DKRDS Track (File Format) - Revision history

Atlas: /* Triangle Entry */

2026-06-18T18:39:27Z

Triangle Entry

@@ Line 219: / Line 219: @@
 | 0x00 || UInt16 || '''Attribute flags'''. '''AAAA AAAA AAAA AAAB''':
 * '''A''': '''Texture ID'''.
-* '''B''': Collidable attribute? If 0 in roads, the triangles are not collidable. Unknown meaning in walls.
+* '''B''': '''Dominant normal direction sign''' used for collision detection. Calculated in the following way:
 |-
 | 0x02 || UInt16[3] || '''Face XYZ normals'''. Values need to be divided by 4096.

Atlas: /* Track Section Entry */

2026-06-16T23:50:35Z

Track Section Entry

← Older revision		Revision as of 23:50, 16 June 2026
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	! Offset !! Type !! Description		! Offset !! Type !! Description
	\|-		\|-
	\| 0x00 \|\| Byte \|~~\| {{unknown-left~~\|'''~~Unknown~~'''.}}		\| 0x00 \|\| Byte \|\| '''Main collision attribute mask'''. This is an OR of all of the main collision attribute values for all polygon groups in this section.
	\|-		\|-
	\| 0x01 \|\| Byte \|~~\| {{unknown-left~~\|'''~~Unknown~~'''.}}		\| 0x01 \|\| Byte \|\| '''Secondary collision attribute mask'''. This is an OR of all of the secondary collision attribute values for all polygon groups in this section.
	\|-		\|-
	\| 0x02 \|\| UInt16 \|~~\| {{unknown-left~~\|'''~~Unknown~~'''.}}		\| 0x02 \|\| UInt16 \|\| '''Tertiary collision attribute mask'''. This is an OR of all of the tertiary collision attribute values for all polygon groups in this section.
	\|-		\|-
	\| 0x04 \|\| UInt16 \|\| '''Number of polygon groups''' ('''P''').		\| 0x04 \|\| UInt16 \|\| '''Number of polygon groups''' ('''P''').

Atlas: /* Wish Race Unknown Section */

2026-06-16T18:29:30Z

Wish Race Unknown Section

← Older revision		Revision as of 18:29, 16 June 2026
Line 423:		Line 423:

	== Wish Race Unknown Section ==		== Wish Race Unknown Section ==
	This section is only used for the Wish Race tracks. ''TBD''		This section is only used for the Wish Race tracks. Each entry is 0x18 bytes long. ''TBD''

	= Tools =		= Tools =

Atlas: /* Track Section Entry */

2026-06-15T20:15:15Z

Track Section Entry

← Older revision		Revision as of 20:15, 15 June 2026
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	=== Track Section Entry ===		=== Track Section Entry ===
	Every section entry defines model and collision data. The entry starts with a 32-byte header.		Every section entry defines model and collision data. The entry starts with a 32-byte header. All offsets are relative to the start of this entry.

	{\|class=wikitable		{\|class=wikitable

Atlas: /* Track Section Entry */

2026-06-15T19:52:35Z

Track Section Entry

← Older revision		Revision as of 19:52, 15 June 2026
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	\| 0x00 \|\| Byte \|\| {{unknown-left\|'''Unknown'''.}}		\| 0x00 \|\| Byte \|\| {{unknown-left\|'''Unknown'''.}}
	\|-		\|-
	\| 0x01 \|\| Byte \|\| {{unknown-left\|'''Unknown'''. ~~Always 5?~~}}		\| 0x01 \|\| Byte \|\| {{unknown-left\|'''Unknown'''.}}
	\|-		\|-
	\| 0x02 \|\| UInt16 \|\| {{unknown-left\|'''Unknown'''.}}		\| 0x02 \|\| UInt16 \|\| {{unknown-left\|'''Unknown'''.}}
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	\| 0x06 \|\| UInt16 \|\| '''Number of vertices''' in [[#Track Section Vertex Data\|Track Section Vertex Data]] ('''V''').		\| 0x06 \|\| UInt16 \|\| '''Number of vertices''' in [[#Track Section Vertex Data\|Track Section Vertex Data]] ('''V''').
	\|-		\|-
	\| 0x08 \|\| UInt16 \|\| '''Number of UVs''' in [[#Track Section UV\|Track Section UV Data]] ('''U''').		\| 0x08 \|\| UInt16 \|\| '''Number of UVs''' in [[#Track Section UV Data\|Track Section UV Data]] ('''U''').
	\|-		\|-
	\| 0x0A \|\| UInt16 \|\| '''Number of colors''' in [[#Track Section Color Data\|Track Section Color Data]] ('''C''').		\| 0x0A \|\| UInt16 \|\| '''Number of colors''' in [[#Track Section Color Data\|Track Section Color Data]] ('''C''').

Atlas at 19:03, 15 June 2026

2026-06-15T19:03:59Z

← Older revision		Revision as of 19:03, 15 June 2026
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	\| 0x04 \|\| Int32 \|\| '''[[#Track Section Group\|Track Section Group]]''' offset.		\| 0x04 \|\| Int32 \|\| '''[[#Track Section Group\|Track Section Group]]''' offset.
	\|-		\|-
	\| 0x08 \|\| Int32 \|\| '''[[#~~Collision~~ Effects\|~~Collision~~ Effects]]''' offset.		\| 0x08 \|\| Int32 \|\| '''[[#Terrain Effects\|Terrain Effects]]''' offset.
	\|-		\|-
	\| 0x0C \|\| Byte[4] \|\| {{unknown-left\|'''Unknown'''. Always 0xCCCCCCCC.}}		\| 0x0C \|\| Byte[4] \|\| {{unknown-left\|'''Unknown'''. Always 0xCCCCCCCC.}}
Line 334:		Line 334:
	\|}		\|}

	== ~~Collision~~ Effects ==		== Terrain Effects ==
	Each texture is linked to 2 specific ~~collision~~ effects that affect the vehicle's speed, particles and lighting. This section contains 2 blocks of '''X''' UInt16s.		Each texture is linked to 2 specific terrain effects that affect the vehicle's speed, particles and lighting. This section contains 2 blocks of '''X''' UInt16s.

	{\|class=wikitable		{\|class=wikitable

Atlas: /* Culling BSP Tree */

2026-06-15T10:37:14Z

Culling BSP Tree

← Older revision		Revision as of 10:37, 15 June 2026
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	* '''2''' = Z axis.		* '''2''' = Z axis.
	\|-		\|-
	\| 0x02 \|\| Int16 \|\| '''Split value ~~low~~ bits'''.		\| 0x02 \|\| Int16 \|\| '''Split value high bits'''.
	\|-		\|-
	\| 0x04 \|\| UInt16 \|\| '''Split value ~~high~~ bits'''.		\| 0x04 \|\| UInt16 \|\| '''Split value low bits'''.
	\|-		\|-
	\| 0x06 \|\| Int16 \|\| '''Skip count'''. The right child begins at <code>(node_offset + 8) + skip * 2</code> bytes from the start of this section. The left child begins immediately at <code>node_offset + 8</code>.		\| 0x06 \|\| Int16 \|\| '''Skip count'''. The right child begins at <code>(node_offset + 8) + skip * 2</code> bytes from the start of this section. The left child begins immediately at <code>node_offset + 8</code>.
	\|}		\|}

	The split coordinate ~~in world units~~ is reconstructed by the game as a 32-bit signed result:		The split coordinate is reconstructed by the game as a 32-bit signed result, then divided by 64 to obtain the coordinates in world units (the same scale as the [[#Track Section AABB\|section AABBs]]):
	<pre>		<pre>
	split = (~~split_low~~ << 10) \| ~~split_high~~		split = ((split_high << 16) \| (split_low & 0xFFFF)) / 64
	</pre>		</pre>

	To encode a world-coordinate integer back into the two stored fields:		To encode a world-coordinate integer back into the two stored fields:
	<pre>		<pre>
	(Int16)~~split_low~~ = ~~split~~ >> 10		split_raw = round(split * 64)
	(UInt16)~~split_high~~ = ~~split~~ & 0xFFFF		(Int16)split_high = (split_raw >> 16) & 0xFFFF
			(UInt16)split_low = split_raw & 0xFFFF
	</pre>		</pre>

	~~The split values are in the same coordinate scale as the [[#Track Section AABB\|section AABBs]], divided by 64.~~

	The stored ''split_high'' in original game files often differs from the canonical <code>split & 0xFFFF</code> decomposition. The extra bits in positions 10-15 of ''split_high'' are ORed with bits already set by the sign extension of ''split_low'' and therefore have no effect on the reconstructed split. Their origin is unknown.

	=== Leaf Node ===		=== Leaf Node ===
Line 409:		Line 406:
	* '''track_sg''': pointer to the [[#Track Section Group\|Track Section Group]].		* '''track_sg''': pointer to the [[#Track Section Group\|Track Section Group]].
	* '''position''': player XYZ position.		* '''position''': player XYZ position.
	* '''tolerance''': a proximity radius ~~in world units~~, observed as <code>0xF00</code>.		* '''tolerance''': a proximity radius, observed as <code>0xF00</code> (60 in world units).
	* '''out_list''': output structure that receives the active section list.		* '''out_list''': output structure that receives the active section list.

	At each interior node:		At each interior node, in world-unit scale:
	<pre>		<pre>
	pos = position[axis]		pos = position[axis]
	~~split~~ = (~~split_low~~ << 10) \| ~~split_high~~		split_raw = (split_high << 16) \| (split_low & 0xFFFF)
			split = split_raw / 64
	</pre>		</pre>

	If <code>split - pos > tolerance</code>, visit left child only; else if <code>pos - split ≥ tolerance</code>, visit right child only; otherwise, visit both ~~cildren~~.		If <code>split - pos > tolerance</code>, visit the left child only; else if <code>pos - split ≥ tolerance</code>, visit the right child only; otherwise, visit both children.

			The left child corresponds to sections whose AABB satisfies <code>min[axis] ≤ split</code>; the right child corresponds to sections whose AABB satisfies <code>max[axis] ≥ split</code>. Sections satisfying both (i.e. whose AABB traverses the split plane) appear in leaves on both sides.

	At each leaf node, for every listed section ID the section's data pointer is first looked up via the [[#Track Section Group\|Track Section Group]]. Then, the player's bounding box is tested (<code>(X ± tolerance) * (Z ± tolerance)</code>) against the section's [[#Track Section AABB\|AABB]]. If the AABB test passes, add the section to the active render list.		At each leaf node, for every listed section ID the section's data pointer is first looked up via the [[#Track Section Group\|Track Section Group]]. Then, the player's bounding box is tested (<code>(X ± tolerance) * (Z ± tolerance)</code>) against the section's [[#Track Section AABB\|AABB]]. If the AABB test passes, add the section to the active render list.

Atlas at 22:03, 12 June 2026

2026-06-12T22:03:16Z

@@ Line 1: / Line 1: @@
 '''DKRDS Track''' is the nameless file format used in ''[https://en.wikipedia.org/wiki/Diddy_Kong_Racing_DS Diddy Kong Racing DS]'' that stores the tracks' section models, collision and textures. Its type identifier in [[assets.bin]] is '''0x9A'''.
@@ Line 277: / Line 276: @@
+     {
          int cell = Math.Max(0, Math.Min(nrCells - 1, (int)MathF.Floor(faceMin)));
-         bool atExact  = MathF.Abs(faceMin - MathF.Round(faceMin)) < Epsilon;
+         bool atExact = MathF.Abs(faceMin - MathF.Round(faceMin)) < Epsilon;
          bool atMaxEdge = cell == nrCells - 1;
@@ Line 359: / Line 358: @@
 == Culling BSP Tree ==
-''TBD''
+This section defines a serialized axis-aligned binary space partitioning tree used for culling sections along with the [[#Culling Groups|Culling Groups]] section. The game traverses it to determine which sections are candidates for rendering given the current player's position, and then performs a secondary [[#Track Section AABB|AABB]] overlap test on each candidate before adding it to the active render list. The section consists of a sequence of variable-length nodes and leaves stored one after another.
 == Wish Race Unknown Section ==

Atlas at 21:15, 12 June 2026

2026-06-12T21:15:32Z

@@ Line 29: / Line 29: @@
 | 0x1C || Int32 || '''[[#Texture Group|Texture Group]]''' offset.
 |-
-| 0x20 || Int32 || '''[[#Unknown Section 1|Unknown Section 1]]''' offset.
+| 0x20 || Int32 || '''[[#Culling BSP Tree|Culling BSP Tree]]''' offset.
 |-
 | 0x24 || Int32 || '''[[#Wish Race Unknown Section|Wish Race Unknown Section]]''' entry count.
@@ Line 198: / Line 198: @@
 |}
 |-
-| 0x08 || Byte[4] || {{unknown-left|'''Unknown'''.}}
+| 0x08 || Byte[4] || '''Collision grid mask'''. This is an OR of all of the [[#Track Section Collision Data|collision grids]] for all triangles in this group.
 |}
@@ Line 220: / Line 220: @@
 | 0x00 || UInt16 || '''Attribute flags'''. '''AAAA AAAA AAAA AAAB''':
 * '''A''': '''Texture ID'''.
-* '''B''': '''Is collidable'''.
+* '''B''': Collidable attribute? If 0 in roads, the triangles are not collidable. Unknown meaning in walls.
 |-
 | 0x02 || UInt16[3] || '''Face XYZ normals'''. Values need to be divided by 4096.
@@ Line 232: / Line 232: @@
 ===== Track Section Collision Data =====
--byte data per triangle (?). ''TBD''
+Each triangle corresponds to a 4-byte set of values to help with collision detection. These values encode local X, Y and Z coordinates that form a grid of cells inside the section's AABB.
 ===== Track Section Vertex Data =====
@@ Line 284: / Line 358: @@
 See '''[[DKRDS Texture Group]]'''.
-== Unknown Section 1 ==
+== Culling BSP Tree ==
 ''TBD''

Atlas: /* Polygon Group Entry */

2026-06-04T14:38:04Z

Polygon Group Entry

← Older revision		Revision as of 14:38, 4 June 2026
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	\| 0x01 \|\| Road and effects.		\| 0x01 \|\| Road and effects.
	\|-		\|-
	\| 0x05 \|\| Wall.		\| 0x05 \|\| Wall (sparks on collision).
	\|-		\|-
	\| 0x08 \|\| Special effects?		\| 0x08 \|\| Special effects (turns off visual model).
	\|-		\|-
	\| 0x0C \|\| Invisible wall.		\| 0x0C \|\| Invisible wall (no sparks on collision, turns off visual model).
	\|}		\|}
	\|-		\|-
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	{\| class="wikitable"		{\| class="wikitable"
	! ID !! Description		! ID !! Description
			\|-
			\| 0x00 \|\| Invisible wall (no sparks on collision).
	\|-		\|-
	\| 0x01 \|\| Water.		\| 0x01 \|\| Water.
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	\|-		\|-
	\| 0x20 \|\| {{unknown-left\|'''Unknown'''. Used in non-collideable stuff.}}		\| 0x20 \|\| {{unknown-left\|'''Unknown'''. Used in non-collideable stuff.}}
			\|-
			\| 0x60 \|\| {{unknown-left\|'''Unknown'''. Used in non-collideable stuff.}}
			\|}
			* '''Main flag = 0x08''':
			{\| class="wikitable"
			! ID !! Description
			\|-
			\| 0x30 \|\| {{unknown-left\|'''Unknown'''. Used in non-collideable stuff.}}
	\|}		\|}
	* '''Main flag = 0x0C''':		* '''Main flag = 0x0C''':