpus. - til_module_create_context() now produces a real type, not void *, that is til_module_context_t *. All the other module context functions now operate on this type, and since til_module_context_t.module tracks the module this context relates to, those functions no longer require both the module and context be passed in. This is especially helpful for compositing modules which do a lot of module context creation and destruction; the module handle is now only needed to create the contexts. Everything else operating on that context only needs the single context pointer, not module+context pairs, which was unnecessarily annoying. - if your module's context can be destroyed with a simple free(), without any deeper knowledge or freeing of nested pointers, you can now simply omit destroy_context() altogether. When destroy_context() is missing, til_module_context_free() will automatically use libc's free() on the pointer returned from your create_context() (or on the pointer that was automatically created if you omitted create_context() too, for the bare til_module_context_t that got created on your behalf anyways). For the most part, these changes don't affect module creation. In some ways this eases module creation by making it more convenient access seed and n_cpus if you had no further requirement for a context struct. In other ways it's slightly annoying to have to do type-casts when you're working with your own context type, since before it was all void* and didn't require casts when assigning to your typed context variables. The elimination for requiring a destroy_context() method in simple free() of private context scenarios removes some boilerplate in simple cases. I think it's a wash for module writers, or maybe a slight win for the simple cases.
2022-05-21til: supply a seed to til_module_t.create_context()Vito Caputo
In the recent surge of ADD-style rtv+compose focused development, a bunch of modules were changed to randomize initial states at context_create() so they wouldn't be so repetitive. But the way this was done in a way that made it impossible to suppress the randomized initial state, which sometimes may be desirable in compositions. Imagine for instance something like the checkers module, rendering one module in the odd cells, and another module into the even cells. Imagine if these modules are actually the same, but if checkers used one seed for all the odd cells and another seed for all the even cells. If the modules used actually utilized the seed provided, checkers would be able to differentiate the odd from even by seeding them differently even when the modules are the same. This commit is a step in that direction, but rototiller and all the composite modules (rtv,compose,montage) are simply passing rand() as the seeds. Also none of the modules have yet been modified to actually make use of these seeds. Subsequent commits will update modules to seed their pseudo-randomized initial state from the seed value rather than always calling things like rand() themselves.
2022-05-01til: introduce some generic fragmenters for convenienceVito Caputo
Most of the threaded modules have settled down on two basic forms of fragmenter function: 1. a slice per cpu, where tile-oriented locality isn't useful 2. ~64x64 tiles, in scenarios where screen-space locality helps Now that n_cpus is wired up to the fragmenter, #1 can be fulfilled without requiring a module-private context plumbing n_cpus from create_context(). A future commit will replace some module-specific fragmenters by returning one of these instead as res_fragmenter in their prepare_frame(), wherever applicable.
2022-05-01til: wire n_cpus up to the fragmenter functionVito Caputo
Fragmenting is often dimensioned according to the number of cpus, and by not supplying this to the fragmenter it was made rather common for module contexts to plumb this themselves - in some cases incorporating a context type/create/destroy rigamarole for the n_cpus circuit alone. So just plumb it in libtil, and the prepare_frame functions can choose to ignore it if they have something more desirable onhand. Future commits will remove a bunch of n_cpus from module contexts in favor of this.
2022-04-25til: add til_module_t.flags and TIL_MODULE_OVERLAYABLEVito Caputo
For modules which are overlay-appropriate, they should indicate it when initializing their respective til_module_t. If they intend to participate in automagic compositing as overlays anyways.
2022-04-24*: s/void */til_setup_t */Vito Caputo
This brings something resembling an actual type to the private objects returrned in *res_setup. Internally libtil/rototiller wants this to be a til_setup_t, and it's up to the private users of what's returned in *res_setup to embed this appropriately and either use container_of() or casting when simply embedded at the start to go between til_setup_t and their private containing struct. Everywhere *res_setup was previously allocated using calloc() is now using til_setup_new() with a free_func, which til_setup_new() will initialize appropriately. There's still some remaining work to do with the supplied free_func in some modules, where free() isn't quite appropriate. Setup freeing isn't actually being performed yet, but this sets the foundation for that to happen in a subsequent commit that cleans up the setup leaks. Many modules use a static default setup for when no setup has been provided. In those cases, the free_func would be NULL, which til_setup_new() refuses to do. When setup freeing actually starts happening, it'll simply skip freeing when til_setup_t.free_func is NULL.
2022-04-22til: make til_module_randomize_setup() return -errnoVito Caputo
This makes the arg return optional by using a res_arg pointer, instead returning -ENOMEM when it would have returned NULL on allocation failures. This also makes it possible to detect when no setup was performed, by returning 0 in such a case. Now returns 1 when setup occurs and res pointers populated.
2022-04-22til: add til_module_randomize_setup() from rtvVito Caputo
This commit pulls the setup randomizer out of rtv into libtil proper, so other modules may make use of it. Other than adding an assert no functional changes occurred. It may make sense to split this into two functions; one which takes a til_module_t as-is, and a lower-level bare setup function callback based function that doesn't know about til_module_t the former would call into. That way generic setup randomization can occur (the same setup machinery is used in video contexts for example) without necessarily having a til_module_t on hand.
2022-03-30*: wire up context-specific setup instancesVito Caputo
This is a preparatory commit for cleaning up the existing sloppy global-ish application of settings during the iterative _setup() call sequences. Due to how this has evolved from a very rudimentary thing enjoying many assumptions about there ever only being a single module instance being configured by the settings, there's a lot of weirdness and inconsistency surrounding module setup WRT changes being applied instantaneously to /all/ existing and future context's renderings of a given module vs. requiring a new context be created to realize changes. This commit doesn't actually change any of that, but puts the plumbing in place for the setup methods to allocate and initialize a private struct encapsulating the parsed and validated setup once the settings are complete. This opaque setup pointer will then be provided to the associated create_context() method as the setup pointer. Then the created context can configure itself using the provided setup when non-NULL, or simply use defaults when NULL. A future commit will update the setup methods to allocate and populate their respective setup structs, adding the structs as needed, as well as updating their create_context() methods to utilize those setups. One consequence of these changes when fully realized will be that every setting change will require a new context be created from the changed settings for the change to be realized. For settings appropriately manipulated at runtime the concept of knobs was introduced but never finished. That will have to be finished in the future to enable more immediate/interactive changing of settings-like values appropriate for interactive manipulation
2022-03-19*: de-constify til_setting_t throughoutVito Caputo
Now that til_setting_t.desc is not only a thing, but a thing that is intended to be refreshed regularly in the course of things like GUI interactive settings construction, it's not really appropriate to try even act like this these are const anymore.
2022-03-19til: add til_module_destroy_context() helperVito Caputo
2022-03-19*: drop til_module_t.licenseVito Caputo
Originally the thinking was that rototiller modules would become dlopen()ed shared objects, and that it would make sense to let them be licensed differently. At this time only some modules I have written were gplv3, Phil's modules are all gplv2, and I'm not inclined to pivot towards a dlopen model. So this commit drops the license field from til_module_t, relicenses my v3 code to v2, and adds a gplv2 LICENSE file to the source root dir. As of now rototiller+libtil and all its modules are simply gplv2, and anything linking in libtil must use a gplv2 compatible license - the expectation is that you just use gplv2.
2022-03-12til_settings: always describe relevant settingsVito Caputo
The existing iterative *_setup() interface only described settings not found, quietly accepting usable settings already present in the til_settings_t. This worked fine for the existing interactive text setup thing, but it's especially problematic for providing a GUI setup frontend. This commit makes it so the *_setup() methods always describe undescribed settings they recognize, leaving the setup frontend loop calling into the *_setup() methods to both apply the description validation if wanted and actually tie the description to respective setting returned by the _setup() methods as being related to the returned description. A new helper called til_settings_get_and_describe_value() has been introduced primarily for use of module setup methods to simplify this nonsense, replacing the til_settings_get_value() calls and surrounding logic, but retaining the til_setting_desc_t definitions largely verbatim. This also results in discarding of some ad-hoc til_setting_desc_check() calls, now that there's a centralized place where settings become "described" (setup_interactively in the case of rototiller). Now a GUI frontend (like glimmer) would just provide its own setup_interactively() equivalent for constructing its widgets for a given *_setup() method's chain of returned descs. Whereas in the past this wasn't really feasible unless there was never going to be pre-supplied settings. I suspect the til_setting_desc_check() integration into setup_interactively() needs more work, but I think this is good enough for now and I'm out of spare time for the moment.
2021-10-01*: librototiller->libtilVito Caputo
Largely mechanical rename of librototiller -> libtil, but introducing a til_ prefix to all librototiller (now libtil) functions and types where a rototiller prefix was absent. This is just a step towards a more libized librototiller, and til is just a nicer to type/read prefix than rototiller_.
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