source/effects/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 "resources.h"
   8 #include "shader.h"
   9 #include "tests.h"
  10 #include "texunit.h"
  11
  12 using namespace std;
  13
  14 namespace Msp {
  15 namespace GL {
  16
  17 Bloom::Bloom(Resources &resources, unsigned w, unsigned h):
  18         blur_shader(resources.get<Program>("_bloom_blur.glsl.shader")),
  19         combine_shader(resources.get<Program>("_bloom_combine.glsl.shader")),
  20         quad(resources.get<Mesh>("_fullscreen_quad.mesh")),
  21         nearest_sampler(resources.get<Sampler>("_nearest_clamp.samp")),
  22         linear_sampler(resources.get<Sampler>("_linear_clamp.samp"))
  23 {
  24         blur_shdata[0].uniform("delta", 1.0f/w, 0.0f);
  25         blur_shdata[1].uniform("delta", 0.0f, 1.0f/h);
  26
  27         for(unsigned i=0; i<2; ++i)
  28                 target[i] = new RenderTarget(w, h, (RENDER_COLOR,RGB16F));
  29
  30         set_radius(2.0f);
  31         set_strength(0.2f);
  32 }
  33
  34 Bloom::~Bloom()
  35 {
  36         for(unsigned i=0; i<2; ++i)
  37                 delete target[i];
  38 }
  39
  40 void Bloom::set_radius(float r)
  41 {
  42         if(r<=0.0f)
  43                 throw invalid_argument("Bloom::set_radius");
  44
  45         int size = min(static_cast<int>(r*3.0f), 9);
  46         common_shdata.uniform("size", size);
  47
  48         vector<float> factors(size*2+1);
  49         float sum = 0.0f;
  50         r = 2*r*r;
  51         for(int i=-size; i<=size; ++i)
  52                 sum += (factors[size+i] = exp(-i*i/r));
  53         for(int i=0; i<=size*2; ++i)
  54                 factors[i] /= sum;
  55
  56         common_shdata.uniform1_array("factors", size*2+1, &factors.front());
  57 }
  58
  59 void Bloom::set_strength(float s)
  60 {
  61         if(s<0.0f || s>1.0f)
  62                 throw invalid_argument("Bloom::set_strength");
  63         common_shdata.uniform("strength", s);
  64 }
  65
  66 void Bloom::render(Renderer &renderer, const Texture2D &src, const Texture2D &)
  67 {
  68         Renderer::Push push(renderer);
  69         renderer.set_shader_program(&blur_shader, &common_shdata);
  70         for(unsigned i=0; i<2; ++i)
  71         {
  72                 BindRestore bind_fbo(target[i]->get_framebuffer());
  73                 Renderer::Push push2(renderer);
  74                 renderer.set_texture("source", (i ? &target[0]->get_target_texture(RENDER_COLOR) : &src), &nearest_sampler);
  75                 renderer.add_shader_data(blur_shdata[i]);
  76                 quad.draw(renderer);
  77         }
  78
  79         renderer.set_texture("source", &src, &nearest_sampler);
  80         renderer.set_texture("blurred", &target[1]->get_target_texture(RENDER_COLOR), &linear_sampler);
  81         renderer.set_shader_program(&combine_shader);
  82         quad.draw(renderer);
  83 }
  84
  85
  86 Bloom::Template::Template():
  87         radius(2.0f),
  88         strength(0.2f)
  89 { }
  90
  91 Bloom *Bloom::Template::create(Resources &res, unsigned width, unsigned height) const
  92 {
  93         RefPtr<Bloom> bloom = new Bloom(res, width/size_divisor, height/size_divisor);
  94         bloom->set_radius(radius);
  95         bloom->set_strength(strength);
  96         return bloom.release();
  97 }
  98
  99
 100 Bloom::Template::Loader::Loader(Template &t):
 101         DataFile::DerivedObjectLoader<Template, PostProcessor::Template::Loader>(t)
 102 {
 103         add("strength", &Template::strength);
 104         add("radius", &Template::radius);
 105 }
 106
 107 } // namespace GL
 108 } // namespace Msp