
아케이드 PriPara 게임을 구동하는 엔진의 리버스 엔지니어링
PriPara (내부명 Prineo)는 SynSophia에서 개발한 아케이드 리듬 게임입니다.
이 프로젝트의 목표는 아케이드 시리즈의 모델 포맷을 리버스 엔지니어링하여 독점 캐릭터를 Nintendo Switch의 최신 버전 게임으로 이식하는 것이었습니다.
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Noesis 애드온을 통해 암호화된 리소스에서 가져온 스킨 모델

PriPara 아케이드에서 NintendoSwitch 버전으로 이식된 드레스, Noesis 플러그인을 사용하여 내보낸 모델
이 게임은 표준 암호화 프리미티브의 수정된 버전을 구현합니다.
Implementation: https://github.com/ExIfDev/Prineo_RE/blob/main/Noesis/fmt_prineo.py#L1130-L1140
Implementation: https://github.com/ExIfDev/Prineo_RE/blob/main/Noesis/fmt_prineo.py#L1074-L1128
다음 문서는 SSZL 압축 해제 후의 파일을 참조합니다.
const byte[] ident = {0x00, 0x13, 0x10, 0x09};
struct Header
{
uint32 VERSION;//1
uint32 FILE_SIZE;
byte[4] Ident;
int32 unk1;
int32 unk2;
int32 unk3;
uint32 DATA_OFFSET; //absolute offset
uint32 DATA_SIZE;
};
//the MDJ file can contain a variety of buffers related to geometry and scenes, it does
//not have a header, its assumed to start with one of the following buffers
//and always terminate with the "end/0/" marker
struct Pose //pose applied to a skeleton (=restPose in a model container)
//usually this pose is the same as in the "base" buffer.
//if AnimParams are present then what follows is the animation curves.
//AnimParams can be null when there are no keyframes.
{
char[4] ident = "pose";
uint16 strLen;
char[strLen] POSE_NAME;
byte[2] unk;
uint16 BONE_COUNT;
byte[8] unkdata;
struct Bone[BONE_COUNT]
{
uint16 serializer_id;//518
uint16 strLen;
string[strLen] BONE_NAME;
//Base transform
float sclX, sclY, sclZ;
float rotX, rotY, rotZ;
float tslX, tslY, tslZ;
//for all channels (9) "Sx", "Sy", "Sz", "Rx", "Ry", "Rz", "Tx", "Ty", "Tz"
struct AnimationParams //6 bytes
{
uint16 unk2; //possibly an uint32 since unk3 is always 0
uint16 unk3;
uint16 CHANNEL_MASK;
};
//if anim params are not null then....
uint32 KEYFRAME_COUNT;
struct Keyframe[KEYFRAME_COUNT]
{
float VALUE;//radians
float TIME;//centiseconds
}:
};
};
struct TextureDefs //define texture name and id bindings
{
string[4] ident ="imag";
uint16 TEX_COUNT;
struct TexDef[TEX_COUNT]
{
uint16 serializer_id;//1029
uint16 unk;
uint16 TEX_ID;
uint16 strLen;
string[strLen] texName;
};
};
struct MaterialChunk //defines parameters of materials and shaders
{
string[4] ident ="mate";
uint16 MAT_COUNT;
struct Material[MAT_COUNT]
{
uint16 serializer_id;//1024
uint16 strLen;
string[strLen] MatName;
uint32 TYPE;//..maybe hash? looked up in a registry
//Texture slots
//ambient
uint16 aCount;
for (int i = 0; i < aCount; i++)
{
uint16 serializer_id;
if (serializer_id == 1029)
{
uint32 unk;
}
else
{
uint32 unk2;
}
}
//diffuse
uint16 dCount;
for (int i = 0; i < dCount; i++)
{
uint16 serializer_id;
if (serializer_id == 1029)
{
uint32 unk;
}
else
{
uint32 unk2;
}
}
//specular
uint16 sCount;
for (int i = 0; i < sCount; i++)
{
uint16 serializer_id;
if (serializer_id == 1029)
{
uint32 unk;
}
else
{
uint32 unk2;
}
}
//possibly parameter slots
uint16 unk1Count;
for (int i = 0; i < unk1Count; i++)
{
uint16 serializer_id;
float unk12;
}
uint16 unk2Count;
for (int i = 0; i < unk2Count; i++)
{
uint16 serializer_id;
float unk22;
}
byte HAS_TEXTURE;
if (HAS_TEXTURE == 1)
{
uint16 TEX_COUNT;
struct TexureMap[TEX_COUNT]
{
uint16 serializer_id;
uint32 TEX_ID;
}
}
uint16 strLen;
string[strLen] unkNullString;
};
//two possible chunks could follow:
struct MPSS_Subchunk //clear usage unknown
{
string header = "MPSS";
uint16 count;
struct MPSS_Entry[count]
{
uint16 unk32;
byte[16] payload;
}
}
struct MPDS_Subchunk //string to value shader parameter chunk
{
string header = "MPDS";
uint16 count;
struct MPDS_Entry[count]
{
uint16 strLen;
string[strLen] Name;
byte[32] value;
}
}
};
struct LightChunk //defines parameters of lights in a scene
{
char[4] ident = "ligh";
int16 LIGHT_COUNT;
struct light[LIGHT_COUNT]
{
uint16 serializer_id;
uint16 strLen;
char[strLen] light_name;
byte[49] unk40; //transform matrix along with color vals
}
}
struct ModeBuffer//marks the start of a submesh list and its buffers
{
char[4] ident = "mode";
uint16 serializer_id;//513
uint16 strLen;
char[strLen] unkName; //possibly the root node
byte[4] unk;
uint16 unkC;
};
struct MeshMeta//a submesh starts with some metadata about its bounding size,name, and its boneMap
{
uint16 serializer_id;//770 0x0302
uint16 strLen;
char[strLen] MESH_NAME;
byte[4] unk;
uint16 boneMapCount;
struct HashedBoneMap[boneMapCount]
{
uint32 boneHash;//SSFNV1a hashed bone name
}
float unk3;
byte unk2;
byte[24] AABB;
}
struct MeshBegin //indicates the beginning of a submesh
{
string[4] ident ="verb";
};
struct FaceBuffer
{
string[4] ident = "surf";
int16 FACE_COUNT;
struct Face [FACE_COUNT]//stride: 6 //type: triangle list // winding:clockwise
{
uint16 A;
uint16 B;
uint16 C;
};
};
struct VertexBuffer
{
string[4] ident = "coor";
uint16 VERTEX_COUNT;
struct Vertex [VERTEX_COUNT] //stride 12
{
float x;
float y;
float z;
};
};
struct NormalBuffer
{
string[4] ident ="norm";
uint16 NORM_COUNT; //should be the same as VERTEX_COUNT
struct Normal[NORM_COUNT]//stride 12
{
float nx;
float ny;
float nz;
};
};
struct BinormalBuffer//binormal buffer (not present in any file)
{
string[4] ident ="bino";
uint16 BINO_COUNT; //should be the same as VERTEX_COUNT
struct BiNormal[NORM_COUNT]//stride 12
{
float bx;
float by;
float bz;
};
};
struct UV0Buffer
{
string[4] ident ="tex0";
uint16 UV0_COUNT; //should be the same as VERTEX_COUNT
struct UV[UV0_COUNT] //stride 8
{
float u;
float v;
};
};
struct UV1Buffer
{
string[4] ident ="tex1";
uint16 UV1_COUNT; //should be the same as VERTEX_COUNT
struct UV[UV1_COUNT] //stride 8
{
float u;
float v;
};
};
struct VertexColors
{
string[4] ident = "colo";
uint16 VERTEX_COUNT; //should be the same as VERTEX_COUNT
struct UV[UV1_COUNT] //stride 4
{
byte r,g,b,a;
};
}
struct TangentBuffer //signless tangent vector
{
char[4] ident ="tan ";
uint16 TANG_COUNT; //should be the same as VERTEX_COUNT
struct Tang[TANG_COUNT]//stride 12
{
float tx;
float ty;
float tz;
};
};
struct WeightBuffer //Weight values for each bone assigned to a vertex
{
char[4] ident ="weig";
uint16 WEIGHT_COUNT;
struct VertexWeight[WEIGHT_COUNT] //stride 16
{
float w1;
float w2;
float w3;
float w4;
};
};
struct VBIBuffer //Vertex Bone Index, in order, bone indices that influence a vertex
//this table is local to the current vertex buffer
{
char[4] ident ="bone";
uint16 VERTEX_COUNT;
struct VBI[VERTEX_COUNT]
{
byte boneIDX1;
byte boneIDX2;
byte boneIDX3;
byte boneIDX4;
};
};
//
struct Skeleton //Bone Node Tree, defines the bone relationships
{
char[4] ident ="skel";
struct BoneName[BONE_COUNT] //Bone count read from POSE chunk
{
uint16 serializer_id; //257=root 258=child
uint16 strLen;
char[strLen] BONE_NAME;
uint32 unk2;
uint16 CHILD_COUNT;
};
};
struct RestPose //defines the rest pose of the skeleton
{
char[4] ident ="base";
uint16 strLen;
char[strLen] POSE_NAME;
int16 BONE_COUNT;
struct BoneTrs[BONE_COUNT]
{
uint16 serializer_id;//1537
uint16 strLen;
char[strLen] BONE_NAME;
float sx, sy, sz; //scale
float rx, ry, rz; //rotation
float tx, ty, tz; //translation
};
};
struct MeshEnd //indicates the end of a mesh
{
string[4] ident ="vere";
uint16 strLen;
char[strLen] NAME;
byte[2] padding;
};
struct EndFlag //indicates the end of the file
{
string[4] ident ="end "
}
//information is related to the decompressed file
struct Header
{
uint32 VERSION;
uint32 FILE_SIZE;
uint32 tex_ident;
uint32 unk;
uint32 TEXTURE_COUNT;
};
struct TextureDecl[TEXTURE_COUNT]
{
uint32 HASH;//hashed texture name minus the extension
uint32 OFFSET;//absolute offset
uint32 SIZE;
};
//follows texture buffers at OFFSET with SIZE
//TGA or DDS