add bullet dependency first pass

2 files changed, 49 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3b18024..df4fe1b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -143,6 +143,32 @@ FetchContent_Declare(cgltf URL https://github.com/jkuhlmann/cgltf/archive/271614
 FetchContent_MakeAvailable(cgltf)
 target_include_directories(pke PUBLIC "${PROJECT_BINARY_DIR}/_deps/cgltf-src")
 
+FetchContent_Declare(bullet
+	GIT_REPOSITORY    https://github.com/bulletphysics/bullet3.git
+	GIT_TAG           3.25
+	OVERRIDE_FIND_PACKAGE
+)
+FetchContent_GetProperties(bullet)
+if(NOT bullet_POPULATED)
+	set(BUILD_SHARED_LIBS 1 CACHE STRING "" FORCE)
+	set(BUILD_BULLET2_DEMOS 0 CACHE STRING "" FORCE)
+	set(BUILD_CPU_DEMOS 0 CACHE STRING "" FORCE)
+	set(BUILD_UNIT_TESTS 0 CACHE STRING "" FORCE)
+	set(BUILD_OPENGL3_DEMOS 0 CACHE STRING "" FORCE)
+	set(BUILD_EXTRAS 0 CACHE STRING "" FORCE)
+	set(INSTALL_EXTRA_LIBS 0 CACHE STRING "" FORCE)
+	set(INSTALL_LIBS 0 CACHE STRING "" FORCE)
+	set(POSITION_INDEPENDENT_CODE O CACHE BOOL "" FORCE)
+	FetchContent_Populate(bullet)
+	add_subdirectory(${bullet_SOURCE_DIR} ${bullet_BINARY_DIR})
+	target_include_directories(pke PUBLIC BEFORE ${bullet_SOURCE_DIR}/src)
+	target_link_libraries(pke PUBLIC BulletDynamics BulletCollision LinearMath OpenGLWindow Bullet3Common)
+	message(STATUS "Bullet vars: " ${bullet_SOURCE_DIR} " - " ${bullet_BINARY_DIR})
+endif()
+find_package(Bullet REQUIRED
+	PATHS ${Bullet_SOURCE_DIR} ${Bullet_BINARY_DIR}
+)
+
 target_include_directories(pke PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/src")
 
 target_link_libraries(pke PUBLIC imguidocked)
diff --git a/src/ecs.cpp b/src/ecs.cpp
index b4207f8..17c5a89 100644
--- a/src/ecs.cpp
+++ b/src/ecs.cpp
@@ -1,9 +1,12 @@
 
 #include "ecs.hpp"
 
+#include "memory.hpp"
 #include "vendor/glm_include.hpp"
 #include "window.hpp"
 
+#include <btBulletDynamicsCommon.h>
+
 TypeSafeInt_B(EntityHandle);
 const uint64_t maxBucketItemCount = 256;
 
@@ -28,6 +31,13 @@ BucketContainer<EntityBucket, EntityHandle_T> Entities_BucketContainer{};
 BucketContainer<GrBindsBucket, GrBindsHandle_T> Comp_GrBinds_BucketContainer{};
 BucketContainer<InstanceBucket, InstanceHandle_T> Comp_Instance_BucketContainer{};
 
+MemBucket *bulletBucket = nullptr;
+btDefaultCollisionConfiguration *btConfiguration = nullptr;
+btCollisionDispatcher *btDispatcher = nullptr;
+btBroadphaseInterface *btBroadphase = nullptr;
+btConstraintSolver *btSolver = nullptr;
+btDiscreteDynamicsWorld *btDynamicsWorld = nullptr;
+
 void ECS_GetEntity_Inner(EntityHandle entHandle, Entity*& ent) {
 	EntityHandle_T entHandle_t{static_cast<EntityHandle_T>(entHandle)};
 	assert(entHandle_t != EntityHandle_T_MAX && "Unknown entity handle");
@@ -40,6 +50,18 @@ void ECS_Init() {
 	Buckets_Init(Entities_BucketContainer);
 	Buckets_Init(Comp_GrBinds_BucketContainer);
 	Buckets_Init(Comp_Instance_BucketContainer);
+	// bullet
+	{
+		bulletBucket = Pke_BeginTransientBucket();
+		btConfiguration = Pke_New<btDefaultCollisionConfiguration>(bulletBucket);
+		btDispatcher = Pke_New<btCollisionDispatcher>(bulletBucket);
+		new (btDispatcher) btCollisionDispatcher(btConfiguration);
+		btBroadphase = Pke_New<btDbvtBroadphase>(bulletBucket);
+		btSolver = Pke_New<btSequentialImpulseConstraintSolver>(bulletBucket);
+		btDynamicsWorld = Pke_New<btDiscreteDynamicsWorld>(bulletBucket);
+		new (btDynamicsWorld) btDiscreteDynamicsWorld(btDispatcher, btBroadphase, btSolver, btConfiguration);
+		btDynamicsWorld->setGravity(btVector3(0, -1, 0));
+	}
 }
 
 uint64_t ECS_GetEntities_BucketCount() {
@@ -401,6 +423,7 @@ CompInstance *ECS_GetInstances(uint64_t bucketIndex, uint64_t &itemCount) {
 }
 
 void ECS_Teardown() {
+	Pke_EndTransientBucket(bulletBucket);
 	EntitiesWithExcessInstances.~DynArray();
 	entitiesYetToBeRemoved.~DynArray();
 	EntitiesToBeRemoved.~DynArray();