world_gate.h

   1 /*
   2  * Copyright (C) 2021-2022 Mt.ZERO Software, Harry Godden - All Rights Reserved
   3  */
   4
   5 #ifndef WORLD_GATE_H
   6 #define WORLD_GATE_H
   7
   8 #include "common.h"
   9 #include "model.h"
  10 #include "render.h"
  11 #include "camera.h"
  12
  13 #include "shaders/model_gate.h"
  14 #include "world_water.h"
  15
  16 VG_STATIC void gate_transform_update( teleport_gate *gate )
  17 {
  18    m4x3f to_local, recv_to_world;
  19
  20    q_m3x3( gate->q[0], gate->to_world );
  21    v3_copy( gate->co[0], gate->to_world[3] );
  22
  23    m4x3_invert_affine( gate->to_world, to_local );
  24
  25    q_m3x3( gate->q[1], recv_to_world );
  26    v3_copy( gate->co[1], recv_to_world[3] );
  27    m4x3_mul( recv_to_world, to_local, gate->transport );
  28
  29    m4x3_scalev( gate->to_world, (v3f){ gate->dims[0], gate->dims[1], 1.0f } );
  30 }
  31
  32 VG_STATIC void world_gates_init(void)
  33 {
  34    vg_info( "world_gates_init\n" );
  35
  36    shader_model_gate_register();
  37
  38    vg_linear_clear( vg_mem.scratch );
  39    mdl_context *mgate = mdl_load_full( vg_mem.scratch, "models/rs_gate.mdl" );
  40
  41    vg_acquire_thread_sync();
  42    {
  43       mdl_unpack_glmesh( mgate, &world_global.mesh_gate_surface );
  44    }
  45    vg_release_thread_sync();
  46 }
  47
  48 VG_STATIC int render_gate( world_instance *world_inside,
  49                            teleport_gate *gate, camera *cam )
  50 {
  51    v3f viewdir, gatedir;
  52    m3x3_mulv( cam->transform, (v3f){0.0f,0.0f,-1.0f}, viewdir );
  53    q_mulv( gate->q[0], (v3f){0.0f,0.0f,-1.0f}, gatedir );
  54
  55    v3f v0;
  56    v3_sub( cam->pos, gate->co[0], v0 );
  57
  58    float dist = v3_dot(v0, gatedir);
  59
  60    /* Hard cutoff */
  61    if( dist > 3.0f )
  62       return 0;
  63
  64    if( v3_dist( cam->pos, gate->co[0] ) > 100.0f )
  65       return 0;
  66
  67    {
  68       v3f a,b,c,d;
  69
  70       m4x3_mulv( gate->to_world, (v3f){-1.0f,-1.0f,0.0f}, a );
  71       m4x3_mulv( gate->to_world, (v3f){ 1.0f,-1.0f,0.0f}, b );
  72       m4x3_mulv( gate->to_world, (v3f){ 1.0f, 1.0f,0.0f}, c );
  73       m4x3_mulv( gate->to_world, (v3f){-1.0f, 1.0f,0.0f}, d );
  74
  75       vg_line( a,b, 0xffffa000 );
  76       vg_line( b,c, 0xffffa000 );
  77       vg_line( c,d, 0xffffa000 );
  78       vg_line( d,a, 0xffffa000 );
  79
  80       vg_line2( gate->co[0], gate->co[1], 0xff0000ff, 0x00000000 );
  81    }
  82
  83    /* update gate camera */
  84    gate_camera.fov = cam->fov;
  85    gate_camera.nearz = 0.1f;
  86    gate_camera.farz  = 2000.0f;
  87
  88    m4x3_mul( gate->transport, cam->transform, gate_camera.transform );
  89    camera_update_view( &gate_camera );
  90    camera_update_projection( &gate_camera );
  91
  92    /* Add special clipping plane to projection */
  93    v4f surface;
  94    q_mulv( gate->q[1], (v3f){0.0f,0.0f,-1.0f}, surface );
  95    surface[3] = v3_dot( surface, gate->co[1] );
  96
  97    m4x3_mulp( gate_camera.transform_inverse, surface, surface );
  98    surface[3] = -fabsf(surface[3]);
  99
 100    if( dist < -0.5f )
 101       m4x4_clip_projection( gate_camera.mtx.p, surface );
 102
 103    /* Ready to draw with new camrea */
 104    camera_finalize( &gate_camera );
 105
 106    vg_line_pt3( gate_camera.transform[3], 0.3f, 0xff00ff00 );
 107    {
 108       shader_model_gate_use();
 109       shader_model_gate_uPv( cam->mtx.pv );
 110       shader_model_gate_uMdl( gate->to_world );
 111       shader_model_gate_uCam( cam->pos );
 112       shader_model_gate_uTime( vg.time*0.25f );
 113       shader_model_gate_uInvRes( (v2f){
 114             1.0f / (float)vg.window_x,
 115             1.0f / (float)vg.window_y });
 116
 117       glEnable( GL_STENCIL_TEST );
 118       glStencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
 119       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 120       glStencilMask( 0xFF );
 121
 122       mesh_bind( &world_global.mesh_gate_surface );
 123       mesh_draw( &world_global.mesh_gate_surface );
 124
 125       glClear( GL_DEPTH_BUFFER_BIT );
 126       glStencilFunc( GL_EQUAL, 1, 0xFF );
 127       glStencilMask( 0x00 );
 128    }
 129
 130    render_world( world_inside, &gate_camera );
 131
 132    {
 133       glDisable( GL_STENCIL_TEST );
 134
 135       render_water_texture( world_inside, &gate_camera );
 136       render_fb_bind( gpipeline.fb_main );
 137
 138       glEnable( GL_STENCIL_TEST );
 139
 140       render_water_surface( world_inside, &gate_camera );
 141
 142       glStencilMask( 0xFF );
 143       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 144       glDisable( GL_STENCIL_TEST );
 145    }
 146
 147    return 1;
 148 }
 149
 150 VG_STATIC int gate_intersect_plane( teleport_gate *gate, v3f pos, v3f last,
 151                                     v2f where )
 152 {
 153    v4f surface;
 154    q_mulv( gate->q[0], (v3f){0.0f,0.0f,-1.0f}, surface );
 155    surface[3] = v3_dot( surface, gate->co[0] );
 156
 157    v3f v0, c, delta, p0;
 158    v3_sub( pos, last, v0 );
 159    float l = v3_length( v0 );
 160
 161    if( l == 0.0f )
 162       return 0;
 163
 164    v3_divs( v0, l, v0 );
 165
 166    v3_muls( surface, surface[3], c );
 167    v3_sub( c, last, delta );
 168
 169    float d = v3_dot( surface, v0 );
 170
 171    if( d > 0.00001f )
 172    {
 173       float t = v3_dot(delta, surface) / d;
 174       if( t >= 0.0f && t <= l )
 175       {
 176          v3f local, rel;
 177          v3_muladds( last, v0, t, local );
 178          v3_sub( gate->co[0], local, rel );
 179
 180          where[0] = v3_dot( rel, gate->to_world[0] );
 181          where[1] = v3_dot( rel, gate->to_world[1] );
 182
 183          where[0] /= v3_dot( gate->to_world[0], gate->to_world[0] );
 184          where[1] /= v3_dot( gate->to_world[1], gate->to_world[1] );
 185
 186          return 1;
 187       }
 188    }
 189
 190    return 0;
 191 }
 192
 193 VG_STATIC int gate_intersect( teleport_gate *gate, v3f pos, v3f last )
 194 {
 195    v2f xy;
 196
 197    if( gate_intersect_plane( gate, pos, last, xy ) )
 198    {
 199       if( fabsf(xy[0]) <= 1.0f && fabsf(xy[1]) <= 1.0f )
 200       {
 201          return 1;
 202       }
 203    }
 204
 205    return 0;
 206 }
 207
 208 struct gate_hit
 209 {
 210    struct nonlocal_gate *nonlocal;
 211    struct route_gate    *route;
 212    teleport_gate *gate;
 213 };
 214
 215 /*
 216  * Intersect all gates in the world
 217  */
 218 VG_STATIC int world_intersect_gates( world_instance *world,
 219                                      v3f pos, v3f last, struct gate_hit *hit )
 220 {
 221    for( int i=0; i<world->gate_count; i++ )
 222    {
 223       struct route_gate *rg = &world->gates[i];
 224       teleport_gate *gate = &rg->gate;
 225
 226       if( gate_intersect( gate, pos, last ) )
 227       {
 228          hit->gate = gate;
 229          hit->nonlocal = NULL;
 230          hit->route = rg;
 231          return 1;
 232       }
 233    }
 234
 235    for( int i=0; i<world->nonlocalgate_count; i++ )
 236    {
 237       struct nonlocal_gate *nlg = &world->nonlocal_gates[i];
 238       teleport_gate *gate = &nlg->gate;
 239
 240       if( gate_intersect( gate, pos, last ) )
 241       {
 242          hit->gate = gate;
 243          hit->nonlocal = nlg;
 244          hit->route = NULL;
 245          return 1;
 246      }
 247    }
 248
 249    return 0;
 250 }
 251
 252 #endif /* WORLD_GATE_H */