23 u32 lower
, upper
, target
, pole
;
32 struct mdl_keyframe
*anim_data
;
40 bindable_count
; /* TODO: try to place IK last in the rig from export
41 so that we dont always upload transforms for
42 useless cpu IK bones. */
46 * Lerp between two sets of keyframes and store in dest. Rotations use Nlerp.
48 static void keyframe_lerp_pose( mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, float t
,
49 mdl_keyframe
*kfd
, int count
)
51 for( int i
=0; i
<count
; i
++ )
53 v3_lerp( kfa
[i
].co
, kfb
[i
].co
, t
, kfd
[i
].co
);
54 q_nlerp( kfa
[i
].q
, kfb
[i
].q
, t
, kfd
[i
].q
);
55 v3_lerp( kfa
[i
].s
, kfb
[i
].s
, t
, kfd
[i
].s
);
59 static void skeleton_lerp_pose( struct skeleton
*skele
,
60 mdl_keyframe
*kfa
, mdl_keyframe
*kfb
, float t
,
63 keyframe_lerp_pose( kfa
, kfb
, t
, kfd
, skele
->bone_count
-1 );
67 * Sample animation between 2 closest frames using time value. Output is a
68 * keyframe buffer that is allocated with an appropriate size
70 static void skeleton_sample_anim( struct skeleton
*skele
,
71 struct skeleton_anim
*anim
,
73 mdl_keyframe
*output
)
75 float animtime
= time
*anim
->rate
;
77 u32 frame
= ((u32
)animtime
) % anim
->length
,
78 next
= (frame
+1) % anim
->length
;
80 float t
= vg_fractf( animtime
);
82 mdl_keyframe
*base
= anim
->anim_data
+ (skele
->bone_count
-1)*frame
,
83 *nbase
= anim
->anim_data
+ (skele
->bone_count
-1)*next
;
85 skeleton_lerp_pose( skele
, base
, nbase
, t
, output
);
88 typedef enum anim_apply
91 k_anim_apply_defer_ik
,
92 k_anim_apply_deffered_only
96 static int should_apply_bone( struct skeleton
*skele
, u32 id
, anim_apply type
)
98 struct skeleton_bone
*sb
= &skele
->bones
[ id
],
99 *sp
= &skele
->bones
[ sb
->parent
];
101 if( type
== k_anim_apply_defer_ik
)
103 if( (sp
->ik
&& !sb
->ik
) || sp
->defer
)
114 else if( type
== k_anim_apply_deffered_only
)
126 * Apply block of keyframes to skeletons final pose
128 static void skeleton_apply_pose( struct skeleton
*skele
, mdl_keyframe
*pose
,
129 anim_apply passtype
)
131 m4x3_identity( skele
->final_mtx
[0] );
132 skele
->bones
[0].defer
= 0;
133 skele
->bones
[0].ik
= 0;
135 for( int i
=1; i
<skele
->bone_count
; i
++ )
137 struct skeleton_bone
*sb
= &skele
->bones
[i
],
138 *sp
= &skele
->bones
[ sb
->parent
];
140 if( !should_apply_bone( skele
, i
, passtype
) )
149 v3_sub( skele
->bones
[i
].co
, skele
->bones
[sb
->parent
].co
, temp_delta
);
152 mdl_keyframe
*kf
= &pose
[i
-1];
153 q_m3x3( kf
->q
, posemtx
);
154 v3_copy( kf
->co
, posemtx
[3] );
155 v3_add( temp_delta
, posemtx
[3], posemtx
[3] );
158 m4x3_mul( skele
->final_mtx
[ sb
->parent
], posemtx
, skele
->final_mtx
[i
] );
163 * creates the reference inverse matrix for an IK bone, as it has an initial
164 * intrisic rotation based on the direction that the IK is setup..
166 static void skeleton_inverse_for_ik( struct skeleton
*skele
,
168 u32 id
, m3x3f inverse
)
170 v3_copy( ivaxis
, inverse
[0] );
171 v3_copy( skele
->bones
[id
].end
, inverse
[1] );
172 v3_normalize( inverse
[1] );
173 v3_cross( inverse
[0], inverse
[1], inverse
[2] );
174 m3x3_transpose( inverse
, inverse
);
177 static void skeleton_create_inverses( struct skeleton
*skele
)
179 /* IK: inverse 'plane-bone space' axis '(^axis,^bone,...)[base] */
180 for( int i
=0; i
<skele
->ik_count
; i
++ )
182 struct skeleton_ik
*ik
= &skele
->ik
[i
];
185 v3f iv0
, iv1
, ivaxis
;
186 v3_sub( skele
->bones
[ik
->target
].co
, skele
->bones
[ik
->lower
].co
, iv0
);
187 v3_sub( skele
->bones
[ik
->pole
].co
, skele
->bones
[ik
->lower
].co
, iv1
);
188 v3_cross( iv0
, iv1
, ivaxis
);
189 v3_normalize( ivaxis
);
191 skeleton_inverse_for_ik( skele
, ivaxis
, ik
->lower
, ik
->ia
);
192 skeleton_inverse_for_ik( skele
, ivaxis
, ik
->upper
, ik
->ib
);
196 static void skeleton_apply_transform( struct skeleton
*skele
, m4x3f transform
)
198 /* bone space inverse matrix */
199 for( int i
=0; i
<skele
->bone_count
; i
++ )
201 struct skeleton_bone
*sb
= &skele
->bones
[i
];
202 m4x3_mul( transform
, skele
->final_mtx
[i
], skele
->final_mtx
[i
] );
206 static void skeleton_apply_inverses( struct skeleton
*skele
)
208 for( int i
=0; i
<skele
->bone_count
; i
++ )
210 struct skeleton_bone
*sb
= &skele
->bones
[i
];
212 m3x3_identity( inverse
);
213 v3_negate( sb
->co
, inverse
[3] );
215 m4x3_mul( skele
->final_mtx
[i
], inverse
, skele
->final_mtx
[i
] );
220 * Apply all IK modifiers (2 bone ik reference from blender is supported)
222 static void skeleton_apply_ik_pass( struct skeleton
*skele
)
224 for( int i
=0; i
<skele
->ik_count
; i
++ )
226 struct skeleton_ik
*ik
= &skele
->ik
[i
];
228 v3f v0
, /* base -> target */
229 v1
, /* base -> pole */
236 v3_copy( skele
->final_mtx
[ik
->lower
][3], co_base
);
237 v3_copy( skele
->final_mtx
[ik
->target
][3], co_target
);
238 v3_copy( skele
->final_mtx
[ik
->pole
][3], co_pole
);
240 v3_sub( co_target
, co_base
, v0
);
241 v3_sub( co_pole
, co_base
, v1
);
242 v3_cross( v0
, v1
, vaxis
);
243 v3_normalize( vaxis
);
245 v3_cross( vaxis
, v0
, v1
);
247 /* localize problem into [x:v0,y:v1] 2d plane */
248 v2f base
= { v3_dot( v0
, co_base
), v3_dot( v1
, co_base
) },
249 end
= { v3_dot( v0
, co_target
), v3_dot( v1
, co_target
) },
252 /* Compute angles (basic trig)*/
254 v2_sub( end
, base
, delta
);
257 l1
= v3_length( skele
->bones
[ik
->lower
].end
),
258 l2
= v3_length( skele
->bones
[ik
->upper
].end
),
259 d
= vg_clampf( v2_length(delta
), fabsf(l1
- l2
), l1
+l2
-0.00001f
),
260 c
= acosf( (l1
*l1
+ d
*d
- l2
*l2
) / (2.0f
*l1
*d
) ),
261 rot
= atan2f( delta
[1], delta
[0] ) + c
- VG_PIf
/2.0f
;
263 knee
[0] = sinf(-rot
) * l1
;
264 knee
[1] = cosf(-rot
) * l1
;
266 m4x3_identity( skele
->final_mtx
[ik
->lower
] );
267 m4x3_identity( skele
->final_mtx
[ik
->upper
] );
269 /* create rotation matrix */
271 v3_muladds( co_base
, v0
, knee
[0], co_knee
);
272 v3_muladds( co_knee
, v1
, knee
[1], co_knee
);
273 vg_line( co_base
, co_knee
, 0xff00ff00 );
276 v3_copy( vaxis
, transform
[0] );
277 v3_muls( v0
, knee
[0], transform
[1] );
278 v3_muladds( transform
[1], v1
, knee
[1], transform
[1] );
279 v3_normalize( transform
[1] );
280 v3_cross( transform
[0], transform
[1], transform
[2] );
281 v3_copy( co_base
, transform
[3] );
283 m3x3_mul( transform
, ik
->ia
, transform
);
284 m4x3_copy( transform
, skele
->final_mtx
[ik
->lower
] );
286 /* upper/knee bone */
287 v3_copy( vaxis
, transform
[0] );
288 v3_sub( co_target
, co_knee
, transform
[1] );
289 v3_normalize( transform
[1] );
290 v3_cross( transform
[0], transform
[1], transform
[2] );
291 v3_copy( co_knee
, transform
[3] );
293 m3x3_mul( transform
, ik
->ib
, transform
);
294 m4x3_copy( transform
, skele
->final_mtx
[ik
->upper
] );
298 static struct skeleton_anim
*skeleton_get_anim( struct skeleton
*skele
,
301 for( int i
=0; i
<skele
->anim_count
; i
++ )
303 struct skeleton_anim
*anim
= &skele
->anims
[i
];
305 if( !strcmp( anim
->name
, name
) )
312 /* Setup an animated skeleton from model */
313 static int skeleton_setup( struct skeleton
*skele
, mdl_header
*mdl
)
315 u32 bone_count
= 1, skeleton_root
= 0, ik_count
= 0;
316 skele
->bone_count
= 0;
318 skele
->final_mtx
= NULL
;
321 struct classtype_skeleton
*inf
= NULL
;
323 for( u32 i
=0; i
<mdl
->node_count
; i
++ )
325 mdl_node
*pnode
= mdl_node_from_id( mdl
, i
);
327 if( pnode
->classtype
== k_classtype_skeleton
)
329 inf
= mdl_get_entdata( mdl
, pnode
);
330 if( skele
->bone_count
)
332 vg_error( "Multiple skeletons in model file\n" );
336 skele
->bone_count
= inf
->channels
;
337 skele
->ik_count
= inf
->ik_count
;
338 skele
->bones
= malloc(sizeof(struct skeleton_bone
)*skele
->bone_count
);
339 skele
->ik
= malloc(sizeof(struct skeleton_ik
)*skele
->ik_count
);
342 else if( skele
->bone_count
)
344 int is_ik
= pnode
->classtype
== k_classtype_ik_bone
,
345 is_bone
= (pnode
->classtype
== k_classtype_bone
) || is_ik
;
349 if( bone_count
== skele
->bone_count
)
351 vg_error( "too many bones (%u/%u) @%s!\n",
352 bone_count
, skele
->bone_count
,
353 mdl_pstr( mdl
, pnode
->pstr_name
));
358 struct skeleton_bone
*sb
= &skele
->bones
[bone_count
];
360 v3_copy( pnode
->co
, sb
->co
);
361 v3_copy( pnode
->s
, sb
->end
);
362 sb
->parent
= pnode
->parent
-skeleton_root
;
366 struct classtype_ik_bone
*ik_inf
= mdl_get_entdata( mdl
, pnode
);
367 sb
->deform
= ik_inf
->deform
;
368 sb
->ik
= 1; /* TODO: place into new IK array */
369 skele
->bones
[ sb
->parent
].ik
= 1;
371 if( ik_count
== skele
->ik_count
)
373 vg_error( "Too many ik bones, corrupt model file\n" );
377 struct skeleton_ik
*ik
= &skele
->ik
[ ik_count
++ ];
378 ik
->upper
= bone_count
;
379 ik
->lower
= sb
->parent
;
380 ik
->target
= ik_inf
->target
;
381 ik
->pole
= ik_inf
->pole
;
385 struct classtype_bone
*bone_inf
= mdl_get_entdata( mdl
, pnode
);
386 sb
->deform
= bone_inf
->deform
;
401 vg_error( "No skeleton in model\n" );
405 if( bone_count
!= skele
->bone_count
)
407 vg_error( "Loaded %u bones out of %u\n", bone_count
, skele
->bone_count
);
411 if( ik_count
!= skele
->ik_count
)
413 vg_error( "Loaded %u ik bones out of %u\n", ik_count
, skele
->ik_count
);
417 /* fill in implicit root bone */
418 v3_zero( skele
->bones
[0].co
);
419 v3_copy( (v3f
){0.0f
,1.0f
,0.0f
}, skele
->bones
[0].end
);
420 skele
->bones
[0].parent
= 0xffffffff;
422 skele
->final_mtx
= malloc( sizeof(m4x3f
) * skele
->bone_count
);
423 skele
->anim_count
= inf
->anim_count
;
424 skele
->anims
= malloc( sizeof(struct skeleton_anim
) * inf
->anim_count
);
426 for( int i
=0; i
<inf
->anim_count
; i
++ )
428 mdl_animation
*anim
=
429 mdl_animation_from_id( mdl
, inf
->anim_start
+i
);
431 skele
->anims
[i
].rate
= anim
->rate
;
432 skele
->anims
[i
].length
= anim
->length
;
433 strncpy( skele
->anims
[i
].name
, mdl_pstr(mdl
, anim
->pstr_name
), 32 );
435 u32 total_keyframes
= (skele
->bone_count
-1)*anim
->length
;
436 size_t block_size
= sizeof(mdl_keyframe
) * total_keyframes
;
437 mdl_keyframe
*dst
= malloc( block_size
);
439 skele
->anims
[i
].anim_data
= dst
;
440 memcpy( dst
, mdl_get_animdata( mdl
, anim
), block_size
);
443 skeleton_create_inverses( skele
);
444 vg_success( "Loaded skeleton with %u bones\n", skele
->bone_count
);
448 free( skele
->bones
);
453 static void skeleton_debug( struct skeleton
*skele
)
455 for( int i
=0; i
<skele
->bone_count
; i
++ )
457 struct skeleton_bone
*sb
= &skele
->bones
[i
];
460 v3_copy( sb
->co
, p0
);
461 v3_add( p0
, sb
->end
, p1
);
462 //vg_line( p0, p1, 0xffffffff );
464 m4x3_mulv( skele
->final_mtx
[i
], p0
, p0
);
465 m4x3_mulv( skele
->final_mtx
[i
], p1
, p1
);
471 vg_line( p0
, p1
, 0xff0000ff );
475 vg_line( p0
, p1
, 0xffcccccc );
479 vg_line( p0
, p1
, 0xff00ffff );
483 #endif /* SKELETON_H */