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    if( v3_dot(v0, gatedir) >= 0.0f )
  56       return 0;
  57
  58    if( v3_dist( cam->pos, gate->co[0] ) > 100.0f )
  59       return 0;
  60
  61    {
  62       v3f a,b,c,d;
  63
  64       float sx = gate->dims[0],
  65             sy = gate->dims[1];
  66       m4x3_mulv( gate->to_world, (v3f){-sx,-sy,0.0f}, a );
  67       m4x3_mulv( gate->to_world, (v3f){ sx,-sy,0.0f}, b );
  68       m4x3_mulv( gate->to_world, (v3f){ sx, sy,0.0f}, c );
  69       m4x3_mulv( gate->to_world, (v3f){-sx, sy,0.0f}, d );
  70
  71       vg_line( a,b, 0xffffa000 );
  72       vg_line( b,c, 0xffffa000 );
  73       vg_line( c,d, 0xffffa000 );
  74       vg_line( d,a, 0xffffa000 );
  75
  76       vg_line2( gate->co[0], gate->co[1], 0xff0000ff, 0x00000000 );
  77    }
  78
  79    /* update gate camera */
  80    static camera gate_view;
  81    gate_view.fov = cam->fov;
  82    gate_view.nearz = 0.1f;
  83    gate_view.farz  = 900.0f;
  84
  85    m4x3_mul( gate->transport, cam->transform, gate_view.transform );
  86    camera_update_view( &gate_view );
  87    camera_update_projection( &gate_view );
  88
  89    /* Add special clipping plane to projection */
  90    v4f surface;
  91    m3x3_mulv( gate->recv_to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
  92    surface[3] = v3_dot( surface, gate->co[1] );
  93
  94    m4x3_mulp( gate_view.transform_inverse, surface, surface );
  95    surface[3] = -fabsf(surface[3]);
  96    m4x4_clip_projection( gate_view.mtx.p, surface );
  97
  98    /* Ready to draw with new camrea */
  99    camera_finalize( &gate_view );
 100
 101    vg_line_pt3( gate_view.transform[3], 0.3f, 0xff00ff00 );
 102    {
 103       m4x3f gate_xform;
 104       m4x3_copy( gate->to_world, gate_xform );
 105       m4x3_scalev( gate_xform, (v3f){ gate->dims[0], gate->dims[1], 1.0f } );
 106
 107       shader_gatelq_use();
 108       shader_gatelq_uPv( cam->mtx.pv );
 109       shader_gatelq_uMdl( gate_xform );
 110       shader_gatelq_uCam( cam->pos );
 111       shader_gatelq_uTime( vg.time*0.25f );
 112       shader_gatelq_uInvRes( (v2f){
 113             1.0f / (float)vg.window_x,
 114             1.0f / (float)vg.window_y });
 115
 116       glEnable( GL_STENCIL_TEST );
 117       glStencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
 118       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 119       glStencilMask( 0xFF );
 120
 121       mesh_bind( &world.mesh_gate_surface );
 122       mesh_draw( &world.mesh_gate_surface );
 123
 124       glClear( GL_DEPTH_BUFFER_BIT );
 125       glStencilFunc( GL_EQUAL, 1, 0xFF );
 126       glStencilMask( 0x00 );
 127    }
 128
 129    render_world( &gate_view );
 130
 131    {
 132       glDisable( GL_STENCIL_TEST );
 133
 134       render_water_texture( &gate_view );
 135       render_fb_bind( gpipeline.fb_main );
 136
 137       glEnable( GL_STENCIL_TEST );
 138
 139       render_water_surface( &gate_view );
 140
 141       glStencilMask( 0xFF );
 142       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 143       glDisable( GL_STENCIL_TEST );
 144    }
 145
 146    return 1;
 147 }
 148
 149 VG_STATIC int gate_intersect( teleport_gate *gate, v3f pos, v3f last )
 150 {
 151    v4f surface;
 152    m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
 153    surface[3] = v3_dot( surface, gate->co[0] );
 154
 155    v3f v0, c, delta, p0;
 156    v3_sub( pos, last, v0 );
 157    float l = v3_length( v0 );
 158
 159    if( l == 0.0f )
 160       return 0;
 161
 162    v3_divs( v0, l, v0 );
 163
 164    v3_muls( surface, surface[3], c );
 165    v3_sub( c, last, delta );
 166
 167    float d = v3_dot( surface, v0 );
 168
 169    if( d > 0.00001f )
 170    {
 171       float t = v3_dot(delta, surface) / d;
 172       if( t >= 0.0f && t <= l )
 173       {
 174          v3f local, rel;
 175          v3_muladds( last, v0, t, local );
 176          v3_sub( gate->co[0], local, rel );
 177
 178          v3f vup, vside;
 179          m3x3_mulv( gate->to_world, (v3f){0.0f,1.0f,0.0f}, vup );
 180          m3x3_mulv( gate->to_world, (v3f){1.0f,0.0f,0.0f}, vside );
 181
 182          v2f xy = { v3_dot( rel, vside ), v3_dot( rel, vup ) };
 183
 184          if( fabsf(xy[0]) <= gate->dims[0] && fabsf(xy[1]) <= gate->dims[1] )
 185          {
 186             return 1;
 187          }
 188       }
 189    }
 190
 191    return 0;
 192 }
 193
 194 #endif /* WORLD_GATE_H */