world_water.h

   1 /*
   2  * Copyright (C) 2021-2022 Mt.ZERO Software, Harry Godden - All Rights Reserved
   3  */
   4
   5 #ifndef WATER_H
   6 #define WATER_H
   7
   8 #include "world.h"
   9 #include "render.h"
  10 #include "shaders/water.h"
  11 #include "scene.h"
  12
  13 vg_tex2d tex_water_surf = { .path = "textures/water_surf.qoi" };
  14
  15 static struct
  16 {
  17    struct framebuffer fbreflect, fbdepth;
  18    glmesh mdl;
  19
  20    boxf depthbounds;
  21    int depth_computed;
  22
  23    float height;
  24    int enabled;
  25    v4f plane;
  26 }
  27 wrender =
  28 {
  29    .fbreflect = { .format = GL_RGB,  .div = 3 },
  30    .fbdepth   = { .format = GL_RGBA, .div = 4 }
  31 };
  32
  33 static void world_water_init(void)
  34 {
  35    vg_info( "world_water_init\n" );
  36    shader_water_register();
  37
  38    vg_acquire_thread_sync();
  39    {
  40       fb_init( &wrender.fbreflect );
  41       fb_init( &wrender.fbdepth );
  42
  43       vg_tex2d_init( (vg_tex2d *[]){&tex_water_surf}, 1 );
  44       vg_success( "done\n" );
  45    }
  46    vg_release_thread_sync();
  47 }
  48
  49 static void world_water_free(void *_)
  50 {
  51    vg_tex2d_free( (vg_tex2d *[]){&tex_water_surf}, 1 );
  52    fb_free( &wrender.fbreflect );
  53    fb_free( &wrender.fbdepth );
  54 }
  55
  56 static void water_fb_resize(void)
  57 {
  58    if( !wrender.enabled )
  59       return;
  60
  61    fb_resize( &wrender.fbreflect );
  62    fb_resize( &wrender.fbdepth );
  63 }
  64
  65 static void water_set_surface( glmesh *surf, float height )
  66 {
  67    wrender.mdl = *surf;
  68    wrender.height = height;
  69    wrender.enabled = 1;
  70
  71    v4_copy( (v4f){ 0.0f, 1.0f, 0.0f, height }, wrender.plane );
  72 }
  73
  74 static void render_water_texture( m4x3f camera )
  75 {
  76    if( !wrender.enabled )
  77       return;
  78
  79    /* Draw reflection buffa */
  80    fb_use( &wrender.fbreflect );
  81    glClear( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT );
  82
  83    m4x3f new_cam, inverse;
  84    v3_copy( camera[3], new_cam[3] );
  85    new_cam[3][1] -= 2.0f * (camera[3][1] - wrender.height);
  86
  87    m3x3f flip;
  88    m3x3_identity( flip );
  89    flip[1][1] = -1.0f;
  90    m3x3_mul( flip, camera, new_cam );
  91
  92
  93    v3f p0;
  94    m3x3_mulv( new_cam, (v3f){0.0f,0.0f,-1.0f}, p0 );
  95    v3_add( new_cam[3], p0, p0 );
  96    vg_line( new_cam[3], p0, 0xffffffff );
  97
  98    m4x4f view;
  99    vg_line_pt3( new_cam[3], 0.3f, 0xff00ffff );
 100
 101    m4x3_invert_affine( new_cam, inverse );
 102    m4x3_expand( inverse, view );
 103
 104    v4f clippa = { 0.0f, 1.0f, 0.0f, wrender.height-0.1f };
 105    m4x3_mulp( inverse, clippa, clippa );
 106    clippa[3] *= -1.0f;
 107
 108    m4x4f projection;
 109    m4x4_projection( projection,
 110          gpipeline.fov,
 111          (float)vg_window_x / (float)vg_window_y,
 112          0.1f, 900.0f );
 113    plane_clip_projection( projection, clippa );
 114    m4x4_mul( projection, view, projection );
 115
 116    glCullFace( GL_FRONT );
 117    render_world( projection, new_cam );
 118    glCullFace( GL_BACK );
 119
 120
 121    /* Draw beneath texture */
 122    fb_use( &wrender.fbdepth );
 123    glClear( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT );
 124
 125    m4x3_invert_affine( camera, inverse );
 126    m4x3_expand( inverse, view );
 127
 128    float bias = -(camera[3][1]-wrender.height)*0.1f;
 129    v4f clippb = { 0.0f, -1.0f, 0.0f, -(wrender.height) + bias };
 130    m4x3_mulp( inverse, clippb, clippb );
 131    clippb[3] *= -1.0f;
 132
 133    m4x4_projection( projection,
 134          gpipeline.fov,
 135          (float)vg_window_x / (float)vg_window_y,
 136          0.1f, 900.0f );
 137
 138    plane_clip_projection( projection, clippb );
 139    m4x4_mul( projection, view, projection );
 140    render_world_depth( projection, camera );
 141
 142    glViewport( 0, 0, vg_window_x, vg_window_y );
 143 }
 144
 145 static void render_water_surface( m4x4f pv, m4x3f camera )
 146 {
 147    if( !wrender.enabled )
 148       return;
 149
 150    /* Draw surface */
 151    shader_water_use();
 152
 153    fb_bindtex( &wrender.fbreflect, 0 );
 154    shader_water_uTexMain( 0 );
 155
 156    vg_tex2d_bind( &tex_water_surf, 1 );
 157    shader_water_uTexDudv( 1 );
 158    shader_water_uInvRes( (v2f){
 159          1.0f / (float)vg_window_x,
 160          1.0f / (float)vg_window_y });
 161
 162    shader_link_standard_ub( _shader_water.id, 2 );
 163
 164    fb_bindtex( &wrender.fbdepth, 3 );
 165    shader_water_uTexBack( 3 );
 166    shader_water_uTime( vg_time );
 167    shader_water_uCamera( camera[3] );
 168    shader_water_uSurfaceY( wrender.height );
 169
 170    shader_water_uPv( pv );
 171
 172    m4x3f full;
 173    m4x3_identity( full );
 174    full[3][1] = wrender.height;
 175
 176    shader_water_uMdl( full );
 177
 178    glEnable(GL_BLEND);
 179    glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
 180    glBlendEquation(GL_FUNC_ADD);
 181
 182    mesh_bind( &wrender.mdl );
 183    mesh_draw( &wrender.mdl );
 184
 185    glDisable(GL_BLEND);
 186 }
 187
 188 #endif /* WATER_H */