source/effects/shadowmap.cpp

   1 #include <msp/strings/format.h>
   2 #include "directionallight.h"
   3 #include "error.h"
   4 #include "lighting.h"
   5 #include "renderer.h"
   6 #include "resources.h"
   7 #include "shadowmap.h"
   8
   9 using namespace std;
  10
  11 namespace Msp {
  12 namespace GL {
  13
  14 ShadowMap::ShadowMap(unsigned w, unsigned h, Renderable &r, const Lighting *l, Renderable &c):
  15         Effect(r),
  16         width(w),
  17         height(h),
  18         lighting(l),
  19         shadow_caster(c),
  20         sampler(Resources::get_global().get<Sampler>("_linear_clamp_shadow.samp"))
  21 {
  22         depth_buf.storage(DEPTH_COMPONENT32F, width, height, 1);
  23         fbo.set_format((DEPTH_ATTACHMENT,DEPTH_COMPONENT32F));
  24         fbo.attach(DEPTH_ATTACHMENT, depth_buf, 0);
  25
  26         set_darkness(1.0f);
  27         for(unsigned i=0; i<4; ++i)
  28         {
  29                 string base = format("shadows[%d]", i);
  30                 shdata.uniform(base+".enabled", 0);
  31                 shdata.uniform(base+".darkness", 1.0f);
  32                 shdata.uniform(base+".shd_world_matrix", Matrix());
  33                 shdata.uniform(base+".region", Vector4(0.0f, 0.0f, 1.0f, 1.0f));
  34         }
  35 }
  36
  37 ShadowMap::ShadowMap(unsigned s, Renderable &r, const DirectionalLight &l, Renderable &c):
  38         ShadowMap(s, s, r, 0, c)
  39 {
  40         add_light(l, s);
  41 }
  42
  43 ShadowMap::ShadowMap(unsigned w, unsigned h, Renderable &r, const Lighting &l, Renderable &c):
  44         ShadowMap(w, h, r, &l, c)
  45 { }
  46
  47 void ShadowMap::add_light(const DirectionalLight &light, unsigned s)
  48 {
  49         if(!lighting && !lights.empty())
  50                 throw invalid_operation("ShadowMap::add_light");
  51
  52         int index = (lighting ? lighting->find_light_index(light) : 0);
  53         if(index<0)
  54                 throw invalid_argument("ShadowMap::add_light");
  55
  56         Rect region(0, 0, s, s);
  57         while(1)
  58         {
  59                 int next_bottom = height;
  60                 int next_left = region.left;
  61
  62                 int top = region.bottom+region.height;
  63                 int right = region.left+region.width;
  64                 for(const ShadowedLight &l: lights)
  65                 {
  66                         int l_top = l.region.bottom+l.region.height;
  67                         int l_right = l.region.left+l.region.width;
  68                         if(l_top>region.bottom)
  69                                 next_bottom = min(next_bottom, l_top);
  70
  71                         if(top>l.region.bottom && region.bottom<l_top && right>l.region.left && region.left<l_right)
  72                                 next_left = max(next_left, l_right);
  73                 }
  74
  75                 if(next_left==region.left)
  76                         break;
  77                 else if(next_left+region.width>width)
  78                 {
  79                         if(next_bottom+region.height>height)
  80                                 throw invalid_operation("ShadowMap::add_light");
  81                         region.bottom = next_bottom;
  82                         region.left = 0;
  83                 }
  84                 else
  85                         region.left = next_left;
  86         }
  87
  88         lights.emplace_back();
  89         ShadowedLight &sl = lights.back();
  90         sl.light = &light;
  91         sl.index = index;
  92         sl.region = region;
  93
  94         string base = format("shadows[%d]", index);
  95         shdata.uniform(base+".enabled", 1);
  96         shdata.uniform(base+".darkness", darkness);
  97
  98         float xf = static_cast<float>(region.left)/width;
  99         float yf = static_cast<float>(region.bottom)/height;
 100         float wf = static_cast<float>(region.width)/width;
 101         float hf = static_cast<float>(region.height)/height;
 102         shdata.uniform(base+".region", Vector4(xf, yf, wf, hf));
 103
 104 #ifdef DEBUG
 105         if(!debug_name.empty())
 106                 sl.shadow_camera.set_debug_name(format("%s/light%d.camera", debug_name, lights.size()-1));
 107 #endif
 108 }
 109
 110 void ShadowMap::set_target(const Vector3 &t, float r)
 111 {
 112         target = t;
 113         radius = r;
 114 }
 115
 116 void ShadowMap::set_darkness(float d)
 117 {
 118         if(d<0.0f || d>1.0f)
 119                 throw invalid_argument("ShadowMap::set_darkness");
 120
 121         darkness = d;
 122         for(const ShadowedLight &l: lights)
 123                 shdata.uniform(format("shadows[%d].darkness", l.index), d);
 124 }
 125
 126 void ShadowMap::set_depth_bias(float b)
 127 {
 128         if(b<0.0f)
 129                 throw invalid_argument("ShadowMap::set_depth_bias");
 130
 131         depth_bias = b;
 132 }
 133
 134 void ShadowMap::setup_frame(Renderer &renderer)
 135 {
 136         if(rendered)
 137                 return;
 138
 139         rendered = true;
 140         renderable.setup_frame(renderer);
 141         shadow_caster.setup_frame(renderer);
 142
 143         for(ShadowedLight &l: lights)
 144         {
 145                 l.shadow_camera.set_object_matrix(*l.light->get_matrix());
 146                 l.shadow_camera.set_position(target);
 147                 // TODO support point and spot lights with a frustum projection.
 148                 // Omnidirectional lights also need a cube shadow map.
 149                 l.shadow_camera.set_orthographic(radius*2, radius*2);
 150                 l.shadow_camera.set_depth_clip(-radius, radius);
 151
 152                 Matrix to_texcoord = Matrix().translate(Vector3(0.5f, 0.5f, 0.5f-depth_bias/l.region.width)).scale(0.5f);
 153                 Matrix shadow_matrix = to_texcoord*l.shadow_camera.get_projection_matrix()*l.shadow_camera.get_view_matrix();
 154
 155                 shdata.uniform(format("shadows[%d].shd_world_matrix", l.index), shadow_matrix);
 156         }
 157
 158         for(ShadowedLight &l: lights)
 159         {
 160                 Renderer::Push push(renderer);
 161                 renderer.set_framebuffer(&fbo);
 162                 renderer.set_viewport(&l.region);
 163                 renderer.set_scissor(&l.region);
 164                 renderer.set_camera(l.shadow_camera);
 165
 166                 renderer.render(shadow_caster);
 167         }
 168 }
 169
 170 void ShadowMap::finish_frame()
 171 {
 172         if(rendered)
 173         {
 174                 rendered = false;
 175                 renderable.finish_frame();
 176         }
 177 }
 178
 179 void ShadowMap::render(Renderer &renderer, Tag tag) const
 180 {
 181         if(!enabled_passes.count(tag))
 182                 return renderer.render(renderable, tag);
 183
 184         Renderer::Push _push_rend(renderer);
 185
 186         renderer.set_texture("shadow_map", &depth_buf, &sampler);
 187         renderer.add_shader_data(shdata);
 188         renderer.render(renderable, tag);
 189 }
 190
 191 void ShadowMap::set_debug_name(const string &name)
 192 {
 193 #ifdef DEBUG
 194         fbo.set_debug_name(name+" [FBO]");
 195         for(unsigned i=0; i<lights.size(); ++i)
 196                 lights[i].shadow_camera.set_debug_name(format("%s/light%d.camera", name, i));
 197         depth_buf.set_debug_name(name+"/depth.tex");
 198         shdata.set_debug_name(name+" [UBO]");
 199 #else
 200         (void)name;
 201 #endif
 202 }
 203
 204 } // namespace GL
 205 } // namespace Msp