-static void apply_gravity( v3f vel, float const timestep )
-{
- v3f gravity = { 0.0f, -9.6f, 0.0f };
- v3_muladds( vel, gravity, timestep, vel );
-}
-
-/*
- * Called when launching into the air to predict and adjust trajectories
- */
-static void player_start_air(void)
-{
- struct player_phys *phys = &player.phys;
-
- if( phys->in_air )
- return;
-
- phys->in_air = 1;
-
- float pstep = ktimestep*10.0f;
- float best_velocity_delta = -9999.9f;
- float k_bias = 0.96f;
-
- v3f axis;
- v3_cross( phys->rb.up, phys->rb.v, axis );
- v3_normalize( axis );
- player.land_log_count = 0;
-
- m3x3_identity( phys->vr );
-
- for( int m=-3;m<=12; m++ )
- {
- float vmod = ((float)m / 15.0f)*0.09f;
-
- v3f pco, pco1, pv;
- v3_copy( phys->rb.co, pco );
- v3_muls( phys->rb.v, k_bias, pv );
-
- /*
- * Try different 'rotations' of the velocity to find the best possible
- * landing normal. This conserves magnitude at the expense of slightly
- * unrealistic results
- */
-
- m3x3f vr;
- v4f vr_q;
-
- q_axis_angle( vr_q, axis, vmod );
- q_m3x3( vr_q, vr );
-
- m3x3_mulv( vr, pv, pv );
- v3_muladds( pco, pv, pstep, pco );
-
- for( int i=0; i<50; i++ )
- {
- v3_copy( pco, pco1 );
- apply_gravity( pv, pstep );
-
- m3x3_mulv( vr, pv, pv );
- v3_muladds( pco, pv, pstep, pco );
-
- ray_hit contact;
- v3f vdir;
-
- v3_sub( pco, pco1, vdir );
- contact.dist = v3_length( vdir );
- v3_divs( vdir, contact.dist, vdir);
-
- if( ray_world( pco1, vdir, &contact ))
- {
- float land_delta = v3_dot( pv, contact.normal );
- u32 scolour = (u8)(vg_minf(-land_delta * 2.0f, 255.0f));
-
- /* Bias prediction towords ramps */
- if( ray_hit_is_ramp( &contact ) )
- {
- land_delta *= 0.1f;
- scolour |= 0x0000a000;
- }
-
- if( (land_delta < 0.0f) && (land_delta > best_velocity_delta) )
- {
- best_velocity_delta = land_delta;
-
- v3_copy( contact.pos, player.land_target );
-
- m3x3_copy( vr, phys->vr_pstep );
- q_axis_angle( vr_q, axis, vmod*0.1f );
- q_m3x3( vr_q, phys->vr );
- }
-
- v3_copy( contact.pos,
- player.land_target_log[player.land_log_count] );
- player.land_target_colours[player.land_log_count] =
- 0xff000000 | scolour;
-
- player.land_log_count ++;
-
- break;
- }
- }
- }
-}
-
-/*
- * Main friction interface model
- */
-static void player_physics_control(void)
-{
- struct player_phys *phys = &player.phys;
-
- /*
- * Computing localized friction forces for controlling the character
- * Friction across X is significantly more than Z
- */
-
- v3f vel;
- m3x3_mulv( phys->rb.to_local, phys->rb.v, vel );
- float slip = 0.0f;
-
- if( fabsf(vel[2]) > 0.01f )
- slip = fabsf(-vel[0] / vel[2]) * vg_signf(vel[0]);
-
- if( fabsf( slip ) > 1.2f )
- slip = vg_signf( slip ) * 1.2f;
- phys->slip = slip;
- phys->reverse = -vg_signf(vel[2]);
-
- float substep = ktimestep * 0.2f;
- float fwd_resistance = (vg_get_button( "break" )? 5.0f: 0.02f) * -substep;
-
- for( int i=0; i<5; i++ )
- {
- vel[2] = stable_force( vel[2], vg_signf( vel[2] ) * fwd_resistance );
- vel[0] = stable_force( vel[0],
- vg_signf( vel[0] ) * -k_friction_lat*substep );
- }
-
- static double start_push = 0.0;
- if( vg_get_button_down( "push" ) )
- start_push = vg_time;
-
- if( vg_get_button( "jump" ) )
- {
- phys->jump += ktimestep * k_jump_charge_speed;
-
- if( !phys->jump_charge )
- phys->jump_dir = phys->reverse > 0.0f? 1: 0;
-
- phys->jump_charge = 1;
- }
-
- if( !vg_get_button("break") && vg_get_button( "push" ) )
- {
- player.pushing = 1.0f;
- player.push_time = vg_time-start_push;
-
- float cycle_time = player.push_time*k_push_cycle_rate,
- amt = k_push_accel * (sinf(cycle_time)*0.5f+0.5f)*ktimestep,
- current = v3_length( vel ),
- new_vel = vg_minf( current + amt, k_max_push_speed );
-
- new_vel -= vg_minf(current, k_max_push_speed);
- vel[2] -= new_vel * phys->reverse;
- }
-
- /* Pumping */
- static float previous = 0.0f;
- float delta = previous - phys->grab,
- pump = delta * k_pump_force*ktimestep;
- previous = phys->grab;
-
- v3f p1;
- v3_muladds( phys->rb.co, phys->rb.up, pump, p1 );
- vg_line( phys->rb.co, p1, 0xff0000ff );