Difference between revisions of "Breakable (RW Section)"

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m (Specified again the color format for ambientColors mentioned since earlier edits.)
m (Split magic number from header.)
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{{RW Section|Breakable model|0x0253F2FD}}
 
{{RW Section|Breakable model|0x0253F2FD}}
  
'''Breakable model''' is one of Rockstar's [[List of RW section IDs#Rockstar.27s_Custom_Sections|custom sections]] used in [[GTA San Andreas]]. It contains information on how to split breakable objects when they are hit. An object including this section has to be defined in [[object.dat]].
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'''Breakable model''', or simply '''Breakable''', is one of Rockstar's [[List of RW section IDs#Rockstar.27s_Custom_Sections|custom sections]] used in [[GTA San Andreas]]. It contains information on how to split breakable objects when they are hit. An object including this section has to be defined in [[object.dat]].
  
 
The typical location in a SA [[model file|dff]] section hierarchy is ''[[Clump (RW Section)|Clump]] > [[Geometry List (RW Section)|Geometry List]] > [[Geometry (RW Section)|Geometry]] > [[Extension (RW Section)|Extension]] > Breakable model.
 
The typical location in a SA [[model file|dff]] section hierarchy is ''[[Clump (RW Section)|Clump]] > [[Geometry List (RW Section)|Geometry List]] > [[Geometry (RW Section)|Geometry]] > [[Extension (RW Section)|Extension]] > Breakable model.
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==Magic number==
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The initial ''4 bytes'' sequence signals the usage of the extension:
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UINT32  magicNumber
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If zero, the section ends here. A non-zero value has no particular meaning and can be any (see [[Talk:Breakable_model_(RW_Section)#Meaningless values|Meaningless values]]).
  
 
==Header==
 
==Header==
  
There is a ''56 byte'' header which holds information about the amount of data arrays that follow:
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There is a ''52 byte'' header which holds information about the amount of data arrays that follow:
  
UINT32  magicNumber (zero if ''Breakable model'' is not used, otherwise any random non-zero value)
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  UINT32  posnRule (0 = OBJECT_ORIGIN, 1 = COLLISION_ORIGIN)
  UINT32  posnRule{{ref|posnrule|[*]}} (0 = OBJECT_ORIGIN, 1 = COLLISION_ORIGIN)
 
 
  // Vertex data
 
  // Vertex data
 
  UINT16  numVertices
 
  UINT16  numVertices
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  UINT32  (assumed offset to ambientColors, unused)
 
  UINT32  (assumed offset to ambientColors, unused)
  
;Note
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The position rule imposes whether to calculate the position relatively to the collision model or to the clump/atomic ''RwFrame''. See [[Talk:Breakable_model_(RW_Section)#Meaningless values|Meaningless values]] for clarifications about the unused fields.
:{{note|posnrule}} Impose whether to calculate the position relatively to the collision model or to the clump/atomic ''RwFrame''.
 
  
 
==Vertex data==
 
==Vertex data==

Revision as of 10:22, 22 June 2015

{{{NAME}}}
RenderWare Stream Section
Vendor {{{VENDORNAME}}}
Module {{{MODULENAME}}}
Module ID 0x{{{MODULEID}}}
Identifier 0x{{{IDENTIFIER}}}
Chunk ID 0x{{{MODULEID}}}{{{IDENTIFIER}}}
Versions All
Hierarchy
Parents:
None
Children:
None
Extensions:
None
File Format

Breakable model, or simply Breakable, is one of Rockstar's custom sections used in GTA San Andreas. It contains information on how to split breakable objects when they are hit. An object including this section has to be defined in object.dat.

The typical location in a SA dff section hierarchy is Clump > Geometry List > Geometry > Extension > Breakable model.

Magic number

The initial 4 bytes sequence signals the usage of the extension:

UINT32  magicNumber

If zero, the section ends here. A non-zero value has no particular meaning and can be any (see Meaningless values).

Header

There is a 52 byte header which holds information about the amount of data arrays that follow:

UINT32  posnRule (0 = OBJECT_ORIGIN, 1 = COLLISION_ORIGIN)
// Vertex data
UINT16  numVertices
UINT16  
UINT32  (assumed offset to verts, unused)
UINT32  (assumed offset to texCoords, unused)
UINT32  (assumed offset to preLitLum, unused)
// Triangle data
UINT16  numTriangles
UINT16  
UINT32  (assumed offset to vertIndices, unused)
UINT32  (assumed offset to matIndices, unused)
// Material data
UINT16  numMaterials
UINT16  
UINT32  (assumed offset to textures, unused)
UINT32  (assumed offset to textureNames, unused)
UINT32  (assumed offset to textureMasks, unused)
UINT32  (assumed offset to ambientColors, unused)

The position rule imposes whether to calculate the position relatively to the collision model or to the clump/atomic RwFrame. See Meaningless values for clarifications about the unused fields.

Vertex data

FLOAT[3]    verts[numVertices]
FLOAT[2]    texCoords[numVertices]
BYTE[4]     preLitLum[numVertices] (RGBA)

Triangle data

UINT16[3]   vertIndices[numTriangles]
UINT16      matIndices[numTriangles]

Material data

Each polygon group sharing the same material is treated as a separate fragment when the object is split up:

CHAR[32]    textureNames[numMaterials]
CHAR[32]    textureMasks[numMaterials]
FLOAT[3]    ambientColors[numMaterials] (RGB normalized in range [0,1])

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