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):
  15         Effect(r),
  16         width(w),
  17         height(h),
  18         lighting(l),
  19         sampler(Resources::get_global().get<Sampler>("_linear_clamp_shadow.samp"))
  20 {
  21         depth_buf.storage(DEPTH_COMPONENT32F, width, height, 1);
  22         fbo.set_format((DEPTH_ATTACHMENT,DEPTH_COMPONENT32F));
  23         fbo.attach(DEPTH_ATTACHMENT, depth_buf, 0);
  24
  25         set_darkness(1.0f);
  26         for(unsigned i=0; i<4; ++i)
  27         {
  28                 string base = format("shadows[%d]", i);
  29                 shdata.uniform(base+".enabled", 0);
  30                 shdata.uniform(base+".darkness", 1.0f);
  31                 shdata.uniform(base+".shd_world_matrix", Matrix());
  32                 shdata.uniform(base+".region", Vector4(0.0f, 0.0f, 1.0f, 1.0f));
  33         }
  34 }
  35
  36 ShadowMap::ShadowMap(unsigned s, Renderable &r, const DirectionalLight &l, Renderable &c):
  37         ShadowMap(s, s, r, 0)
  38 {
  39         add_light(l, s, c);
  40 }
  41
  42 ShadowMap::ShadowMap(unsigned w, unsigned h, Renderable &r, const Lighting &l):
  43         ShadowMap(w, h, r, &l)
  44 { }
  45
  46 void ShadowMap::add_light(const DirectionalLight &light, unsigned s, Renderable &c)
  47 {
  48         if(!lighting && !lights.empty())
  49                 throw invalid_operation("ShadowMap::add_light");
  50
  51         int index = (lighting ? lighting->find_light_index(light) : 0);
  52         if(index<0)
  53                 throw invalid_argument("ShadowMap::add_light");
  54
  55         Rect region(0, 0, s, s);
  56         while(1)
  57         {
  58                 int next_bottom = height;
  59                 int next_left = region.left;
  60
  61                 int top = region.bottom+region.height;
  62                 int right = region.left+region.width;
  63                 for(const ShadowedLight &l: lights)
  64                 {
  65                         int l_top = l.region.bottom+l.region.height;
  66                         int l_right = l.region.left+l.region.width;
  67                         if(l_top>region.bottom)
  68                                 next_bottom = min(next_bottom, l_top);
  69
  70                         if(top>l.region.bottom && region.bottom<l_top && right>l.region.left && region.left<l_right)
  71                                 next_left = max(next_left, l_right);
  72                 }
  73
  74                 if(next_left==region.left)
  75                         break;
  76                 else if(next_left+region.width>width)
  77                 {
  78                         if(next_bottom+region.height>height)
  79                                 throw invalid_operation("ShadowMap::add_light");
  80                         region.bottom = next_bottom;
  81                         region.left = 0;
  82                 }
  83                 else
  84                         region.left = next_left;
  85         }
  86
  87         lights.emplace_back();
  88         ShadowedLight &sl = lights.back();
  89         sl.light = &light;
  90         sl.index = index;
  91         sl.region = region;
  92         sl.shadow_caster = &c;
  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         for(const ShadowedLight &l: lights)
 142                 l.shadow_caster->setup_frame(renderer);
 143
 144         for(ShadowedLight &l: lights)
 145         {
 146                 l.shadow_camera.set_object_matrix(*l.light->get_matrix());
 147                 l.shadow_camera.set_position(target);
 148                 // TODO support point and spot lights with a frustum projection.
 149                 // Omnidirectional lights also need a cube shadow map.
 150                 l.shadow_camera.set_orthographic(radius*2, radius*2);
 151                 l.shadow_camera.set_depth_clip(-radius, radius);
 152
 153                 Matrix to_texcoord = Matrix().translate(Vector3(0.5f, 0.5f, 0.5f-depth_bias/l.region.width)).scale(0.5f);
 154                 Matrix shadow_matrix = to_texcoord*l.shadow_camera.get_projection_matrix()*l.shadow_camera.get_view_matrix();
 155
 156                 shdata.uniform(format("shadows[%d].shd_world_matrix", l.index), shadow_matrix);
 157         }
 158
 159         for(ShadowedLight &l: lights)
 160         {
 161                 Renderer::Push push(renderer);
 162                 renderer.set_framebuffer(&fbo);
 163                 renderer.set_viewport(&l.region);
 164                 renderer.set_scissor(&l.region);
 165                 renderer.set_camera(l.shadow_camera);
 166
 167                 renderer.render(*light.shadow_caster);
 168         }
 169 }
 170
 171 void ShadowMap::finish_frame()
 172 {
 173         if(rendered)
 174         {
 175                 rendered = false;
 176                 renderable.finish_frame();
 177         }
 178 }
 179
 180 void ShadowMap::render(Renderer &renderer, Tag tag) const
 181 {
 182         if(!enabled_passes.count(tag))
 183                 return renderer.render(renderable, tag);
 184
 185         Renderer::Push _push_rend(renderer);
 186
 187         renderer.set_texture("shadow_map", &depth_buf, &sampler);
 188         renderer.add_shader_data(shdata);
 189         renderer.render(renderable, tag);
 190 }
 191
 192 void ShadowMap::set_debug_name(const string &name)
 193 {
 194 #ifdef DEBUG
 195         fbo.set_debug_name(name+" [FBO]");
 196         for(unsigned i=0; i<lights.size(); ++i)
 197                 lights[i].shadow_camera.set_debug_name(format("%s/light%d.camera", name, i));
 198         depth_buf.set_debug_name(name+"/depth.tex");
 199         shdata.set_debug_name(name+" [UBO]");
 200 #else
 201         (void)name;
 202 #endif
 203 }
 204
 205 } // namespace GL
 206 } // namespace Msp