world_water.h

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