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 "shader.h"
   7 #include "tests.h"
   8
   9 using namespace std;
  10
  11 namespace Msp {
  12 namespace GL {
  13
  14 AmbientOcclusion::AmbientOcclusion(unsigned w, unsigned h, float):
  15         occlude_target(w, h, (RENDER_COLOR,R8)),
  16         occlude_shader("ambientocclusion_occlude.glsl"),
  17         combine_shader("ambientocclusion_combine.glsl"),
  18         quad(get_fullscreen_quad()),
  19         linear_sampler(get_linear_sampler()),
  20         nearest_sampler(get_nearest_sampler())
  21 {
  22         texturing.attach(2, occlude_target.get_target_texture(RENDER_COLOR), linear_sampler.get());
  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         texturing.attach(3, rotate_lookup, nearest_sampler.get());
  40
  41         shdata.uniform("source", 0);
  42         shdata.uniform("depth", 1);
  43         shdata.uniform("occlusion", 2);
  44         shdata.uniform("rotate", 3);
  45         shdata.uniform("inverse_projection", Matrix());
  46
  47         set_n_samples(16);
  48         set_occlusion_radius(0.5f);
  49         set_darkness(1.0f);
  50         set_edge_depth_threshold(0.1f);
  51 }
  52
  53 float AmbientOcclusion::random(unsigned &seed)
  54 {
  55         static const unsigned modulus = (1U<<31)-1;
  56         seed = (static_cast<UInt64>(seed)*48271)%modulus;  // minstd
  57         return static_cast<float>(seed)/(modulus-1);
  58 }
  59
  60 void AmbientOcclusion::set_n_samples(unsigned n)
  61 {
  62         if(n<1 || n>32)
  63                 throw out_of_range("AmbientOcclusion::set_n_samples");
  64
  65         unsigned seed = 1;
  66         float radius_divisor = (n-1)*(n-1);
  67         Vector3 sample_points[32];
  68         for(unsigned i=0; i<n; ++i)
  69         {
  70                 Vector3 v(random(seed)-0.5f, random(seed)-0.5f, random(seed)-0.5f);
  71                 sample_points[i] = normalize(v)*(0.1f+0.9f*i*i/radius_divisor);
  72         }
  73         shdata.uniform3_array("sample_points", n, &sample_points[0].x);
  74         shdata.uniform("n_samples", static_cast<int>(n));
  75 }
  76
  77 void AmbientOcclusion::set_occlusion_radius(float r)
  78 {
  79         shdata.uniform("occlusion_radius", r);
  80 }
  81
  82 void AmbientOcclusion::set_darkness(float darkness)
  83 {
  84         shdata.uniform("darkness", darkness);
  85 }
  86
  87 void AmbientOcclusion::set_edge_depth_threshold(float edt)
  88 {
  89         shdata.uniform("edge_depth_threshold", edt);
  90 }
  91
  92 void AmbientOcclusion::render(Renderer &renderer, const Texture2D &color, const Texture2D &depth)
  93 {
  94         texturing.attach(0, color, nearest_sampler.get());
  95         texturing.attach(1, depth, nearest_sampler.get());
  96
  97         if(renderer.get_camera())
  98                 shdata.uniform("inverse_projection", invert(renderer.get_camera()->get_projection_matrix()));
  99
 100         Renderer::Push push(renderer);
 101         renderer.set_texturing(&texturing);
 102         renderer.set_shader_program(&occlude_shader, &shdata);
 103
 104         {
 105                 BindRestore bind_fbo(occlude_target.get_framebuffer());
 106                 quad->draw(renderer);
 107         }
 108
 109         renderer.set_shader_program(&combine_shader);
 110         quad->draw(renderer);
 111 }
 112
 113
 114 AmbientOcclusion::Template::Template():
 115         n_samples(16),
 116         occlusion_radius(0.5f),
 117         darkness(1.0f),
 118         edge_depth_threshold(0.1f)
 119 { }
 120
 121 AmbientOcclusion *AmbientOcclusion::Template::create(unsigned width, unsigned height) const
 122 {
 123         RefPtr<AmbientOcclusion> ao = new AmbientOcclusion(width/size_divisor, height/size_divisor);
 124         ao->set_n_samples(n_samples);
 125         ao->set_occlusion_radius(occlusion_radius);
 126         ao->set_darkness(darkness);
 127         ao->set_edge_depth_threshold(edge_depth_threshold);
 128         return ao.release();
 129 }
 130
 131
 132 AmbientOcclusion::Template::Loader::Loader(Template &t):
 133         DataFile::DerivedObjectLoader<Template, PostProcessor::Template::Loader>(t)
 134 {
 135         add("darkness", &Template::darkness);
 136         add("edge_depth_threshold", &Template::edge_depth_threshold);
 137         add("occlusion_radius", &Template::occlusion_radius);
 138         add("samples", &Template::n_samples);
 139 }
 140
 141 } // namespace GL
 142 } // namespace Msp