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/gatelq.h"
  14 #include "world_water.h"
  15
  16
  17 VG_STATIC void gate_transform_update( teleport_gate *gate )
  18 {
  19    m4x3f to_local;
  20
  21    q_m3x3( gate->q[0], gate->to_world );
  22    v3_copy( gate->co[0], gate->to_world[3] );
  23
  24    m4x3_invert_affine( gate->to_world, to_local );
  25
  26    q_m3x3( gate->q[1], gate->recv_to_world );
  27    v3_copy( gate->co[1], gate->recv_to_world[3] );
  28    m4x3_mul( gate->recv_to_world, to_local, gate->transport );
  29 }
  30
  31 VG_STATIC void world_gates_init(void)
  32 {
  33    vg_info( "world_gates_init\n" );
  34
  35    shader_gatelq_register();
  36
  37    vg_linear_clear( vg_mem.scratch );
  38    mdl_context *mgate = mdl_load_full( vg_mem.scratch, "models/rs_gate.mdl" );
  39
  40    vg_acquire_thread_sync();
  41    {
  42       mdl_unpack_glmesh( mgate, &world.mesh_gate_surface );
  43    }
  44    vg_release_thread_sync();
  45 }
  46
  47 VG_STATIC int render_gate( 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    static camera gate_view;
  85    gate_view.fov = cam->fov;
  86    gate_view.nearz = 0.1f;
  87    gate_view.farz  = 2000.0f;
  88
  89    m4x3_mul( gate->transport, cam->transform, gate_view.transform );
  90    camera_update_view( &gate_view );
  91    camera_update_projection( &gate_view );
  92
  93    /* Add special clipping plane to projection */
  94    v4f surface;
  95    m3x3_mulv( gate->recv_to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
  96    surface[3] = v3_dot( surface, gate->co[1] );
  97
  98    m4x3_mulp( gate_view.transform_inverse, surface, surface );
  99    surface[3] = -fabsf(surface[3]);
 100
 101    if( dist < -0.5f )
 102       m4x4_clip_projection( gate_view.mtx.p, surface );
 103
 104    /* Ready to draw with new camrea */
 105    camera_finalize( &gate_view );
 106
 107    vg_line_pt3( gate_view.transform[3], 0.3f, 0xff00ff00 );
 108    {
 109       m4x3f gate_xform;
 110       m4x3_copy( gate->to_world, gate_xform );
 111       m4x3_scalev( gate_xform, (v3f){ gate->dims[0], gate->dims[1], 1.0f } );
 112
 113       shader_gatelq_use();
 114       shader_gatelq_uPv( cam->mtx.pv );
 115       shader_gatelq_uMdl( gate_xform );
 116       shader_gatelq_uCam( cam->pos );
 117       shader_gatelq_uTime( vg.time*0.25f );
 118       shader_gatelq_uInvRes( (v2f){
 119             1.0f / (float)vg.window_x,
 120             1.0f / (float)vg.window_y });
 121
 122       glEnable( GL_STENCIL_TEST );
 123       glStencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
 124       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 125       glStencilMask( 0xFF );
 126
 127       mesh_bind( &world.mesh_gate_surface );
 128       mesh_draw( &world.mesh_gate_surface );
 129
 130       glClear( GL_DEPTH_BUFFER_BIT );
 131       glStencilFunc( GL_EQUAL, 1, 0xFF );
 132       glStencilMask( 0x00 );
 133    }
 134
 135    render_world( &gate_view );
 136
 137    {
 138       glDisable( GL_STENCIL_TEST );
 139
 140       render_water_texture( &gate_view );
 141       render_fb_bind( gpipeline.fb_main );
 142
 143       glEnable( GL_STENCIL_TEST );
 144
 145       render_water_surface( &gate_view );
 146
 147       glStencilMask( 0xFF );
 148       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 149       glDisable( GL_STENCIL_TEST );
 150    }
 151
 152    return 1;
 153 }
 154
 155 VG_STATIC int gate_intersect_plane( teleport_gate *gate, v3f pos, v3f last,
 156                                     v2f where )
 157 {
 158    v4f surface;
 159    m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
 160    surface[3] = v3_dot( surface, gate->co[0] );
 161
 162    v3f v0, c, delta, p0;
 163    v3_sub( pos, last, v0 );
 164    float l = v3_length( v0 );
 165
 166    if( l == 0.0f )
 167       return 0;
 168
 169    v3_divs( v0, l, v0 );
 170
 171    v3_muls( surface, surface[3], c );
 172    v3_sub( c, last, delta );
 173
 174    float d = v3_dot( surface, v0 );
 175
 176    if( d > 0.00001f )
 177    {
 178       float t = v3_dot(delta, surface) / d;
 179       if( t >= 0.0f && t <= l )
 180       {
 181          v3f local, rel;
 182          v3_muladds( last, v0, t, local );
 183          v3_sub( gate->co[0], local, rel );
 184
 185          v3f vup, vside;
 186          m3x3_mulv( gate->to_world, (v3f){0.0f,1.0f,0.0f}, vup );
 187          m3x3_mulv( gate->to_world, (v3f){1.0f,0.0f,0.0f}, vside );
 188
 189          where[0] = v3_dot( rel, vside );
 190          where[1] = v3_dot( rel, vup );
 191
 192          return 1;
 193       }
 194    }
 195
 196    return 0;
 197 }
 198
 199 VG_STATIC int gate_intersect( teleport_gate *gate, v3f pos, v3f last )
 200 {
 201    v2f xy;
 202
 203    if( gate_intersect_plane( gate, pos, last, xy ) )
 204    {
 205       if( fabsf(xy[0]) <= gate->dims[0] && fabsf(xy[1]) <= gate->dims[1] )
 206       {
 207          return 1;
 208       }
 209    }
 210
 211    return 0;
 212 }
 213
 214 /*
 215  * Intersect all gates in the world
 216  */
 217 VG_STATIC teleport_gate *world_intersect_gates( v3f pos, v3f last )
 218 {
 219    for( int i=0; i<world.gate_count; i++ )
 220    {
 221       struct route_gate *rg = &world.gates[i];
 222       teleport_gate *gate = &rg->gate;
 223
 224       if( gate_intersect( gate, pos, last ) )
 225          return gate;
 226    }
 227
 228    return NULL;
 229 }
 230
 231 #endif /* WORLD_GATE_H */