source/bloom.cpp

   1 #include <cmath>
   2 #include <msp/strings/format.h>
   3 #include "blend.h"
   4 #include "bloom.h"
   5 #include "misc.h"
   6 #include "renderer.h"
   7 #include "shader.h"
   8 #include "tests.h"
   9 #include "texunit.h"
  10
  11 using namespace std;
  12
  13 namespace Msp {
  14 namespace GL {
  15
  16 Bloom::Bloom(unsigned w, unsigned h):
  17         blur_shader("bloom_blur.glsl"),
  18         combine_shader("bloom_combine.glsl"),
  19         quad(get_fullscreen_quad())
  20 {
  21         blur_shdata[0].uniform("delta", 1.0f/w, 0.0f);
  22         blur_shdata[1].uniform("delta", 0.0f, 1.0f/h);
  23
  24         blur_shdata_common.uniform("source", 0);
  25         for(unsigned i=0; i<2; ++i)
  26         {
  27                 tex[i].set_min_filter(NEAREST);
  28                 tex[i].set_wrap(CLAMP_TO_EDGE);
  29                 tex[i].storage(RGB16F, w, h);
  30                 fbo[i].attach(COLOR_ATTACHMENT0, tex[i], 0);
  31                 fbo[i].require_complete();
  32         }
  33
  34         combine_shdata.uniform("source", 1);
  35         combine_shdata.uniform("blurred", 0);
  36
  37         combine_texturing.attach(0, tex[1]);
  38
  39         set_radius(2.0f);
  40         set_strength(0.2f);
  41 }
  42
  43 void Bloom::set_radius(float r)
  44 {
  45         if(r<=0.0f)
  46                 throw invalid_argument("Bloom::set_radius");
  47
  48         int size = min(static_cast<int>(r*3.0f), 9);
  49         blur_shdata_common.uniform("size", size);
  50
  51         vector<float> factors(size*2+1);
  52         float sum = 0.0f;
  53         r = 2*r*r;
  54         for(int i=-size; i<=size; ++i)
  55                 sum += (factors[size+i] = exp(-i*i/r));
  56         for(int i=0; i<=size*2; ++i)
  57                 factors[i] /= sum;
  58
  59         blur_shdata_common.uniform1_array("factors", size*2+1, &factors.front());
  60 }
  61
  62 void Bloom::set_strength(float s)
  63 {
  64         if(s<0.0f || s>1.0f)
  65                 throw invalid_argument("Bloom::set_strength");
  66         combine_shdata.uniform("strength", s);
  67 }
  68
  69 void Bloom::render(Renderer &renderer, const Texture2D &src, const Texture2D &)
  70 {
  71         {
  72                 Renderer::Push push(renderer);
  73                 renderer.set_shader_program(&blur_shader, &blur_shdata_common);
  74                 for(unsigned i=0; i<2; ++i)
  75                 {
  76                         BindRestore bind_fbo(fbo[i]);
  77                         Renderer::Push push2(renderer);
  78                         renderer.set_texture(i ? &tex[0] : &src);
  79                         renderer.add_shader_data(blur_shdata[i]);
  80                         quad.draw(renderer);
  81                 }
  82         }
  83
  84         Renderer::Push push(renderer);
  85         combine_texturing.attach(1, src);
  86         renderer.set_texturing(&combine_texturing);
  87         renderer.set_shader_program(&combine_shader, &combine_shdata);
  88         quad.draw(renderer);
  89 }
  90
  91 } // namespace GL
  92 } // namespace Msp