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