2 * Copyright (C) 2021-2022 Mt.ZERO Software, Harry Godden - All Rights Reserved
6 * Resources: Box2D - Erin Catto
16 VG_STATIC
void rb_tangent_basis( v3f n
, v3f tx
, v3f ty
);
17 VG_STATIC bh_system bh_system_rigidbodies
;
23 * -----------------------------------------------------------------------------
25 * -----------------------------------------------------------------------------
29 k_rb_rate
= (1.0/VG_TIMESTEP_FIXED
),
30 k_rb_delta
= (1.0/k_rb_rate
),
32 k_damp_linear
= 0.1f
, /* scale velocity 1/(1+x) */
33 k_damp_angular
= 0.1f
, /* scale angular 1/(1+x) */
34 k_penetration_slop
= 0.01f
,
35 k_inertia_scale
= 8.0f
,
36 k_phys_baumgarte
= 0.2f
,
41 k_joint_correction
= 0.01f
,
42 k_joint_impulse
= 1.0f
,
43 k_joint_bias
= 0.08f
; /* positional joints */
45 VG_STATIC
void rb_register_cvar(void)
47 vg_var_push( (struct vg_var
){
48 .name
= "k_limit_bias", .data
= &k_limit_bias
,
49 .data_type
= k_var_dtype_f32
, .opt_f32
= {.clamp
= 0}, .persistent
= 1
52 vg_var_push( (struct vg_var
){
53 .name
= "k_joint_bias", .data
= &k_joint_bias
,
54 .data_type
= k_var_dtype_f32
, .opt_f32
= {.clamp
= 0}, .persistent
= 1
57 vg_var_push( (struct vg_var
){
58 .name
= "k_joint_correction", .data
= &k_joint_correction
,
59 .data_type
= k_var_dtype_f32
, .opt_f32
= {.clamp
= 0}, .persistent
= 1
62 vg_var_push( (struct vg_var
){
63 .name
= "k_joint_impulse", .data
= &k_joint_impulse
,
64 .data_type
= k_var_dtype_f32
, .opt_f32
= {.clamp
= 0}, .persistent
= 1
69 * -----------------------------------------------------------------------------
70 * structure definitions
71 * -----------------------------------------------------------------------------
74 typedef struct rigidbody rigidbody
;
75 typedef struct rb_object rb_object
;
76 typedef struct contact rb_ct
;
77 typedef struct rb_sphere rb_sphere
;
78 typedef struct rb_capsule rb_capsule
;
79 typedef struct rb_scene rb_scene
;
104 /* inertia model and inverse world tensor */
107 m4x3f to_world
, to_local
;
116 k_rb_shape_sphere
= 1,
117 k_rb_shape_capsule
= 2,
124 struct rb_sphere sphere
;
125 struct rb_capsule capsule
;
126 struct rb_scene scene
;
131 VG_STATIC
struct contact
133 rigidbody
*rba
, *rbb
;
136 float p
, bias
, norm_impulse
, tangent_impulse
[2],
137 normal_mass
, tangent_mass
[2];
141 enum contact_type type
;
143 rb_contact_buffer
[256];
144 VG_STATIC
int rb_contact_count
= 0;
146 typedef struct rb_constr_pos rb_constr_pos
;
147 typedef struct rb_constr_swingtwist rb_constr_swingtwist
;
151 rigidbody
*rba
, *rbb
;
155 struct rb_constr_swingtwist
157 rigidbody
*rba
, *rbb
;
159 v4f conevx
, conevy
; /* relative to rba */
160 v3f view_offset
, /* relative to rba */
161 coneva
, conevxb
;/* relative to rbb */
163 int tangent_violation
, axis_violation
;
164 v3f axis
, tangent_axis
, tangent_target
, axis_target
;
167 float tangent_mass
, axis_mass
;
170 struct rb_constr_spring
176 * -----------------------------------------------------------------------------
178 * -----------------------------------------------------------------------------
181 VG_STATIC
float sphere_volume( float radius
)
183 float r3
= radius
*radius
*radius
;
184 return (4.0f
/3.0f
) * VG_PIf
* r3
;
187 VG_STATIC
void rb_tangent_basis( v3f n
, v3f tx
, v3f ty
)
189 /* Compute tangent basis (box2d) */
190 if( fabsf( n
[0] ) >= 0.57735027f
)
204 v3_cross( n
, tx
, ty
);
208 * -----------------------------------------------------------------------------
210 * -----------------------------------------------------------------------------
213 VG_STATIC
void rb_debug_contact( rb_ct
*ct
)
216 v3_muladds( ct
->co
, ct
->n
, 0.05f
, p1
);
218 if( ct
->type
== k_contact_type_default
)
220 vg_line_pt3( ct
->co
, 0.0125f
, 0xff0000ff );
221 vg_line( ct
->co
, p1
, 0xffffffff );
223 else if( ct
->type
== k_contact_type_edge
)
225 vg_line_pt3( ct
->co
, 0.0125f
, 0xff00ffc0 );
226 vg_line( ct
->co
, p1
, 0xffffffff );
230 VG_STATIC
void debug_sphere( m4x3f m
, float radius
, u32 colour
)
232 v3f ly
= { 0.0f
, 0.0f
, radius
},
233 lx
= { 0.0f
, radius
, 0.0f
},
234 lz
= { 0.0f
, 0.0f
, radius
};
236 for( int i
=0; i
<16; i
++ )
238 float t
= ((float)(i
+1) * (1.0f
/16.0f
)) * VG_PIf
* 2.0f
,
242 v3f py
= { s
*radius
, 0.0f
, c
*radius
},
243 px
= { s
*radius
, c
*radius
, 0.0f
},
244 pz
= { 0.0f
, s
*radius
, c
*radius
};
246 v3f p0
, p1
, p2
, p3
, p4
, p5
;
247 m4x3_mulv( m
, py
, p0
);
248 m4x3_mulv( m
, ly
, p1
);
249 m4x3_mulv( m
, px
, p2
);
250 m4x3_mulv( m
, lx
, p3
);
251 m4x3_mulv( m
, pz
, p4
);
252 m4x3_mulv( m
, lz
, p5
);
254 vg_line( p0
, p1
, colour
== 0x00? 0xff00ff00: colour
);
255 vg_line( p2
, p3
, colour
== 0x00? 0xff0000ff: colour
);
256 vg_line( p4
, p5
, colour
== 0x00? 0xffff0000: colour
);
264 VG_STATIC
void debug_capsule( m4x3f m
, float radius
, float h
, u32 colour
)
266 v3f ly
= { 0.0f
, 0.0f
, radius
},
267 lx
= { 0.0f
, radius
, 0.0f
},
268 lz
= { 0.0f
, 0.0f
, radius
};
270 float s0
= sinf(0.0f
)*radius
,
271 c0
= cosf(0.0f
)*radius
;
273 v3f p0
, p1
, up
, right
, forward
;
274 m3x3_mulv( m
, (v3f
){0.0f
,1.0f
,0.0f
}, up
);
275 m3x3_mulv( m
, (v3f
){1.0f
,0.0f
,0.0f
}, right
);
276 m3x3_mulv( m
, (v3f
){0.0f
,0.0f
,-1.0f
}, forward
);
277 v3_muladds( m
[3], up
, -h
*0.5f
+radius
, p0
);
278 v3_muladds( m
[3], up
, h
*0.5f
-radius
, p1
);
281 v3_muladds( p0
, right
, radius
, a0
);
282 v3_muladds( p1
, right
, radius
, a1
);
283 v3_muladds( p0
, forward
, radius
, b0
);
284 v3_muladds( p1
, forward
, radius
, b1
);
285 vg_line( a0
, a1
, colour
);
286 vg_line( b0
, b1
, colour
);
288 v3_muladds( p0
, right
, -radius
, a0
);
289 v3_muladds( p1
, right
, -radius
, a1
);
290 v3_muladds( p0
, forward
, -radius
, b0
);
291 v3_muladds( p1
, forward
, -radius
, b1
);
292 vg_line( a0
, a1
, colour
);
293 vg_line( b0
, b1
, colour
);
295 for( int i
=0; i
<16; i
++ )
297 float t
= ((float)(i
+1) * (1.0f
/16.0f
)) * VG_PIf
* 2.0f
,
301 v3f e0
= { s0
, 0.0f
, c0
},
302 e1
= { s1
, 0.0f
, c1
},
303 e2
= { s0
, c0
, 0.0f
},
304 e3
= { s1
, c1
, 0.0f
},
305 e4
= { 0.0f
, c0
, s0
},
306 e5
= { 0.0f
, c1
, s1
};
308 m3x3_mulv( m
, e0
, e0
);
309 m3x3_mulv( m
, e1
, e1
);
310 m3x3_mulv( m
, e2
, e2
);
311 m3x3_mulv( m
, e3
, e3
);
312 m3x3_mulv( m
, e4
, e4
);
313 m3x3_mulv( m
, e5
, e5
);
315 v3_add( p0
, e0
, a0
);
316 v3_add( p0
, e1
, a1
);
317 v3_add( p1
, e0
, b0
);
318 v3_add( p1
, e1
, b1
);
320 vg_line( a0
, a1
, colour
);
321 vg_line( b0
, b1
, colour
);
325 v3_add( p0
, e2
, a0
);
326 v3_add( p0
, e3
, a1
);
327 v3_add( p0
, e4
, b0
);
328 v3_add( p0
, e5
, b1
);
332 v3_add( p1
, e2
, a0
);
333 v3_add( p1
, e3
, a1
);
334 v3_add( p1
, e4
, b0
);
335 v3_add( p1
, e5
, b1
);
338 vg_line( a0
, a1
, colour
);
339 vg_line( b0
, b1
, colour
);
346 VG_STATIC
void rb_object_debug( rb_object
*obj
, u32 colour
)
348 if( obj
->type
== k_rb_shape_box
){
349 v3f
*box
= obj
->rb
.bbx
;
350 vg_line_boxf_transformed( obj
->rb
.to_world
, obj
->rb
.bbx
, colour
);
352 else if( obj
->type
== k_rb_shape_sphere
){
353 debug_sphere( obj
->rb
.to_world
, obj
->inf
.sphere
.radius
, colour
);
355 else if( obj
->type
== k_rb_shape_capsule
){
357 float h
= obj
->inf
.capsule
.height
,
358 r
= obj
->inf
.capsule
.radius
;
360 debug_capsule( obj
->rb
.to_world
, r
, h
, colour
);
362 else if( obj
->type
== k_rb_shape_scene
){
363 vg_line_boxf( obj
->rb
.bbx
, colour
);
368 * -----------------------------------------------------------------------------
370 * -----------------------------------------------------------------------------
374 * Update world space bounding box based on local one
376 VG_STATIC
void rb_update_bounds( rigidbody
*rb
)
378 box_copy( rb
->bbx
, rb
->bbx_world
);
379 m4x3_transform_aabb( rb
->to_world
, rb
->bbx_world
);
383 * Commit transform to rigidbody. Updates matrices
385 VG_STATIC
void rb_update_transform( rigidbody
*rb
)
387 q_normalize( rb
->q
);
388 q_m3x3( rb
->q
, rb
->to_world
);
389 v3_copy( rb
->co
, rb
->to_world
[3] );
391 m4x3_invert_affine( rb
->to_world
, rb
->to_local
);
394 m3x3_mulv( rb
->to_world
, (v3f
){1.0f
,0.0f
, 0.0f
}, rb
->right
);
395 m3x3_mulv( rb
->to_world
, (v3f
){0.0f
,1.0f
, 0.0f
}, rb
->up
);
396 m3x3_mulv( rb
->to_world
, (v3f
){0.0f
,0.0f
,-1.0f
}, rb
->forward
);
399 m3x3_mul( rb
->iI
, rb
->to_local
, rb
->iIw
);
400 m3x3_mul( rb
->to_world
, rb
->iIw
, rb
->iIw
);
402 rb_update_bounds( rb
);
406 * Extrapolate rigidbody into a transform based on vg accumulator.
407 * Useful for rendering
409 VG_STATIC
void rb_extrapolate( rigidbody
*rb
, v3f co
, v4f q
)
411 float substep
= vg_clampf( vg
.accumulator
/ k_rb_delta
, 0.0f
, 1.0f
);
413 v3_muladds( rb
->co
, rb
->v
, k_rb_delta
*substep
, co
);
415 if( v3_length2( rb
->w
) > 0.0f
){
418 v3_copy( rb
->w
, axis
);
420 float mag
= v3_length( axis
);
421 v3_divs( axis
, mag
, axis
);
422 q_axis_angle( rotation
, axis
, mag
*k_rb_delta
*substep
);
423 q_mul( rotation
, rb
->q
, q
);
432 * Initialize rigidbody and calculate masses, inertia
434 VG_STATIC
void rb_init_object( rb_object
*obj
)
439 if( obj
->type
== k_rb_shape_box
){
441 v3_sub( obj
->rb
.bbx
[1], obj
->rb
.bbx
[0], dims
);
442 volume
= dims
[0]*dims
[1]*dims
[2];
444 else if( obj
->type
== k_rb_shape_sphere
){
445 volume
= sphere_volume( obj
->inf
.sphere
.radius
);
446 v3_fill( obj
->rb
.bbx
[0], -obj
->inf
.sphere
.radius
);
447 v3_fill( obj
->rb
.bbx
[1], obj
->inf
.sphere
.radius
);
449 else if( obj
->type
== k_rb_shape_capsule
){
450 float r
= obj
->inf
.capsule
.radius
,
451 h
= obj
->inf
.capsule
.height
;
452 volume
= sphere_volume( r
) + VG_PIf
* r
*r
* (h
- r
*2.0f
);
454 v3_fill( obj
->rb
.bbx
[0], -r
);
455 v3_fill( obj
->rb
.bbx
[1], r
);
456 obj
->rb
.bbx
[0][1] = -h
;
457 obj
->rb
.bbx
[1][1] = h
;
459 else if( obj
->type
== k_rb_shape_scene
){
461 box_copy( obj
->inf
.scene
.bh_scene
->nodes
[0].bbx
, obj
->rb
.bbx
);
465 obj
->rb
.inv_mass
= 0.0f
;
466 v3_zero( obj
->rb
.I
);
467 m3x3_zero( obj
->rb
.iI
);
470 float mass
= 2.0f
*volume
;
471 obj
->rb
.inv_mass
= 1.0f
/mass
;
474 v3_sub( obj
->rb
.bbx
[1], obj
->rb
.bbx
[0], extent
);
475 v3_muls( extent
, 0.5f
, extent
);
477 /* local intertia tensor */
478 float scale
= k_inertia_scale
;
479 float ex2
= scale
*extent
[0]*extent
[0],
480 ey2
= scale
*extent
[1]*extent
[1],
481 ez2
= scale
*extent
[2]*extent
[2];
483 obj
->rb
.I
[0] = ((1.0f
/12.0f
) * mass
* (ey2
+ez2
));
484 obj
->rb
.I
[1] = ((1.0f
/12.0f
) * mass
* (ex2
+ez2
));
485 obj
->rb
.I
[2] = ((1.0f
/12.0f
) * mass
* (ex2
+ey2
));
487 m3x3_identity( obj
->rb
.iI
);
488 obj
->rb
.iI
[0][0] = obj
->rb
.I
[0];
489 obj
->rb
.iI
[1][1] = obj
->rb
.I
[1];
490 obj
->rb
.iI
[2][2] = obj
->rb
.I
[2];
491 m3x3_inv( obj
->rb
.iI
, obj
->rb
.iI
);
494 rb_update_transform( &obj
->rb
);
497 VG_STATIC
void rb_iter( rigidbody
*rb
)
499 if( !vg_validf( rb
->v
[0] ) ||
500 !vg_validf( rb
->v
[1] ) ||
501 !vg_validf( rb
->v
[2] ) )
503 vg_fatal_exit_loop( "NaN velocity" );
506 v3f gravity
= { 0.0f
, -9.8f
, 0.0f
};
507 v3_muladds( rb
->v
, gravity
, k_rb_delta
, rb
->v
);
509 /* intergrate velocity */
510 v3_muladds( rb
->co
, rb
->v
, k_rb_delta
, rb
->co
);
511 v3_lerp( rb
->w
, (v3f
){0.0f
,0.0f
,0.0f
}, 0.0025f
, rb
->w
);
513 /* inegrate inertia */
514 if( v3_length2( rb
->w
) > 0.0f
)
518 v3_copy( rb
->w
, axis
);
520 float mag
= v3_length( axis
);
521 v3_divs( axis
, mag
, axis
);
522 q_axis_angle( rotation
, axis
, mag
*k_rb_delta
);
523 q_mul( rotation
, rb
->q
, rb
->q
);
527 v3_muls( rb
->v
, 1.0f
/(1.0f
+k_rb_delta
*k_damp_linear
), rb
->v
);
528 v3_muls( rb
->w
, 1.0f
/(1.0f
+k_rb_delta
*k_damp_angular
), rb
->w
);
533 * -----------------------------------------------------------------------------
534 * Boolean shape overlap functions
535 * -----------------------------------------------------------------------------
539 * Project AABB, and triangle interval onto axis to check if they overlap
541 VG_STATIC
int rb_box_triangle_interval( v3f extent
, v3f axis
, v3f tri
[3] )
545 r
= extent
[0] * fabsf(axis
[0]) +
546 extent
[1] * fabsf(axis
[1]) +
547 extent
[2] * fabsf(axis
[2]),
549 p0
= v3_dot( axis
, tri
[0] ),
550 p1
= v3_dot( axis
, tri
[1] ),
551 p2
= v3_dot( axis
, tri
[2] ),
553 e
= vg_maxf(-vg_maxf(p0
,vg_maxf(p1
,p2
)), vg_minf(p0
,vg_minf(p1
,p2
)));
555 if( e
> r
) return 0;
560 * Seperating axis test box vs triangle
562 VG_STATIC
int rb_box_triangle_sat( v3f extent
, v3f center
,
563 m4x3f to_local
, v3f tri_src
[3] )
567 for( int i
=0; i
<3; i
++ ){
568 m4x3_mulv( to_local
, tri_src
[i
], tri
[i
] );
569 v3_sub( tri
[i
], center
, tri
[i
] );
573 v3_sub( tri
[1], tri
[0], f0
);
574 v3_sub( tri
[2], tri
[1], f1
);
575 v3_sub( tri
[0], tri
[2], f2
);
579 v3_cross( (v3f
){1.0f
,0.0f
,0.0f
}, f0
, axis
[0] );
580 v3_cross( (v3f
){1.0f
,0.0f
,0.0f
}, f1
, axis
[1] );
581 v3_cross( (v3f
){1.0f
,0.0f
,0.0f
}, f2
, axis
[2] );
582 v3_cross( (v3f
){0.0f
,1.0f
,0.0f
}, f0
, axis
[3] );
583 v3_cross( (v3f
){0.0f
,1.0f
,0.0f
}, f1
, axis
[4] );
584 v3_cross( (v3f
){0.0f
,1.0f
,0.0f
}, f2
, axis
[5] );
585 v3_cross( (v3f
){0.0f
,0.0f
,1.0f
}, f0
, axis
[6] );
586 v3_cross( (v3f
){0.0f
,0.0f
,1.0f
}, f1
, axis
[7] );
587 v3_cross( (v3f
){0.0f
,0.0f
,1.0f
}, f2
, axis
[8] );
589 for( int i
=0; i
<9; i
++ )
590 if(!rb_box_triangle_interval( extent
, axis
[i
], tri
)) return 0;
593 if(!rb_box_triangle_interval( extent
, (v3f
){1.0f
,0.0f
,0.0f
}, tri
)) return 0;
594 if(!rb_box_triangle_interval( extent
, (v3f
){0.0f
,1.0f
,0.0f
}, tri
)) return 0;
595 if(!rb_box_triangle_interval( extent
, (v3f
){0.0f
,0.0f
,1.0f
}, tri
)) return 0;
598 v3_cross( f0
, f1
, n
);
599 if(!rb_box_triangle_interval( extent
, n
, tri
)) return 0;
605 * -----------------------------------------------------------------------------
607 * -----------------------------------------------------------------------------
610 VG_STATIC
int rb_manifold_apply_filtered( rb_ct
*man
, int len
)
614 for( int i
=0; i
<len
; i
++ ){
617 if( ct
->type
== k_contact_type_disabled
)
627 * Merge two contacts if they are within radius(r) of eachother
629 VG_STATIC
void rb_manifold_contact_weld( rb_ct
*ci
, rb_ct
*cj
, float r
)
631 if( v3_dist2( ci
->co
, cj
->co
) < r
*r
){
632 cj
->type
= k_contact_type_disabled
;
633 ci
->p
= (ci
->p
+ cj
->p
) * 0.5f
;
635 v3_add( ci
->co
, cj
->co
, ci
->co
);
636 v3_muls( ci
->co
, 0.5f
, ci
->co
);
639 v3_sub( ci
->rba
->co
, ci
->co
, delta
);
641 float c0
= v3_dot( ci
->n
, delta
),
642 c1
= v3_dot( cj
->n
, delta
);
644 if( c0
< 0.0f
|| c1
< 0.0f
){
646 ci
->type
= k_contact_type_disabled
;
650 v3_muls( ci
->n
, c0
, n
);
651 v3_muladds( n
, cj
->n
, c1
, n
);
661 VG_STATIC
void rb_manifold_filter_joint_edges( rb_ct
*man
, int len
, float r
)
663 for( int i
=0; i
<len
-1; i
++ ){
665 if( ci
->type
!= k_contact_type_edge
)
668 for( int j
=i
+1; j
<len
; j
++ ){
670 if( cj
->type
!= k_contact_type_edge
)
673 rb_manifold_contact_weld( ci
, cj
, r
);
679 * Resolve overlapping pairs
683 VG_STATIC
void rb_manifold_filter_pairs( rb_ct
*man
, int len
, float r
)
685 for( int i
=0; i
<len
-1; i
++ ){
689 if( ci
->type
== k_contact_type_disabled
) continue;
691 for( int j
=i
+1; j
<len
; j
++ ){
694 if( cj
->type
== k_contact_type_disabled
) continue;
696 if( v3_dist2( ci
->co
, cj
->co
) < r
*r
){
697 cj
->type
= k_contact_type_disabled
;
698 v3_add( cj
->n
, ci
->n
, ci
->n
);
705 float n
= 1.0f
/((float)similar
+1.0f
);
706 v3_muls( ci
->n
, n
, ci
->n
);
709 if( v3_length2(ci
->n
) < 0.1f
*0.1f
)
710 ci
->type
= k_contact_type_disabled
;
712 v3_normalize( ci
->n
);
718 * Remove contacts that are facing away from A
720 VG_STATIC
void rb_manifold_filter_backface( rb_ct
*man
, int len
)
722 for( int i
=0; i
<len
; i
++ ){
724 if( ct
->type
== k_contact_type_disabled
)
728 v3_sub( ct
->co
, ct
->rba
->co
, delta
);
730 if( v3_dot( delta
, ct
->n
) > -0.001f
)
731 ct
->type
= k_contact_type_disabled
;
736 * Filter out duplicate coplanar results. Good for spheres.
738 VG_STATIC
void rb_manifold_filter_coplanar( rb_ct
*man
, int len
, float w
)
740 for( int i
=0; i
<len
; i
++ ){
742 if( ci
->type
== k_contact_type_disabled
||
743 ci
->type
== k_contact_type_edge
)
746 float d1
= v3_dot( ci
->co
, ci
->n
);
748 for( int j
=0; j
<len
; j
++ ){
753 if( cj
->type
== k_contact_type_disabled
)
756 float d2
= v3_dot( cj
->co
, ci
->n
),
759 if( fabsf( d
) <= w
){
760 cj
->type
= k_contact_type_disabled
;
767 * -----------------------------------------------------------------------------
769 * -----------------------------------------------------------------------------
775 * These do not automatically allocate contacts, an appropriately sized
776 * buffer must be supplied. The function returns the size of the manifold
777 * which was generated.
779 * The values set on the contacts are: n, co, p, rba, rbb
783 * By collecting the minimum(time) and maximum(time) pairs of points, we
784 * build a reduced and stable exact manifold.
787 * rx: minimum distance of these points
788 * dx: the delta between the two points
790 * pairs will only ammend these if they are creating a collision
792 typedef struct capsule_manifold capsule_manifold
;
793 struct capsule_manifold
801 * Expand a line manifold with a new pair. t value is the time along segment
802 * on the oriented object which created this pair.
804 VG_STATIC
void rb_capsule_manifold( v3f pa
, v3f pb
, float t
, float r
,
805 capsule_manifold
*manifold
)
808 v3_sub( pa
, pb
, delta
);
810 if( v3_length2(delta
) < r
*r
){
811 if( t
< manifold
->t0
){
812 v3_copy( delta
, manifold
->d0
);
817 if( t
> manifold
->t1
){
818 v3_copy( delta
, manifold
->d1
);
825 VG_STATIC
void rb_capsule_manifold_init( capsule_manifold
*manifold
)
827 manifold
->t0
= INFINITY
;
828 manifold
->t1
= -INFINITY
;
831 VG_STATIC
int rb_capsule__manifold_done( m4x3f mtx
, rb_capsule
*c
,
832 capsule_manifold
*manifold
,
836 v3_muladds( mtx
[3], mtx
[1], -c
->height
*0.5f
+c
->radius
, p0
);
837 v3_muladds( mtx
[3], mtx
[1], c
->height
*0.5f
-c
->radius
, p1
);
840 if( manifold
->t0
<= 1.0f
){
844 v3_muls( p0
, 1.0f
-manifold
->t0
, pa
);
845 v3_muladds( pa
, p1
, manifold
->t0
, pa
);
847 float d
= v3_length( manifold
->d0
);
848 v3_muls( manifold
->d0
, 1.0f
/d
, ct
->n
);
849 v3_muladds( pa
, ct
->n
, -c
->radius
, ct
->co
);
851 ct
->p
= manifold
->r0
- d
;
852 ct
->type
= k_contact_type_default
;
856 if( (manifold
->t1
>= 0.0f
) && (manifold
->t0
!= manifold
->t1
) ){
857 rb_ct
*ct
= buf
+count
;
860 v3_muls( p0
, 1.0f
-manifold
->t1
, pa
);
861 v3_muladds( pa
, p1
, manifold
->t1
, pa
);
863 float d
= v3_length( manifold
->d1
);
864 v3_muls( manifold
->d1
, 1.0f
/d
, ct
->n
);
865 v3_muladds( pa
, ct
->n
, -c
->radius
, ct
->co
);
867 ct
->p
= manifold
->r1
- d
;
868 ct
->type
= k_contact_type_default
;
878 vg_line( buf
[0].co
, buf
[1].co
, 0xff0000ff );
883 VG_STATIC
int rb_capsule_sphere( rb_object
*obja
, rb_object
*objb
, rb_ct
*buf
)
885 rigidbody
*rba
= &obja
->rb
, *rbb
= &objb
->rb
;
886 float h
= obja
->inf
.capsule
.height
,
887 ra
= obja
->inf
.capsule
.radius
,
888 rb
= objb
->inf
.sphere
.radius
;
891 v3_muladds( rba
->co
, rba
->to_world
[1], -h
*0.5f
+ra
, p0
);
892 v3_muladds( rba
->co
, rba
->to_world
[1], h
*0.5f
-ra
, p1
);
895 closest_point_segment( p0
, p1
, rbb
->co
, c
);
896 v3_sub( c
, rbb
->co
, delta
);
898 float d2
= v3_length2(delta
),
905 v3_muls( delta
, 1.0f
/d
, ct
->n
);
909 v3_muladds( c
, ct
->n
, -ra
, p0
);
910 v3_muladds( rbb
->co
, ct
->n
, rb
, p1
);
911 v3_add( p0
, p1
, ct
->co
);
912 v3_muls( ct
->co
, 0.5f
, ct
->co
);
916 ct
->type
= k_contact_type_default
;
924 VG_STATIC
int rb_capsule__capsule( m4x3f mtxA
, rb_capsule
*ca
,
925 m4x3f mtxB
, rb_capsule
*cb
, rb_ct
*buf
)
927 float ha
= ca
->height
,
934 v3_muladds( mtxA
[3], mtxA
[1], -ha
*0.5f
+ra
, p0
);
935 v3_muladds( mtxA
[3], mtxA
[1], ha
*0.5f
-ra
, p1
);
936 v3_muladds( mtxB
[3], mtxB
[1], -hb
*0.5f
+rb
, p2
);
937 v3_muladds( mtxB
[3], mtxB
[1], hb
*0.5f
-rb
, p3
);
939 capsule_manifold manifold
;
940 rb_capsule_manifold_init( &manifold
);
944 closest_segment_segment( p0
, p1
, p2
, p3
, &ta
, &tb
, pa
, pb
);
945 rb_capsule_manifold( pa
, pb
, ta
, r
, &manifold
);
947 ta
= closest_point_segment( p0
, p1
, p2
, pa
);
948 tb
= closest_point_segment( p0
, p1
, p3
, pb
);
949 rb_capsule_manifold( pa
, p2
, ta
, r
, &manifold
);
950 rb_capsule_manifold( pb
, p3
, tb
, r
, &manifold
);
952 closest_point_segment( p2
, p3
, p0
, pa
);
953 closest_point_segment( p2
, p3
, p1
, pb
);
954 rb_capsule_manifold( p0
, pa
, 0.0f
, r
, &manifold
);
955 rb_capsule_manifold( p1
, pb
, 1.0f
, r
, &manifold
);
957 return rb_capsule__manifold_done( mtxA
, ca
, &manifold
, buf
);
962 * Generates up to two contacts; optimised for the most stable manifold
964 VG_STATIC
int rb_capsule_box( rigidbody
*rba
, rigidbody
*rbb
, rb_ct
*buf
)
966 float h
= rba
->inf
.capsule
.height
,
967 r
= rba
->inf
.capsule
.radius
;
970 * Solving this in symetric local space of the cube saves us some time and a
971 * couple branches when it comes to the quad stage.
974 v3_add( rbb
->bbx
[0], rbb
->bbx
[1], centroid
);
975 v3_muls( centroid
, 0.5f
, centroid
);
978 v3_sub( rbb
->bbx
[0], centroid
, bbx
[0] );
979 v3_sub( rbb
->bbx
[1], centroid
, bbx
[1] );
981 v3f pc
, p0w
, p1w
, p0
, p1
;
982 v3_muladds( rba
->co
, rba
->up
, -h
*0.5f
+r
, p0w
);
983 v3_muladds( rba
->co
, rba
->up
, h
*0.5f
-r
, p1w
);
985 m4x3_mulv( rbb
->to_local
, p0w
, p0
);
986 m4x3_mulv( rbb
->to_local
, p1w
, p1
);
987 v3_sub( p0
, centroid
, p0
);
988 v3_sub( p1
, centroid
, p1
);
989 v3_add( p0
, p1
, pc
);
990 v3_muls( pc
, 0.5f
, pc
);
993 * Finding an appropriate quad to collide lines with
996 v3_div( pc
, bbx
[1], region
);
999 if( (fabsf(region
[0]) > fabsf(region
[1])) &&
1000 (fabsf(region
[0]) > fabsf(region
[2])) )
1002 float px
= vg_signf(region
[0]) * bbx
[1][0];
1003 v3_copy( (v3f
){ px
, bbx
[0][1], bbx
[0][2] }, quad
[0] );
1004 v3_copy( (v3f
){ px
, bbx
[1][1], bbx
[0][2] }, quad
[1] );
1005 v3_copy( (v3f
){ px
, bbx
[1][1], bbx
[1][2] }, quad
[2] );
1006 v3_copy( (v3f
){ px
, bbx
[0][1], bbx
[1][2] }, quad
[3] );
1008 else if( fabsf(region
[1]) > fabsf(region
[2]) )
1010 float py
= vg_signf(region
[1]) * bbx
[1][1];
1011 v3_copy( (v3f
){ bbx
[0][0], py
, bbx
[0][2] }, quad
[0] );
1012 v3_copy( (v3f
){ bbx
[1][0], py
, bbx
[0][2] }, quad
[1] );
1013 v3_copy( (v3f
){ bbx
[1][0], py
, bbx
[1][2] }, quad
[2] );
1014 v3_copy( (v3f
){ bbx
[0][0], py
, bbx
[1][2] }, quad
[3] );
1018 float pz
= vg_signf(region
[2]) * bbx
[1][2];
1019 v3_copy( (v3f
){ bbx
[0][0], bbx
[0][1], pz
}, quad
[0] );
1020 v3_copy( (v3f
){ bbx
[1][0], bbx
[0][1], pz
}, quad
[1] );
1021 v3_copy( (v3f
){ bbx
[1][0], bbx
[1][1], pz
}, quad
[2] );
1022 v3_copy( (v3f
){ bbx
[0][0], bbx
[1][1], pz
}, quad
[3] );
1025 capsule_manifold manifold
;
1026 rb_capsule_manifold_init( &manifold
);
1029 closest_point_aabb( p0
, bbx
, c0
);
1030 closest_point_aabb( p1
, bbx
, c1
);
1033 v3_sub( c0
, p0
, d0
);
1034 v3_sub( c1
, p1
, d1
);
1035 v3_sub( p1
, p0
, da
);
1041 if( v3_dot( da
, d0
) <= 0.01f
)
1042 rb_capsule_manifold( p0
, c0
, 0.0f
, r
, &manifold
);
1044 if( v3_dot( da
, d1
) >= -0.01f
)
1045 rb_capsule_manifold( p1
, c1
, 1.0f
, r
, &manifold
);
1047 for( int i
=0; i
<4; i
++ )
1054 closest_segment_segment( p0
, p1
, quad
[i0
], quad
[i1
], &ta
, &tb
, ca
, cb
);
1055 rb_capsule_manifold( ca
, cb
, ta
, r
, &manifold
);
1059 * Create final contacts based on line manifold
1061 m3x3_mulv( rbb
->to_world
, manifold
.d0
, manifold
.d0
);
1062 m3x3_mulv( rbb
->to_world
, manifold
.d1
, manifold
.d1
);
1069 for( int i
=0; i
<4; i
++ )
1075 v3_add( quad
[i0
], centroid
, q0
);
1076 v3_add( quad
[i1
], centroid
, q1
);
1078 m4x3_mulv( rbb
->to_world
, q0
, q0
);
1079 m4x3_mulv( rbb
->to_world
, q1
, q1
);
1081 vg_line( q0
, q1
, 0xffffffff );
1085 return rb_capsule_manifold_done( rba
, rbb
, &manifold
, buf
);
1089 VG_STATIC
int rb_sphere_box( rb_object
*obja
, rb_object
*objb
, rb_ct
*buf
)
1092 rigidbody
*rba
= &obja
->rb
, *rbb
= &objb
->rb
;
1094 closest_point_obb( rba
->co
, rbb
->bbx
, rbb
->to_world
, rbb
->to_local
, co
);
1095 v3_sub( rba
->co
, co
, delta
);
1097 float d2
= v3_length2(delta
),
1098 r
= obja
->inf
.sphere
.radius
;
1104 if( d2
<= 0.0001f
){
1105 v3_sub( rba
->co
, rbb
->co
, delta
);
1108 * some extra testing is required to find the best axis to push the
1109 * object back outside the box. Since there isnt a clear seperating
1110 * vector already, especially on really high aspect boxes.
1112 float lx
= v3_dot( rbb
->to_world
[0], delta
),
1113 ly
= v3_dot( rbb
->to_world
[1], delta
),
1114 lz
= v3_dot( rbb
->to_world
[2], delta
),
1115 px
= rbb
->bbx
[1][0] - fabsf(lx
),
1116 py
= rbb
->bbx
[1][1] - fabsf(ly
),
1117 pz
= rbb
->bbx
[1][2] - fabsf(lz
);
1119 if( px
< py
&& px
< pz
)
1120 v3_muls( rbb
->to_world
[0], vg_signf(lx
), ct
->n
);
1122 v3_muls( rbb
->to_world
[1], vg_signf(ly
), ct
->n
);
1124 v3_muls( rbb
->to_world
[2], vg_signf(lz
), ct
->n
);
1126 v3_muladds( rba
->co
, ct
->n
, -r
, ct
->co
);
1131 v3_muls( delta
, 1.0f
/d
, ct
->n
);
1133 v3_copy( co
, ct
->co
);
1138 ct
->type
= k_contact_type_default
;
1145 VG_STATIC
int rb_sphere_sphere( rb_object
*obja
, rb_object
*objb
, rb_ct
*buf
)
1147 rigidbody
*rba
= &obja
->rb
, *rbb
= &objb
->rb
;
1149 v3_sub( rba
->co
, rbb
->co
, delta
);
1151 float d2
= v3_length2(delta
),
1152 r
= obja
->inf
.sphere
.radius
+ objb
->inf
.sphere
.radius
;
1155 float d
= sqrtf(d2
);
1158 v3_muls( delta
, 1.0f
/d
, ct
->n
);
1161 v3_muladds( rba
->co
, ct
->n
,-obja
->inf
.sphere
.radius
, p0
);
1162 v3_muladds( rbb
->co
, ct
->n
, objb
->inf
.sphere
.radius
, p1
);
1163 v3_add( p0
, p1
, ct
->co
);
1164 v3_muls( ct
->co
, 0.5f
, ct
->co
);
1165 ct
->type
= k_contact_type_default
;
1175 //#define RIGIDBODY_DYNAMIC_MESH_EDGES
1178 __attribute__ ((deprecated
))
1179 VG_STATIC
int rb_sphere_triangle( rigidbody
*rba
, rigidbody
*rbb
,
1180 v3f tri
[3], rb_ct
*buf
)
1184 #ifdef RIGIDBODY_DYNAMIC_MESH_EDGES
1185 closest_on_triangle_1( rba
->co
, tri
, co
);
1187 enum contact_type type
= closest_on_triangle_1( rba
->co
, tri
, co
);
1190 v3_sub( rba
->co
, co
, delta
);
1192 float d2
= v3_length2( delta
),
1193 r
= rba
->inf
.sphere
.radius
;
1200 v3_sub( tri
[2], tri
[0], ab
);
1201 v3_sub( tri
[1], tri
[0], ac
);
1202 v3_cross( ac
, ab
, tn
);
1203 v3_copy( tn
, ct
->n
);
1205 if( v3_length2( ct
->n
) <= 0.00001f
)
1207 vg_error( "Zero area triangle!\n" );
1211 v3_normalize( ct
->n
);
1213 float d
= sqrtf(d2
);
1215 v3_copy( co
, ct
->co
);
1227 VG_STATIC
int rb_sphere__triangle( m4x3f mtxA
, rb_sphere
*b
,
1228 v3f tri
[3], rb_ct
*buf
)
1231 enum contact_type type
= closest_on_triangle_1( mtxA
[3], tri
, co
);
1233 v3_sub( mtxA
[3], co
, delta
);
1235 float d2
= v3_length2( delta
),
1242 v3_sub( tri
[2], tri
[0], ab
);
1243 v3_sub( tri
[1], tri
[0], ac
);
1244 v3_cross( ac
, ab
, tn
);
1245 v3_copy( tn
, ct
->n
);
1247 if( v3_length2( ct
->n
) <= 0.00001f
){
1248 vg_error( "Zero area triangle!\n" );
1252 v3_normalize( ct
->n
);
1254 float d
= sqrtf(d2
);
1256 v3_copy( co
, ct
->co
);
1265 VG_STATIC
int rb_sphere__scene( m4x3f mtxA
, rb_sphere
*b
,
1266 m4x3f mtxB
, rb_scene
*s
, rb_ct
*buf
)
1268 scene
*sc
= s
->bh_scene
->user
;
1271 bh_iter_init( 0, &it
);
1276 float r
= b
->radius
+ 0.1f
;
1278 v3_sub( mtxA
[3], (v3f
){ r
,r
,r
}, box
[0] );
1279 v3_add( mtxA
[3], (v3f
){ r
,r
,r
}, box
[1] );
1281 while( bh_next( s
->bh_scene
, &it
, box
, &idx
) ){
1282 u32
*ptri
= &sc
->arrindices
[ idx
*3 ];
1285 for( int j
=0; j
<3; j
++ )
1286 v3_copy( sc
->arrvertices
[ptri
[j
]].co
, tri
[j
] );
1288 buf
[ count
].element_id
= ptri
[0];
1290 vg_line( tri
[0],tri
[1],0x70ff6000 );
1291 vg_line( tri
[1],tri
[2],0x70ff6000 );
1292 vg_line( tri
[2],tri
[0],0x70ff6000 );
1294 int contact
= rb_sphere__triangle( mtxA
, b
, tri
, &buf
[count
] );
1298 vg_warn( "Exceeding sphere_vs_scene capacity. Geometry too dense!\n" );
1306 VG_STATIC
int rb_box__scene( m4x3f mtxA
, boxf bbx
,
1307 m4x3f mtxB
, rb_scene
*s
, rb_ct
*buf
)
1310 scene
*sc
= s
->bh_scene
->user
;
1314 v3_sub( bbx
[1], bbx
[0], extent
);
1315 v3_muls( extent
, 0.5f
, extent
);
1316 v3_add( bbx
[0], extent
, center
);
1318 float r
= v3_length(extent
);
1320 v3_fill( world_bbx
[0], -r
);
1321 v3_fill( world_bbx
[1], r
);
1322 for( int i
=0; i
<2; i
++ ){
1323 v3_add( center
, world_bbx
[i
], world_bbx
[i
] );
1324 v3_add( mtxA
[3], world_bbx
[i
], world_bbx
[i
] );
1328 m4x3_invert_affine( mtxA
, to_local
);
1331 bh_iter_init( 0, &it
);
1335 vg_line_boxf( world_bbx
, VG__RED
);
1337 while( bh_next( s
->bh_scene
, &it
, world_bbx
, &idx
) ){
1338 u32
*ptri
= &sc
->arrindices
[ idx
*3 ];
1340 for( int j
=0; j
<3; j
++ )
1341 v3_copy( sc
->arrvertices
[ptri
[j
]].co
, tri
[j
] );
1343 if( rb_box_triangle_sat( extent
, center
, to_local
, tri
) ){
1344 vg_line(tri
[0],tri
[1],0xff50ff00 );
1345 vg_line(tri
[1],tri
[2],0xff50ff00 );
1346 vg_line(tri
[2],tri
[0],0xff50ff00 );
1349 vg_line(tri
[0],tri
[1],0xff0000ff );
1350 vg_line(tri
[1],tri
[2],0xff0000ff );
1351 vg_line(tri
[2],tri
[0],0xff0000ff );
1356 v3_sub( tri
[1], tri
[0], v0
);
1357 v3_sub( tri
[2], tri
[0], v1
);
1358 v3_cross( v0
, v1
, n
);
1361 /* find best feature */
1362 float best
= v3_dot( mtxA
[0], n
);
1365 for( int i
=1; i
<3; i
++ ){
1366 float c
= v3_dot( mtxA
[i
], n
);
1368 if( fabsf(c
) > fabsf(best
) ){
1377 float px
= best
> 0.0f
? bbx
[0][0]: bbx
[1][0];
1378 manifold
[0][0] = px
;
1379 manifold
[0][1] = bbx
[0][1];
1380 manifold
[0][2] = bbx
[0][2];
1381 manifold
[1][0] = px
;
1382 manifold
[1][1] = bbx
[1][1];
1383 manifold
[1][2] = bbx
[0][2];
1384 manifold
[2][0] = px
;
1385 manifold
[2][1] = bbx
[1][1];
1386 manifold
[2][2] = bbx
[1][2];
1387 manifold
[3][0] = px
;
1388 manifold
[3][1] = bbx
[0][1];
1389 manifold
[3][2] = bbx
[1][2];
1391 else if( axis
== 1 ){
1392 float py
= best
> 0.0f
? bbx
[0][1]: bbx
[1][1];
1393 manifold
[0][0] = bbx
[0][0];
1394 manifold
[0][1] = py
;
1395 manifold
[0][2] = bbx
[0][2];
1396 manifold
[1][0] = bbx
[1][0];
1397 manifold
[1][1] = py
;
1398 manifold
[1][2] = bbx
[0][2];
1399 manifold
[2][0] = bbx
[1][0];
1400 manifold
[2][1] = py
;
1401 manifold
[2][2] = bbx
[1][2];
1402 manifold
[3][0] = bbx
[0][0];
1403 manifold
[3][1] = py
;
1404 manifold
[3][2] = bbx
[1][2];
1407 float pz
= best
> 0.0f
? bbx
[0][2]: bbx
[1][2];
1408 manifold
[0][0] = bbx
[0][0];
1409 manifold
[0][1] = bbx
[0][1];
1410 manifold
[0][2] = pz
;
1411 manifold
[1][0] = bbx
[1][0];
1412 manifold
[1][1] = bbx
[0][1];
1413 manifold
[1][2] = pz
;
1414 manifold
[2][0] = bbx
[1][0];
1415 manifold
[2][1] = bbx
[1][1];
1416 manifold
[2][2] = pz
;
1417 manifold
[3][0] = bbx
[0][0];
1418 manifold
[3][1] = bbx
[1][1];
1419 manifold
[3][2] = pz
;
1422 for( int j
=0; j
<4; j
++ )
1423 m4x3_mulv( mtxA
, manifold
[j
], manifold
[j
] );
1425 vg_line( manifold
[0], manifold
[1], 0xffffffff );
1426 vg_line( manifold
[1], manifold
[2], 0xffffffff );
1427 vg_line( manifold
[2], manifold
[3], 0xffffffff );
1428 vg_line( manifold
[3], manifold
[0], 0xffffffff );
1430 for( int j
=0; j
<4; j
++ ){
1431 rb_ct
*ct
= buf
+count
;
1433 v3_copy( manifold
[j
], ct
->co
);
1434 v3_copy( n
, ct
->n
);
1436 float l0
= v3_dot( tri
[0], n
),
1437 l1
= v3_dot( manifold
[j
], n
);
1439 ct
->p
= (l0
-l1
)*0.5f
;
1443 ct
->type
= k_contact_type_default
;
1453 scene
*sc
= s
->bh_scene
->user
;
1457 v3_sub( bbx
[1], bbx
[0], extent
);
1458 v3_muls( extent
, 0.5f
, extent
);
1459 v3_add( bbx
[0], extent
, center
);
1461 float r
= v3_length(extent
);
1463 v3_fill( world_bbx
[0], -r
);
1464 v3_fill( world_bbx
[1], r
);
1465 for( int i
=0; i
<2; i
++ ){
1466 v3_add( center
, world_bbx
[i
], world_bbx
[i
] );
1467 v3_add( mtxA
[3], world_bbx
[i
], world_bbx
[i
] );
1471 m4x3_invert_affine( mtxA
, to_local
);
1474 bh_iter_init( 0, &it
);
1478 vg_line_boxf( world_bbx
, VG__RED
);
1480 while( bh_next( s
->bh_scene
, &it
, world_bbx
, &idx
) ){
1481 u32
*ptri
= &sc
->arrindices
[ idx
*3 ];
1483 for( int j
=0; j
<3; j
++ )
1484 v3_copy( sc
->arrvertices
[ptri
[j
]].co
, tri
[j
] );
1486 vg_line( tri
[0],tri
[1],VG__BLACK
);
1487 vg_line( tri
[1],tri
[2],VG__BLACK
);
1488 vg_line( tri
[2],tri
[0],VG__BLACK
);
1491 u32 clip_length
= 0;
1497 VG_STATIC
int rb_capsule__triangle( m4x3f mtxA
, rb_capsule
*c
,
1498 v3f tri
[3], rb_ct
*buf
)
1501 v3_muladds( mtxA
[3], mtxA
[1], -c
->height
*0.5f
+c
->radius
, p0w
);
1502 v3_muladds( mtxA
[3], mtxA
[1], c
->height
*0.5f
-c
->radius
, p1w
);
1504 capsule_manifold manifold
;
1505 rb_capsule_manifold_init( &manifold
);
1508 closest_on_triangle_1( p0w
, tri
, c0
);
1509 closest_on_triangle_1( p1w
, tri
, c1
);
1512 v3_sub( c0
, p0w
, d0
);
1513 v3_sub( c1
, p1w
, d1
);
1514 v3_sub( p1w
, p0w
, da
);
1520 if( v3_dot( da
, d0
) <= 0.01f
)
1521 rb_capsule_manifold( p0w
, c0
, 0.0f
, c
->radius
, &manifold
);
1523 if( v3_dot( da
, d1
) >= -0.01f
)
1524 rb_capsule_manifold( p1w
, c1
, 1.0f
, c
->radius
, &manifold
);
1526 for( int i
=0; i
<3; i
++ ){
1532 closest_segment_segment( p0w
, p1w
, tri
[i0
], tri
[i1
], &ta
, &tb
, ca
, cb
);
1533 rb_capsule_manifold( ca
, cb
, ta
, c
->radius
, &manifold
);
1537 v3_sub( tri
[1], tri
[0], v0
);
1538 v3_sub( tri
[2], tri
[0], v1
);
1539 v3_cross( v0
, v1
, n
);
1542 int count
= rb_capsule__manifold_done( mtxA
, c
, &manifold
, buf
);
1543 for( int i
=0; i
<count
; i
++ )
1544 v3_copy( n
, buf
[i
].n
);
1549 /* mtxB is defined only for tradition; it is not used currently */
1550 VG_STATIC
int rb_capsule__scene( m4x3f mtxA
, rb_capsule
*c
,
1551 m4x3f mtxB
, rb_scene
*s
,
1555 bh_iter_init( 0, &it
);
1560 v3_sub( mtxA
[3], (v3f
){ c
->height
, c
->height
, c
->height
}, bbx
[0] );
1561 v3_add( mtxA
[3], (v3f
){ c
->height
, c
->height
, c
->height
}, bbx
[1] );
1563 scene
*sc
= s
->bh_scene
->user
;
1565 while( bh_next( s
->bh_scene
, &it
, bbx
, &idx
) ){
1566 u32
*ptri
= &sc
->arrindices
[ idx
*3 ];
1569 for( int j
=0; j
<3; j
++ )
1570 v3_copy( sc
->arrvertices
[ptri
[j
]].co
, tri
[j
] );
1572 buf
[ count
].element_id
= ptri
[0];
1574 int contact
= rb_capsule__triangle( mtxA
, c
, tri
, &buf
[count
] );
1578 vg_warn("Exceeding capsule_vs_scene capacity. Geometry too dense!\n");
1586 VG_STATIC
int rb_global_has_space( void )
1588 if( rb_contact_count
+ 16 > vg_list_size(rb_contact_buffer
) )
1594 VG_STATIC rb_ct
*rb_global_buffer( void )
1596 return &rb_contact_buffer
[ rb_contact_count
];
1600 * -----------------------------------------------------------------------------
1602 * -----------------------------------------------------------------------------
1605 VG_STATIC
void rb_solver_reset(void)
1607 rb_contact_count
= 0;
1610 VG_STATIC rb_ct
*rb_global_ct(void)
1612 return rb_contact_buffer
+ rb_contact_count
;
1615 VG_STATIC
void rb_prepare_contact( rb_ct
*ct
, float timestep
)
1617 ct
->bias
= -0.2f
* (timestep
*3600.0f
)
1618 * vg_minf( 0.0f
, -ct
->p
+k_penetration_slop
);
1620 rb_tangent_basis( ct
->n
, ct
->t
[0], ct
->t
[1] );
1621 ct
->norm_impulse
= 0.0f
;
1622 ct
->tangent_impulse
[0] = 0.0f
;
1623 ct
->tangent_impulse
[1] = 0.0f
;
1626 /* calculate total move. manifold should belong to ONE object only */
1627 VG_STATIC
void rb_depenetrate( rb_ct
*manifold
, int len
, v3f dt
)
1631 for( int j
=0; j
<7; j
++ )
1633 for( int i
=0; i
<len
; i
++ )
1635 struct contact
*ct
= &manifold
[i
];
1637 float resolved_amt
= v3_dot( ct
->n
, dt
),
1638 remaining
= (ct
->p
-k_penetration_slop
) - resolved_amt
,
1639 apply
= vg_maxf( remaining
, 0.0f
) * 0.4f
;
1641 v3_muladds( dt
, ct
->n
, apply
, dt
);
1647 * Initializing things like tangent vectors
1649 VG_STATIC
void rb_presolve_contacts( rb_ct
*buffer
, int len
)
1651 for( int i
=0; i
<len
; i
++ ){
1652 rb_ct
*ct
= &buffer
[i
];
1653 rb_prepare_contact( ct
, k_rb_delta
);
1655 v3f ra
, rb
, raCn
, rbCn
, raCt
, rbCt
;
1656 v3_sub( ct
->co
, ct
->rba
->co
, ra
);
1657 v3_sub( ct
->co
, ct
->rbb
->co
, rb
);
1658 v3_cross( ra
, ct
->n
, raCn
);
1659 v3_cross( rb
, ct
->n
, rbCn
);
1661 /* orient inverse inertia tensors */
1663 m3x3_mulv( ct
->rba
->iIw
, raCn
, raCnI
);
1664 m3x3_mulv( ct
->rbb
->iIw
, rbCn
, rbCnI
);
1666 ct
->normal_mass
= ct
->rba
->inv_mass
+ ct
->rbb
->inv_mass
;
1667 ct
->normal_mass
+= v3_dot( raCn
, raCnI
);
1668 ct
->normal_mass
+= v3_dot( rbCn
, rbCnI
);
1669 ct
->normal_mass
= 1.0f
/ct
->normal_mass
;
1671 for( int j
=0; j
<2; j
++ ){
1673 v3_cross( ct
->t
[j
], ra
, raCt
);
1674 v3_cross( ct
->t
[j
], rb
, rbCt
);
1675 m3x3_mulv( ct
->rba
->iIw
, raCt
, raCtI
);
1676 m3x3_mulv( ct
->rbb
->iIw
, rbCt
, rbCtI
);
1678 ct
->tangent_mass
[j
] = ct
->rba
->inv_mass
+ ct
->rbb
->inv_mass
;
1679 ct
->tangent_mass
[j
] += v3_dot( raCt
, raCtI
);
1680 ct
->tangent_mass
[j
] += v3_dot( rbCt
, rbCtI
);
1681 ct
->tangent_mass
[j
] = 1.0f
/ct
->tangent_mass
[j
];
1684 rb_debug_contact( ct
);
1689 * Creates relative contact velocity vector
1691 VG_STATIC
void rb_rcv( rigidbody
*rba
, rigidbody
*rbb
, v3f ra
, v3f rb
, v3f rv
)
1694 v3_cross( rba
->w
, ra
, rva
);
1695 v3_add( rba
->v
, rva
, rva
);
1696 v3_cross( rbb
->w
, rb
, rvb
);
1697 v3_add( rbb
->v
, rvb
, rvb
);
1699 v3_sub( rva
, rvb
, rv
);
1702 VG_STATIC
void rb_contact_restitution( rb_ct
*ct
, float cr
)
1705 v3_sub( ct
->co
, ct
->rba
->co
, ra
);
1706 v3_sub( ct
->co
, ct
->rbb
->co
, rb
);
1707 rb_rcv( ct
->rba
, ct
->rbb
, ra
, rb
, rv
);
1709 float v
= v3_dot( rv
, ct
->n
);
1712 ct
->bias
+= -cr
* v
;
1717 * Apply impulse to object
1719 VG_STATIC
void rb_linear_impulse( rigidbody
*rb
, v3f delta
, v3f impulse
)
1722 v3_muladds( rb
->v
, impulse
, rb
->inv_mass
, rb
->v
);
1724 /* Angular velocity */
1726 v3_cross( delta
, impulse
, wa
);
1728 m3x3_mulv( rb
->iIw
, wa
, wa
);
1729 v3_add( rb
->w
, wa
, rb
->w
);
1733 * One iteration to solve the contact constraint
1735 VG_STATIC
void rb_solve_contacts( rb_ct
*buf
, int len
)
1737 for( int i
=0; i
<len
; i
++ ){
1738 struct contact
*ct
= &buf
[i
];
1741 v3_sub( ct
->co
, ct
->rba
->co
, ra
);
1742 v3_sub( ct
->co
, ct
->rbb
->co
, rb
);
1743 rb_rcv( ct
->rba
, ct
->rbb
, ra
, rb
, rv
);
1746 for( int j
=0; j
<2; j
++ ){
1747 float f
= k_friction
* ct
->norm_impulse
,
1748 vt
= v3_dot( rv
, ct
->t
[j
] ),
1749 lambda
= ct
->tangent_mass
[j
] * -vt
;
1751 float temp
= ct
->tangent_impulse
[j
];
1752 ct
->tangent_impulse
[j
] = vg_clampf( temp
+ lambda
, -f
, f
);
1753 lambda
= ct
->tangent_impulse
[j
] - temp
;
1756 v3_muls( ct
->t
[j
], lambda
, impulse
);
1757 rb_linear_impulse( ct
->rba
, ra
, impulse
);
1759 v3_muls( ct
->t
[j
], -lambda
, impulse
);
1760 rb_linear_impulse( ct
->rbb
, rb
, impulse
);
1764 rb_rcv( ct
->rba
, ct
->rbb
, ra
, rb
, rv
);
1765 float vn
= v3_dot( rv
, ct
->n
),
1766 lambda
= ct
->normal_mass
* (-vn
+ ct
->bias
);
1768 float temp
= ct
->norm_impulse
;
1769 ct
->norm_impulse
= vg_maxf( temp
+ lambda
, 0.0f
);
1770 lambda
= ct
->norm_impulse
- temp
;
1773 v3_muls( ct
->n
, lambda
, impulse
);
1774 rb_linear_impulse( ct
->rba
, ra
, impulse
);
1776 v3_muls( ct
->n
, -lambda
, impulse
);
1777 rb_linear_impulse( ct
->rbb
, rb
, impulse
);
1782 * -----------------------------------------------------------------------------
1784 * -----------------------------------------------------------------------------
1787 VG_STATIC
void rb_debug_position_constraints( rb_constr_pos
*buffer
, int len
)
1789 for( int i
=0; i
<len
; i
++ ){
1790 rb_constr_pos
*constr
= &buffer
[i
];
1791 rigidbody
*rba
= constr
->rba
, *rbb
= constr
->rbb
;
1794 m3x3_mulv( rba
->to_world
, constr
->lca
, wca
);
1795 m3x3_mulv( rbb
->to_world
, constr
->lcb
, wcb
);
1798 v3_add( wca
, rba
->co
, p0
);
1799 v3_add( wcb
, rbb
->co
, p1
);
1800 vg_line_pt3( p0
, 0.0025f
, 0xff000000 );
1801 vg_line_pt3( p1
, 0.0025f
, 0xffffffff );
1802 vg_line2( p0
, p1
, 0xff000000, 0xffffffff );
1806 VG_STATIC
void rb_presolve_swingtwist_constraints( rb_constr_swingtwist
*buf
,
1811 for( int i
=0; i
<len
; i
++ ){
1812 rb_constr_swingtwist
*st
= &buf
[ i
];
1814 v3f vx
, vy
, va
, vxb
, axis
, center
;
1816 m3x3_mulv( st
->rba
->to_world
, st
->conevx
, vx
);
1817 m3x3_mulv( st
->rbb
->to_world
, st
->conevxb
, vxb
);
1818 m3x3_mulv( st
->rba
->to_world
, st
->conevy
, vy
);
1819 m3x3_mulv( st
->rbb
->to_world
, st
->coneva
, va
);
1820 m4x3_mulv( st
->rba
->to_world
, st
->view_offset
, center
);
1821 v3_cross( vy
, vx
, axis
);
1823 /* Constraint violated ? */
1824 float fx
= v3_dot( vx
, va
), /* projection world */
1825 fy
= v3_dot( vy
, va
),
1826 fn
= v3_dot( va
, axis
),
1828 rx
= st
->conevx
[3], /* elipse radii */
1831 lx
= fx
/rx
, /* projection local (fn==lz) */
1834 st
->tangent_violation
= ((lx
*lx
+ ly
*ly
) > fn
*fn
) || (fn
<= 0.0f
);
1835 if( st
->tangent_violation
){
1836 /* Calculate a good position and the axis to solve on */
1837 v2f closest
, tangent
,
1838 p
= { fx
/fabsf(fn
), fy
/fabsf(fn
) };
1840 closest_point_elipse( p
, (v2f
){rx
,ry
}, closest
);
1841 tangent
[0] = -closest
[1] / (ry
*ry
);
1842 tangent
[1] = closest
[0] / (rx
*rx
);
1843 v2_normalize( tangent
);
1846 v3_muladds( axis
, vx
, closest
[0], v0
);
1847 v3_muladds( v0
, vy
, closest
[1], v0
);
1850 v3_muls( vx
, tangent
[0], v1
);
1851 v3_muladds( v1
, vy
, tangent
[1], v1
);
1853 v3_copy( v0
, st
->tangent_target
);
1854 v3_copy( v1
, st
->tangent_axis
);
1856 /* calculate mass */
1858 m3x3_mulv( st
->rba
->iIw
, st
->tangent_axis
, aIw
);
1859 m3x3_mulv( st
->rbb
->iIw
, st
->tangent_axis
, bIw
);
1860 st
->tangent_mass
= 1.0f
/ (v3_dot( st
->tangent_axis
, aIw
) +
1861 v3_dot( st
->tangent_axis
, bIw
));
1863 float angle
= v3_dot( va
, st
->tangent_target
);
1867 v3_cross( vy
, va
, refaxis
); /* our default rotation */
1868 v3_normalize( refaxis
);
1870 float angle
= v3_dot( refaxis
, vxb
);
1871 st
->axis_violation
= fabsf(angle
) < st
->conet
;
1873 if( st
->axis_violation
){
1875 v3_cross( refaxis
, vxb
, dir_test
);
1877 if( v3_dot(dir_test
, va
) < 0.0f
)
1878 st
->axis_violation
= -st
->axis_violation
;
1880 float newang
= (float)st
->axis_violation
* acosf(st
->conet
-0.0001f
);
1883 v3_cross( va
, refaxis
, refaxis_up
);
1884 v3_muls( refaxis_up
, sinf(newang
), st
->axis_target
);
1885 v3_muladds( st
->axis_target
, refaxis
, -cosf(newang
), st
->axis_target
);
1887 /* calculate mass */
1888 v3_copy( va
, st
->axis
);
1890 m3x3_mulv( st
->rba
->iIw
, st
->axis
, aIw
);
1891 m3x3_mulv( st
->rbb
->iIw
, st
->axis
, bIw
);
1892 st
->axis_mass
= 1.0f
/ (v3_dot( st
->axis
, aIw
) +
1893 v3_dot( st
->axis
, bIw
));
1898 VG_STATIC
void rb_debug_swingtwist_constraints( rb_constr_swingtwist
*buf
,
1903 for( int i
=0; i
<len
; i
++ ){
1904 rb_constr_swingtwist
*st
= &buf
[ i
];
1906 v3f vx
, vxb
, vy
, va
, axis
, center
;
1908 m3x3_mulv( st
->rba
->to_world
, st
->conevx
, vx
);
1909 m3x3_mulv( st
->rbb
->to_world
, st
->conevxb
, vxb
);
1910 m3x3_mulv( st
->rba
->to_world
, st
->conevy
, vy
);
1911 m3x3_mulv( st
->rbb
->to_world
, st
->coneva
, va
);
1912 m4x3_mulv( st
->rba
->to_world
, st
->view_offset
, center
);
1913 v3_cross( vy
, vx
, axis
);
1915 float rx
= st
->conevx
[3], /* elipse radii */
1919 v3_muladds( center
, va
, size
, p1
);
1920 vg_line( center
, p1
, 0xffffffff );
1921 vg_line_pt3( p1
, 0.00025f
, 0xffffffff );
1923 if( st
->tangent_violation
){
1924 v3_muladds( center
, st
->tangent_target
, size
, p0
);
1926 vg_line( center
, p0
, 0xff00ff00 );
1927 vg_line_pt3( p0
, 0.00025f
, 0xff00ff00 );
1928 vg_line( p1
, p0
, 0xff000000 );
1931 for( int x
=0; x
<32; x
++ ){
1932 float t0
= ((float)x
* (1.0f
/32.0f
)) * VG_TAUf
,
1933 t1
= (((float)x
+1.0f
) * (1.0f
/32.0f
)) * VG_TAUf
,
1940 v3_muladds( axis
, vx
, c0
*rx
, v0
);
1941 v3_muladds( v0
, vy
, s0
*ry
, v0
);
1942 v3_muladds( axis
, vx
, c1
*rx
, v1
);
1943 v3_muladds( v1
, vy
, s1
*ry
, v1
);
1948 v3_muladds( center
, v0
, size
, p0
);
1949 v3_muladds( center
, v1
, size
, p1
);
1951 u32 col0r
= fabsf(c0
) * 255.0f
,
1952 col0g
= fabsf(s0
) * 255.0f
,
1953 col1r
= fabsf(c1
) * 255.0f
,
1954 col1g
= fabsf(s1
) * 255.0f
,
1955 col
= st
->tangent_violation
? 0xff0000ff: 0xff000000,
1956 col0
= col
| (col0r
<<16) | (col0g
<< 8),
1957 col1
= col
| (col1r
<<16) | (col1g
<< 8);
1959 vg_line2( center
, p0
, VG__NONE
, col0
);
1960 vg_line2( p0
, p1
, col0
, col1
);
1964 v3_muladds( center
, va
, size
, p0
);
1965 v3_muladds( p0
, vxb
, size
, p1
);
1967 vg_line( p0
, p1
, 0xff0000ff );
1969 if( st
->axis_violation
){
1970 v3_muladds( p0
, st
->axis_target
, size
*1.25f
, p1
);
1971 vg_line( p0
, p1
, 0xffffff00 );
1972 vg_line_pt3( p1
, 0.0025f
, 0xffffff80 );
1976 v3_cross( vy
, va
, refaxis
); /* our default rotation */
1977 v3_normalize( refaxis
);
1979 v3_cross( va
, refaxis
, refaxis_up
);
1980 float newang
= acosf(st
->conet
-0.0001f
);
1982 v3_muladds( p0
, refaxis_up
, sinf(newang
)*size
, p1
);
1983 v3_muladds( p1
, refaxis
, -cosf(newang
)*size
, p1
);
1984 vg_line( p0
, p1
, 0xff000000 );
1986 v3_muladds( p0
, refaxis_up
, sinf(-newang
)*size
, p1
);
1987 v3_muladds( p1
, refaxis
, -cosf(-newang
)*size
, p1
);
1988 vg_line( p0
, p1
, 0xff404040 );
1993 * Solve a list of positional constraints
1995 VG_STATIC
void rb_solve_position_constraints( rb_constr_pos
*buf
, int len
)
1997 for( int i
=0; i
<len
; i
++ ){
1998 rb_constr_pos
*constr
= &buf
[i
];
1999 rigidbody
*rba
= constr
->rba
, *rbb
= constr
->rbb
;
2002 m3x3_mulv( rba
->to_world
, constr
->lca
, wa
);
2003 m3x3_mulv( rbb
->to_world
, constr
->lcb
, wb
);
2005 m3x3f ssra
, ssrat
, ssrb
, ssrbt
;
2007 m3x3_skew_symetric( ssrat
, wa
);
2008 m3x3_skew_symetric( ssrbt
, wb
);
2009 m3x3_transpose( ssrat
, ssra
);
2010 m3x3_transpose( ssrbt
, ssrb
);
2012 v3f b
, b_wa
, b_wb
, b_a
, b_b
;
2013 m3x3_mulv( ssra
, rba
->w
, b_wa
);
2014 m3x3_mulv( ssrb
, rbb
->w
, b_wb
);
2015 v3_add( rba
->v
, b_wa
, b
);
2016 v3_sub( b
, rbb
->v
, b
);
2017 v3_sub( b
, b_wb
, b
);
2018 v3_muls( b
, -1.0f
, b
);
2021 m3x3_diagonal( invMa
, rba
->inv_mass
);
2022 m3x3_diagonal( invMb
, rbb
->inv_mass
);
2025 m3x3_mul( ssra
, rba
->iIw
, ia
);
2026 m3x3_mul( ia
, ssrat
, ia
);
2027 m3x3_mul( ssrb
, rbb
->iIw
, ib
);
2028 m3x3_mul( ib
, ssrbt
, ib
);
2031 m3x3_add( invMa
, ia
, cma
);
2032 m3x3_add( invMb
, ib
, cmb
);
2035 m3x3_add( cma
, cmb
, A
);
2037 /* Solve Ax = b ( A^-1*b = x ) */
2040 m3x3_inv( A
, invA
);
2041 m3x3_mulv( invA
, b
, impulse
);
2043 v3f delta_va
, delta_wa
, delta_vb
, delta_wb
;
2045 m3x3_mul( rba
->iIw
, ssrat
, iwa
);
2046 m3x3_mul( rbb
->iIw
, ssrbt
, iwb
);
2048 m3x3_mulv( invMa
, impulse
, delta_va
);
2049 m3x3_mulv( invMb
, impulse
, delta_vb
);
2050 m3x3_mulv( iwa
, impulse
, delta_wa
);
2051 m3x3_mulv( iwb
, impulse
, delta_wb
);
2053 v3_add( rba
->v
, delta_va
, rba
->v
);
2054 v3_add( rba
->w
, delta_wa
, rba
->w
);
2055 v3_sub( rbb
->v
, delta_vb
, rbb
->v
);
2056 v3_sub( rbb
->w
, delta_wb
, rbb
->w
);
2060 VG_STATIC
void rb_solve_swingtwist_constraints( rb_constr_swingtwist
*buf
,
2065 for( int i
=0; i
<len
; i
++ ){
2066 rb_constr_swingtwist
*st
= &buf
[ i
];
2068 if( !st
->axis_violation
)
2071 float rv
= v3_dot( st
->axis
, st
->rbb
->w
) -
2072 v3_dot( st
->axis
, st
->rba
->w
);
2074 if( rv
* (float)st
->axis_violation
> 0.0f
)
2077 v3f impulse
, wa
, wb
;
2078 v3_muls( st
->axis
, rv
*st
->axis_mass
, impulse
);
2079 m3x3_mulv( st
->rba
->iIw
, impulse
, wa
);
2080 v3_add( st
->rba
->w
, wa
, st
->rba
->w
);
2082 v3_muls( impulse
, -1.0f
, impulse
);
2083 m3x3_mulv( st
->rbb
->iIw
, impulse
, wb
);
2084 v3_add( st
->rbb
->w
, wb
, st
->rbb
->w
);
2086 float rv2
= v3_dot( st
->axis
, st
->rbb
->w
) -
2087 v3_dot( st
->axis
, st
->rba
->w
);
2090 for( int i
=0; i
<len
; i
++ ){
2091 rb_constr_swingtwist
*st
= &buf
[ i
];
2093 if( !st
->tangent_violation
)
2096 float rv
= v3_dot( st
->tangent_axis
, st
->rbb
->w
) -
2097 v3_dot( st
->tangent_axis
, st
->rba
->w
);
2102 v3f impulse
, wa
, wb
;
2103 v3_muls( st
->tangent_axis
, rv
*st
->tangent_mass
, impulse
);
2104 m3x3_mulv( st
->rba
->iIw
, impulse
, wa
);
2105 v3_add( st
->rba
->w
, wa
, st
->rba
->w
);
2107 v3_muls( impulse
, -1.0f
, impulse
);
2108 m3x3_mulv( st
->rbb
->iIw
, impulse
, wb
);
2109 v3_add( st
->rbb
->w
, wb
, st
->rbb
->w
);
2111 float rv2
= v3_dot( st
->tangent_axis
, st
->rbb
->w
) -
2112 v3_dot( st
->tangent_axis
, st
->rba
->w
);
2116 VG_STATIC
void rb_solve_constr_angle( rigidbody
*rba
, rigidbody
*rbb
,
2119 m3x3f ssra
, ssrb
, ssrat
, ssrbt
;
2122 m3x3_skew_symetric( ssrat
, ra
);
2123 m3x3_skew_symetric( ssrbt
, rb
);
2124 m3x3_transpose( ssrat
, ssra
);
2125 m3x3_transpose( ssrbt
, ssrb
);
2127 m3x3_mul( ssra
, rba
->iIw
, cma
);
2128 m3x3_mul( cma
, ssrat
, cma
);
2129 m3x3_mul( ssrb
, rbb
->iIw
, cmb
);
2130 m3x3_mul( cmb
, ssrbt
, cmb
);
2133 m3x3_add( cma
, cmb
, A
);
2134 m3x3_inv( A
, invA
);
2137 m3x3_mulv( ssra
, rba
->w
, b_wa
);
2138 m3x3_mulv( ssrb
, rbb
->w
, b_wb
);
2139 v3_add( b_wa
, b_wb
, b
);
2143 m3x3_mulv( invA
, b
, impulse
);
2145 v3f delta_wa
, delta_wb
;
2147 m3x3_mul( rba
->iIw
, ssrat
, iwa
);
2148 m3x3_mul( rbb
->iIw
, ssrbt
, iwb
);
2149 m3x3_mulv( iwa
, impulse
, delta_wa
);
2150 m3x3_mulv( iwb
, impulse
, delta_wb
);
2151 v3_add( rba
->w
, delta_wa
, rba
->w
);
2152 v3_sub( rbb
->w
, delta_wb
, rbb
->w
);
2156 * Correct position constraint drift errors
2157 * [ 0.0 <= amt <= 1.0 ]: the correction amount
2159 VG_STATIC
void rb_correct_position_constraints( rb_constr_pos
*buf
, int len
,
2162 for( int i
=0; i
<len
; i
++ ){
2163 rb_constr_pos
*constr
= &buf
[i
];
2164 rigidbody
*rba
= constr
->rba
, *rbb
= constr
->rbb
;
2167 m3x3_mulv( rba
->to_world
, constr
->lca
, p0
);
2168 m3x3_mulv( rbb
->to_world
, constr
->lcb
, p1
);
2169 v3_add( rba
->co
, p0
, p0
);
2170 v3_add( rbb
->co
, p1
, p1
);
2171 v3_sub( p1
, p0
, d
);
2173 v3_muladds( rbb
->co
, d
, -1.0f
* amt
, rbb
->co
);
2174 rb_update_transform( rbb
);
2178 VG_STATIC
void rb_correct_swingtwist_constraints( rb_constr_swingtwist
*buf
,
2179 int len
, float amt
)
2181 for( int i
=0; i
<len
; i
++ ){
2182 rb_constr_swingtwist
*st
= &buf
[i
];
2184 if( !st
->tangent_violation
)
2188 m3x3_mulv( st
->rbb
->to_world
, st
->coneva
, va
);
2190 float angle
= v3_dot( va
, st
->tangent_target
);
2192 if( fabsf(angle
) < 0.9999f
){
2194 v3_cross( va
, st
->tangent_target
, axis
);
2197 q_axis_angle( correction
, axis
, acosf(angle
) * amt
);
2198 q_mul( correction
, st
->rbb
->q
, st
->rbb
->q
);
2199 rb_update_transform( st
->rbb
);
2203 for( int i
=0; i
<len
; i
++ ){
2204 rb_constr_swingtwist
*st
= &buf
[i
];
2206 if( !st
->axis_violation
)
2210 m3x3_mulv( st
->rbb
->to_world
, st
->conevxb
, vxb
);
2212 float angle
= v3_dot( vxb
, st
->axis_target
);
2214 if( fabsf(angle
) < 0.9999f
){
2216 v3_cross( vxb
, st
->axis_target
, axis
);
2219 q_axis_angle( correction
, axis
, acosf(angle
) * amt
);
2220 q_mul( correction
, st
->rbb
->q
, st
->rbb
->q
);
2221 rb_update_transform( st
->rbb
);
2226 VG_STATIC
void rb_correct_contact_constraints( rb_ct
*buf
, int len
, float amt
)
2228 for( int i
=0; i
<len
; i
++ ){
2229 rb_ct
*ct
= &buf
[i
];
2230 rigidbody
*rba
= ct
->rba
,
2233 float mass_total
= 1.0f
/ (rba
->inv_mass
+ rbb
->inv_mass
);
2235 v3_muladds( rba
->co
, ct
->n
, -mass_total
* rba
->inv_mass
, rba
->co
);
2236 v3_muladds( rbb
->co
, ct
->n
, mass_total
* rbb
->inv_mass
, rbb
->co
);
2245 VG_STATIC
void rb_effect_simple_bouyency( rigidbody
*ra
, v4f plane
,
2246 float amt
, float drag
)
2249 float depth
= v3_dot( plane
, ra
->co
) - plane
[3],
2250 lambda
= vg_clampf( -depth
, 0.0f
, 1.0f
) * amt
;
2252 v3_muladds( ra
->v
, plane
, lambda
* k_rb_delta
, ra
->v
);
2255 v3_muls( ra
->v
, 1.0f
-(drag
*k_rb_delta
), ra
->v
);
2258 /* apply a spring&dampener force to match ra(worldspace) on rigidbody, to
2261 VG_STATIC
void rb_effect_spring_target_vector( rigidbody
*rba
, v3f ra
, v3f rt
,
2262 float spring
, float dampening
,
2265 float d
= v3_dot( rt
, ra
);
2266 float a
= vg_signf( d
) * acosf( vg_clampf( d
, -1.0f
, 1.0f
) );
2269 v3_cross( rt
, ra
, axis
);
2271 float Fs
= -a
* spring
,
2272 Fd
= -v3_dot( rba
->w
, axis
) * dampening
;
2274 v3_muladds( rba
->w
, axis
, (Fs
+Fd
) * timestep
, rba
->w
);
2277 #endif /* RIGIDBODY_H */