source/renderer.cpp

   1 #include <msp/core/except.h>
   2 #include "batch.h"
   3 #include "buffer.h"
   4 #include "camera.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         state(&state_stack.back()),
  25         vertex_array(0),
  26         vertex_array_changed(false),
  27         element_buffer(0)
  28 {
  29         MatrixStack::modelview().push();
  30         if(camera)
  31         {
  32                 MatrixStack::projection().push();
  33                 camera->apply();
  34                 mtx_stack.load(camera->get_matrix());
  35         }
  36         else
  37                 mtx_stack.load(MatrixStack::modelview().top());
  38 }
  39
  40 Renderer::~Renderer()
  41 {
  42         if(camera)
  43                 MatrixStack::projection().pop();
  44         MatrixStack::modelview().pop();
  45
  46         Texturing::unbind();
  47         Texture::unbind_from(0);
  48         Material::unbind();
  49         Program::unbind();
  50         Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
  51         WindingTest::unbind();
  52 }
  53
  54 void Renderer::set_texture(const Texture *t)
  55 {
  56         state->texture = t;
  57         state->texturing = 0;
  58 }
  59
  60 void Renderer::set_texturing(const Texturing *t)
  61 {
  62         state->texturing = t;
  63         state->texture = 0;
  64 }
  65
  66 void Renderer::set_material(const Material *m)
  67 {
  68         state->material = m;
  69 }
  70
  71 void Renderer::set_shader(const Program *p, const ProgramData *d)
  72 {
  73         state->shprog = p;
  74         if(d)
  75                 state->shdata.assign(1, d);
  76         else
  77                 state->shdata.clear();
  78 }
  79
  80 void Renderer::add_shader_data(const ProgramData *d)
  81 {
  82         if(!state->shprog)
  83                 throw InvalidState("No shader program");
  84
  85         state->shdata.push_back(d);
  86 }
  87
  88 void Renderer::set_vertex_array(const VertexArray *a)
  89 {
  90         vertex_array_changed = (a!=vertex_array);
  91         vertex_array = a;
  92 }
  93
  94 void Renderer::set_element_buffer(const Buffer *b)
  95 {
  96         element_buffer = b;
  97 }
  98
  99 void Renderer::set_winding_test(const WindingTest *w)
 100 {
 101         state->winding_test = w;
 102 }
 103
 104 void Renderer::push_state()
 105 {
 106         state_stack.push_back(state_stack.back());
 107         state = &state_stack.back();
 108         mtx_stack.push();
 109 }
 110
 111 void Renderer::pop_state()
 112 {
 113         if(state_stack.size()==1)
 114                 throw InvalidState("Can't pop the last state");
 115
 116         state_stack.pop_back();
 117         state = &state_stack.back();
 118         mtx_stack.pop();
 119         mtx_changed = true;
 120 }
 121
 122 void Renderer::escape()
 123 {
 124         apply_state();
 125         Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 126 }
 127
 128 void Renderer::draw(const Batch &batch)
 129 {
 130         if(!vertex_array)
 131                 throw InvalidState("Can't draw without a vertex array");
 132
 133         apply_state();
 134
 135         // Until VertexArray acquires VAO support and becomes Bindable
 136         if(vertex_array_changed)
 137         {
 138                 vertex_array->apply();
 139                 vertex_array_changed = false;
 140         }
 141
 142         if(element_buffer)
 143                 element_buffer->bind_to(ELEMENT_ARRAY_BUFFER);
 144         else
 145                 Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 146
 147         batch.draw();
 148 }
 149
 150 void Renderer::apply_state()
 151 {
 152         // We let the objects themselves figure out if the binding has changed
 153
 154         if(state->texturing)
 155                 state->texturing->bind();
 156         else
 157         {
 158                 Texturing::unbind();
 159                 if(state->texture)
 160                         state->texture->bind_to(0);
 161                 else
 162                         Texture::unbind_from(0);
 163         }
 164
 165         if(state->material)
 166                 state->material->bind();
 167         else
 168                 Material::unbind();
 169
 170         if(state->shprog)
 171         {
 172                 state->shprog->bind();
 173                 for(vector<const ProgramData *>::const_iterator i=state->shdata.begin(); i!=state->shdata.end(); ++i)
 174                         (*i)->apply();
 175         }
 176         else
 177                 Program::unbind();
 178
 179         if(state->winding_test)
 180                 state->winding_test->bind();
 181         else
 182                 WindingTest::unbind();
 183
 184         if(mtx_changed)
 185         {
 186                 MatrixStack::modelview() = mtx_stack.top();
 187                 mtx_changed = false;
 188         }
 189 }
 190
 191
 192 Renderer::State::State():
 193         texture(0),
 194         texturing(0),
 195         material(0),
 196         shprog(0),
 197         winding_test(0)
 198 { }
 199
 200
 201 Renderer::MtxStack::MtxStack(Renderer &r):
 202         renderer(r)
 203 { }
 204
 205 void Renderer::MtxStack::update()
 206 {
 207         renderer.mtx_changed = true;
 208 }
 209
 210 } // namespace GL
 211 } // namespace Msp