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;
  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], gate->recv_to_world );
  26    v3_copy( gate->co[1], gate->recv_to_world[3] );
  27    m4x3_mul( gate->recv_to_world, to_local, gate->transport );
  28 }
  29
  30 VG_STATIC void world_gates_init(void)
  31 {
  32    vg_info( "world_gates_init\n" );
  33
  34    shader_model_gate_register();
  35
  36    vg_linear_clear( vg_mem.scratch );
  37    mdl_context *mgate = mdl_load_full( vg_mem.scratch, "models/rs_gate.mdl" );
  38
  39    vg_acquire_thread_sync();
  40    {
  41       mdl_unpack_glmesh( mgate, &world_global.mesh_gate_surface );
  42    }
  43    vg_release_thread_sync();
  44 }
  45
  46 VG_STATIC int render_gate( world_instance *world_inside,
  47                            teleport_gate *gate, camera *cam )
  48 {
  49    v3f viewdir, gatedir;
  50    m3x3_mulv( cam->transform, (v3f){0.0f,0.0f,-1.0f}, viewdir );
  51    m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, gatedir );
  52
  53    v3f v0;
  54    v3_sub( cam->pos, gate->co[0], v0 );
  55
  56    float dist = v3_dot(v0, gatedir);
  57
  58    /* Hard cutoff */
  59    if( dist > 3.0f )
  60       return 0;
  61
  62    if( v3_dist( cam->pos, gate->co[0] ) > 100.0f )
  63       return 0;
  64
  65    {
  66       v3f a,b,c,d;
  67
  68       float sx = gate->dims[0],
  69             sy = gate->dims[1];
  70       m4x3_mulv( gate->to_world, (v3f){-sx,-sy,0.0f}, a );
  71       m4x3_mulv( gate->to_world, (v3f){ sx,-sy,0.0f}, b );
  72       m4x3_mulv( gate->to_world, (v3f){ sx, sy,0.0f}, c );
  73       m4x3_mulv( gate->to_world, (v3f){-sx, sy,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    m3x3_mulv( gate->recv_to_world, (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       m4x3f gate_xform;
 109       m4x3_copy( gate->to_world, gate_xform );
 110       m4x3_scalev( gate_xform, (v3f){ gate->dims[0], gate->dims[1], 1.0f } );
 111
 112       shader_model_gate_use();
 113       shader_model_gate_uPv( cam->mtx.pv );
 114       shader_model_gate_uMdl( gate_xform );
 115       shader_model_gate_uCam( cam->pos );
 116       shader_model_gate_uTime( vg.time*0.25f );
 117       shader_model_gate_uInvRes( (v2f){
 118             1.0f / (float)vg.window_x,
 119             1.0f / (float)vg.window_y });
 120
 121       glEnable( GL_STENCIL_TEST );
 122       glStencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
 123       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 124       glStencilMask( 0xFF );
 125
 126       mesh_bind( &world_global.mesh_gate_surface );
 127       mesh_draw( &world_global.mesh_gate_surface );
 128
 129       glClear( GL_DEPTH_BUFFER_BIT );
 130       glStencilFunc( GL_EQUAL, 1, 0xFF );
 131       glStencilMask( 0x00 );
 132    }
 133
 134    render_world( world_inside, &gate_camera );
 135
 136    {
 137       glDisable( GL_STENCIL_TEST );
 138
 139       render_water_texture( world_inside, &gate_camera );
 140       render_fb_bind( gpipeline.fb_main );
 141
 142       glEnable( GL_STENCIL_TEST );
 143
 144       render_water_surface( world_inside, &gate_camera );
 145
 146       glStencilMask( 0xFF );
 147       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 148       glDisable( GL_STENCIL_TEST );
 149    }
 150
 151    return 1;
 152 }
 153
 154 VG_STATIC int gate_intersect_plane( teleport_gate *gate, v3f pos, v3f last,
 155                                     v2f where )
 156 {
 157    v4f surface;
 158    m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
 159    surface[3] = v3_dot( surface, gate->co[0] );
 160
 161    v3f v0, c, delta, p0;
 162    v3_sub( pos, last, v0 );
 163    float l = v3_length( v0 );
 164
 165    if( l == 0.0f )
 166       return 0;
 167
 168    v3_divs( v0, l, v0 );
 169
 170    v3_muls( surface, surface[3], c );
 171    v3_sub( c, last, delta );
 172
 173    float d = v3_dot( surface, v0 );
 174
 175    if( d > 0.00001f )
 176    {
 177       float t = v3_dot(delta, surface) / d;
 178       if( t >= 0.0f && t <= l )
 179       {
 180          v3f local, rel;
 181          v3_muladds( last, v0, t, local );
 182          v3_sub( gate->co[0], local, rel );
 183
 184          v3f vup, vside;
 185          m3x3_mulv( gate->to_world, (v3f){0.0f,1.0f,0.0f}, vup );
 186          m3x3_mulv( gate->to_world, (v3f){1.0f,0.0f,0.0f}, vside );
 187
 188          where[0] = v3_dot( rel, vside );
 189          where[1] = v3_dot( rel, vup );
 190
 191          return 1;
 192       }
 193    }
 194
 195    return 0;
 196 }
 197
 198 VG_STATIC int gate_intersect( teleport_gate *gate, v3f pos, v3f last )
 199 {
 200    v2f xy;
 201
 202    if( gate_intersect_plane( gate, pos, last, xy ) )
 203    {
 204       if( fabsf(xy[0]) <= gate->dims[0] && fabsf(xy[1]) <= gate->dims[1] )
 205       {
 206          return 1;
 207       }
 208    }
 209
 210    return 0;
 211 }
 212
 213 struct gate_hit
 214 {
 215    struct nonlocal_gate *nonlocal;
 216    struct route_gate    *route;
 217    teleport_gate *gate;
 218 };
 219
 220 /*
 221  * Intersect all gates in the world
 222  */
 223 VG_STATIC int world_intersect_gates( world_instance *world,
 224                                      v3f pos, v3f last, struct gate_hit *hit )
 225 {
 226    for( int i=0; i<world->gate_count; i++ )
 227    {
 228       struct route_gate *rg = &world->gates[i];
 229       teleport_gate *gate = &rg->gate;
 230
 231       if( gate_intersect( gate, pos, last ) )
 232       {
 233          hit->gate = gate;
 234          hit->nonlocal = NULL;
 235          hit->route = rg;
 236          return 1;
 237       }
 238    }
 239
 240    for( int i=0; i<world->nonlocalgate_count; i++ )
 241    {
 242       struct nonlocal_gate *nlg = &world->nonlocal_gates[i];
 243       teleport_gate *gate = &nlg->gate;
 244
 245       if( gate_intersect( gate, pos, last ) )
 246       {
 247          hit->gate = gate;
 248          hit->nonlocal = nlg;
 249          hit->route = NULL;
 250          return 1;
 251      }
 252    }
 253
 254    return 0;
 255 }
 256
 257 #endif /* WORLD_GATE_H */