--- /dev/null
+#pragma once
+#include "vg_rigidbody.h"
+#include "vg_rigidbody_constraints.h"
+#include "vg_m.h"
+#include "vg_lines.h"
+
+/*
+ * -----------------------------------------------------------------------------
+ * Constraints
+ * -----------------------------------------------------------------------------
+ */
+
+void rb_debug_position_constraints( rb_constr_pos *buffer, int len )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_pos *constr = &buffer[i];
+ rigidbody *rba = constr->rba, *rbb = constr->rbb;
+
+ v3f wca, wcb;
+ m3x3_mulv( rba->to_world, constr->lca, wca );
+ m3x3_mulv( rbb->to_world, constr->lcb, wcb );
+
+ v3f p0, p1;
+ v3_add( wca, rba->co, p0 );
+ v3_add( wcb, rbb->co, p1 );
+ vg_line_point( p0, 0.0025f, 0xff000000 );
+ vg_line_point( p1, 0.0025f, 0xffffffff );
+ vg_line2( p0, p1, 0xff000000, 0xffffffff );
+ }
+}
+
+void rb_presolve_swingtwist_constraints( rb_constr_swingtwist *buf, int len )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[ i ];
+
+ v3f vx, vy, va, vxb, axis, center;
+
+ m3x3_mulv( st->rba->to_world, st->conevx, vx );
+ m3x3_mulv( st->rbb->to_world, st->conevxb, vxb );
+ m3x3_mulv( st->rba->to_world, st->conevy, vy );
+ m3x3_mulv( st->rbb->to_world, st->coneva, va );
+ m4x3_mulv( st->rba->to_world, st->view_offset, center );
+ v3_cross( vy, vx, axis );
+
+ /* Constraint violated ? */
+ float fx = v3_dot( vx, va ), /* projection world */
+ fy = v3_dot( vy, va ),
+ fn = v3_dot( va, axis ),
+
+ rx = st->conevx[3], /* elipse radii */
+ ry = st->conevy[3],
+
+ lx = fx/rx, /* projection local (fn==lz) */
+ ly = fy/ry;
+
+ st->tangent_violation = ((lx*lx + ly*ly) > fn*fn) || (fn <= 0.0f);
+ if( st->tangent_violation ){
+ /* Calculate a good position and the axis to solve on */
+ v2f closest, tangent,
+ p = { fx/fabsf(fn), fy/fabsf(fn) };
+
+ closest_point_elipse( p, (v2f){rx,ry}, closest );
+ tangent[0] = -closest[1] / (ry*ry);
+ tangent[1] = closest[0] / (rx*rx);
+ v2_normalize( tangent );
+
+ v3f v0, v1;
+ v3_muladds( axis, vx, closest[0], v0 );
+ v3_muladds( v0, vy, closest[1], v0 );
+ v3_normalize( v0 );
+
+ v3_muls( vx, tangent[0], v1 );
+ v3_muladds( v1, vy, tangent[1], v1 );
+
+ v3_copy( v0, st->tangent_target );
+ v3_copy( v1, st->tangent_axis );
+
+ /* calculate mass */
+ v3f aIw, bIw;
+ m3x3_mulv( st->rba->iIw, st->tangent_axis, aIw );
+ m3x3_mulv( st->rbb->iIw, st->tangent_axis, bIw );
+ st->tangent_mass = 1.0f / (v3_dot( st->tangent_axis, aIw ) +
+ v3_dot( st->tangent_axis, bIw ));
+
+ float angle = v3_dot( va, st->tangent_target );
+ }
+
+ v3f refaxis;
+ v3_cross( vy, va, refaxis ); /* our default rotation */
+ v3_normalize( refaxis );
+
+ float angle = v3_dot( refaxis, vxb );
+ st->axis_violation = fabsf(angle) < st->conet;
+
+ if( st->axis_violation ){
+ v3f dir_test;
+ v3_cross( refaxis, vxb, dir_test );
+
+ if( v3_dot(dir_test, va) < 0.0f )
+ st->axis_violation = -st->axis_violation;
+
+ float newang = (float)st->axis_violation * acosf(st->conet-0.0001f);
+
+ v3f refaxis_up;
+ v3_cross( va, refaxis, refaxis_up );
+ v3_muls( refaxis_up, sinf(newang), st->axis_target );
+ v3_muladds( st->axis_target, refaxis, -cosf(newang), st->axis_target );
+
+ /* calculate mass */
+ v3_copy( va, st->axis );
+ v3f aIw, bIw;
+ m3x3_mulv( st->rba->iIw, st->axis, aIw );
+ m3x3_mulv( st->rbb->iIw, st->axis, bIw );
+ st->axis_mass = 1.0f / (v3_dot( st->axis, aIw ) +
+ v3_dot( st->axis, bIw ));
+ }
+ }
+}
+
+void rb_debug_swingtwist_constraints( rb_constr_swingtwist *buf, int len )
+{
+ float size = 0.12f;
+
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[ i ];
+
+ v3f vx, vxb, vy, va, axis, center;
+
+ m3x3_mulv( st->rba->to_world, st->conevx, vx );
+ m3x3_mulv( st->rbb->to_world, st->conevxb, vxb );
+ m3x3_mulv( st->rba->to_world, st->conevy, vy );
+ m3x3_mulv( st->rbb->to_world, st->coneva, va );
+ m4x3_mulv( st->rba->to_world, st->view_offset, center );
+ v3_cross( vy, vx, axis );
+
+ float rx = st->conevx[3], /* elipse radii */
+ ry = st->conevy[3];
+
+ v3f p0, p1;
+ v3_muladds( center, va, size, p1 );
+ vg_line( center, p1, 0xffffffff );
+ vg_line_point( p1, 0.00025f, 0xffffffff );
+
+ if( st->tangent_violation ){
+ v3_muladds( center, st->tangent_target, size, p0 );
+
+ vg_line( center, p0, 0xff00ff00 );
+ vg_line_point( p0, 0.00025f, 0xff00ff00 );
+ vg_line( p1, p0, 0xff000000 );
+ }
+
+ for( int x=0; x<32; x++ ){
+ float t0 = ((float)x * (1.0f/32.0f)) * VG_TAUf,
+ t1 = (((float)x+1.0f) * (1.0f/32.0f)) * VG_TAUf,
+ c0 = cosf( t0 ),
+ s0 = sinf( t0 ),
+ c1 = cosf( t1 ),
+ s1 = sinf( t1 );
+
+ v3f v0, v1;
+ v3_muladds( axis, vx, c0*rx, v0 );
+ v3_muladds( v0, vy, s0*ry, v0 );
+ v3_muladds( axis, vx, c1*rx, v1 );
+ v3_muladds( v1, vy, s1*ry, v1 );
+
+ v3_normalize( v0 );
+ v3_normalize( v1 );
+
+ v3_muladds( center, v0, size, p0 );
+ v3_muladds( center, v1, size, p1 );
+
+ u32 col0r = fabsf(c0) * 255.0f,
+ col0g = fabsf(s0) * 255.0f,
+ col1r = fabsf(c1) * 255.0f,
+ col1g = fabsf(s1) * 255.0f,
+ col = st->tangent_violation? 0xff0000ff: 0xff000000,
+ col0 = col | (col0r<<16) | (col0g << 8),
+ col1 = col | (col1r<<16) | (col1g << 8);
+
+ vg_line2( center, p0, VG__NONE, col0 );
+ vg_line2( p0, p1, col0, col1 );
+ }
+
+ /* Draw twist */
+ v3_muladds( center, va, size, p0 );
+ v3_muladds( p0, vxb, size, p1 );
+
+ vg_line( p0, p1, 0xff0000ff );
+
+ if( st->axis_violation ){
+ v3_muladds( p0, st->axis_target, size*1.25f, p1 );
+ vg_line( p0, p1, 0xffffff00 );
+ vg_line_point( p1, 0.0025f, 0xffffff80 );
+ }
+
+ v3f refaxis;
+ v3_cross( vy, va, refaxis ); /* our default rotation */
+ v3_normalize( refaxis );
+ v3f refaxis_up;
+ v3_cross( va, refaxis, refaxis_up );
+ float newang = acosf(st->conet-0.0001f);
+
+ v3_muladds( p0, refaxis_up, sinf(newang)*size, p1 );
+ v3_muladds( p1, refaxis, -cosf(newang)*size, p1 );
+ vg_line( p0, p1, 0xff000000 );
+
+ v3_muladds( p0, refaxis_up, sinf(-newang)*size, p1 );
+ v3_muladds( p1, refaxis, -cosf(-newang)*size, p1 );
+ vg_line( p0, p1, 0xff404040 );
+ }
+}
+
+void rb_solve_position_constraints( rb_constr_pos *buf, int len )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_pos *constr = &buf[i];
+ rigidbody *rba = constr->rba, *rbb = constr->rbb;
+
+ v3f wa, wb;
+ m3x3_mulv( rba->to_world, constr->lca, wa );
+ m3x3_mulv( rbb->to_world, constr->lcb, wb );
+
+ m3x3f ssra, ssrat, ssrb, ssrbt;
+
+ m3x3_skew_symetric( ssrat, wa );
+ m3x3_skew_symetric( ssrbt, wb );
+ m3x3_transpose( ssrat, ssra );
+ m3x3_transpose( ssrbt, ssrb );
+
+ v3f b, b_wa, b_wb, b_a, b_b;
+ m3x3_mulv( ssra, rba->w, b_wa );
+ m3x3_mulv( ssrb, rbb->w, b_wb );
+ v3_add( rba->v, b_wa, b );
+ v3_sub( b, rbb->v, b );
+ v3_sub( b, b_wb, b );
+ v3_muls( b, -1.0f, b );
+
+ m3x3f invMa, invMb;
+ m3x3_diagonal( invMa, rba->inv_mass );
+ m3x3_diagonal( invMb, rbb->inv_mass );
+
+ m3x3f ia, ib;
+ m3x3_mul( ssra, rba->iIw, ia );
+ m3x3_mul( ia, ssrat, ia );
+ m3x3_mul( ssrb, rbb->iIw, ib );
+ m3x3_mul( ib, ssrbt, ib );
+
+ m3x3f cma, cmb;
+ m3x3_add( invMa, ia, cma );
+ m3x3_add( invMb, ib, cmb );
+
+ m3x3f A;
+ m3x3_add( cma, cmb, A );
+
+ /* Solve Ax = b ( A^-1*b = x ) */
+ v3f impulse;
+ m3x3f invA;
+ m3x3_inv( A, invA );
+ m3x3_mulv( invA, b, impulse );
+
+ v3f delta_va, delta_wa, delta_vb, delta_wb;
+ m3x3f iwa, iwb;
+ m3x3_mul( rba->iIw, ssrat, iwa );
+ m3x3_mul( rbb->iIw, ssrbt, iwb );
+
+ m3x3_mulv( invMa, impulse, delta_va );
+ m3x3_mulv( invMb, impulse, delta_vb );
+ m3x3_mulv( iwa, impulse, delta_wa );
+ m3x3_mulv( iwb, impulse, delta_wb );
+
+ v3_add( rba->v, delta_va, rba->v );
+ v3_add( rba->w, delta_wa, rba->w );
+ v3_sub( rbb->v, delta_vb, rbb->v );
+ v3_sub( rbb->w, delta_wb, rbb->w );
+ }
+}
+
+void rb_solve_swingtwist_constraints( rb_constr_swingtwist *buf, int len )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[ i ];
+
+ if( !st->axis_violation )
+ continue;
+
+ float rv = v3_dot( st->axis, st->rbb->w ) -
+ v3_dot( st->axis, st->rba->w );
+
+ if( rv * (float)st->axis_violation > 0.0f )
+ continue;
+
+ v3f impulse, wa, wb;
+ v3_muls( st->axis, rv*st->axis_mass, impulse );
+ m3x3_mulv( st->rba->iIw, impulse, wa );
+ v3_add( st->rba->w, wa, st->rba->w );
+
+ v3_muls( impulse, -1.0f, impulse );
+ m3x3_mulv( st->rbb->iIw, impulse, wb );
+ v3_add( st->rbb->w, wb, st->rbb->w );
+
+ float rv2 = v3_dot( st->axis, st->rbb->w ) -
+ v3_dot( st->axis, st->rba->w );
+ }
+
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[ i ];
+
+ if( !st->tangent_violation )
+ continue;
+
+ float rv = v3_dot( st->tangent_axis, st->rbb->w ) -
+ v3_dot( st->tangent_axis, st->rba->w );
+
+ if( rv > 0.0f )
+ continue;
+
+ v3f impulse, wa, wb;
+ v3_muls( st->tangent_axis, rv*st->tangent_mass, impulse );
+ m3x3_mulv( st->rba->iIw, impulse, wa );
+ v3_add( st->rba->w, wa, st->rba->w );
+
+ v3_muls( impulse, -1.0f, impulse );
+ m3x3_mulv( st->rbb->iIw, impulse, wb );
+ v3_add( st->rbb->w, wb, st->rbb->w );
+
+ float rv2 = v3_dot( st->tangent_axis, st->rbb->w ) -
+ v3_dot( st->tangent_axis, st->rba->w );
+ }
+}
+
+/* debugging */
+void rb_postsolve_swingtwist_constraints( rb_constr_swingtwist *buf, u32 len )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[ i ];
+
+ if( !st->axis_violation ){
+ st->conv_axis = 0.0f;
+ continue;
+ }
+
+ f32 rv = v3_dot( st->axis, st->rbb->w ) -
+ v3_dot( st->axis, st->rba->w );
+
+ if( rv * (f32)st->axis_violation > 0.0f )
+ st->conv_axis = 0.0f;
+ else
+ st->conv_axis = rv;
+ }
+
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[ i ];
+
+ if( !st->tangent_violation ){
+ st->conv_tangent = 0.0f;
+ continue;
+ }
+
+ f32 rv = v3_dot( st->tangent_axis, st->rbb->w ) -
+ v3_dot( st->tangent_axis, st->rba->w );
+
+ if( rv > 0.0f )
+ st->conv_tangent = 0.0f;
+ else
+ st->conv_tangent = rv;
+ }
+}
+
+void rb_solve_constr_angle( rigidbody *rba, rigidbody *rbb, v3f ra, v3f rb )
+{
+ m3x3f ssra, ssrb, ssrat, ssrbt;
+ m3x3f cma, cmb;
+
+ m3x3_skew_symetric( ssrat, ra );
+ m3x3_skew_symetric( ssrbt, rb );
+ m3x3_transpose( ssrat, ssra );
+ m3x3_transpose( ssrbt, ssrb );
+
+ m3x3_mul( ssra, rba->iIw, cma );
+ m3x3_mul( cma, ssrat, cma );
+ m3x3_mul( ssrb, rbb->iIw, cmb );
+ m3x3_mul( cmb, ssrbt, cmb );
+
+ m3x3f A, invA;
+ m3x3_add( cma, cmb, A );
+ m3x3_inv( A, invA );
+
+ v3f b_wa, b_wb, b;
+ m3x3_mulv( ssra, rba->w, b_wa );
+ m3x3_mulv( ssrb, rbb->w, b_wb );
+ v3_add( b_wa, b_wb, b );
+ v3_negate( b, b );
+
+ v3f impulse;
+ m3x3_mulv( invA, b, impulse );
+
+ v3f delta_wa, delta_wb;
+ m3x3f iwa, iwb;
+ m3x3_mul( rba->iIw, ssrat, iwa );
+ m3x3_mul( rbb->iIw, ssrbt, iwb );
+ m3x3_mulv( iwa, impulse, delta_wa );
+ m3x3_mulv( iwb, impulse, delta_wb );
+ v3_add( rba->w, delta_wa, rba->w );
+ v3_sub( rbb->w, delta_wb, rbb->w );
+}
+
+void rb_correct_position_constraints( rb_constr_pos *buf, int len, f32 amt )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_pos *constr = &buf[i];
+ rigidbody *rba = constr->rba, *rbb = constr->rbb;
+
+ v3f p0, p1, d;
+ m3x3_mulv( rba->to_world, constr->lca, p0 );
+ m3x3_mulv( rbb->to_world, constr->lcb, p1 );
+ v3_add( rba->co, p0, p0 );
+ v3_add( rbb->co, p1, p1 );
+ v3_sub( p1, p0, d );
+
+#if 1
+ v3_muladds( rbb->co, d, -1.0f * amt, rbb->co );
+ rb_update_matrices( rbb );
+#else
+ f32 mt = 1.0f/(rba->inv_mass+rbb->inv_mass),
+ a = mt * (k_phys_baumgarte/k_rb_delta);
+
+ v3_muladds( rba->v, d, a* rba->inv_mass, rba->v );
+ v3_muladds( rbb->v, d, a*-rbb->inv_mass, rbb->v );
+#endif
+ }
+}
+
+void rb_correct_swingtwist_constraints( rb_constr_swingtwist *buf,
+ int len, float amt )
+{
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[i];
+
+ if( !st->tangent_violation )
+ continue;
+
+ v3f va;
+ m3x3_mulv( st->rbb->to_world, st->coneva, va );
+
+ f32 angle = v3_dot( va, st->tangent_target );
+
+ if( fabsf(angle) < 0.9999f ){
+ v3f axis;
+ v3_cross( va, st->tangent_target, axis );
+#if 1
+ angle = acosf(angle) * amt;
+ v4f correction;
+ q_axis_angle( correction, axis, angle );
+ q_mul( correction, st->rbb->q, st->rbb->q );
+ q_normalize( st->rbb->q );
+ rb_update_matrices( st->rbb );
+#else
+ f32 mt = 1.0f/(st->rba->inv_mass+st->rbb->inv_mass),
+ wa = mt * acosf(angle) * (k_phys_baumgarte/k_rb_delta);
+ //v3_muladds( st->rba->w, axis, wa*-st->rba->inv_mass, st->rba->w );
+ v3_muladds( st->rbb->w, axis, wa* st->rbb->inv_mass, st->rbb->w );
+#endif
+ }
+ }
+
+ for( int i=0; i<len; i++ ){
+ rb_constr_swingtwist *st = &buf[i];
+
+ if( !st->axis_violation )
+ continue;
+
+ v3f vxb;
+ m3x3_mulv( st->rbb->to_world, st->conevxb, vxb );
+
+ f32 angle = v3_dot( vxb, st->axis_target );
+
+ if( fabsf(angle) < 0.9999f ){
+ v3f axis;
+ v3_cross( vxb, st->axis_target, axis );
+
+#if 1
+ angle = acosf(angle) * amt;
+ v4f correction;
+ q_axis_angle( correction, axis, angle );
+ q_mul( correction, st->rbb->q, st->rbb->q );
+ q_normalize( st->rbb->q );
+ rb_update_matrices( st->rbb );
+#else
+ f32 mt = 1.0f/(st->rba->inv_mass+st->rbb->inv_mass),
+ wa = mt * acosf(angle) * (k_phys_baumgarte/k_rb_delta);
+ //v3_muladds( st->rba->w, axis, wa*-0.5f, st->rba->w );
+ v3_muladds( st->rbb->w, axis, wa* st->rbb->inv_mass, st->rbb->w );
+#endif
+ }
+ }
+}
projects / vg.git / blobdiff