source/effects/sky.h

   1 #ifndef MSP_GL_SKY_H_
   2 #define MSP_GL_SKY_H_
   3
   4 #include "effect.h"
   5 #include "programdata.h"
   6 #include "rendertarget.h"
   7
   8 namespace Msp {
   9 namespace GL {
  10
  11 class DirectionalLight;
  12 class Mesh;
  13 class Program;
  14
  15 /**
  16 Renders a procedurally generated sky at the background.  Based on the paper
  17 "A Scalable and Production Ready Sky and Atmosphere Rendering Technique" by
  18 Sébastien Hillaire (https://sebh.github.io/publications/egsr2020.pdf).
  19 */
  20 class Sky: public Effect
  21 {
  22 public:
  23         struct Planet
  24         {
  25                 Color rayleigh_scatter;
  26                 Color mie_scatter;
  27                 Color mie_absorb;
  28                 Color ozone_absorb;
  29                 float rayleigh_density_decay;
  30                 float mie_density_decay;
  31                 float ozone_band_center;
  32                 float ozone_band_extent;
  33                 float atmosphere_thickness;
  34                 float planet_radius;
  35                 Color ground_albedo;
  36
  37                 Planet();
  38
  39                 static Planet earth();
  40         };
  41
  42         struct Template: Effect::Template
  43         {
  44                 class Loader: public DataFile::DerivedObjectLoader<Template, Effect::Template::Loader>
  45                 {
  46                 private:
  47                         static ActionMap shared_actions;
  48
  49                 public:
  50                         Loader(Template &, Collection &);
  51                 private:
  52                         virtual void init_actions();
  53                 };
  54
  55                 DirectionalLight *sun = 0;
  56
  57                 virtual Sky *create(const std::map<std::string, Renderable *> &) const;
  58         };
  59
  60 private:
  61         Planet planet;
  62         DirectionalLight &sun;
  63         RenderTarget transmittance_lookup;
  64         const Program &transmittance_shprog;
  65         bool transmittance_lookup_dirty;
  66         RenderTarget distant;
  67         const Program &distant_shprog;
  68         const Mesh &fullscreen_mesh;
  69         const Program &backdrop_shprog;
  70         const Sampler &sampler;
  71         const Sampler &wrap_sampler;
  72         mutable ProgramData shdata;
  73         float view_height;
  74         bool rendered;
  75
  76 public:
  77         Sky(Renderable &, DirectionalLight &);
  78
  79         void set_planet(const Planet &);
  80         void set_view_height(float);
  81
  82         Color get_transmittance(const Vector3 &);
  83
  84         virtual void setup_frame(Renderer &);
  85         virtual void finish_frame();
  86         virtual void render(Renderer &, Tag = Tag()) const;
  87
  88         virtual void set_debug_name(const std::string &);
  89 };
  90
  91 } // namespace GL
  92 } // namespace Msp
  93
  94 #endif