2 * Copyright (C) Mount0 Software, Harry Godden - All Rights Reserved
34 u32 lower
, upper
, target
, pole
;
43 struct mdl_keyframe
*anim_data
;
52 bindable_count
; /* TODO: try to place IK last in the rig from export
53 so that we dont always upload transforms for
54 useless cpu IK bones. */
57 static u32
skeleton_bone_id( struct skeleton
*skele
, const char *name
)
59 for( u32 i
=0; i
<skele
->bone_count
; i
++ )
61 if( !strcmp( skele
->bones
[i
].name
, name
))
67 static void keyframe_copy_pose( mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, int num
)
69 for( int i
=0; i
<num
; i
++ )
74 * Lerp between two sets of keyframes and store in dest. Rotations use Nlerp.
76 static void keyframe_lerp_pose( mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, float t
,
77 mdl_keyframe
*kfd
, int count
)
81 keyframe_copy_pose( kfa
, kfd
, count
);
86 keyframe_copy_pose( kfb
, kfd
, count
);
90 for( int i
=0; i
<count
; i
++ )
92 v3_lerp( kfa
[i
].co
, kfb
[i
].co
, t
, kfd
[i
].co
);
93 q_nlerp( kfa
[i
].q
, kfb
[i
].q
, t
, kfd
[i
].q
);
94 v3_lerp( kfa
[i
].s
, kfb
[i
].s
, t
, kfd
[i
].s
);
98 static void skeleton_lerp_pose( struct skeleton
*skele
,
99 mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, float t
,
102 keyframe_lerp_pose( kfa
, kfb
, t
, kfd
, skele
->bone_count
-1 );
106 * Sample animation between 2 closest frames using time value. Output is a
107 * keyframe buffer that is allocated with an appropriate size
109 static void skeleton_sample_anim( struct skeleton
*skele
,
110 struct skeleton_anim
*anim
,
112 mdl_keyframe
*output
)
114 float animtime
= time
*anim
->rate
;
116 u32 frame
= ((u32
)animtime
) % anim
->length
,
117 next
= (frame
+1) % anim
->length
;
119 float t
= vg_fractf( animtime
);
121 mdl_keyframe
*base
= anim
->anim_data
+ (skele
->bone_count
-1)*frame
,
122 *nbase
= anim
->anim_data
+ (skele
->bone_count
-1)*next
;
124 skeleton_lerp_pose( skele
, base
, nbase
, t
, output
);
127 static int skeleton_sample_anim_clamped( struct skeleton
*skele
,
128 struct skeleton_anim
*anim
,
130 mdl_keyframe
*output
)
132 float end
= (float)(anim
->length
-1) / anim
->rate
;
133 skeleton_sample_anim( skele
, anim
, vg_minf( end
, time
), output
);
141 typedef enum anim_apply
144 k_anim_apply_defer_ik
,
145 k_anim_apply_deffered_only
149 static int should_apply_bone( struct skeleton
*skele
, u32 id
, anim_apply type
)
151 struct skeleton_bone
*sb
= &skele
->bones
[ id
],
152 *sp
= &skele
->bones
[ sb
->parent
];
154 if( type
== k_anim_apply_defer_ik
)
156 if( (sp
->ik
&& !sb
->ik
) || sp
->defer
)
167 else if( type
== k_anim_apply_deffered_only
)
179 * Apply block of keyframes to skeletons final pose
181 static void skeleton_apply_pose( struct skeleton
*skele
, mdl_keyframe
*pose
,
182 anim_apply passtype
)
184 m4x3_identity( skele
->final_mtx
[0] );
185 skele
->bones
[0].defer
= 0;
186 skele
->bones
[0].ik
= 0;
188 for( int i
=1; i
<skele
->bone_count
; i
++ )
190 struct skeleton_bone
*sb
= &skele
->bones
[i
],
191 *sp
= &skele
->bones
[ sb
->parent
];
193 if( !should_apply_bone( skele
, i
, passtype
) )
202 v3_sub( skele
->bones
[i
].co
, skele
->bones
[sb
->parent
].co
, temp_delta
);
205 mdl_keyframe
*kf
= &pose
[i
-1];
206 q_m3x3( kf
->q
, posemtx
);
207 v3_copy( kf
->co
, posemtx
[3] );
208 v3_add( temp_delta
, posemtx
[3], posemtx
[3] );
211 m4x3_mul( skele
->final_mtx
[ sb
->parent
], posemtx
, skele
->final_mtx
[i
] );
216 * creates the reference inverse matrix for an IK bone, as it has an initial
217 * intrisic rotation based on the direction that the IK is setup..
219 static void skeleton_inverse_for_ik( struct skeleton
*skele
,
221 u32 id
, m3x3f inverse
)
223 v3_copy( ivaxis
, inverse
[0] );
224 v3_copy( skele
->bones
[id
].end
, inverse
[1] );
225 v3_normalize( inverse
[1] );
226 v3_cross( inverse
[0], inverse
[1], inverse
[2] );
227 m3x3_transpose( inverse
, inverse
);
231 * Creates inverse rotation matrices which the IK system uses.
233 static void skeleton_create_inverses( struct skeleton
*skele
)
235 /* IK: inverse 'plane-bone space' axis '(^axis,^bone,...)[base] */
236 for( int i
=0; i
<skele
->ik_count
; i
++ )
238 struct skeleton_ik
*ik
= &skele
->ik
[i
];
241 v3f iv0
, iv1
, ivaxis
;
242 v3_sub( skele
->bones
[ik
->target
].co
, skele
->bones
[ik
->lower
].co
, iv0
);
243 v3_sub( skele
->bones
[ik
->pole
].co
, skele
->bones
[ik
->lower
].co
, iv1
);
244 v3_cross( iv0
, iv1
, ivaxis
);
245 v3_normalize( ivaxis
);
247 skeleton_inverse_for_ik( skele
, ivaxis
, ik
->lower
, ik
->ia
);
248 skeleton_inverse_for_ik( skele
, ivaxis
, ik
->upper
, ik
->ib
);
253 * Apply a model matrix to all bones, should be done last
255 static void skeleton_apply_transform( struct skeleton
*skele
, m4x3f transform
)
257 for( int i
=0; i
<skele
->bone_count
; i
++ )
259 struct skeleton_bone
*sb
= &skele
->bones
[i
];
260 m4x3_mul( transform
, skele
->final_mtx
[i
], skele
->final_mtx
[i
] );
265 * Apply an inverse matrix to all bones which maps vertices from bind space into
266 * bone relative positions
268 static void skeleton_apply_inverses( struct skeleton
*skele
)
270 for( int i
=0; i
<skele
->bone_count
; i
++ )
272 struct skeleton_bone
*sb
= &skele
->bones
[i
];
274 m3x3_identity( inverse
);
275 v3_negate( sb
->co
, inverse
[3] );
277 m4x3_mul( skele
->final_mtx
[i
], inverse
, skele
->final_mtx
[i
] );
282 * Apply all IK modifiers (2 bone ik reference from blender is supported)
284 static void skeleton_apply_ik_pass( struct skeleton
*skele
)
286 for( int i
=0; i
<skele
->ik_count
; i
++ )
288 struct skeleton_ik
*ik
= &skele
->ik
[i
];
290 v3f v0
, /* base -> target */
291 v1
, /* base -> pole */
298 v3_copy( skele
->final_mtx
[ik
->lower
][3], co_base
);
299 v3_copy( skele
->final_mtx
[ik
->target
][3], co_target
);
300 v3_copy( skele
->final_mtx
[ik
->pole
][3], co_pole
);
302 v3_sub( co_target
, co_base
, v0
);
303 v3_sub( co_pole
, co_base
, v1
);
304 v3_cross( v0
, v1
, vaxis
);
305 v3_normalize( vaxis
);
307 v3_cross( vaxis
, v0
, v1
);
309 /* localize problem into [x:v0,y:v1] 2d plane */
310 v2f base
= { v3_dot( v0
, co_base
), v3_dot( v1
, co_base
) },
311 end
= { v3_dot( v0
, co_target
), v3_dot( v1
, co_target
) },
314 /* Compute angles (basic trig)*/
316 v2_sub( end
, base
, delta
);
319 l1
= v3_length( skele
->bones
[ik
->lower
].end
),
320 l2
= v3_length( skele
->bones
[ik
->upper
].end
),
321 d
= vg_clampf( v2_length(delta
), fabsf(l1
- l2
), l1
+l2
-0.00001f
),
322 c
= acosf( (l1
*l1
+ d
*d
- l2
*l2
) / (2.0f
*l1
*d
) ),
323 rot
= atan2f( delta
[1], delta
[0] ) + c
- VG_PIf
/2.0f
;
325 knee
[0] = sinf(-rot
) * l1
;
326 knee
[1] = cosf(-rot
) * l1
;
328 m4x3_identity( skele
->final_mtx
[ik
->lower
] );
329 m4x3_identity( skele
->final_mtx
[ik
->upper
] );
331 /* create rotation matrix */
333 v3_muladds( co_base
, v0
, knee
[0], co_knee
);
334 v3_muladds( co_knee
, v1
, knee
[1], co_knee
);
335 vg_line( co_base
, co_knee
, 0xff00ff00 );
338 v3_copy( vaxis
, transform
[0] );
339 v3_muls( v0
, knee
[0], transform
[1] );
340 v3_muladds( transform
[1], v1
, knee
[1], transform
[1] );
341 v3_normalize( transform
[1] );
342 v3_cross( transform
[0], transform
[1], transform
[2] );
343 v3_copy( co_base
, transform
[3] );
345 m3x3_mul( transform
, ik
->ia
, transform
);
346 m4x3_copy( transform
, skele
->final_mtx
[ik
->lower
] );
348 /* upper/knee bone */
349 v3_copy( vaxis
, transform
[0] );
350 v3_sub( co_target
, co_knee
, transform
[1] );
351 v3_normalize( transform
[1] );
352 v3_cross( transform
[0], transform
[1], transform
[2] );
353 v3_copy( co_knee
, transform
[3] );
355 m3x3_mul( transform
, ik
->ib
, transform
);
356 m4x3_copy( transform
, skele
->final_mtx
[ik
->upper
] );
361 * Applies the typical operations that you want for an IK rig:
362 * Pose, IK, Pose(deferred), Inverses, Transform
364 static void skeleton_apply_standard( struct skeleton
*skele
, mdl_keyframe
*pose
,
367 skeleton_apply_pose( skele
, pose
, k_anim_apply_defer_ik
);
368 skeleton_apply_ik_pass( skele
);
369 skeleton_apply_pose( skele
, pose
, k_anim_apply_deffered_only
);
370 skeleton_apply_inverses( skele
);
371 skeleton_apply_transform( skele
, transform
);
375 * Get an animation by name
377 static struct skeleton_anim
*skeleton_get_anim( struct skeleton
*skele
,
380 for( int i
=0; i
<skele
->anim_count
; i
++ )
382 struct skeleton_anim
*anim
= &skele
->anims
[i
];
384 if( !strcmp( anim
->name
, name
) )
391 /* Setup an animated skeleton from model */
392 static int skeleton_setup( struct skeleton
*skele
, mdl_header
*mdl
)
394 u32 bone_count
= 1, skeleton_root
= 0, ik_count
= 0, collider_count
= 0;
395 skele
->bone_count
= 0;
397 skele
->final_mtx
= NULL
;
400 struct classtype_skeleton
*inf
= NULL
;
402 for( u32 i
=0; i
<mdl
->node_count
; i
++ )
404 mdl_node
*pnode
= mdl_node_from_id( mdl
, i
);
406 if( pnode
->classtype
== k_classtype_skeleton
)
408 inf
= mdl_get_entdata( mdl
, pnode
);
409 if( skele
->bone_count
)
411 vg_error( "Multiple skeletons in model file\n" );
415 skele
->bone_count
= inf
->channels
;
416 skele
->ik_count
= inf
->ik_count
;
417 skele
->collider_count
= inf
->collider_count
;
418 skele
->bones
= malloc(sizeof(struct skeleton_bone
)*skele
->bone_count
);
419 skele
->ik
= malloc(sizeof(struct skeleton_ik
)*skele
->ik_count
);
422 else if( skele
->bone_count
)
424 int is_bone
= pnode
->classtype
== k_classtype_bone
;
428 if( bone_count
== skele
->bone_count
)
430 vg_error( "too many bones (%u/%u) @%s!\n",
431 bone_count
, skele
->bone_count
,
432 mdl_pstr( mdl
, pnode
->pstr_name
));
437 struct skeleton_bone
*sb
= &skele
->bones
[bone_count
];
438 struct classtype_bone
*bone_inf
= mdl_get_entdata( mdl
, pnode
);
439 int is_ik
= bone_inf
->ik_target
;
441 v3_copy( pnode
->co
, sb
->co
);
442 v3_copy( pnode
->s
, sb
->end
);
443 sb
->parent
= pnode
->parent
-skeleton_root
;
444 strncpy( sb
->name
, mdl_pstr(mdl
,pnode
->pstr_name
), 15 );
445 sb
->deform
= bone_inf
->deform
;
449 sb
->ik
= 1; /* TODO: place into new IK array */
450 skele
->bones
[ sb
->parent
].ik
= 1;
452 if( ik_count
== skele
->ik_count
)
454 vg_error( "Too many ik bones, corrupt model file\n" );
458 struct skeleton_ik
*ik
= &skele
->ik
[ ik_count
++ ];
459 ik
->upper
= bone_count
;
460 ik
->lower
= sb
->parent
;
461 ik
->target
= bone_inf
->ik_target
;
462 ik
->pole
= bone_inf
->ik_pole
;
469 sb
->collider
= bone_inf
->collider
;
471 box_copy( bone_inf
->hitbox
, sb
->hitbox
);
473 if( bone_inf
->collider
)
475 if( collider_count
== skele
->collider_count
)
477 vg_error( "Too many collider bones\n" );
495 vg_error( "No skeleton in model\n" );
499 if( collider_count
!= skele
->collider_count
)
501 vg_error( "Loaded %u colliders out of %u\n", collider_count
,
502 skele
->collider_count
);
506 if( bone_count
!= skele
->bone_count
)
508 vg_error( "Loaded %u bones out of %u\n", bone_count
, skele
->bone_count
);
512 if( ik_count
!= skele
->ik_count
)
514 vg_error( "Loaded %u ik bones out of %u\n", ik_count
, skele
->ik_count
);
518 /* fill in implicit root bone */
519 v3_zero( skele
->bones
[0].co
);
520 v3_copy( (v3f
){0.0f
,1.0f
,0.0f
}, skele
->bones
[0].end
);
521 skele
->bones
[0].parent
= 0xffffffff;
522 skele
->bones
[0].collider
= 0;
524 skele
->final_mtx
= malloc( sizeof(m4x3f
) * skele
->bone_count
);
525 skele
->anim_count
= inf
->anim_count
;
526 skele
->anims
= malloc( sizeof(struct skeleton_anim
) * inf
->anim_count
);
528 for( int i
=0; i
<inf
->anim_count
; i
++ )
530 mdl_animation
*anim
=
531 mdl_animation_from_id( mdl
, inf
->anim_start
+i
);
533 skele
->anims
[i
].rate
= anim
->rate
;
534 skele
->anims
[i
].length
= anim
->length
;
535 strncpy( skele
->anims
[i
].name
, mdl_pstr(mdl
, anim
->pstr_name
), 32 );
537 u32 total_keyframes
= (skele
->bone_count
-1)*anim
->length
;
538 size_t block_size
= sizeof(mdl_keyframe
) * total_keyframes
;
539 mdl_keyframe
*dst
= malloc( block_size
);
541 skele
->anims
[i
].anim_data
= dst
;
542 memcpy( dst
, mdl_get_animdata( mdl
, anim
), block_size
);
545 skeleton_create_inverses( skele
);
546 vg_success( "Loaded skeleton with %u bones\n", skele
->bone_count
);
547 vg_success( " %u colliders\n", skele
->collider_count
);
551 free( skele
->bones
);
556 static void skeleton_debug( struct skeleton
*skele
)
558 for( int i
=0; i
<skele
->bone_count
; i
++ )
560 struct skeleton_bone
*sb
= &skele
->bones
[i
];
563 v3_copy( sb
->co
, p0
);
564 v3_add( p0
, sb
->end
, p1
);
565 //vg_line( p0, p1, 0xffffffff );
567 m4x3_mulv( skele
->final_mtx
[i
], p0
, p0
);
568 m4x3_mulv( skele
->final_mtx
[i
], p1
, p1
);
574 vg_line( p0
, p1
, 0xff0000ff );
578 vg_line( p0
, p1
, 0xffcccccc );
582 vg_line( p0
, p1
, 0xff00ffff );
586 #endif /* SKELETON_H */