source/renderer.cpp

   1 #include "batch.h"
   2 #include "buffer.h"
   3 #include "camera.h"
   4 #include "error.h"
   5 #include "material.h"
   6 #include "program.h"
   7 #include "programdata.h"
   8 #include "renderer.h"
   9 #include "texture.h"
  10 #include "texturing.h"
  11 #include "vertexarray.h"
  12 #include "windingtest.h"
  13
  14 using namespace std;
  15
  16 namespace Msp {
  17 namespace GL {
  18
  19 Renderer::Renderer(const Camera *c):
  20         mtx_stack(*this),
  21         mtx_changed(false),
  22         camera(c),
  23         state_stack(1),
  24         vertex_array(0),
  25         vertex_array_changed(false),
  26         element_buffer(0)
  27 {
  28         state_stack.reserve(16);
  29         shdata_stack.reserve(32);
  30         state = &state_stack.back();
  31
  32         MatrixStack::modelview().push();
  33         if(camera)
  34         {
  35                 MatrixStack::projection().push();
  36                 camera->apply();
  37                 mtx_stack.load(camera->get_matrix());
  38         }
  39         else
  40                 mtx_stack.load(MatrixStack::modelview().top());
  41 }
  42
  43 Renderer::~Renderer()
  44 {
  45         if(camera)
  46                 MatrixStack::projection().pop();
  47         MatrixStack::modelview().pop();
  48
  49         Texturing::unbind();
  50         Texture::unbind_from(0);
  51         Material::unbind();
  52         Program::unbind();
  53         Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
  54         WindingTest::unbind();
  55 }
  56
  57 void Renderer::set_texture(const Texture *t)
  58 {
  59         state->texture = t;
  60         state->texturing = 0;
  61 }
  62
  63 void Renderer::set_texturing(const Texturing *t)
  64 {
  65         state->texturing = t;
  66         state->texture = 0;
  67 }
  68
  69 void Renderer::set_material(const Material *m)
  70 {
  71         state->material = m;
  72 }
  73
  74 void Renderer::set_shader_program(const Program *p, const ProgramData *d)
  75 {
  76         state->shprog = p;
  77         if(p && d)
  78                 add_shader_data(*d);
  79
  80         /* Even if we have no new shdata, the existing ones need to be re-applied
  81         to the new program */
  82         shdata_changed = true;
  83 }
  84
  85 void Renderer::add_shader_data(const ProgramData &d)
  86 {
  87         shdata_stack.push_back(&d);
  88         state->shdata_count = shdata_stack.size();
  89         shdata_changed = true;
  90 }
  91
  92 void Renderer::set_vertex_array(const VertexArray *a)
  93 {
  94         vertex_array_changed = (a!=vertex_array);
  95         vertex_array = a;
  96 }
  97
  98 void Renderer::set_element_buffer(const Buffer *b)
  99 {
 100         element_buffer = b;
 101 }
 102
 103 void Renderer::set_winding_test(const WindingTest *w)
 104 {
 105         state->winding_test = w;
 106 }
 107
 108 void Renderer::push_state()
 109 {
 110         state_stack.push_back(state_stack.back());
 111         state = &state_stack.back();
 112         mtx_stack.push();
 113 }
 114
 115 void Renderer::pop_state()
 116 {
 117         if(state_stack.size()==1)
 118                 throw stack_underflow("Renderer::pop_state");
 119
 120         state_stack.pop_back();
 121         state = &state_stack.back();
 122         if(shdata_stack.size()>state->shdata_count)
 123                 shdata_stack.erase(shdata_stack.begin()+state->shdata_count, shdata_stack.end());
 124         mtx_stack.pop();
 125         mtx_changed = true;
 126         shdata_changed = true;
 127 }
 128
 129 void Renderer::escape()
 130 {
 131         apply_state();
 132         Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 133 }
 134
 135 void Renderer::draw(const Batch &batch)
 136 {
 137         if(!vertex_array)
 138                 throw invalid_operation("Renderer::draw");
 139
 140         apply_state();
 141
 142         // Until VertexArray acquires VAO support and becomes Bindable
 143         if(vertex_array_changed)
 144         {
 145                 vertex_array->apply();
 146                 vertex_array_changed = false;
 147         }
 148
 149         if(element_buffer)
 150                 element_buffer->bind_to(ELEMENT_ARRAY_BUFFER);
 151         else
 152                 Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 153
 154         batch.draw();
 155 }
 156
 157 void Renderer::apply_state()
 158 {
 159         // We let the objects themselves figure out if the binding has changed
 160
 161         if(state->texturing)
 162                 state->texturing->bind();
 163         else
 164         {
 165                 Texturing::unbind();
 166                 if(state->texture)
 167                         state->texture->bind_to(0);
 168                 else
 169                         Texture::unbind_from(0);
 170         }
 171
 172         if(state->material)
 173                 state->material->bind();
 174         else
 175                 Material::unbind();
 176
 177         if(state->shprog)
 178         {
 179                 state->shprog->bind();
 180                 if(shdata_changed)
 181                 {
 182                         for(vector<const ProgramData *>::const_iterator i=shdata_stack.begin(); i!=shdata_stack.end(); ++i)
 183                                 (*i)->apply();
 184                         shdata_changed = false;
 185                 }
 186         }
 187         else
 188                 Program::unbind();
 189
 190         if(state->winding_test)
 191                 state->winding_test->bind();
 192         else
 193                 WindingTest::unbind();
 194
 195         if(mtx_changed)
 196         {
 197                 MatrixStack::modelview() = mtx_stack.top();
 198                 mtx_changed = false;
 199         }
 200 }
 201
 202
 203 Renderer::State::State():
 204         texture(0),
 205         texturing(0),
 206         material(0),
 207         shprog(0),
 208         shdata_count(0),
 209         winding_test(0)
 210 { }
 211
 212
 213 Renderer::MtxStack::MtxStack(Renderer &r):
 214         renderer(r)
 215 { }
 216
 217 void Renderer::MtxStack::update()
 218 {
 219         renderer.mtx_changed = true;
 220 }
 221
 222 } // namespace GL
 223 } // namespace Msp