From c9e28c3f02fb174ee6edbccd9f1edd83373d8e80 Mon Sep 17 00:00:00 2001 From: Sara Date: Sat, 2 Dec 2023 16:57:02 +0100 Subject: [PATCH] portfolio --- .gitignore | 56 ++++ CMakeLists.txt | 13 + LICENSE | 339 +++++++++++++++++++++++ README.md | 1 + ecs.c | 717 +++++++++++++++++++++++++++++++++++++++++++++++++ ecs.h | 131 +++++++++ 6 files changed, 1257 insertions(+) create mode 100644 .gitignore create mode 100644 CMakeLists.txt create mode 100644 LICENSE create mode 100644 README.md create mode 100644 ecs.c create mode 100644 ecs.h diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..ae83443 --- /dev/null +++ b/.gitignore @@ -0,0 +1,56 @@ +[Bb]uild/ +[Dd]ebug/ +[Rr]elease/ + +# Prerequisites +*.d + +# Object files +*.o +*.ko +*.obj +*.elf + +# Linker output +*.ilk +*.map +*.exp + +# Precompiled Headers +*.gch +*.pch + +# Libraries +*.lib +*.a +*.la +*.lo + +# Shared objects (inc. Windows DLLs) +*.dll +*.so +*.so.* +*.dylib + +# Executables +*.exe +*.out +*.app +*.i*86 +*.x86_64 +*.hex + +# Debug files +*.dSYM/ +*.su +*.idb +*.pdb + +# Kernel Module Compile Results +*.mod* +*.cmd +.tmp_versions/ +modules.order +Module.symvers +Mkfile.old +dkms.conf diff --git a/CMakeLists.txt b/CMakeLists.txt new file mode 100644 index 0000000..3e0ee91 --- /dev/null +++ b/CMakeLists.txt @@ -0,0 +1,13 @@ +cmake_minimum_required(VERSION 3.17) + +project(ecs) + +file( + GLOB + SOURCE + "./*.c" +) + +set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-incompatible-pointer-types") + +add_library(ecs ${SOURCE}) diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..d159169 --- /dev/null +++ b/LICENSE @@ -0,0 +1,339 @@ + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +License is intended to guarantee your freedom to share and change free +software--to make sure the software is free for all its users. This +General Public License applies to most of the Free Software +Foundation's software and to any other program whose authors commit to +using it. (Some other Free Software Foundation software is covered by +the GNU Lesser General Public License instead.) You can apply it to +your programs, too. + + When we speak of free software, we are referring to freedom, not +price. Our General Public Licenses are designed to make sure that you +have the freedom to distribute copies of free software (and charge for +this service if you wish), that you receive source code or can get it +if you want it, that you can change the software or use pieces of it +in new free programs; and that you know you can do these things. + + To protect your rights, we need to make restrictions that forbid +anyone to deny you these rights or to ask you to surrender the rights. +These restrictions translate to certain responsibilities for you if you +distribute copies of the software, or if you modify it. + + For example, if you distribute copies of such a program, whether +gratis or for a fee, you must give the recipients all the rights that +you have. You must make sure that they, too, receive or can get the +source code. And you must show them these terms so they know their +rights. + + We protect your rights with two steps: (1) copyright the software, and +(2) offer you this license which gives you legal permission to copy, +distribute and/or modify the software. + + Also, for each author's protection and ours, we want to make certain +that everyone understands that there is no warranty for this free +software. If the software is modified by someone else and passed on, we +want its recipients to know that what they have is not the original, so +that any problems introduced by others will not reflect on the original +authors' reputations. + + Finally, any free program is threatened constantly by software +patents. We wish to avoid the danger that redistributors of a free +program will individually obtain patent licenses, in effect making the +program proprietary. To prevent this, we have made it clear that any +patent must be licensed for everyone's free use or not licensed at all. + + The precise terms and conditions for copying, distribution and +modification follow. + + GNU GENERAL PUBLIC LICENSE + TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + + 0. This License applies to any program or other work which contains +a notice placed by the copyright holder saying it may be distributed +under the terms of this General Public License. The "Program", below, +refers to any such program or work, and a "work based on the Program" +means either the Program or any derivative work under copyright law: +that is to say, a work containing the Program or a portion of it, +either verbatim or with modifications and/or translated into another +language. (Hereinafter, translation is included without limitation in +the term "modification".) Each licensee is addressed as "you". + +Activities other than copying, distribution and modification are not +covered by this License; they are outside its scope. The act of +running the Program is not restricted, and the output from the Program +is covered only if its contents constitute a work based on the +Program (independent of having been made by running the Program). +Whether that is true depends on what the Program does. + + 1. You may copy and distribute verbatim copies of the Program's +source code as you receive it, in any medium, provided that you +conspicuously and appropriately publish on each copy an appropriate +copyright notice and disclaimer of warranty; keep intact all the +notices that refer to this License and to the absence of any warranty; +and give any other recipients of the Program a copy of this License +along with the Program. + +You may charge a fee for the physical act of transferring a copy, and +you may at your option offer warranty protection in exchange for a fee. + + 2. You may modify your copy or copies of the Program or any portion +of it, thus forming a work based on the Program, and copy and +distribute such modifications or work under the terms of Section 1 +above, provided that you also meet all of these conditions: + + a) You must cause the modified files to carry prominent notices + stating that you changed the files and the date of any change. + + b) You must cause any work that you distribute or publish, that in + whole or in part contains or is derived from the Program or any + part thereof, to be licensed as a whole at no charge to all third + parties under the terms of this License. + + c) If the modified program normally reads commands interactively + when run, you must cause it, when started running for such + interactive use in the most ordinary way, to print or display an + announcement including an appropriate copyright notice and a + notice that there is no warranty (or else, saying that you provide + a warranty) and that users may redistribute the program under + these conditions, and telling the user how to view a copy of this + License. (Exception: if the Program itself is interactive but + does not normally print such an announcement, your work based on + the Program is not required to print an announcement.) + +These requirements apply to the modified work as a whole. If +identifiable sections of that work are not derived from the Program, +and can be reasonably considered independent and separate works in +themselves, then this License, and its terms, do not apply to those +sections when you distribute them as separate works. But when you +distribute the same sections as part of a whole which is a work based +on the Program, the distribution of the whole must be on the terms of +this License, whose permissions for other licensees extend to the +entire whole, and thus to each and every part regardless of who wrote it. + +Thus, it is not the intent of this section to claim rights or contest +your rights to work written entirely by you; rather, the intent is to +exercise the right to control the distribution of derivative or +collective works based on the Program. + +In addition, mere aggregation of another work not based on the Program +with the Program (or with a work based on the Program) on a volume of +a storage or distribution medium does not bring the other work under +the scope of this License. + + 3. You may copy and distribute the Program (or a work based on it, +under Section 2) in object code or executable form under the terms of +Sections 1 and 2 above provided that you also do one of the following: + + a) Accompany it with the complete corresponding machine-readable + source code, which must be distributed under the terms of Sections + 1 and 2 above on a medium customarily used for software interchange; or, + + b) Accompany it with a written offer, valid for at least three + years, to give any third party, for a charge no more than your + cost of physically performing source distribution, a complete + machine-readable copy of the corresponding source code, to be + distributed under the terms of Sections 1 and 2 above on a medium + customarily used for software interchange; or, + + c) Accompany it with the information you received as to the offer + to distribute corresponding source code. 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Any attempt +otherwise to copy, modify, sublicense or distribute the Program is +void, and will automatically terminate your rights under this License. +However, parties who have received copies, or rights, from you under +this License will not have their licenses terminated so long as such +parties remain in full compliance. + + 5. You are not required to accept this License, since you have not +signed it. However, nothing else grants you permission to modify or +distribute the Program or its derivative works. These actions are +prohibited by law if you do not accept this License. Therefore, by +modifying or distributing the Program (or any work based on the +Program), you indicate your acceptance of this License to do so, and +all its terms and conditions for copying, distributing or modifying +the Program or works based on it. + + 6. Each time you redistribute the Program (or any work based on the +Program), the recipient automatically receives a license from the +original licensor to copy, distribute or modify the Program subject to +these terms and conditions. You may not impose any further +restrictions on the recipients' exercise of the rights granted herein. +You are not responsible for enforcing compliance by third parties to +this License. + + 7. If, as a consequence of a court judgment or allegation of patent +infringement or for any other reason (not limited to patent issues), +conditions are imposed on you (whether by court order, agreement or +otherwise) that contradict the conditions of this License, they do not +excuse you from the conditions of this License. If you cannot +distribute so as to satisfy simultaneously your obligations under this +License and any other pertinent obligations, then as a consequence you +may not distribute the Program at all. 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Many people have made +generous contributions to the wide range of software distributed +through that system in reliance on consistent application of that +system; it is up to the author/donor to decide if he or she is willing +to distribute software through any other system and a licensee cannot +impose that choice. + +This section is intended to make thoroughly clear what is believed to +be a consequence of the rest of this License. + + 8. If the distribution and/or use of the Program is restricted in +certain countries either by patents or by copyrighted interfaces, the +original copyright holder who places the Program under this License +may add an explicit geographical distribution limitation excluding +those countries, so that distribution is permitted only in or among +countries not thus excluded. In such case, this License incorporates +the limitation as if written in the body of this License. + + 9. The Free Software Foundation may publish revised and/or new versions +of the General Public License from time to time. Such new versions will +be similar in spirit to the present version, but may differ in detail to +address new problems or concerns. + +Each version is given a distinguishing version number. If the Program +specifies a version number of this License which applies to it and "any +later version", you have the option of following the terms and conditions +either of that version or of any later version published by the Free +Software Foundation. If the Program does not specify a version number of +this License, you may choose any version ever published by the Free Software +Foundation. + + 10. If you wish to incorporate parts of the Program into other free +programs whose distribution conditions are different, write to the author +to ask for permission. For software which is copyrighted by the Free +Software Foundation, write to the Free Software Foundation; we sometimes +make exceptions for this. Our decision will be guided by the two goals +of preserving the free status of all derivatives of our free software and +of promoting the sharing and reuse of software generally. + + NO WARRANTY + + 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY +FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN +OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES +PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED +OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS +TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE +PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, +REPAIR OR CORRECTION. + + 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR +REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, +INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING +OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED +TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY +YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER +PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE +POSSIBILITY OF SUCH DAMAGES. + + END OF TERMS AND CONDITIONS + + How to Apply These Terms to Your New Programs + + If you develop a new program, and you want it to be of the greatest +possible use to the public, the best way to achieve this is to make it +free software which everyone can redistribute and change under these terms. + + To do so, attach the following notices to the program. It is safest +to attach them to the start of each source file to most effectively +convey the exclusion of warranty; and each file should have at least +the "copyright" line and a pointer to where the full notice is found. + + + Copyright (C) + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + +Also add information on how to contact you by electronic and paper mail. + +If the program is interactive, make it output a short notice like this +when it starts in an interactive mode: + + Gnomovision version 69, Copyright (C) year name of author + Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, the commands you use may +be called something other than `show w' and `show c'; they could even be +mouse-clicks or menu items--whatever suits your program. + +You should also get your employer (if you work as a programmer) or your +school, if any, to sign a "copyright disclaimer" for the program, if +necessary. Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the program + `Gnomovision' (which makes passes at compilers) written by James Hacker. + + , 1 April 1989 + Ty Coon, President of Vice + +This General Public License does not permit incorporating your program into +proprietary programs. If your program is a subroutine library, you may +consider it more useful to permit linking proprietary applications with the +library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. diff --git a/README.md b/README.md new file mode 100644 index 0000000..8b13789 --- /dev/null +++ b/README.md @@ -0,0 +1 @@ + diff --git a/ecs.c b/ecs.c new file mode 100644 index 0000000..aae1ef5 --- /dev/null +++ b/ecs.c @@ -0,0 +1,717 @@ +#include "ecs.h" +#include +#include +#include +#include +#include + +typedef unsigned char BYTE; + +typedef struct ECSsystem { + ecsSystemFn fn; + ecsComponentQuery query; + int maxThreads; + int execOrder; +} ECSsystem; + +/** + * \brief Structure to represent a task the ECS needs to perform after systems finish running. + * \note Not every member is used by type and thus some might be able to be left uninitialized. + */ +typedef struct ecsTask { + enum ECS_TASKTYPE { + ECS_ENTITY_DESTROY, //! Uses .entity + ECS_COMPONENTS_DETACH, //! Uses .entity and .components.mask + ECS_SYSTEM_CREATE, //! Uses .system and .components + ECS_SYSTEM_DESTROY, //! Uses .system + } type; + + ecsEntityId entity; //! relevant entity id + ECSsystem system; //! relevant system function pointer + ecsComponentQuery components; //! relevant components +} ecsTask; + +typedef struct ECSentityData { + ecsEntityId id; + ecsComponentMask mask; +} ECSentityData; + +typedef struct ECScomponentType { + ecsComponentMask id; + size_t stride; + size_t componentSize; + size_t size; + void* begin; +} ECScomponentType; + +typedef struct ECScomponentList { + size_t size; + ECScomponentType* begin; +} ECScomponentList; + +typedef struct ECSentityList { + size_t size; + size_t nextValidId; + ECSentityData* begin; +} ECSentityList; + +typedef struct ECSsystemList { + size_t size; + ECSsystem* begin; +} ECSsystemList; + +typedef struct ECStaskQueue { + size_t size; + ecsTask* begin; +} ECStaskQueue; + +// forward declare helper functions +static inline int ecsResizeComponents(size_t size); +static inline int ecsResizeComponentType(ECScomponentType* type, size_t size); +static inline int ecsResizeEntities(size_t size); +static inline int ecsResizeSystems(size_t size); +static inline int ecsPushTaskStack(void); +static inline void ecsClearTasks(void); +static inline ECSentityData* ecsFindEntityData(ecsEntityId id); +static inline ECScomponentType* ecsFindComponentType(ecsComponentMask id); +static inline ECSsystem* ecsFindSystem(ecsSystemFn fn); +static inline void* ecsFindComponentFor(ECScomponentType* type, ecsEntityId id); +void ecsPushTask(ecsTask task); + + +ECSentityList ecsEntities; +ECScomponentList ecsComponents; +ECSsystemList ecsSystems; +ECStaskQueue ecsTasks; +int ecsIsInit = 0; + + +void ecsInit() +{ + assert(!ecsIsInit); + + ecsEntities.nextValidId = 1; + ecsEntities.begin = NULL; + ecsComponents.begin = NULL; + ecsSystems.begin = NULL; + ecsTasks.begin = NULL; + ecsEntities.size = ecsComponents.size = ecsSystems.size = ecsTasks.size = 0; + + ecsIsInit = 1; +} + +void ecsTerminate() +{ + assert(ecsIsInit); + + if(ecsEntities.begin) free(ecsEntities.begin); + if(ecsSystems.begin) free(ecsSystems.begin); + if(ecsTasks.begin) free(ecsTasks.begin); + + if(ecsComponents.begin) + { + ECScomponentType* type; + for(size_t i = 0; i < ecsComponents.size; i++) + { + type = ecsComponents.begin + i; + if(type->begin) + free(type->begin); + } + free(ecsComponents.begin); + } + + ecsIsInit = 0; +} + +ecsComponentMask ecsMakeComponentType(size_t stride) +{ + // avoid going out of bounds on the bitmask + if (ecsComponents.size == sizeof(ecsComponentMask) * 8) return nocomponent; + + ecsComponentMask mask = (0x1ll << ecsComponents.size); // calculate component mask + + // add an element to end of array + if(ecsResizeComponents(ecsComponents.size + 1)) + { + ECScomponentType ntype = (ECScomponentType) { // prepare specs of new component type + .size = 0, .begin = NULL, .id = mask, .stride = (stride + sizeof(ecsEntityId)), .componentSize = stride + }; + // copy prepared component data + memmove(ecsComponents.begin + ecsComponents.size-1, &ntype, sizeof(ntype)); + return mask; + } + + return nocomponent; +} + +// +// COMPONENTS +// + +void ecsSortComponents(ECScomponentType* type) +{ + int swaps; + void* a; + void* b; + ecsEntityId enta; + ecsEntityId entb; + void* temp = malloc(type->stride); + + // linear sort + do { + swaps = 0; + for(size_t i = 1; i < type->size; ++i) + { + a = ((BYTE*)type->begin) + type->stride * (i-1); + b = ((BYTE*)type->begin) + type->stride * i; + enta = *(ecsEntityId*)a; + entb = *(ecsEntityId*)b; + + if(enta > entb) + { + swaps++; + memcpy(temp, b, type->stride); + memcpy(b, a, type->stride); + memcpy(a, temp, type->stride); + } + } + } while(swaps > 0); +} + +void* ecsGetComponentPtr(ecsEntityId e, ecsComponentMask c) +{ + ECScomponentType* ctype = ecsFindComponentType(c); + + ecsEntityId* ptr = ecsFindComponentFor(ctype, e); + if(ptr == NULL) return NULL; // component for e, c combination does not exist + + return (void*)(ptr + 1); +} + +void ecsAttachComponent(ecsEntityId e, ecsComponentMask c) +{ + ECSentityData* entity = ecsFindEntityData(e); + ECScomponentType* ctype = ecsFindComponentType(c); + + if(ctype == NULL) return; // component type does not exist + if(entity == NULL) return; // no such entity + if(((entity->mask) & c) != 0) return; // component already exists + + if(ecsResizeComponentType(ctype, ctype->size + 1)) + { + BYTE* eid = ((BYTE*)ctype->begin) + ((ctype->size-1) * ctype->stride); // get last item of the list as its entityId block + memset(eid, 0x0, ctype->stride); // zero new component + memcpy(eid, &e, sizeof(ecsEntityId)); // set entityId block + entity->mask |= c; // register that component was added to entity + ecsSortComponents(ctype); + } +} + +void ecsAttachComponents(ecsEntityId e, ecsComponentMask q) +{ + ecsComponentMask c; // single component mask + for(size_t i = 0; i < ecsComponents.size; i++) + { + c = (0x1ll << i); + if((q & c) != 0) // query contains this mask + ecsAttachComponent(e, c); + } +} + +void ecsDetachComponent(ecsEntityId e, ecsComponentMask c) +{ + ECScomponentType* ctype = ecsFindComponentType(c); + + if(ctype == NULL) return; // no such component type + + ECSentityData* entity = ecsFindEntityData(e); + + if(entity == NULL) return; // no such entity + if((entity->mask & c) == 0) return; // entity does not have component + + void* block = ecsFindComponentFor(ctype, e); + + if(block == NULL) return; // no component block for entity found + + uintptr_t lenafter = (uintptr_t)(((BYTE*)ctype->begin + ctype->size * ctype->stride) - (BYTE*)block); + lenafter -= ctype->stride; + // move last element into to-be-destroyed element + memmove(block, block + ctype->stride, lenafter); + + // shorten array by one stride + ecsResizeComponentType(ctype, (ctype->size)-1); + entity->mask &= ~c; +} + +void ecsDetachComponents(ecsEntityId e, ecsComponentMask c) +{ ecsPushTask((ecsTask){.type=ECS_COMPONENTS_DETACH, .components={ .mask=c }, .entity=e}); } +void ecsTaskDetachComponents(ecsEntityId e, ecsComponentMask q) +{ + ecsComponentMask id; + for(size_t i = 0; i < ecsComponents.size; i++) + { + id = (0x1ll << i); + if((q & id) != 0) // query contains component type at i + ecsDetachComponent(e, id); + } +} + +// +// ENTITIES +// + +ecsEntityId ecsCreateEntity(ecsComponentMask components) +{ + // register an id that is unique for the runtime of the ecs + ecsEntityId id = ecsEntities.nextValidId; + ecsEntities.nextValidId++; + + // prepare values + ECSentityData entity = (ECSentityData) { + .mask = 0x0, .id = id + }; + + // resize entities list + if(ecsResizeEntities(ecsEntities.size + 1)) + { + // copy prepared values + memmove((ecsEntities.begin + ecsEntities.size - 1), &entity, sizeof(entity)); + + // attach requested components + ecsAttachComponents(id, components); + return id; + } + return noentity; +} + +ecsEntityId ecsGetComponentMask(ecsEntityId entity) +{ + ECSentityData* data = ecsFindEntityData(entity); + return data != NULL ? data->mask : nocomponent; +} + +int ecsValidEntity(ecsEntityId entity) +{ + return ecsFindEntityData(entity) != NULL; +} + +void ecsDestroyEntity(ecsEntityId e) +{ ecsPushTask((ecsTask){.type=ECS_ENTITY_DESTROY, .entity=e}); } +void ecsTaskDestroyEntity(ecsEntityId e) +{ + ECSentityData* data = ecsFindEntityData(e); + if(data == NULL) return; // no such entity + + // destroy all components owned by entity + ecsTaskDetachComponents(e, data->mask); + + // get the last element of the entities array + uintptr_t countAfter = (uintptr_t)((ecsEntities.begin + ecsEntities.size) - data); + assert(countAfter < ecsEntities.size); + // copy last into to-be-deleted entity + memmove(data, data+1, sizeof(ECSentityData) * countAfter); + + // resize + ecsResizeEntities(ecsEntities.size - 1); +} + +// +// SYSTEMS +// + +int matchQuery(ecsComponentQuery query, ecsComponentMask mask) +{ + if(query.comparison == ECS_QUERY_ANY) + return (mask & query.mask) != 0; + else if(query.comparison == ECS_QUERY_ALL) + return (mask & query.mask) == query.mask; + return 0; +} + +typedef struct ecsRunSystemArgs { + ecsSystemFn fn; + ecsEntityId* entities; + ecsComponentMask* components; + size_t count; + float deltaTime; +} ecsRunSystemArgs; + +void* ecsRunSystem(void* args) +{ + ecsRunSystemArgs* arg = args; + arg->fn(arg->entities, arg->components, arg->count, arg->deltaTime); + return NULL; +} + +void ecsRunSystems(float deltaTime) +{ + ECSsystem system; + ECSentityData entity; + size_t entityCount = ecsEntities.size; + + pthread_t* threads = NULL; + ecsRunSystemArgs* threadArgs = NULL; + + for(size_t i = 0; i < ecsSystems.size; ++i) + { + system = ecsSystems.begin[i]; + + // ECS_NOQUERY systems get run exactly once per ecsRunSystems call + // with entity and components arguments on NULL + // and count argument on 0 + if(system.query.comparison == ECS_NOQUERY) + { + system.fn(NULL, NULL, 0, deltaTime); + } + else + { + // look for all entities matching the query + // first allocate entity and component lists the size of the number of entities + ecsEntityId* entityList = malloc((entityCount + 1) * sizeof(ecsEntityId)); + ecsComponentMask* componentList = malloc((entityCount + 1) * sizeof(ecsComponentMask)); + assert(entityList != NULL); + assert(componentList != NULL); + + // then search for entities that match the query + size_t total = 0; + for(size_t j = 0; j < entityCount; ++j) + { + entity = ecsEntities.begin[j]; + if (matchQuery(system.query, entity.mask)) + { + assert(total < entityCount); + entityList[total] = entity.id; + componentList[total] = entity.mask; + total++; + } + } + + size_t threadCount = system.maxThreads; + if(threadCount > 0) + threadCount = threadCount > total ? total : threadCount; + else + threadCount = 1; + + // dont use threads + if(threadCount <= 1) + { + system.fn(entityList, componentList, total, deltaTime); + } + // use threads + else + { + // avoid creating more threads than there are matching entities + threads = realloc(threads, threadCount * sizeof(pthread_t)); + threadArgs = realloc(threadArgs, threadCount * sizeof(ecsRunSystemArgs)); + + // for each thread, create a runsystemargs instance describing it's area of influence + // then create the thread + size_t perThreadCount = total - (total % (threadCount-1)); + perThreadCount = perThreadCount / (threadCount-1); + size_t remainder = total % (threadCount-1); + for(int j = 0; j < threadCount; ++j) + { + threadArgs[j].fn = system.fn; + threadArgs[j].entities = entityList + perThreadCount * j; + threadArgs[j].components = componentList + perThreadCount * j; + threadArgs[j].count = (j == threadCount-1) ? remainder : perThreadCount; + threadArgs[j].deltaTime = deltaTime; + + pthread_create(threads + j, NULL, &ecsRunSystem, threadArgs + j); + } + + // wait for completion of all threads + for(int j = 0; j < threadCount; ++j) + { + pthread_join(threads[j], NULL); + } + } + + // clean up + free(entityList); + free(componentList); + } + } + if(threads != NULL) + free(threads); + if(threadArgs != NULL) + free(threadArgs); + + ecsRunTasks(); +} + +void ecsSortSystems() +{ + int swaps; + ECSsystem tmp; + + do + { + swaps = 0; + for(int i = 1; i < ecsSystems.size; ++i) + { + if(ecsSystems.begin[i-1].execOrder > ecsSystems.begin[i].execOrder) + { + memcpy(&tmp, &ecsSystems.begin[i-1], sizeof(ECSsystem)); + memcpy(&ecsSystems.begin[i-1], &ecsSystems.begin[i], sizeof(ECSsystem)); + memcpy(&ecsSystems.begin[i], &tmp, sizeof(ECSsystem)); + swaps++; + } + } + } + while(swaps > 0); +} + +void ecsEnableSystem(ecsSystemFn fn, ecsComponentMask query, ecsQueryComparison comp, int maxThreads, int execOrder) +{ + ecsPushTask((ecsTask) + { + .type=ECS_SYSTEM_CREATE, + .system=(ECSsystem) + { + .fn = fn, + .maxThreads = maxThreads, + .execOrder = execOrder, + .query=(ecsComponentQuery) + { + .mask=query, + .comparison=comp + } + } + }); +} + +void ecsTaskEnableSystem(ECSsystem system) +{ + if(ecsResizeSystems(ecsSystems.size + 1)) + { + ECSsystem* last = (ecsSystems.begin + ecsSystems.size - 1); + memcpy(last, &system, sizeof(ECSsystem)); + ecsSortSystems(); + } +} + +void ecsDisableSystem(ecsSystemFn fn) +{ ecsPushTask((ecsTask){ .type=ECS_SYSTEM_DESTROY, .system=fn }); } +void ecsTaskDisableSystem(ecsSystemFn fn) +{ + // calculate distance between end and to replace + ECSsystem* to_replace = ecsFindSystem(fn); + ECSsystem* end = ecsSystems.begin + ecsSystems.size; + size_t dist = (end - to_replace) - 1; + + // shift everything after to-be-deleted item back by one (overwriting to-be-deleted) + memmove(to_replace, to_replace + 1, dist * sizeof(ECSsystem)); + + // resize array + ecsResizeSystems(ecsSystems.size - 1); +} + +// +// TASKS +// + +void ecsPushTask(ecsTask task) +{ + if(ecsPushTaskStack()) + { + ecsTask* last = ecsTasks.begin + ecsTasks.size - 1; + memmove(last, &task, sizeof(ecsTask)); + } +} + +static inline void ecsRunTask(ecsTask task) +{ + switch(task.type) + { + default: return; + + case ECS_ENTITY_DESTROY: + ecsTaskDestroyEntity(task.entity); + return; + + case ECS_COMPONENTS_DETACH: + ecsTaskDetachComponents(task.entity, task.components.mask); + return; + + case ECS_SYSTEM_CREATE: + ecsTaskEnableSystem(task.system); + return; + case ECS_SYSTEM_DESTROY: + ecsTaskDisableSystem(task.system.fn); + return; + } +} + +void ecsRunTasks() +{ + for(size_t i = 0; i < ecsTasks.size; i++) + ecsRunTask(ecsTasks.begin[i]); + ecsClearTasks(); +} + +// +// FIND HELPERS +// + +static inline ECScomponentType* ecsFindComponentType(ecsComponentMask id) +{ + for(size_t i = 0; i < ecsComponents.size; ++i) + { + if(ecsComponents.begin[i].id == id) + return (ecsComponents.begin + i); + } + return NULL; +} + +void* ecsFindComponentFor(ECScomponentType* type, ecsEntityId id) +{ + if(type->size == 0) return NULL; + + BYTE* sptr; + ecsEntityId* eptr; + int l = 0; + int r = type->size - 1; + int m; + + while(l <= r) + { + m = round((double)(l+r)/2.f); + sptr = ((BYTE*)type->begin) + m * type->stride; // median element + eptr = sptr; + + // found the correct component + if(*eptr == id) + return sptr; + // go up + else if(*eptr < id) + l = m + 1; + // go down + else if(*eptr > id) + r = m - 1; + } + return NULL; +} + +static inline ECSentityData* ecsFindEntityData(ecsEntityId id) +{ + for(size_t i = 0; i < ecsEntities.size; ++i) + { + if(ecsEntities.begin[i].id == id) + return (ecsEntities.begin + i); + } + return NULL; +} + +static inline ECSsystem* ecsFindSystem(ecsSystemFn fn) +{ + for(size_t i = 0; i < ecsSystems.size; ++i) + { + if(ecsSystems.begin[i].fn == fn) + return (ecsSystems.begin + i); + } + return NULL; +} + +// +// RESIZE HELPERS +// + +static inline int ecsResizeSystems(size_t size) +{ + if(size == 0) + { + free(ecsSystems.begin); + ecsSystems.begin = NULL; + ecsSystems.size = 0; + } + else + { + ECSsystem* nptr = realloc(ecsSystems.begin, size * sizeof(ECSsystem)); + if(nptr == NULL) return 0; + + ecsSystems.size = size; + ecsSystems.begin = nptr; + } + return 1; +} + +static inline int ecsPushTaskStack() +{ + size_t size = ecsTasks.size + 1; + void* nptr = realloc(ecsTasks.begin, size * sizeof(ecsTask)); + if(nptr == NULL) return 0; + + ecsTasks.size = size; + ecsTasks.begin = nptr; + return 1; +} + +static inline void ecsClearTasks() +{ + if(ecsTasks.begin == NULL || ecsTasks.size == 0) return; // no tasks + + ecsTasks.size = 0; + free(ecsTasks.begin); + ecsTasks.begin = NULL; +} + +static inline int ecsResizeEntities(size_t size) +{ + if(size == 0) + { + free(ecsEntities.begin); + ecsEntities.begin = NULL; + ecsEntities.size = 0; + } + else + { + ECSentityData* nptr = realloc(ecsEntities.begin, size * sizeof(ECSentityData)); + if(nptr == NULL) return 0; + + ecsEntities.size = size; + ecsEntities.begin = nptr; + } + return 1; +} + +static inline int ecsResizeComponentType(ECScomponentType* type, size_t size) +{ + if(size == 0) + { + if (type->begin == NULL) return 1; + + free(type->begin); + type->begin = NULL; + type->size = 0; + } + else + { + void* nptr = realloc(type->begin, size * (type->stride)); + assert(nptr != NULL); + if(nptr == NULL) return 0; + + type->size = size; + type->begin = nptr; + } + return 1; +} + +static inline int ecsResizeComponents(size_t size) +{ + if(size == 0) + { + free(ecsComponents.begin); + ecsComponents.size = 0; + ecsComponents.begin = NULL; + } + else + { + ECScomponentType* nptr = realloc(ecsComponents.begin, size * sizeof(ECScomponentType)); + if(nptr == NULL) return 0; + + ecsComponents.begin = nptr; + ecsComponents.size = size; + } + return 1; +} diff --git a/ecs.h b/ecs.h new file mode 100644 index 0000000..543458d --- /dev/null +++ b/ecs.h @@ -0,0 +1,131 @@ +#ifndef ecs_h +#define ecs_h + +#include +#include +#include + + +#if __cplusplus +extern "C" { +#endif + +typedef unsigned long long ecsEntityId; +typedef unsigned long long ecsComponentMask; + +typedef void (*ecsSystemFn)(ecsEntityId*, ecsComponentMask*, size_t, float); + +#define noentity ((ecsEntityId)0x0) +#define nocomponent ((ecsComponentMask)0x0) +#define anycomponent ((ecsComponentMask)~0x0) + +typedef enum ECSqueryComparison { + ECS_NOQUERY = 0x0, + ECS_QUERY_ANY, + ECS_QUERY_ALL, +} ecsQueryComparison; + +typedef struct ecsComponentQuery { + ecsQueryComparison comparison; + ecsComponentMask mask; +} ecsComponentQuery; + +void ecsInit(void); + +/** + * \brief Allocates a component list for a component type of stride bytes. + * \param stride The number of bytes to allocate for each component. + */ +ecsComponentMask ecsMakeComponentType(size_t stride); +#define ecsRegisterComponent(__type) ecsMakeComponentType(sizeof(__type)) + +/** + * \brief Get a pointer to a component attached to entity. + * \param entity The entity to find a component of. + * \param component The component type to find. + * \returns A pointer to a component if found. + * \returns NULL if entity does not contain the given component. + */ +void* ecsGetComponentPtr(ecsEntityId entity, ecsComponentMask component); + +/** + * \brief Assigns a new entity id. + * \param components A component query referencing the components to add to the new object. + * \returns The id used to reference the newly created entity. + * \returns NULL if allocation failed + */ +ecsEntityId ecsCreateEntity(ecsComponentMask components); + +/** + * \brief Gets the component mask for an entity. + * \param entity the entity to get the mask for. + * \returns the ecsComponentMask for entity. + */ +ecsEntityId ecsGetComponentMask(ecsEntityId entity); + +/** + * \brief Checks if the argument is a valid entity id of a currently existing entity. + * \param entity The entity to check the validity of. + * \returns 1 if the entity exists, 0 otherwise. + */ +int ecsValidEntity(ecsEntityId entity); + +/** + * \brief Destroys an entity and all associated components + * \param entity The id of the entity to destroy. + */ +void ecsDestroyEntity(ecsEntityId entity); + +/** + * \brief Attaches one or more components. + * \param entity The entity to attach the new components to. + * \param components Bitmask of the componentId's to attach. + */ +void ecsAttachComponents(ecsEntityId entity, ecsComponentMask components); + +/** + * \brief Detaches one or more components. + * \param entity The entity to detach components from. + * \param components Bitmask of the components to detach. + */ +void ecsDetachComponents(ecsEntityId entity, ecsComponentMask components); + +/** + * \brief Enables a function to act as a system for entities matching the given query. + * \param func The function to call when query is met. + * \param components The required components to run this system. + * \param comparison The type of requirement components represent. one of { ECS_QUERY_ANY ; ECS_QUERY_ALL }. + * \note + * When comparison=ECS_QUERY_ALL the system will run only when all of the masked components are present on an entity. + * \note + * When comparison=ECS_QUERY_ANY the system will run for all entities where any of the masked components are present. + */ +void ecsEnableSystem(ecsSystemFn func, ecsComponentMask components, ecsQueryComparison comparison, int maxThreads, int executionOrder); + +/** + * \brief Disables a function acting as a system. + * \param func Pointer to the function to disable. + */ +void ecsDisableSystem(ecsSystemFn func); + +/** + * \brief Run currently enabled systems. + * \note Implicitly calls ecsRunTasks after completion. + */ +void ecsRunSystems(float deltaTime); + +/** + * \brief Run queued tasks. + */ +void ecsRunTasks(void); + +/** + * \brief Terminate the ECS and clean up allocated resources. + */ +void ecsTerminate(void); + +#if __cplusplus +} +#endif + +#endif /* ecs_h */