ed/pikuma_ps1
1
0
Fork 0
mirror of https://github.com/Ed94/pikuma_ps1.git synced 2026-08-14 11:38:14 +00:00
Code Issues Packages Projects Releases Wiki Activity

Prepping for: resolve_look_at impl.

Browse Source
This commit is contained in:
ed
2026-08-08 23:13:18 -04:00
parent b045856dd6
commit 69f2c0d036
11 changed files with 164 additions and 75 deletions
Download Patch File Download Diff File Expand all files Collapse all files
code/hello_camera/gen/offsets.h
+1 -1
View File
@@ -26,7 +26,7 @@ enum {
atom_offset_end_low_exit_stick = _atom_offset_end_low_exit_stick,
};
// --- atom: pad_input_cam (41 words) ---
// --- atom: pad_input_cam (40 words) ---
#define _atom_offset_left_x_exit_left_x 3
#define _atom_offset_right_x_exit_right_x 3
code/hello_camera/hello_camera.atom.c
+37 -28
View File
@@ -180,26 +180,6 @@ internal MipsAtom_(gp_screen_init) atom_info(atom_phase(screen_init), atom_reads
mac_yield(),
};
/* ----- pad_apply_input -----
* Reads pad[0].buttons + pad[0].left_x;
* Applies the input-semantics deltas to cube_rot.y + floor_rot.y:
* - D-pad Left: cube_rot.y += 30, floor_rot.y += 5
* - D-pad Right: cube_rot.y -= 30, floor_rot.y -= 5
* - Analog stick X (dead zone 0x70..0x90):
* cube delta = (0x80 - left_x) >> 2 (range approx -32..+32)
* floor delta = (0x80 - left_x) >> 5 (range approx -4..+4)
* - D-pad + analog deltas add when used together.
*
* Convention:
* pad_state = 0 means no buttons active.
* The fail-safe zero-button value flows through unchanged, so a disconnected/fresh pad produces no rotation.
* The branch_le_zero pattern below matches the existing pad_input_demo convention (atom body lines 248/257).
*
* Signed-delta trick:
* load_byte_u zero-extends left_x to 32 bits; sub_u from 0x80 wraps to a SIGNED two's-complement value in the negative range;
* shift_aright (sra) then correctly sign-extends the shift for both positive (left_x < 0x80) and negative (left_x > 0x80) cases.
* Digital pads publish left_x = 0x80 → delta = 0 → no rotation, so the analog step is naturally a no-op for digital controllers.
*/
typedef Struct_(Binds_PadApplyInput) {
PadState* state;
V3_S2* cube_rot;
@@ -334,10 +314,9 @@ internal MipsAtom_(pad_input_cam) atom_info(atom_bind(Binds_PadInputCam)
load_word(R_T1, R_Cam, O_(Camera,pos.x)), // BD-Slot.
// D-pad Left → cam.pos.x -= 50. and_i fulfills BD-slot for load on R_Cam.
and_i(R_T3, R_T0, Pad_Left), branch_le_zero(R_T3, atom_offset(left_x, exit_left_x)), nop,
and_i(R_T3, R_T0, Pad_Left), branch_le_zero(R_T3, atom_offset(left_x, exit_left_x)), mac_yield_load(),
add_si(R_T1, R_T1, -50), store_word(R_T1, R_Cam, O_(Camera,pos.x)),
atom_label(exit_left_x)
/* D-pad Right → cam.pos.x += 50. Reuses R_T1 from Left. */
and_i(R_T3, R_T0, Pad_Right), branch_le_zero(R_T3, atom_offset(right_x, exit_right_x)), nop,
add_si(R_T1, R_T1, 50), store_word(R_T1, R_Cam, O_(Camera,pos.x)),
@@ -348,7 +327,6 @@ atom_label(exit_right_x)
and_i(R_T3, R_T0, Pad_Up), branch_le_zero(R_T3, atom_offset(up_y, exit_up_y)), nop,
add_si(R_T1, R_T1, -50), store_word(R_T1, R_Cam, O_(Camera,pos.y)),
atom_label(exit_up_y)
/* D-pad Down → cam.pos.y += 50. Reuses R_T1 from Up. */
and_i(R_T3, R_T0, Pad_Down), branch_le_zero(R_T3, atom_offset(down_y, exit_down_y)), nop,
add_si(R_T1, R_T1, 50), store_word(R_T1, R_Cam, O_(Camera,pos.y)),
@@ -359,23 +337,54 @@ atom_label(exit_down_y)
and_i(R_T3, R_T0, Pad_Cross), branch_le_zero(R_T3, atom_offset(cross_z, exit_cross_z)), nop,
add_si(R_T1, R_T1, -50), store_word(R_T1, R_Cam, O_(Camera,pos.z)),
atom_label(exit_cross_z)
/* D-pad Circle → cam.pos.z += 50. Reuses R_T1 from Cross. */
and_i(R_T3, R_T0, Pad_Circle), branch_le_zero(R_T3, atom_offset(circle_z, exit_circle_z)), nop,
add_si(R_T1, R_T1, 50), store_word(R_T1, R_Cam, O_(Camera,pos.z)),
atom_label(exit_circle_z)
mac_yield(),
mac_yield_tail(),
};
enum {
_LookAt_WIP,
R_LookAt = R_T0 atom_reg atom_type(MT3_S2S4*),
R_CamEye = R_T1 atom_reg atom_type(P3_S4*),
R_CamTarget = R_T2 atom_reg atom_type(P3_S4*),
R_WorldUp = R_T3 atom_reg atom_type(V3_S4*),
R_LkAt_Fwdx = R_T4 atom_reg atom_type(V3_S4*),
R_LkAt_Fwdy = R_T5 atom_reg atom_type(V3_S4*),
R_LkAt_Fwdz = R_T6 atom_reg atom_type(V3_S4*),
R_Eye_x = R_T7 atom_reg atom_type(V3_S4*),
R_Eye_y = R_T8 atom_reg atom_type(V3_S4*),
R_Eye_z = R_V0 atom_reg atom_type(V3_S4*),
R_LkAt_Up = R_T5 atom_reg atom_type(V3_S4*),
R_LkAt_Right = R_T6 atom_reg atom_type(V3_S4*),
R_AxisX = R_T7 atom_reg atom_type(V3_S4*),
R_AxisY = R_T8 atom_reg atom_type(V3_S4*),
R_AxisZ = R_T7 atom_reg atom_type(V3_S4*),
};
typedef Struct_(Binds_ResolveLookAt) {
U1 bla;
MT3_S2S4* look_at;
P3_S4* eye;
P3_S4* target;
V3_S4* up_in;
};
internal MipsAtom_(resolve_look_at) atom_info(atom_bind(Binds_ResolveLookAt)) {
add_ui_self(R_TapePtr, S_(Binds_ResolveLookAt)),
load_word(R_LookAt, R_TapePtr, O_(Binds_ResolveLookAt,look_at)),
load_word(R_CamEye, R_TapePtr, O_(Binds_ResolveLookAt,eye)),
load_word(R_CamTarget, R_TapePtr, O_(Binds_ResolveLookAt,target)),
load_word(R_WorldUp, R_TapePtr, O_(Binds_ResolveLookAt,up_in)),
add_ui_self( R_TapePtr, S_(Binds_ResolveLookAt)),
// load look_at and eye, then subtract (get direction), then normalize to unit vector.
mac_load_v3s4(R_LkAt_Fwdx, R_LkAt_Fwdy, R_LkAt_Fwdz, R_LookAt, 0),
mac_load_v3s4(R_Eye_x, R_Eye_y, R_Eye_z, R_CamEye, 0),
mac_sub_v3s4( R_LkAt_Fwdx, R_LkAt_Fwdy, R_LkAt_Fwdz,
R_Eye_x, R_Eye_y, R_Eye_z),
mac_yield(),
};
code/hello_camera/hello_camera.c
+41 -33
View File
@@ -93,36 +93,40 @@ I_ B1* prim__alloc(U4 type_width, Str8 type_name) {
#define prim_alloc(type) (type*)prim__alloc(S_(type), slit( stringify(type)))
void
resolve_look_at_c11(MT3_S2S4* look_at, V3_S4* eye, V3_S4* target, V3_S4* up_in) {
// TODO(Ed): Want to interpret this under the lens of Eric Lengyel's geometric algebra
resolve_look_at_c11(MT3_S2S4* look_at, P3_S4* eye, P3_S4* target, V3_S4* up_in) {
// RGA(Lengyel): Build matrix expansion of a rigid transformation. Corresponding motor is not constructed; we write the LA form for GTE.
// Preconditions: eye != target, up_in not collinear with (target - eye).
V3_S4 right, up, forward;
V3_S4 ux, uy, uz;
V3_S4 pos, off;
forward = target[0]; sub_v3s4(& forward, eye[0]);
normalize_v3s4(& forward, & uz);
forward = target[0]; sub_v3s4(& forward, eye[0]); // RGA(Lengyel): Affine point - point = zero-weight direction.
normalize_v3s4(& forward, & uz); // RGA(Lengyel): Normalize the direction bulk. Not finite-point unitization.
cross_v3s4(& uz, up_in, & right); normalize_v3s4(& right, & ux);
cross_v3s4(& uz, & ux, & up); normalize_v3s4(& up, & uy);
cross_v3s4(& uz, up_in, & right); normalize_v3s4(& right, & ux); // RGA(Lengyel): Complement(Wedge(forward, up_in)) -> right axis.
cross_v3s4(& uz, & ux, & up); normalize_v3s4(& up, & uy); // RGA(Lengyel): Complement(Wedge(forward, right)) -> up axis.
// RGA(Lengyel): matrix expansion of the world-to-camera rotation (basis rows).
look_at->m[0][0] = ux.x; look_at->m[0][1] = ux.y; look_at->m[0][2] = ux.z;
look_at->m[1][0] = uy.x; look_at->m[1][1] = uy.y; look_at->m[1][2] = uy.z;
look_at->m[2][0] = uz.x; look_at->m[2][1] = uz.y; look_at->m[2][2] = uz.z;
pos = eye[0]; mul_v3s4(& pos, v3s4(-1,-1,-1));
pos = eye[0]; mul_v3s4(& pos, v3s4(-1,-1,-1)); // RGA(Lengyel): -eye in world coordinates (spatial bulk only; implicit weight is dropped).
// RGA(Lengyel): R * (-eye) is the full matrix translation column.
// Motor translator would store half this displacement in m.xyz; GTE consumes full column.
mul_m3s2_v3s4(look_at, & pos, & off);
trans_m3s2(look_at, & off);
trans_m3s2( look_at, & off);
}
FI_ void camera_look_at_c11(Camera* c, V3_S4* target, V3_S4* up_in) { resolve_look_at_c11(& c->look_at, & c->pos, target, up_in); }
FI_ void camera_look_at_c11(Camera* c, P3_S4* target, V3_S4* up_in) { resolve_look_at_c11(& c->look_at, & c->pos, target, up_in); }
GCC_OPTIMIZATION_DISABLE
void update(PrimitiveArena* pa, U4* ordering_buf)
{
TapeBuilder tb = tb_make(slice_ut_arr(smem.MemTape));
if (1) // Pad Input
// Pad Input
{
tb.used = 0; tb_scope_run(& tb) {
// Grab latest state from bios.
@@ -133,32 +137,10 @@ void update(PrimitiveArena* pa, U4* ordering_buf)
tb_data_(raw, & smem.pad_raw[1]);
tb_data_(state, & smem.pad[1]);
// TODO(Ed): Implement based on below.
tb_emit_(pad_input_cam);
tb_data_(state, & smem.pad[0]);
tb_data_(cam, & smem.cam);
// if (pad0_btn_(Pad_Left)) {
// smem.cam.pos.x -= 50;
// }
// if (pad0_btn_(Pad_Right)) {
// smem.cam.pos.x += 50;
// }
// if (pad0_btn_(Pad_Up)) {
// smem.cam.pos.y -= 50;
// }
// if (pad0_btn_(Pad_Down)) {
// smem.cam.pos.y += 50;
// }
// if (pad0_btn_(Pad_Cross)) {
// smem.cam.pos.z -= 50;
// }
// if (pad0_btn_(Pad_Circle)) {
// smem.cam.pos.z += 50;
// }
// Demo input (not longer using)
// tb_emit_(pad_input_cube_rotation);
// tb_data_(state, & smem.pad[0]);
// tb_data_(cube_rot, & smem.cube.rot);
@@ -197,10 +179,36 @@ void update(PrimitiveArena* pa, U4* ordering_buf)
// Camera look at (Tape)
if (0)
{
MT3_S2S4* look_at = & smem.cam.look_at;
P3_S4* eye = & smem.cam.pos;
V3_S4* up_in = & v3s4(0, -fp_one, 0);
V3_S4 right, up, forward;
V3_S4 ux, uy, uz;
V3_S4 pos, off;
tb.used = 0; tb_scope_run(& tb) {
tb_emit_(resolve_look_at);
// tb_data_();
}
// forward = target[0]; sub_v3s4(& forward, eye[0]); // RGA(Lengyel): Affine point - point = zero-weight direction.
// normalize_v3s4(& forward, & uz); // RGA(Lengyel): Normalize the direction bulk. Not finite-point unitization.
cross_v3s4(& uz, up_in, & right); normalize_v3s4(& right, & ux); // RGA(Lengyel): Complement(Wedge(forward, up_in)) -> right axis.
cross_v3s4(& uz, & ux, & up); normalize_v3s4(& up, & uy); // RGA(Lengyel): Complement(Wedge(forward, right)) -> up axis.
// RGA(Lengyel): matrix expansion of the world-to-camera rotation (basis rows).
look_at->m[0][0] = ux.x; look_at->m[0][1] = ux.y; look_at->m[0][2] = ux.z;
look_at->m[1][0] = uy.x; look_at->m[1][1] = uy.y; look_at->m[1][2] = uy.z;
look_at->m[2][0] = uz.x; look_at->m[2][1] = uz.y; look_at->m[2][2] = uz.z;
pos = eye[0]; mul_v3s4(& pos, v3s4(-1,-1,-1)); // RGA(Lengyel): -eye in world coordinates (spatial bulk only; implicit weight is dropped).
// RGA(Lengyel): R * (-eye) is the full matrix translation column.
// Motor translator would store half this displacement in m.xyz; GTE consumes full column.
mul_m3s2_v3s4(look_at, & pos, & off);
trans_m3s2( look_at, & off);
}
// Draw cube
code/hello_camera/hello_camera.h
+3 -3
View File
@@ -61,7 +61,7 @@ I_ void ent_cube128_init(A8_V3_S2* verts, A6_V4_S2* faces) {
typedef Struct_(Ent_Cube) {
V3_S4 accel;
V3_S4 vel;
V3_S4 pos;
V3_S4 pos; // RGA(Lengyel): affine point with implicit weight one. Storage alias of V3_S4.
V3_S4 scale;
V3_S2 rot;
A8_V3_S2 verts;
@@ -88,7 +88,7 @@ I_ void ent_floor_init(A4_V3_S2* verts, A2_V3_S2* faces) {
};
typedef Struct_(Ent_Floor) {
V3_S4 accel;
V3_S4 pos;
V3_S4 pos; // RGA(Lengyel): affine point with implicit weight one. Storage alias of V3_S4.
V3_S4 scale;
V3_S2 rot;
A4_V3_S2 verts;
@@ -96,7 +96,7 @@ typedef Struct_(Ent_Floor) {
};
typedef Struct_(Camera) {
V3_S4 pos;
P3_S4 pos; // RGA(Lengyel): affine point with implicit weight one. Storage alias of V3_S4.
V3_S2 rot;
MT3_S2S4 look_at;
};