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Documentation Index

Fetch the complete documentation index at: https://mintlify.com/SMGCommunity/Petari/llms.txt

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JSystem is Nintendo’s internal C++ framework library, reused across a wide range of GameCube and Wii games. In Petari it provides the foundational infrastructure on top of which the Super Mario Galaxy 1 game layer is built: 3D model loading and rendering, an audio sequencer, heap and archive management, a particle system, math utilities, and a set of debug/utility modules. The JSystem code in this repository is sourced from the doldecomp/tp (Twilight Princess) and doldecomp/ogws (One Piece: Unlimited Adventure) decompilation projects.
JSystem headers and source files were contributed by the zeldaret/tp and doldecomp/ogws projects. Credit goes to those teams for their prior decompilation work.

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Subsystems

JSystem is organized into eleven top-level directories under src/JSystem/. Each directory corresponds to a self-contained subsystem with its own namespace and header tree.
Defines the low-level GX-backed rendering primitives used by the J3D pipeline: materials, TEV stages, texture coordinate generation, vertex descriptors, draw buffers, and the global J3DSys state object.Key source files: J3DMaterial.cpp, J3DTevs.cpp, J3DShape.cpp, J3DVertex.cpp, J3DSys.cpp
// Material factory — selects the appropriate color/texgen/tev block subclass
J3DColorBlock*  J3DMaterial::createColorBlock(u32 flags);
J3DTexGenBlock* J3DMaterial::createTexGenBlock(u32 flags);
J3DTevBlock*    J3DMaterial::createTevBlock(int tevStageNum);
Owns the high-level model objects (J3DModel, J3DModelData) and the skeletal animation system (J3DJoint, J3DJointTree, J3DAnimation). Also handles skin deformation (J3DSkinDeform) and the per-frame matrix buffer (J3DMtxBuffer).Key source files: J3DModel.cpp, J3DModelData.cpp, J3DAnimation.cpp, J3DJoint.cpp, J3DSkinDeform.cpp
Reads Nintendo’s binary model format (.bmd/.bdl) and animation formats (.bca, .bck, etc.) from memory and populates the J3D data structures. Factory classes handle versioned material formats.Key source files: J3DModelLoader.cpp, J3DAnmLoader.cpp, J3DMaterialFactory.cpp, J3DShapeFactory.cpp
Implements a 2D scene graph for HUD and overlay rendering using an orthographic projection. Panes, pictures, and screens mirror the Wii’s nw4r::lyt concepts but at a lower level.Key source files: J2DScreen.cpp, J2DPane.cpp, J2DPicture.cpp, J2DOrthoGraph.cpp
Provides the sequence-playback layer of the JSystem audio pipeline. JASSeqCtrl drives a JASSeqParser to step through MIDI-like sequence data tick-by-tick, dispatching events to JASTrack objects for sound synthesis.Key source files: JASSeqCtrl.cpp, JASSeqParser.cpp, JASSeqReader.cpp, JASTrack.cpp
The resource-management backbone of JSystem. JKRHeap and JKRExpHeap implement zone-based memory allocation. Archive classes (JKRArchive, JKRDvdArchive, JKRAramArchive, JKRMemArchive, JKRCompArchive) wrap different storage backends behind a unified file-lookup API. JKRThread wraps OS threads.Key source files: JKRHeap.cpp, JKRExpHeap.cpp, JKRDvdArchive.cpp, JKRDecomp.cpp, JKRThread.cpp
A data-driven particle system that reads .jpa resource files. JPAEmitterManager owns a pool of JPAEmitter instances; each emitter generates JPAParticle objects shaped by JPABaseShape, JPAExtraShape, JPADynamicsBlock, and JPAFieldBlock descriptors.Key source files: JPAEmitterManager.cpp, JPAEmitter.cpp, JPAParticle.cpp, JPAResourceLoader.cpp, JPAResourceManager.cpp
Scalar and trigonometric helpers used throughout JSystem. Includes a random-number generator and fixed-point trigonometry tables.Key source files: JMath.cpp, JMATrigonometric.cpp, random.cpp
Lightweight intrusive linked-list and hash-code utilities used as building blocks by other JSystem modules.Key source files: linklist.cpp, hashcode.cpp
Stream abstractions (JSUInputStream, JSUMemoryStream) and an intrusive doubly-linked list (JSUList) used for serialization and object management.Key source files: JSUInputStream.cpp, JSUMemoryStream.cpp, JSUList.cpp
Assertion and exception handlers, a debug console, font rendering, palette and texture helpers, and framebuffer (JUTXfb) management. Primarily used during development and in debug builds.Key source files: JUTAssert.cpp, JUTConsole.cpp, JUTFont.cpp, JUTTexture.cpp, JUTException.cpp

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Decompilation status

JSystem modules vary in completion. Some files — particularly in JKernel and J3DGraphBase — are fully matched to the original binary. Others, especially parts of JAudio2 and JParticle, contain non-matching stubs that are still under active work. Check decomp.dev/SMGCommunity/Petari for up-to-date per-file progress.

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