source/effects/ambientocclusion.cpp

   1 #include <algorithm>
   2 #include "ambientocclusion.h"
   3 #include "blend.h"
   4 #include "camera.h"
   5 #include "renderer.h"
   6 #include "resources.h"
   7 #include "shader.h"
   8 #include "tests.h"
   9
  10 using namespace std;
  11
  12 namespace Msp {
  13 namespace GL {
  14
  15 AmbientOcclusion::AmbientOcclusion(unsigned w, unsigned h, float):
  16         occlude_target(w, h, (RENDER_COLOR,R8)),
  17         occlude_shader(Resources::get_global().get<Program>("_ambientocclusion_occlude.glsl.shader")),
  18         combine_shader(Resources::get_global().get<Program>("_ambientocclusion_combine.glsl.shader")),
  19         quad(Resources::get_global().get<Mesh>("_fullscreen_quad.mesh")),
  20         linear_sampler(Resources::get_global().get<Sampler>("_linear_clamp.samp")),
  21         nearest_sampler(Resources::get_global().get<Sampler>("_nearest_clamp.samp"))
  22 {
  23         unsigned seed = 1;
  24         rotate_lookup.storage(RGBA8, 4, 4, 1);
  25         unsigned char data[64];
  26         for(unsigned i=0; i<16; ++i)
  27         {
  28                 Geometry::Angle<float> a = Geometry::Angle<float>::from_turns(random(seed));
  29                 unsigned char c = (cos(a)*0.5f+0.5f)*255;
  30                 unsigned char s = (sin(a)*0.5f+0.5f)*255;
  31                 data[i*4  ] = c;
  32                 data[i*4+1] = s;
  33                 data[i*4+2] = 255-s;
  34                 data[i*4+3] = ((i+i/4)%2)*255;
  35         }
  36         rotate_lookup.image(0, data);
  37
  38         set_n_samples(16);
  39         set_occlusion_radius(0.5f);
  40         set_darkness(1.0f);
  41         set_edge_depth_threshold(0.1f);
  42 }
  43
  44 float AmbientOcclusion::random(unsigned &seed)
  45 {
  46         static const unsigned modulus = (1U<<31)-1;
  47         seed = (static_cast<UInt64>(seed)*48271)%modulus;  // minstd
  48         return static_cast<float>(seed)/(modulus-1);
  49 }
  50
  51 void AmbientOcclusion::set_n_samples(unsigned n)
  52 {
  53         if(n<1 || n>32)
  54                 throw out_of_range("AmbientOcclusion::set_n_samples");
  55
  56         unsigned seed = 1;
  57         float radius_divisor = (n-1)*(n-1);
  58         Vector3 sample_points[32];
  59         for(unsigned i=0; i<n; ++i)
  60         {
  61                 Vector3 v(random(seed)-0.5f, random(seed)-0.5f, random(seed)-0.5f);
  62                 sample_points[i] = normalize(v)*(0.1f+0.9f*i*i/radius_divisor);
  63         }
  64         shdata.uniform3_array("sample_points", n, &sample_points[0].x);
  65         shdata.uniform("n_samples", static_cast<int>(n));
  66 }
  67
  68 void AmbientOcclusion::set_occlusion_radius(float r)
  69 {
  70         shdata.uniform("occlusion_radius", r);
  71 }
  72
  73 void AmbientOcclusion::set_darkness(float darkness)
  74 {
  75         shdata.uniform("darkness", darkness);
  76 }
  77
  78 void AmbientOcclusion::set_edge_depth_threshold(float edt)
  79 {
  80         shdata.uniform("edge_depth_threshold", edt);
  81 }
  82
  83 void AmbientOcclusion::render(Renderer &renderer, const Texture2D &color, const Texture2D &depth)
  84 {
  85         Renderer::Push push(renderer);
  86         renderer.set_texture("source", &color, &nearest_sampler);
  87         renderer.set_texture("depth", &depth, &nearest_sampler);
  88         renderer.set_texture("occlusion", &occlude_target.get_target_texture(RENDER_COLOR), &linear_sampler);
  89         renderer.set_texture("rotate", &rotate_lookup, &nearest_sampler);
  90         renderer.set_shader_program(&occlude_shader, &shdata);
  91
  92         {
  93                 BindRestore bind_fbo(occlude_target.get_framebuffer());
  94                 quad.draw(renderer);
  95         }
  96
  97         renderer.set_shader_program(&combine_shader);
  98         quad.draw(renderer);
  99 }
 100
 101
 102 AmbientOcclusion::Template::Template():
 103         n_samples(16),
 104         occlusion_radius(0.5f),
 105         darkness(1.0f),
 106         edge_depth_threshold(0.1f)
 107 { }
 108
 109 AmbientOcclusion *AmbientOcclusion::Template::create(unsigned width, unsigned height) const
 110 {
 111         RefPtr<AmbientOcclusion> ao = new AmbientOcclusion(width/size_divisor, height/size_divisor);
 112         ao->set_n_samples(n_samples);
 113         ao->set_occlusion_radius(occlusion_radius);
 114         ao->set_darkness(darkness);
 115         ao->set_edge_depth_threshold(edge_depth_threshold);
 116         return ao.release();
 117 }
 118
 119
 120 AmbientOcclusion::Template::Loader::Loader(Template &t):
 121         DataFile::DerivedObjectLoader<Template, PostProcessor::Template::Loader>(t)
 122 {
 123         add("darkness", &Template::darkness);
 124         add("edge_depth_threshold", &Template::edge_depth_threshold);
 125         add("occlusion_radius", &Template::occlusion_radius);
 126         add("samples", &Template::n_samples);
 127 }
 128
 129 } // namespace GL
 130 } // namespace Msp