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
  12 #include "shaders/gatelq.h"
  13 #include "world_water.h"
  14
  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_gatelq_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.mesh_gate_surface );
  42    }
  43    vg_release_thread_sync();
  44 }
  45
  46 VG_STATIC int render_gate( teleport_gate *gate, v3f viewpos, m4x3f camera )
  47 {
  48    v3f viewdir, gatedir;
  49    m3x3_mulv( camera, (v3f){0.0f,0.0f,-1.0f}, viewdir );
  50    m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, gatedir );
  51
  52    v3f v0;
  53    v3_sub( viewpos, gate->co[0], v0 );
  54    if( v3_dot(v0, gatedir) >= 0.0f )
  55       return 0;
  56
  57    if( v3_dist( viewpos, gate->co[0] ) > 100.0f )
  58       return 0;
  59
  60    v3f a,b,c,d;
  61
  62    float sx = gate->dims[0],
  63          sy = gate->dims[1];
  64    m4x3_mulv( gate->to_world, (v3f){-sx,-sy,0.0f}, a );
  65    m4x3_mulv( gate->to_world, (v3f){ sx,-sy,0.0f}, b );
  66    m4x3_mulv( gate->to_world, (v3f){ sx, sy,0.0f}, c );
  67    m4x3_mulv( gate->to_world, (v3f){-sx, sy,0.0f}, d );
  68
  69    vg_line( a,b, 0xffffa000 );
  70    vg_line( b,c, 0xffffa000 );
  71    vg_line( c,d, 0xffffa000 );
  72    vg_line( d,a, 0xffffa000 );
  73
  74    vg_line2( gate->co[0], gate->co[1], 0xff0000ff, 0x00000000 );
  75
  76    m4x3f cam_new;
  77    m4x3_mul( gate->transport, camera, cam_new );
  78
  79    vg_line_pt3( cam_new[3], 0.3f, 0xff00ff00 );
  80
  81    m4x3f gate_xform;
  82    m4x3_copy( gate->to_world, gate_xform );
  83    m4x3_scalev( gate_xform, (v3f){ gate->dims[0], gate->dims[1], 1.0f } );
  84
  85    m4x3f inverse;
  86    m4x3_invert_affine( cam_new, inverse );
  87
  88    m4x4f view;
  89    m4x3_expand( inverse, view );
  90
  91    v4f surface;
  92    m3x3_mulv( gate->recv_to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
  93    surface[3] = v3_dot( surface, gate->co[1] );
  94
  95    m4x4f projection;
  96    pipeline_projection( projection, 0.1f, 900.0f );
  97
  98    m4x3_mulp( inverse, surface, surface );
  99    surface[3] = -fabsf(surface[3]);
 100    plane_clip_projection( projection, surface );
 101
 102    m4x4_mul( projection, view, projection );
 103
 104    {
 105       shader_gatelq_use();
 106       shader_gatelq_uPv( vg.pv );
 107       shader_gatelq_uMdl( gate_xform );
 108       shader_gatelq_uCam( viewpos );
 109       shader_gatelq_uTime( vg.time*0.25f );
 110       shader_gatelq_uInvRes( (v2f){
 111             1.0f / (float)vg.window_x,
 112             1.0f / (float)vg.window_y });
 113
 114       glEnable( GL_STENCIL_TEST );
 115       glStencilOp( GL_KEEP, GL_KEEP, GL_REPLACE );
 116       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 117       glStencilMask( 0xFF );
 118
 119       mesh_bind( &world.mesh_gate_surface );
 120       mesh_draw( &world.mesh_gate_surface );
 121
 122       glClear( GL_DEPTH_BUFFER_BIT );
 123       glStencilFunc( GL_EQUAL, 1, 0xFF );
 124       glStencilMask( 0x00 );
 125    }
 126
 127    render_world( projection, cam_new );
 128
 129    {
 130       glDisable( GL_STENCIL_TEST );
 131
 132       render_water_texture( cam_new );
 133       fb_use( NULL );
 134       glEnable( GL_STENCIL_TEST );
 135
 136       render_water_surface( projection, cam_new );
 137
 138       glStencilMask( 0xFF );
 139       glStencilFunc( GL_ALWAYS, 1, 0xFF );
 140       glDisable( GL_STENCIL_TEST );
 141    }
 142
 143    return 1;
 144 }
 145
 146 VG_STATIC int gate_intersect( teleport_gate *gate, v3f pos, v3f last )
 147 {
 148    v4f surface;
 149    m3x3_mulv( gate->to_world, (v3f){0.0f,0.0f,-1.0f}, surface );
 150    surface[3] = v3_dot( surface, gate->co[0] );
 151
 152    v3f v0, c, delta, p0;
 153    v3_sub( pos, last, v0 );
 154    float l = v3_length( v0 );
 155    v3_divs( v0, l, v0 );
 156
 157    v3_muls( surface, surface[3], c );
 158    v3_sub( c, last, delta );
 159
 160    float d = v3_dot(surface, v0);
 161
 162    if( d > 0.00001f )
 163    {
 164       float t = v3_dot(delta, surface) / d;
 165       if( t >= 0.0f && t <= l )
 166       {
 167          v3f local, rel;
 168          v3_muladds( last, v0, t, local );
 169          v3_sub( gate->co[0], local, rel );
 170
 171          v3f vup, vside;
 172          m3x3_mulv( gate->to_world, (v3f){0.0f,1.0f,0.0f}, vup );
 173          m3x3_mulv( gate->to_world, (v3f){1.0f,0.0f,0.0f}, vside );
 174
 175          v2f xy = { v3_dot( rel, vside ), v3_dot( rel, vup ) };
 176
 177          if( fabsf(xy[0]) <= gate->dims[0] && fabsf(xy[1]) <= gate->dims[1] )
 178          {
 179             return 1;
 180          }
 181       }
 182    }
 183
 184    return 0;
 185 }
 186
 187 #endif /* WORLD_GATE_H */