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(Resources &resources, unsigned w, unsigned h, float):
  16         occlude_target(w, h, (RENDER_COLOR,R8)),
  17         occlude_shader(resources.get<Program>("_ambientocclusion_occlude.glsl.shader")),
  18         combine_shader(resources.get<Program>("_ambientocclusion_combine.glsl.shader")),
  19         quad(resources.get<Mesh>("_fullscreen_quad.mesh")),
  20         linear_sampler(resources.get<Sampler>("_linear_clamp.samp")),
  21         nearest_sampler(resources.get<Sampler>("_nearest_clamp.samp"))
  22 {
  23         texturing.attach(2, occlude_target.get_target_texture(RENDER_COLOR), &linear_sampler);
  24
  25         unsigned seed = 1;
  26         rotate_lookup.storage(RGBA8, 4, 4, 1);
  27         unsigned char data[64];
  28         for(unsigned i=0; i<16; ++i)
  29         {
  30                 Geometry::Angle<float> a = Geometry::Angle<float>::from_turns(random(seed));
  31                 unsigned char c = (cos(a)*0.5f+0.5f)*255;
  32                 unsigned char s = (sin(a)*0.5f+0.5f)*255;
  33                 data[i*4  ] = c;
  34                 data[i*4+1] = s;
  35                 data[i*4+2] = 255-s;
  36                 data[i*4+3] = ((i+i/4)%2)*255;
  37         }
  38         rotate_lookup.image(0, data);
  39
  40         texturing.attach(3, rotate_lookup, &nearest_sampler);
  41
  42         shdata.uniform("source", 0);
  43         shdata.uniform("depth", 1);
  44         shdata.uniform("occlusion", 2);
  45         shdata.uniform("rotate", 3);
  46         shdata.uniform("inverse_projection", Matrix());
  47
  48         set_n_samples(16);
  49         set_occlusion_radius(0.5f);
  50         set_darkness(1.0f);
  51         set_edge_depth_threshold(0.1f);
  52 }
  53
  54 float AmbientOcclusion::random(unsigned &seed)
  55 {
  56         static const unsigned modulus = (1U<<31)-1;
  57         seed = (static_cast<UInt64>(seed)*48271)%modulus;  // minstd
  58         return static_cast<float>(seed)/(modulus-1);
  59 }
  60
  61 void AmbientOcclusion::set_n_samples(unsigned n)
  62 {
  63         if(n<1 || n>32)
  64                 throw out_of_range("AmbientOcclusion::set_n_samples");
  65
  66         unsigned seed = 1;
  67         float radius_divisor = (n-1)*(n-1);
  68         Vector3 sample_points[32];
  69         for(unsigned i=0; i<n; ++i)
  70         {
  71                 Vector3 v(random(seed)-0.5f, random(seed)-0.5f, random(seed)-0.5f);
  72                 sample_points[i] = normalize(v)*(0.1f+0.9f*i*i/radius_divisor);
  73         }
  74         shdata.uniform3_array("sample_points", n, &sample_points[0].x);
  75         shdata.uniform("n_samples", static_cast<int>(n));
  76 }
  77
  78 void AmbientOcclusion::set_occlusion_radius(float r)
  79 {
  80         shdata.uniform("occlusion_radius", r);
  81 }
  82
  83 void AmbientOcclusion::set_darkness(float darkness)
  84 {
  85         shdata.uniform("darkness", darkness);
  86 }
  87
  88 void AmbientOcclusion::set_edge_depth_threshold(float edt)
  89 {
  90         shdata.uniform("edge_depth_threshold", edt);
  91 }
  92
  93 void AmbientOcclusion::render(Renderer &renderer, const Texture2D &color, const Texture2D &depth)
  94 {
  95         texturing.attach(0, color, &nearest_sampler);
  96         texturing.attach(1, depth, &nearest_sampler);
  97
  98         if(renderer.get_camera())
  99                 shdata.uniform("inverse_projection", invert(renderer.get_camera()->get_projection_matrix()));
 100
 101         Renderer::Push push(renderer);
 102         renderer.set_texturing(&texturing);
 103         renderer.set_shader_program(&occlude_shader, &shdata);
 104
 105         {
 106                 BindRestore bind_fbo(occlude_target.get_framebuffer());
 107                 quad.draw(renderer);
 108         }
 109
 110         renderer.set_shader_program(&combine_shader);
 111         quad.draw(renderer);
 112 }
 113
 114
 115 AmbientOcclusion::Template::Template():
 116         n_samples(16),
 117         occlusion_radius(0.5f),
 118         darkness(1.0f),
 119         edge_depth_threshold(0.1f)
 120 { }
 121
 122 AmbientOcclusion *AmbientOcclusion::Template::create(Resources &res, unsigned width, unsigned height) const
 123 {
 124         RefPtr<AmbientOcclusion> ao = new AmbientOcclusion(res, width/size_divisor, height/size_divisor);
 125         ao->set_n_samples(n_samples);
 126         ao->set_occlusion_radius(occlusion_radius);
 127         ao->set_darkness(darkness);
 128         ao->set_edge_depth_threshold(edge_depth_threshold);
 129         return ao.release();
 130 }
 131
 132
 133 AmbientOcclusion::Template::Loader::Loader(Template &t):
 134         DataFile::DerivedObjectLoader<Template, PostProcessor::Template::Loader>(t)
 135 {
 136         add("darkness", &Template::darkness);
 137         add("edge_depth_threshold", &Template::edge_depth_threshold);
 138         add("occlusion_radius", &Template::occlusion_radius);
 139         add("samples", &Template::n_samples);
 140 }
 141
 142 } // namespace GL
 143 } // namespace Msp