X-Git-Url: https://harrygodden.com/git/?a=blobdiff_plain;f=rigidbody.h;h=c00b0f04f75817ad21072755ed983ce098094bfb;hb=84a7ae83a25966e0004a1a4b409dbb3d49fae286;hp=eeed74500a8db526484d788bd935d2bcf276fc6d;hpb=6d66c67945f84476d6ac75a0497007cc30bcf58c;p=carveJwlIkooP6JGAAIwe30JlM.git diff --git a/rigidbody.h b/rigidbody.h index eeed745..c00b0f0 100644 --- a/rigidbody.h +++ b/rigidbody.h @@ -17,36 +17,70 @@ static bh_system bh_system_rigidbodies; #define k_rb_delta (1.0f/k_rb_rate) typedef struct rigidbody rigidbody; +typedef struct contact rb_ct; + struct rigidbody { - v3f co, v, I; + v3f co, v, w; v4f q; enum rb_shape { k_rb_shape_box, + k_rb_shape_sphere, k_rb_shape_capsule } type; - v3f top, bottom; - float radius; + + union + { + struct rb_sphere + { + float radius; + } + sphere; + + struct rb_capsule + { + float height, radius; + } + capsule; + } + inf; + + v3f right, up, forward; + + int is_world; boxf bbx, bbx_world; float inv_mass; - struct contact - { - v3f co, n, delta; - v3f t[2]; - float bias, norm_impulse, tangent_impulse[2]; - } - manifold[12]; - int manifold_count; - v3f delta; /* where is the origin of this in relation to a parent body */ m4x3f to_world, to_local; }; +static rigidbody rb_static_null = +{ + .co={0.0f,0.0f,0.0f}, + .q={0.0f,0.0f,0.0f,1.0f}, + .v={0.0f,0.0f,0.0f}, + .w={0.0f,0.0f,0.0f}, + .is_world = 1, + .inv_mass = 0.0f +}; + +static void rb_debug( rigidbody *rb, u32 colour ); + +static struct contact +{ + rigidbody *rba, *rbb; + v3f co, n; + v3f t[2]; + float mass_total, p, bias, norm_impulse, tangent_impulse[2]; +} +rb_contact_buffer[256]; +static int rb_contact_count = 0; + static void rb_update_transform( rigidbody *rb ) { q_normalize( rb->q ); @@ -57,18 +91,57 @@ static void rb_update_transform( rigidbody *rb ) box_copy( rb->bbx, rb->bbx_world ); m4x3_transform_aabb( rb->to_world, rb->bbx_world ); + + m3x3_mulv( rb->to_world, (v3f){1.0f,0.0f, 0.0f}, rb->right ); + m3x3_mulv( rb->to_world, (v3f){0.0f,1.0f, 0.0f}, rb->up ); + m3x3_mulv( rb->to_world, (v3f){0.0f,0.0f,-1.0f}, rb->forward ); +} + +static float sphere_volume( float radius ) +{ + float r3 = radius*radius*radius; + return (4.0f/3.0f) * VG_PIf * r3; } static void rb_init( rigidbody *rb ) { - q_identity( rb->q ); - v3_zero( rb->v ); - v3_zero( rb->I ); + float volume = 1.0f; + + if( rb->type == k_rb_shape_box ) + { + v3f dims; + v3_sub( rb->bbx[1], rb->bbx[0], dims ); + volume = dims[0]*dims[1]*dims[2]; + } + else if( rb->type == k_rb_shape_sphere ) + { + volume = sphere_volume( rb->inf.sphere.radius ); + v3_fill( rb->bbx[0], -rb->inf.sphere.radius ); + v3_fill( rb->bbx[1], rb->inf.sphere.radius ); + } + else if( rb->type == k_rb_shape_capsule ) + { + float r = rb->inf.capsule.radius, + h = rb->inf.capsule.height; + volume = sphere_volume( r ) + VG_PIf * r*r * (h - r*2.0f); + + v3_fill( rb->bbx[0], -rb->inf.sphere.radius ); + v3_fill( rb->bbx[1], rb->inf.sphere.radius ); + rb->bbx[0][1] = -h; + rb->bbx[1][1] = h; + } - v3f dims; - v3_sub( rb->bbx[1], rb->bbx[0], dims ); + if( rb->is_world ) + { + rb->inv_mass = 0.0f; + } + else + { + rb->inv_mass = 1.0f/(8.0f*volume); + } - rb->inv_mass = 1.0f/(8.0f*dims[0]*dims[1]*dims[2]); + v3_zero( rb->v ); + v3_zero( rb->w ); rb_update_transform( rb ); } @@ -80,14 +153,14 @@ static void rb_iter( rigidbody *rb ) /* intergrate velocity */ v3_muladds( rb->co, rb->v, k_rb_delta, rb->co ); - v3_lerp( rb->I, (v3f){0.0f,0.0f,0.0f}, 0.0025f, rb->I ); + v3_lerp( rb->w, (v3f){0.0f,0.0f,0.0f}, 0.0025f, rb->w ); /* inegrate inertia */ - if( v3_length2( rb->I ) > 0.0f ) + if( v3_length2( rb->w ) > 0.0f ) { v4f rotation; v3f axis; - v3_copy( rb->I, axis ); + v3_copy( rb->w, axis ); float mag = v3_length( axis ); v3_divs( axis, mag, axis ); @@ -98,7 +171,7 @@ static void rb_iter( rigidbody *rb ) static void rb_torque( rigidbody *rb, v3f axis, float mag ) { - v3_muladds( rb->I, axis, mag*k_rb_delta, rb->I ); + v3_muladds( rb->w, axis, mag*k_rb_delta, rb->w ); } static void rb_tangent_basis( v3f n, v3f tx, v3f ty ) @@ -121,13 +194,454 @@ static void rb_tangent_basis( v3f n, v3f tx, v3f ty ) v3_cross( n, tx, ty ); } +static void rb_solver_reset(void); +static void rb_build_manifold_terrain( rigidbody *rb ); +static void rb_build_manifold_terrain_sphere( rigidbody *rb ); +static void rb_solve_contacts(void); + +/* + * These closest point tests were learned from Real-Time Collision Detection by + * Christer Ericson + */ +static float closest_segment_segment( v3f p1, v3f q1, v3f p2, v3f q2, + float *s, float *t, v3f c1, v3f c2) +{ + v3f d1,d2,r; + v3_sub( q1, p1, d1 ); + v3_sub( q2, p2, d2 ); + v3_sub( p1, p2, r ); + + float a = v3_length2( d1 ), + e = v3_length2( d2 ), + f = v3_dot( d2, r ); + + const float kEpsilon = 0.0001f; + + if( a <= kEpsilon && e <= kEpsilon ) + { + *s = 0.0f; + *t = 0.0f; + v3_copy( p1, c1 ); + v3_copy( p2, c2 ); + + v3f v0; + v3_sub( c1, c2, v0 ); + + return v3_length2( v0 ); + } + + if( a<= kEpsilon ) + { + *s = 0.0f; + *t = vg_clampf( f / e, 0.0f, 1.0f ); + } + else + { + float c = v3_dot( d1, r ); + if( e <= kEpsilon ) + { + *t = 0.0f; + *s = vg_clampf( -c / a, 0.0f, 1.0f ); + } + else + { + float b = v3_dot(d1,d2), + d = a*e-b*b; + + if( d != 0.0f ) + { + *s = vg_clampf((b*f - c*e)/d, 0.0f, 1.0f); + } + else + { + *s = 0.0f; + } + + *t = (b*(*s)+f) / e; + + if( *t < 0.0f ) + { + *t = 0.0f; + *s = vg_clampf( -c / a, 0.0f, 1.0f ); + } + else if( *t > 1.0f ) + { + *t = 1.0f; + *s = vg_clampf((b-c)/a,0.0f,1.0f); + } + } + } + + v3_muladds( p1, d1, *s, c1 ); + v3_muladds( p2, d2, *t, c2 ); + + v3f v0; + v3_sub( c1, c2, v0 ); + return v3_length2( v0 ); +} + +static void closest_point_aabb( v3f p, boxf box, v3f dest ) +{ + v3_maxv( p, box[0], dest ); + v3_minv( dest, box[1], dest ); +} + +static void closest_point_obb( v3f p, rigidbody *rb, v3f dest ) +{ + v3f local; + m4x3_mulv( rb->to_local, p, local ); + closest_point_aabb( local, rb->bbx, local ); + m4x3_mulv( rb->to_world, local, dest ); +} + +static void closest_point_segment( v3f a, v3f b, v3f point, v3f dest ) +{ + v3f v0, v1; + v3_sub( b, a, v0 ); + v3_sub( point, a, v1 ); + + float t = v3_dot( v1, v0 ) / v3_length2(v0); + v3_muladds( a, v0, vg_clampf(t,0.0f,1.0f), dest ); +} + +static void closest_on_triangle( v3f p, v3f tri[3], v3f dest ) +{ + v3f ab, ac, ap; + float d1, d2; + + /* Region outside A */ + v3_sub( tri[1], tri[0], ab ); + v3_sub( tri[2], tri[0], ac ); + v3_sub( p, tri[0], ap ); + + d1 = v3_dot(ab,ap); + d2 = v3_dot(ac,ap); + if( d1 <= 0.0f && d2 <= 0.0f ) + { + v3_copy( tri[0], dest ); + v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); + return; + } + + /* Region outside B */ + v3f bp; + float d3, d4; + + v3_sub( p, tri[1], bp ); + d3 = v3_dot( ab, bp ); + d4 = v3_dot( ac, bp ); + + if( d3 >= 0.0f && d4 <= d3 ) + { + v3_copy( tri[1], dest ); + v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); + return; + } + + /* Edge region of AB */ + float vc = d1*d4 - d3*d2; + if( vc <= 0.0f && d1 >= 0.0f && d3 <= 0.0f ) + { + float v = d1 / (d1-d3); + v3_muladds( tri[0], ab, v, dest ); + v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); + return; + } + + /* Region outside C */ + v3f cp; + float d5, d6; + v3_sub( p, tri[2], cp ); + d5 = v3_dot(ab, cp); + d6 = v3_dot(ac, cp); + + if( d6 >= 0.0f && d5 <= d6 ) + { + v3_copy( tri[2], dest ); + v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); + return; + } + + /* Region of AC */ + float vb = d5*d2 - d1*d6; + if( vb <= 0.0f && d2 >= 0.0f && d6 <= 0.0f ) + { + float w = d2 / (d2-d6); + v3_muladds( tri[0], ac, w, dest ); + v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); + return; + } + + /* Region of BC */ + float va = d3*d6 - d5*d4; + if( va <= 0.0f && (d4-d3) >= 0.0f && (d5-d6) >= 0.0f ) + { + float w = (d4-d3) / ((d4-d3) + (d5-d6)); + v3f bc; + v3_sub( tri[2], tri[1], bc ); + v3_muladds( tri[1], bc, w, dest ); + v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); + return; + } + + /* P inside region, Q via barycentric coordinates uvw */ + float d = 1.0f/(va+vb+vc), + v = vb*d, + w = vc*d; + + v3_muladds( tri[0], ab, v, dest ); + v3_muladds( dest, ac, w, dest ); +} + +/* + * Contact generators + * + * These do not automatically allocate contacts, an appropriately sized + * buffer must be supplied. The function returns the size of the manifold + * which was generated. + * + * The values set on the contacts are: n, co, p, rba, rbb + */ + +static void rb_debug_contact( rb_ct *ct ) +{ + v3f p1; + v3_muladds( ct->co, ct->n, 0.2f, p1 ); + vg_line_pt3( ct->co, 0.1f, 0xff0000ff ); + vg_line( ct->co, p1, 0xffffffff ); +} + +static int rb_sphere_vs_box( rigidbody *rba, rigidbody *rbb, rb_ct *buf ) +{ + v3f co, delta; + + closest_point_obb( rba->co, rbb, co ); + v3_sub( rba->co, co, delta ); + + float d2 = v3_length2(delta), + r = rba->inf.sphere.radius; + + if( d2 <= r*r ) + { + float d; + if( d2 <= 0.0001f ) + { + v3_sub( rbb->co, rba->co, delta ); + d2 = v3_length2(delta); + } + + d = sqrtf(d2); + + rb_ct *ct = buf; + v3_muls( delta, 1.0f/d, ct->n ); + v3_copy( co, ct->co ); + ct->p = r-d; + ct->rba = rba; + ct->rbb = rbb; + return 1; + } + + return 0; +} + +static int rb_sphere_vs_sphere( rigidbody *rba, rigidbody *rbb, rb_ct *buf ) +{ + v3f delta; + v3_sub( rba->co, rbb->co, delta ); + + float d2 = v3_length2(delta), + r = rba->inf.sphere.radius + rbb->inf.sphere.radius; + + if( d2 < r*r ) + { + float d = sqrtf(d2); + + rb_ct *ct = buf; + v3_muls( delta, -1.0f/d, ct->n ); + + v3f p0, p1; + v3_muladds( rba->co, ct->n, rba->inf.sphere.radius, p0 ); + v3_muladds( rbb->co, ct->n,-rbb->inf.sphere.radius, p1 ); + v3_add( p0, p1, ct->co ); + v3_muls( ct->co, 0.5f, ct->co ); + ct->p = r-d; + ct->rba = rba; + ct->rbb = rbb; + return 1; + } + + return 0; +} + +static int rb_box_vs_sphere( rigidbody *rba, rigidbody *rbb, rb_ct *buf ) +{ + return rb_sphere_vs_box( rbb, rba, buf ); +} + +static int rb_box_vs_box( rigidbody *rba, rigidbody *rbb, rb_ct *buf ) +{ + /* TODO: Generating a stable quad manifold, lots of clipping */ + return 0; +} + +/* + * This function does not accept triangle as a dynamic object, it is assumed + * to always be static. + * + * The triangle is also assumed to be one sided for better detection + */ +static int rb_sphere_vs_triangle( rigidbody *rba, v3f tri[3], rb_ct *buf ) +{ + v3f delta, co; + + closest_on_triangle( rba->co, tri, co ); + v3_sub( rba->co, co, delta ); + + float d2 = v3_length2( delta ), + r = rba->inf.sphere.radius; + + if( d2 < r*r ) + { + v3f ab, ac, tn; + v3_sub( tri[1], tri[0], ab ); + v3_sub( tri[2], tri[0], ac ); + v3_cross( ac, ab, tn ); + + if( v3_dot( delta, tn ) > 0.0f ) + v3_muls( delta, -1.0f, delta ); + + float d = sqrtf(d2); + + rb_ct *ct = buf; + v3_muls( delta, 1.0f/d, ct->n ); + v3_copy( co, ct->co ); + ct->p = r-d; + ct->rba = rba; + ct->rbb = &rb_static_null; + return 1; + } + + return 0; +} + + +/* + * Generic functions + */ + +RB_DEPR +static int sphere_vs_triangle( v3f c, float r, v3f tri[3], + v3f co, v3f norm, float *p ) +{ + v3f delta; + closest_on_triangle( c, tri, co ); + + v3_sub( c, co, delta ); + + + float d = v3_length2( delta ); + if( d < r*r ) + { + v3f ab, ac, tn; + v3_sub( tri[1], tri[0], ab ); + v3_sub( tri[2], tri[0], ac ); + v3_cross( ac, ab, tn ); + + if( v3_dot( delta, tn ) > 0.0f ) + v3_muls( delta, -1.0f, delta ); + + vg_line_pt3( co, 0.05f, 0xff00ff00 ); + + d = sqrtf(d); + v3_muls( delta, 1.0f/d, norm ); + + *p = r-d; + return 1; + } + + return 0; +} + #include "world.h" -static void rb_manifold_reset( rigidbody *rb ) +static void rb_solver_reset(void) +{ + rb_contact_count = 0; +} + +static rb_ct *rb_global_ct(void) +{ + return rb_contact_buffer + rb_contact_count; +} + +static struct contact *rb_start_contact(void) +{ + if( rb_contact_count == vg_list_size(rb_contact_buffer) ) + { + vg_error( "rigidbody: too many contacts generated (%u)\n", + rb_contact_count ); + return NULL; + } + + return &rb_contact_buffer[ rb_contact_count ]; +} + +static void rb_commit_contact( struct contact *ct, float p ) +{ + ct->bias = -0.2f*k_rb_rate*vg_minf(0.0f,-p+0.04f); + rb_tangent_basis( ct->n, ct->t[0], ct->t[1] ); + + ct->norm_impulse = 0.0f; + ct->tangent_impulse[0] = 0.0f; + ct->tangent_impulse[1] = 0.0f; + + rb_contact_count ++; +} + +static void rb_build_manifold_terrain_sphere( rigidbody *rb ) { - rb->manifold_count = 0; + u32 geo[256]; + v3f tri[3]; + int len = bh_select( &world.geo.bhtris, rb->bbx_world, geo, 256 ); + + for( int i=0; ico, rb->inf.sphere.radius, tri,co,norm,&p)) + { + struct contact *ct = rb_start_contact(); + + if( !ct ) + return; + + v3f p1; + v3_muladds( rb->co, norm, p, p1 ); + vg_line( rb->co, p1, 0xffffffff ); + + ct->rba = rb; + v3_copy( co, ct->co ); + v3_copy( norm, ct->n ); + rb_commit_contact( ct, p ); + } + } + } + } +RB_DEPR static void rb_build_manifold_terrain( rigidbody *rb ) { v3f *box = rb->bbx; @@ -159,7 +673,12 @@ static void rb_build_manifold_terrain( rigidbody *rb ) for( int i=0; i<8; i++ ) { float *point = pts[i]; - struct contact *ct = &rb->manifold[rb->manifold_count]; + struct contact *ct = rb_start_contact(); + + if( !ct ) + return; + + ct->rba = rb; v3f surface; v3_copy( point, surface ); @@ -170,77 +689,123 @@ static void rb_build_manifold_terrain( rigidbody *rb ) if( !ray_world( surface, (v3f){0.0f,-1.0f,0.0f}, &hit )) continue; - v3_copy( hit.normal, ct->n ); - v3_copy( hit.pos, surface ); + v3_copy( hit.pos, surface ); + + float p = vg_minf( surface[1] - point[1], 1.0f ); + + if( p > 0.0f ) + { + v3_copy( hit.normal, ct->n ); + v3_add( point, surface, ct->co ); + v3_muls( ct->co, 0.5f, ct->co ); + + rb_commit_contact( ct, p ); + count ++; + if( count == 4 ) + break; + } + } +} + +/* + * Initializing things like tangent vectors + */ +static void rb_presolve_contacts(void) +{ + for( int i=0; ibias = -0.2f * k_rb_rate * vg_minf(0.0f,-ct->p+0.04f); + rb_tangent_basis( ct->n, ct->t[0], ct->t[1] ); - float p = vg_minf( surface[1] - point[1], 1.0f ); + ct->norm_impulse = 0.0f; + ct->tangent_impulse[0] = 0.0f; + ct->tangent_impulse[1] = 0.0f; + ct->mass_total = 1.0f/(ct->rba->inv_mass + ct->rbb->inv_mass); - if( p > 0.0f ) - { - v3_add( point, surface, ct->co ); - v3_muls( ct->co, 0.5f, ct->co ); + rb_debug_contact( ct ); + } +} - //vg_line_pt3( ct->co, 0.0125f, 0xff0000ff ); +/* + * Creates relative contact velocity vector, and offsets between each body */ +static void rb_rcv( rb_ct *ct, v3f rv, v3f da, v3f db ) +{ + rigidbody *rba = ct->rba, + *rbb = ct->rbb; - v3_sub( ct->co, rb->co, ct->delta ); - ct->bias = -0.2f * (1.0f/k_rb_delta) * vg_minf( 0.0f, -p+0.04f ); - rb_tangent_basis( ct->n, ct->t[0], ct->t[1] ); + v3_sub( rba->co, ct->co, da ); + v3_sub( rbb->co, ct->co, db ); + + v3f rva, rvb; + v3_cross( rba->w, da, rva ); + v3_add( rba->v, rva, rva ); - ct->norm_impulse = 0.0f; - ct->tangent_impulse[0] = 0.0f; - ct->tangent_impulse[1] = 0.0f; + v3_cross( rbb->w, db, rvb ); + v3_add( rbb->v, rvb, rvb ); + v3_add( rva, rvb, rv ); +} - rb->manifold_count ++; - count ++; - if( count == 4 ) - break; - } - } +static void rb_standard_impulse( rb_ct *ct, v3f da, v3f db, v3f impulse ) +{ + rigidbody *rba = ct->rba, + *rbb = ct->rbb; + + /* response */ + v3_muladds( rba->v, impulse, ct->mass_total * rba->inv_mass, rba->v ); + v3_muladds( rbb->v, impulse, ct->mass_total * rbb->inv_mass, rbb->v ); + + /* Angular velocity */ + v3f wa, wb; + v3_cross( da, impulse, wa ); + v3_cross( db, impulse, wb ); + v3_muladds( rba->w, wa, ct->mass_total * rba->inv_mass, rba->w ); + v3_muladds( rbb->w, wb, ct->mass_total * rbb->inv_mass, rbb->w ); } -static void rb_constraint_manifold( rigidbody *rb ) +static void rb_solve_contacts(void) { float k_friction = 0.1f; + /* TODO: second object + * Static objects route to static element */ + /* Friction Impulse */ - for( int i=0; imanifold_count; i++ ) + for( int i=0; imanifold[i]; + struct contact *ct = &rb_contact_buffer[i]; + rigidbody *rb = ct->rba; - v3f dv; - v3_cross( rb->I, ct->delta, dv ); - v3_add( rb->v, dv, dv ); + v3f rv, da, db; + rb_rcv( ct, rv, da, db ); for( int j=0; j<2; j++ ) { - float vt = vg_clampf( -v3_dot( dv, ct->t[j] ), - -k_friction, k_friction ); - - vt = -v3_dot( dv, ct->t[j] ); + float f = k_friction * ct->norm_impulse, + vt = -v3_dot( rv, ct->t[j] ); float temp = ct->tangent_impulse[j]; - ct->tangent_impulse[j] = vg_clampf( temp+vt, -k_friction, k_friction ); + ct->tangent_impulse[j] = vg_clampf( temp+vt, -f, f ); vt = ct->tangent_impulse[j] - temp; v3f impulse; - v3_muls( ct->t[j], vt, impulse ); - v3_add( impulse, rb->v, rb->v ); - v3_cross( ct->delta, impulse, impulse ); - v3_add( impulse, rb->I, rb->I ); + rb_standard_impulse( ct, da, db, impulse ); } } /* Normal Impulse */ - for( int i=0; imanifold_count; i++ ) + for( int i=0; imanifold[i]; + struct contact *ct = &rb_contact_buffer[i]; + rigidbody *rba = ct->rba, + *rbb = ct->rbb; - v3f dv; - v3_cross( rb->I, ct->delta, dv ); - v3_add( rb->v, dv, dv ); + v3f rv, da, db; + rb_rcv( ct, rv, da, db ); - float vn = -v3_dot( dv, ct->n ); + float vn = -v3_dot( rv, ct->n ); vn += ct->bias; float temp = ct->norm_impulse; @@ -248,11 +813,8 @@ static void rb_constraint_manifold( rigidbody *rb ) vn = ct->norm_impulse - temp; v3f impulse; - v3_muls( ct->n, vn, impulse ); - v3_add( impulse, rb->v, rb->v ); - v3_cross( ct->delta, impulse, impulse ); - v3_add( impulse, rb->I, rb->I ); + rb_standard_impulse( ct, da, db, impulse ); } } @@ -313,8 +875,8 @@ static void rb_constraint_angle( rigidbody *rba, v3f va, v3f axis; v3_cross( wva, wvb, axis ); - v3_muladds( rba->I, axis, ang*spring*0.5f, rba->I ); - v3_muladds( rbb->I, axis, -ang*spring*0.5f, rbb->I ); + v3_muladds( rba->w, axis, ang*spring*0.5f, rba->w ); + v3_muladds( rbb->w, axis, -ang*spring*0.5f, rbb->w ); return; @@ -344,8 +906,8 @@ static void rb_relative_velocity( rigidbody *ra, v3f lca, v3_sub( ra->v, rb->v, rcv ); v3f rcv_Ra, rcv_Rb; - v3_cross( ra->I, wca, rcv_Ra ); - v3_cross( rb->I, wcb, rcv_Rb ); + v3_cross( ra->w, wca, rcv_Ra ); + v3_cross( rb->w, wcb, rcv_Rb ); v3_add( rcv_Ra, rcv, rcv ); v3_sub( rcv, rcv_Rb, rcv ); } @@ -370,8 +932,8 @@ static void rb_constraint_position( rigidbody *ra, v3f lca, v3_sub( ra->v, rb->v, rcv ); v3f rcv_Ra, rcv_Rb; - v3_cross( ra->I, wca, rcv_Ra ); - v3_cross( rb->I, wcb, rcv_Rb ); + v3_cross( ra->w, wca, rcv_Ra ); + v3_cross( rb->w, wcb, rcv_Rb ); v3_add( rcv_Ra, rcv, rcv ); v3_sub( rcv, rcv_Rb, rcv ); @@ -385,12 +947,12 @@ static void rb_constraint_position( rigidbody *ra, v3f lca, v3_muls( rcv, 1.0f, impulse ); v3_muladds( rb->v, impulse, mass_b/total_mass, rb->v ); v3_cross( wcb, impulse, impulse ); - v3_add( impulse, rb->I, rb->I ); + v3_add( impulse, rb->w, rb->w ); v3_muls( rcv, -1.0f, impulse ); v3_muladds( ra->v, impulse, mass_a/total_mass, ra->v ); v3_cross( wca, impulse, impulse ); - v3_add( impulse, ra->I, ra->I ); + v3_add( impulse, ra->w, ra->w ); #if 0 /* @@ -402,20 +964,61 @@ static void rb_constraint_position( rigidbody *ra, v3f lca, v3_add( impulse, ra->v, ra->v ); v3_cross( wca, impulse, impulse ); - v3_add( impulse, ra->I, ra->I ); + v3_add( impulse, ra->w, ra->w ); v3_muls( delta, -0.5f*spring, impulse ); v3_add( impulse, rb->v, rb->v ); v3_cross( wcb, impulse, impulse ); - v3_add( impulse, rb->I, rb->I ); + v3_add( impulse, rb->w, rb->w ); #endif } +static void debug_sphere( m4x3f m, float radius, u32 colour ) +{ + v3f ly = { 0.0f, 0.0f, radius }, + lx = { 0.0f, radius, 0.0f }, + lz = { 0.0f, 0.0f, radius }; + + for( int i=0; i<16; i++ ) + { + float t = ((float)(i+1) * (1.0f/16.0f)) * VG_PIf * 2.0f, + s = sinf(t), + c = cosf(t); + + v3f py = { s*radius, 0.0f, c*radius }, + px = { s*radius, c*radius, 0.0f }, + pz = { 0.0f, s*radius, c*radius }; + + v3f p0, p1, p2, p3, p4, p5; + m4x3_mulv( m, py, p0 ); + m4x3_mulv( m, ly, p1 ); + m4x3_mulv( m, px, p2 ); + m4x3_mulv( m, lx, p3 ); + m4x3_mulv( m, pz, p4 ); + m4x3_mulv( m, lz, p5 ); + + vg_line( p0, p1, colour == 0x00? 0xff00ff00: colour ); + vg_line( p2, p3, colour == 0x00? 0xff0000ff: colour ); + vg_line( p4, p5, colour == 0x00? 0xffff0000: colour ); + + v3_copy( py, ly ); + v3_copy( px, lx ); + v3_copy( pz, lz ); + } +} + static void rb_debug( rigidbody *rb, u32 colour ) { - v3f *box = rb->bbx; - vg_line_boxf_transformed( rb->to_world, rb->bbx, colour ); + if( rb->type == k_rb_shape_box ) + { + v3f *box = rb->bbx; + vg_line_boxf_transformed( rb->to_world, rb->bbx, colour ); + } + else if( rb->type == k_rb_shape_sphere ) + { + debug_sphere( rb->to_world, rb->inf.sphere.radius, colour ); + } } /* @@ -467,6 +1070,7 @@ static int rb_point_in_body( rigidbody *rb, v3f pos, float *pen, v3f normal ) return 0; } +#if 0 static void rb_build_manifold_rb_static( rigidbody *ra, rigidbody *rb_static ) { v3f verts[8]; @@ -520,220 +1124,12 @@ static void rb_build_manifold_rb_static( rigidbody *ra, rigidbody *rb_static ) } } } +#endif /* * Capsule phyics */ -static float closest_segment_segment( v3f p1, v3f q1, v3f p2, v3f q2, - float *s, float *t, v3f c1, v3f c2) -{ - v3f d1,d2,r; - v3_sub( q1, p1, d1 ); - v3_sub( q2, p2, d2 ); - v3_sub( p1, p2, r ); - - float a = v3_length2( d1 ), - e = v3_length2( d2 ), - f = v3_dot( d2, r ); - - const float kEpsilon = 0.0001f; - - if( a <= kEpsilon && e <= kEpsilon ) - { - *s = 0.0f; - *t = 0.0f; - v3_copy( p1, c1 ); - v3_copy( p2, c2 ); - - v3f v0; - v3_sub( c1, c2, v0 ); - - return v3_length2( v0 ); - } - - if( a<= kEpsilon ) - { - *s = 0.0f; - *t = vg_clampf( f / e, 0.0f, 1.0f ); - } - else - { - float c = v3_dot( d1, r ); - if( e <= kEpsilon ) - { - *t = 0.0f; - *s = vg_clampf( -c / a, 0.0f, 1.0f ); - } - else - { - float b = v3_dot(d1,d2), - d = a*e-b*b; - - if( d != 0.0f ) - { - *s = vg_clampf((b*f - c*e)/d, 0.0f, 1.0f); - } - else - { - *s = 0.0f; - } - - *t = (b*(*s)+f) / e; - - if( *t < 0.0f ) - { - *t = 0.0f; - *s = vg_clampf( -c / a, 0.0f, 1.0f ); - } - else if( *t > 1.0f ) - { - *t = 1.0f; - *s = vg_clampf((b-c)/a,0.0f,1.0f); - } - } - } - - v3_muladds( p1, d1, *s, c1 ); - v3_muladds( p2, d2, *t, c2 ); - - v3f v0; - v3_sub( c1, c2, v0 ); - return v3_length2( v0 ); -} - -static void closest_point_segment( v3f a, v3f b, v3f point, v3f dest ) -{ - v3f v0, v1; - v3_sub( b, a, v0 ); - v3_sub( point, a, v1 ); - - float t = v3_dot( v1, v0 ) / v3_length2(v0); - v3_muladds( a, v0, vg_clampf(t,0.0f,1.0f), dest ); -} - -/* Real-Time Collision Detection */ -static void closest_on_triangle( v3f p, v3f tri[3], v3f dest ) -{ - v3f ab, ac, ap; - float d1, d2; - - /* Region outside A */ - v3_sub( tri[1], tri[0], ab ); - v3_sub( tri[2], tri[0], ac ); - v3_sub( p, tri[0], ap ); - - d1 = v3_dot(ab,ap); - d2 = v3_dot(ac,ap); - if( d1 <= 0.0f && d2 <= 0.0f ) - { - v3_copy( tri[0], dest ); - v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); - return; - } - - /* Region outside B */ - v3f bp; - float d3, d4; - - v3_sub( p, tri[1], bp ); - d3 = v3_dot( ab, bp ); - d4 = v3_dot( ac, bp ); - - if( d3 >= 0.0f && d4 <= d3 ) - { - v3_copy( tri[1], dest ); - v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); - return; - } - - /* Edge region of AB */ - float vc = d1*d4 - d3*d2; - if( vc <= 0.0f && d1 >= 0.0f && d3 <= 0.0f ) - { - float v = d1 / (d1-d3); - v3_muladds( tri[0], ab, v, dest ); - v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); - return; - } - - /* Region outside C */ - v3f cp; - float d5, d6; - v3_sub( p, tri[2], cp ); - d5 = v3_dot(ab, cp); - d6 = v3_dot(ac, cp); - - if( d6 >= 0.0f && d5 <= d6 ) - { - v3_copy( tri[2], dest ); - v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); - return; - } - - /* Region of AC */ - float vb = d5*d2 - d1*d6; - if( vb <= 0.0f && d2 >= 0.0f && d6 <= 0.0f ) - { - float w = d2 / (d2-d6); - v3_muladds( tri[0], ac, w, dest ); - v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); - return; - } - - /* Region of BC */ - float va = d3*d6 - d5*d4; - if( va <= 0.0f && (d4-d3) >= 0.0f && (d5-d6) >= 0.0f ) - { - float w = (d4-d3) / ((d4-d3) + (d5-d6)); - v3f bc; - v3_sub( tri[2], tri[1], bc ); - v3_muladds( tri[1], bc, w, dest ); - v3_copy( (v3f){INFINITY,INFINITY,INFINITY}, dest ); - return; - } - - /* P inside region, Q via barycentric coordinates uvw */ - float d = 1.0f/(va+vb+vc), - v = vb*d, - w = vc*d; - - v3_muladds( tri[0], ab, v, dest ); - v3_muladds( dest, ac, w, dest ); -} - -static int sphere_vs_triangle( v3f c, float r, v3f tri[3], - v3f co, v3f norm, float *p ) -{ - v3f delta; - closest_on_triangle( c, tri, co ); - - v3_sub( c, co, delta ); - - - float d = v3_length2( delta ); - if( d < r*r ) - { - v3f ab, ac, tn; - v3_sub( tri[1], tri[0], ab ); - v3_sub( tri[2], tri[0], ac ); - v3_cross( ac, ab, tn ); - - if( v3_dot( delta, tn ) > 0.0f ) - v3_muls( delta, -1.0f, delta ); - - vg_line_pt3( co, 0.05f, 0xff00ff00 ); - - d = sqrtf(d); - v3_muls( delta, 1.0f/d, norm ); - - *p = r-d; - return 1; - } - - return 0; -} - static void debug_capsule( m4x3f m, float height, float radius, u32 colour ) { v3f last = { 0.0f, 0.0f, radius };