Vertex transforms and camera space

A vertex program’s constant names do not uniquely determine its transform convention. Programs named alike can expect either absolute world positions or positions relative to the camera. Proven · executed vertex programs

View-projection

Executing a program with identity matrices and palettes, first at camera zero and then with a translated camera, distinguishes the two observed forms: VP * world and VP * (world-camera). The latter expects a view-projection matrix for a world whose origin is the camera. Proven · executed vertex programs

Among Elden Ring’s 15,707 inspected vertex programs whose clip position has matrix-times-world form, 15,483 are camera-relative and 224 are absolute. A VC_MatrixViewProj name therefore does not establish camera subtraction by itself. Proven · Elden Ring · executed vertex programs Of Sekiro’s 42 programs of that form, 41 are camera-relative and one is absolute. Proven · Sekiro · executed vertex programs

The execution does not classify a program that fails to return the supplied position under identity inputs or whose response to moving the camera fits neither form; no transform convention is established for that case. Unknown

Joint matrices

Every palette-applying vertex program in the bundle census reads each joint as three float4 rows, not columns: 17,455 Elden Ring programs and 42 Sekiro programs. One additional Elden Ring program reads only joint translations, so its accesses alone do not distinguish a complete matrix layout. Proven · whole-bundle palette census

Some Elden Ring skinned programs apply VC_aClothCancelObjMatrix (constant buffer cbClothCancelObjMatrix, register b12) before VC_aObjMatrix (cbObjMatrix, register b5), giving two distinct palettes. A vertex-indexed constant-buffer access distinguishes a joint palette from an instance-only object matrix. Observed · Elden Ring

only in Sekiro Sekiro’s skinned vertex programs declare no BLENDINDICES input: they take the joint index from NORMAL0.w, the integer W of the stored normal (nodes and skinning). Observed · Sekiro

Of Elden Ring’s 18,530 vertex programs in its four shader-bundle binders, 3,928 bind constant buffer register 12 (their runtime resource tables, read from every program): 2,972 name it cbClothCancelObjMatrix (2,520 in C[…] character bundles, 284 CS[…], 64 P[…], 56 M[…], 28 cutscene, 20 S[…]) and the 956 SpeedTree programs name it cbSpeedTree. Proven · Elden Ring · every vertex program, resource table and reflection In two disassembled programs, a skinned one and one taking a single joint per vertex (from the normal’s fourth lane), the vertex goes through the cloth-cancel matrix first and the object palette second, both at the same index, the instance’s matrix base plus the joint: Obj[i] * CC[i] * p for the position, and the 3 x 3 parts for the normal and tangent; the skinned one blends four joints’ cloth-cancel matrices by their weights, then four joints’ object matrices. Observed · Elden Ring In a captured frame, a skinned draw’s cloth-cancel buffer is bound as large as its object palette (512 to 12,288 bytes), and of 12,230 recorded entries 7,940 are not the identity (small rotations, translations of centimetres), 3,746 are and 544 are zero; many of the same draws’ object palette entries hold one matrix, the object’s. Observed · Elden Ring So the joint’s transform is split between the two palettes by the engine; which joints take which part is not established. Unknown

Sekiro’s programs declare the cloth-cancel palette only in parts_AMSN_clothmatcing, which applies it the same way. Observed · Sekiro

The runtime buffer extent can exceed the shader’s declared extent. The captured c3000 draws and their 256-matrix palette are described under nodes and skinning.

Census of the forms in use

Tracing the clip position (SV_Position) of every vertex program bound by the draws of ten Elden Ring frames (191 programs) back to the inputs it depends on, the programs fall into these forms. Observed · Elden Ring · 191 programs of ten captured frames

Form	Programs
Joint index from the normal’s W, object palette, camera-relative view-projection	78, plus 15 that add time or a force parameter, and 3 more that add a texture fetch
Skinned, object palette	23
Skinned, cloth-cancel then object palette	15
Joint from the normal’s W, cloth-cancel then object palette	7
Skinned or rigid with a world matrix (VC_World)	7
SpeedTree, wind constants added	11 (plus a billboard with view-projection only)
Clip position from the vertex, no matrix (full-screen)	13
Own matrix constants (volume and effect programs)	7
Clip position passed through as SV_Position input	6
No clip position in the program (a later stage writes it)	8

In six Sekiro frames (79 programs) the same trace gives: joint from the normal’s W, object palette, camera-relative view-projection 25; skinned, object palette 19; world matrix 9; full-screen 8; pass-through 7; own matrices 8; clip position written by a later stage 3. Observed · Sekiro · 79 programs of six captured frames In Elden Ring, 15 of the joint-from-normal programs add time, a force parameter or a texture fetch to the position (by name: grass, vegetation, sway, flag and bird programs). Observed · Elden Ring · 191 programs of ten captured frames

Which transform forms remain unclassified?

The camera-relative or absolute test of the previous section covers programs of matrix-times-world form; the census above adds the forms the draws of these frames use but does not rerun that test on them. The order in which the VC_World programs apply the world matrix and the palette, and which stage writes the clip position where the program has none, are not established, and programs not bound by these frames are not covered. Unknown