2 * Copyright (C) Mount0 Software, Harry Godden - All Rights Reserved
32 u32 lower
, upper
, target
, pole
;
41 struct mdl_keyframe
*anim_data
;
50 bindable_count
; /* TODO: try to place IK last in the rig from export
51 so that we dont always upload transforms for
52 useless cpu IK bones. */
55 static u32
skeleton_bone_id( struct skeleton
*skele
, const char *name
)
57 for( u32 i
=0; i
<skele
->bone_count
; i
++ )
59 if( !strcmp( skele
->bones
[i
].name
, name
))
65 static void keyframe_copy_pose( mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, int num
)
67 for( int i
=0; i
<num
; i
++ )
72 * Lerp between two sets of keyframes and store in dest. Rotations use Nlerp.
74 static void keyframe_lerp_pose( mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, float t
,
75 mdl_keyframe
*kfd
, int count
)
79 keyframe_copy_pose( kfa
, kfd
, count
);
84 keyframe_copy_pose( kfb
, kfd
, count
);
88 for( int i
=0; i
<count
; i
++ )
90 v3_lerp( kfa
[i
].co
, kfb
[i
].co
, t
, kfd
[i
].co
);
91 q_nlerp( kfa
[i
].q
, kfb
[i
].q
, t
, kfd
[i
].q
);
92 v3_lerp( kfa
[i
].s
, kfb
[i
].s
, t
, kfd
[i
].s
);
96 static void skeleton_lerp_pose( struct skeleton
*skele
,
97 mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, float t
,
100 keyframe_lerp_pose( kfa
, kfb
, t
, kfd
, skele
->bone_count
-1 );
104 * Sample animation between 2 closest frames using time value. Output is a
105 * keyframe buffer that is allocated with an appropriate size
107 static void skeleton_sample_anim( struct skeleton
*skele
,
108 struct skeleton_anim
*anim
,
110 mdl_keyframe
*output
)
112 float animtime
= time
*anim
->rate
;
114 u32 frame
= ((u32
)animtime
) % anim
->length
,
115 next
= (frame
+1) % anim
->length
;
117 float t
= vg_fractf( animtime
);
119 mdl_keyframe
*base
= anim
->anim_data
+ (skele
->bone_count
-1)*frame
,
120 *nbase
= anim
->anim_data
+ (skele
->bone_count
-1)*next
;
122 skeleton_lerp_pose( skele
, base
, nbase
, t
, output
);
125 static int skeleton_sample_anim_clamped( struct skeleton
*skele
,
126 struct skeleton_anim
*anim
,
128 mdl_keyframe
*output
)
130 float end
= (float)(anim
->length
-1) / anim
->rate
;
131 skeleton_sample_anim( skele
, anim
, vg_minf( end
, time
), output
);
139 typedef enum anim_apply
142 k_anim_apply_defer_ik
,
143 k_anim_apply_deffered_only
147 static int should_apply_bone( struct skeleton
*skele
, u32 id
, anim_apply type
)
149 struct skeleton_bone
*sb
= &skele
->bones
[ id
],
150 *sp
= &skele
->bones
[ sb
->parent
];
152 if( type
== k_anim_apply_defer_ik
)
154 if( (sp
->ik
&& !sb
->ik
) || sp
->defer
)
165 else if( type
== k_anim_apply_deffered_only
)
177 * Apply block of keyframes to skeletons final pose
179 static void skeleton_apply_pose( struct skeleton
*skele
, mdl_keyframe
*pose
,
180 anim_apply passtype
)
182 m4x3_identity( skele
->final_mtx
[0] );
183 skele
->bones
[0].defer
= 0;
184 skele
->bones
[0].ik
= 0;
186 for( int i
=1; i
<skele
->bone_count
; i
++ )
188 struct skeleton_bone
*sb
= &skele
->bones
[i
],
189 *sp
= &skele
->bones
[ sb
->parent
];
191 if( !should_apply_bone( skele
, i
, passtype
) )
200 v3_sub( skele
->bones
[i
].co
, skele
->bones
[sb
->parent
].co
, temp_delta
);
203 mdl_keyframe
*kf
= &pose
[i
-1];
204 q_m3x3( kf
->q
, posemtx
);
205 v3_copy( kf
->co
, posemtx
[3] );
206 v3_add( temp_delta
, posemtx
[3], posemtx
[3] );
209 m4x3_mul( skele
->final_mtx
[ sb
->parent
], posemtx
, skele
->final_mtx
[i
] );
214 * creates the reference inverse matrix for an IK bone, as it has an initial
215 * intrisic rotation based on the direction that the IK is setup..
217 static void skeleton_inverse_for_ik( struct skeleton
*skele
,
219 u32 id
, m3x3f inverse
)
221 v3_copy( ivaxis
, inverse
[0] );
222 v3_copy( skele
->bones
[id
].end
, inverse
[1] );
223 v3_normalize( inverse
[1] );
224 v3_cross( inverse
[0], inverse
[1], inverse
[2] );
225 m3x3_transpose( inverse
, inverse
);
229 * Creates inverse rotation matrices which the IK system uses.
231 static void skeleton_create_inverses( struct skeleton
*skele
)
233 /* IK: inverse 'plane-bone space' axis '(^axis,^bone,...)[base] */
234 for( int i
=0; i
<skele
->ik_count
; i
++ )
236 struct skeleton_ik
*ik
= &skele
->ik
[i
];
239 v3f iv0
, iv1
, ivaxis
;
240 v3_sub( skele
->bones
[ik
->target
].co
, skele
->bones
[ik
->lower
].co
, iv0
);
241 v3_sub( skele
->bones
[ik
->pole
].co
, skele
->bones
[ik
->lower
].co
, iv1
);
242 v3_cross( iv0
, iv1
, ivaxis
);
243 v3_normalize( ivaxis
);
245 skeleton_inverse_for_ik( skele
, ivaxis
, ik
->lower
, ik
->ia
);
246 skeleton_inverse_for_ik( skele
, ivaxis
, ik
->upper
, ik
->ib
);
251 * Apply a model matrix to all bones, should be done last
253 static void skeleton_apply_transform( struct skeleton
*skele
, m4x3f transform
)
255 for( int i
=0; i
<skele
->bone_count
; i
++ )
257 struct skeleton_bone
*sb
= &skele
->bones
[i
];
258 m4x3_mul( transform
, skele
->final_mtx
[i
], skele
->final_mtx
[i
] );
263 * Apply an inverse matrix to all bones which maps vertices from bind space into
264 * bone relative positions
266 static void skeleton_apply_inverses( struct skeleton
*skele
)
268 for( int i
=0; i
<skele
->bone_count
; i
++ )
270 struct skeleton_bone
*sb
= &skele
->bones
[i
];
272 m3x3_identity( inverse
);
273 v3_negate( sb
->co
, inverse
[3] );
275 m4x3_mul( skele
->final_mtx
[i
], inverse
, skele
->final_mtx
[i
] );
280 * Apply all IK modifiers (2 bone ik reference from blender is supported)
282 static void skeleton_apply_ik_pass( struct skeleton
*skele
)
284 for( int i
=0; i
<skele
->ik_count
; i
++ )
286 struct skeleton_ik
*ik
= &skele
->ik
[i
];
288 v3f v0
, /* base -> target */
289 v1
, /* base -> pole */
296 v3_copy( skele
->final_mtx
[ik
->lower
][3], co_base
);
297 v3_copy( skele
->final_mtx
[ik
->target
][3], co_target
);
298 v3_copy( skele
->final_mtx
[ik
->pole
][3], co_pole
);
300 v3_sub( co_target
, co_base
, v0
);
301 v3_sub( co_pole
, co_base
, v1
);
302 v3_cross( v0
, v1
, vaxis
);
303 v3_normalize( vaxis
);
305 v3_cross( vaxis
, v0
, v1
);
307 /* localize problem into [x:v0,y:v1] 2d plane */
308 v2f base
= { v3_dot( v0
, co_base
), v3_dot( v1
, co_base
) },
309 end
= { v3_dot( v0
, co_target
), v3_dot( v1
, co_target
) },
312 /* Compute angles (basic trig)*/
314 v2_sub( end
, base
, delta
);
317 l1
= v3_length( skele
->bones
[ik
->lower
].end
),
318 l2
= v3_length( skele
->bones
[ik
->upper
].end
),
319 d
= vg_clampf( v2_length(delta
), fabsf(l1
- l2
), l1
+l2
-0.00001f
),
320 c
= acosf( (l1
*l1
+ d
*d
- l2
*l2
) / (2.0f
*l1
*d
) ),
321 rot
= atan2f( delta
[1], delta
[0] ) + c
- VG_PIf
/2.0f
;
323 knee
[0] = sinf(-rot
) * l1
;
324 knee
[1] = cosf(-rot
) * l1
;
326 m4x3_identity( skele
->final_mtx
[ik
->lower
] );
327 m4x3_identity( skele
->final_mtx
[ik
->upper
] );
329 /* create rotation matrix */
331 v3_muladds( co_base
, v0
, knee
[0], co_knee
);
332 v3_muladds( co_knee
, v1
, knee
[1], co_knee
);
333 vg_line( co_base
, co_knee
, 0xff00ff00 );
336 v3_copy( vaxis
, transform
[0] );
337 v3_muls( v0
, knee
[0], transform
[1] );
338 v3_muladds( transform
[1], v1
, knee
[1], transform
[1] );
339 v3_normalize( transform
[1] );
340 v3_cross( transform
[0], transform
[1], transform
[2] );
341 v3_copy( co_base
, transform
[3] );
343 m3x3_mul( transform
, ik
->ia
, transform
);
344 m4x3_copy( transform
, skele
->final_mtx
[ik
->lower
] );
346 /* upper/knee bone */
347 v3_copy( vaxis
, transform
[0] );
348 v3_sub( co_target
, co_knee
, transform
[1] );
349 v3_normalize( transform
[1] );
350 v3_cross( transform
[0], transform
[1], transform
[2] );
351 v3_copy( co_knee
, transform
[3] );
353 m3x3_mul( transform
, ik
->ib
, transform
);
354 m4x3_copy( transform
, skele
->final_mtx
[ik
->upper
] );
359 * Applies the typical operations that you want for an IK rig:
360 * Pose, IK, Pose(deferred), Inverses, Transform
362 static void skeleton_apply_standard( struct skeleton
*skele
, mdl_keyframe
*pose
,
365 skeleton_apply_pose( skele
, pose
, k_anim_apply_defer_ik
);
366 skeleton_apply_ik_pass( skele
);
367 skeleton_apply_pose( skele
, pose
, k_anim_apply_deffered_only
);
368 skeleton_apply_inverses( skele
);
369 skeleton_apply_transform( skele
, transform
);
373 * Get an animation by name
375 static struct skeleton_anim
*skeleton_get_anim( struct skeleton
*skele
,
378 for( int i
=0; i
<skele
->anim_count
; i
++ )
380 struct skeleton_anim
*anim
= &skele
->anims
[i
];
382 if( !strcmp( anim
->name
, name
) )
389 /* Setup an animated skeleton from model */
390 static int skeleton_setup( struct skeleton
*skele
, mdl_header
*mdl
)
392 u32 bone_count
= 1, skeleton_root
= 0, ik_count
= 0, collider_count
= 0;
393 skele
->bone_count
= 0;
395 skele
->final_mtx
= NULL
;
398 struct classtype_skeleton
*inf
= NULL
;
400 for( u32 i
=0; i
<mdl
->node_count
; i
++ )
402 mdl_node
*pnode
= mdl_node_from_id( mdl
, i
);
404 if( pnode
->classtype
== k_classtype_skeleton
)
406 inf
= mdl_get_entdata( mdl
, pnode
);
407 if( skele
->bone_count
)
409 vg_error( "Multiple skeletons in model file\n" );
413 skele
->bone_count
= inf
->channels
;
414 skele
->ik_count
= inf
->ik_count
;
415 skele
->collider_count
= inf
->collider_count
;
416 skele
->bones
= malloc(sizeof(struct skeleton_bone
)*skele
->bone_count
);
417 skele
->ik
= malloc(sizeof(struct skeleton_ik
)*skele
->ik_count
);
420 else if( skele
->bone_count
)
422 int is_bone
= pnode
->classtype
== k_classtype_bone
;
426 if( bone_count
== skele
->bone_count
)
428 vg_error( "too many bones (%u/%u) @%s!\n",
429 bone_count
, skele
->bone_count
,
430 mdl_pstr( mdl
, pnode
->pstr_name
));
435 struct skeleton_bone
*sb
= &skele
->bones
[bone_count
];
436 struct classtype_bone
*bone_inf
= mdl_get_entdata( mdl
, pnode
);
437 int is_ik
= bone_inf
->ik_target
;
439 v3_copy( pnode
->co
, sb
->co
);
440 v3_copy( pnode
->s
, sb
->end
);
441 sb
->parent
= pnode
->parent
-skeleton_root
;
442 strncpy( sb
->name
, mdl_pstr(mdl
,pnode
->pstr_name
), 15 );
443 sb
->deform
= bone_inf
->deform
;
447 sb
->ik
= 1; /* TODO: place into new IK array */
448 skele
->bones
[ sb
->parent
].ik
= 1;
450 if( ik_count
== skele
->ik_count
)
452 vg_error( "Too many ik bones, corrupt model file\n" );
456 struct skeleton_ik
*ik
= &skele
->ik
[ ik_count
++ ];
457 ik
->upper
= bone_count
;
458 ik
->lower
= sb
->parent
;
459 ik
->target
= bone_inf
->ik_target
;
460 ik
->pole
= bone_inf
->ik_pole
;
467 sb
->collider
= bone_inf
->collider
;
468 box_copy( bone_inf
->hitbox
, sb
->hitbox
);
470 if( bone_inf
->collider
)
472 if( collider_count
== skele
->collider_count
)
474 vg_error( "Too many collider bones\n" );
492 vg_error( "No skeleton in model\n" );
496 if( collider_count
!= skele
->collider_count
)
498 vg_error( "Loaded %u colliders out of %u\n", collider_count
,
499 skele
->collider_count
);
503 if( bone_count
!= skele
->bone_count
)
505 vg_error( "Loaded %u bones out of %u\n", bone_count
, skele
->bone_count
);
509 if( ik_count
!= skele
->ik_count
)
511 vg_error( "Loaded %u ik bones out of %u\n", ik_count
, skele
->ik_count
);
515 /* fill in implicit root bone */
516 v3_zero( skele
->bones
[0].co
);
517 v3_copy( (v3f
){0.0f
,1.0f
,0.0f
}, skele
->bones
[0].end
);
518 skele
->bones
[0].parent
= 0xffffffff;
519 skele
->bones
[0].collider
= 0;
521 skele
->final_mtx
= malloc( sizeof(m4x3f
) * skele
->bone_count
);
522 skele
->anim_count
= inf
->anim_count
;
523 skele
->anims
= malloc( sizeof(struct skeleton_anim
) * inf
->anim_count
);
525 for( int i
=0; i
<inf
->anim_count
; i
++ )
527 mdl_animation
*anim
=
528 mdl_animation_from_id( mdl
, inf
->anim_start
+i
);
530 skele
->anims
[i
].rate
= anim
->rate
;
531 skele
->anims
[i
].length
= anim
->length
;
532 strncpy( skele
->anims
[i
].name
, mdl_pstr(mdl
, anim
->pstr_name
), 32 );
534 u32 total_keyframes
= (skele
->bone_count
-1)*anim
->length
;
535 size_t block_size
= sizeof(mdl_keyframe
) * total_keyframes
;
536 mdl_keyframe
*dst
= malloc( block_size
);
538 skele
->anims
[i
].anim_data
= dst
;
539 memcpy( dst
, mdl_get_animdata( mdl
, anim
), block_size
);
542 skeleton_create_inverses( skele
);
543 vg_success( "Loaded skeleton with %u bones\n", skele
->bone_count
);
544 vg_success( " %u colliders\n", skele
->collider_count
);
548 free( skele
->bones
);
553 static void skeleton_debug( struct skeleton
*skele
)
555 for( int i
=0; i
<skele
->bone_count
; i
++ )
557 struct skeleton_bone
*sb
= &skele
->bones
[i
];
560 v3_copy( sb
->co
, p0
);
561 v3_add( p0
, sb
->end
, p1
);
562 //vg_line( p0, p1, 0xffffffff );
564 m4x3_mulv( skele
->final_mtx
[i
], p0
, p0
);
565 m4x3_mulv( skele
->final_mtx
[i
], p1
, p1
);
571 vg_line( p0
, p1
, 0xff0000ff );
575 vg_line( p0
, p1
, 0xffcccccc );
579 vg_line( p0
, p1
, 0xff00ffff );
583 #endif /* SKELETON_H */