lowlines

Nitro Model Animation (NSBCA)

Category: Nintendo DS

Description: Common model animation format used in Nintendo DS games.

Author: lowlines

Filename: bca0.xml

Size: 5.15 KB

Date Modified: 07 November 2019

• Nitro 3D Header

  • Type		Offset	Size	Value	Description
    Magic Stamp		0x0000	4	0x42434130	Stamp (BCA0) "Basic Character Animation".
    Constant		0x0004	4	0x0001FEFF
    File Size		0x0008	4
    Header Size		0x000C	2	16
    # Sections		0x000E	2	1
    Section Offset		0x0010	4		Repeats * Number of Sections.

• Joint Section (JNT0)
  • Main Header

    • Type		Offset	Size	Value	Description
      Magic Stamp		0x0000	4	0x4A4E5430	Stamp (JNT0) "Joint Transformation".
      Section Size		0x0004	4

  • Object Header

    • Type		Offset	Size	Value	Description
      Dummy		0x0000	1	0
      # Objects		0x0001	1
      Header Size		0x0002	2
      Unknown Block
      Data Size		0x0000	2	8
      Block Size		0x0002	2
      Constant		0x0004	4	0x0000017F
      Unknown Data		0x0008	8		Repeats * Number of Objects.
      Offset Block
      Data Size		0x0000	2	4
      Block Size		0x0002	2
      Object Offset		0x0004	4		Offset to Data. Relative to start of this section. Repeats * Number of Objects.
      Name Block
      Object Name		0x0000	16		Repeats * Number of Objects.

  • Joint Animation Block (J.AC) - Repeats * Number of Objects

    • Type		Offset	Size	Value	Description
      Magic Stamp		0x0000	4	0x4A004143	Stamp (J.AC) "Joint Animation Content?".
      # Frames		0x0004	2
      # Objects		0x0006	2		Number of Objects being animated. Should equal to the number of Objects in a model.
      Unknown		0x0008	4
      Offset1		0x000C	4		Offset to Offset1 chunk. Relative to start of this block.
      Offset2		0x0010	4		Offset to Offset2 chunk. Relative to start of this block.
      Object Info Offset		0x0000	4		Repeats * Number of Objects. Relative to start of this block.
      Object Info - Repeats * Number of Objects
      Flag		0x0000	2		Indicates what sort of Transformations are applied. --zyx-Sr-RZYX-T- T, R, S stand for Translation, Rotation & Scale respectively. If they are cleared, transformation data follows. X, Y, Z, r, x, y, z are flags that identify how the data is stored.
      Unknown		0x0002	1
      ID #		0x0003	1
      Transformation Info (Translation XYZ, Rotation, Scale XYZ) when set
      Fixed Value		0x0000	4		Actual value.
      Transformation Info (Translation XYZ, Rotation, Scale XYZ) when cleared
      Unknown		0x0000	2		Typically 0.
      Unknown		0x0002	2
      Offset		0x0004	4		Offset to data. Relative to end Object Info Header (Object Info Offset + 4).

  • Offset1 Chunk - Repeats until Offset2

    • Type		Offset	Size	Value	Description
      Number		0x0000	2		I've seen 36, 32 & 0.
      Value1		0x0002	2		Possibly a signed value?
      Value2		0x0004	2		Possibly a signed value?

  • Offset2 Chunk - Repeats until end of file
    • All transformation offsets point somewhere in this section. It's clearly broken up into parts (Translation, Rotation & Scale) however I'm not totally sure how data is store in here yet.