source/renderer.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2011  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include <msp/core/except.h>
   9 #include "batch.h"
  10 #include "buffer.h"
  11 #include "camera.h"
  12 #include "material.h"
  13 #include "program.h"
  14 #include "programdata.h"
  15 #include "renderer.h"
  16 #include "texture.h"
  17 #include "texturing.h"
  18 #include "vertexarray.h"
  19
  20 using namespace std;
  21
  22 namespace Msp {
  23 namespace GL {
  24
  25 Renderer::Renderer(const Camera *c):
  26         mtx_changed(false),
  27         camera(c),
  28         state_stack(1),
  29         state(&state_stack.back()),
  30         vertex_array(0),
  31         vertex_array_changed(false),
  32         element_buffer(0)
  33 {
  34         MatrixStack::modelview().push();
  35         if(camera)
  36         {
  37                 MatrixStack::projection().push();
  38                 camera->apply();
  39                 mtx_stack = camera->get_matrix();
  40         }
  41         else
  42                 mtx_stack = MatrixStack::modelview().top();
  43 }
  44
  45 Renderer::~Renderer()
  46 {
  47         if(camera)
  48                 MatrixStack::projection().pop();
  49         MatrixStack::modelview().pop();
  50
  51         Texturing::unbind();
  52         Texture::unbind_from(0);
  53         Material::unbind();
  54         Program::unbind();
  55         Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
  56 }
  57
  58 MatrixStack &Renderer::matrix_stack()
  59 {
  60         mtx_changed = true;
  61         return mtx_stack;
  62 }
  63
  64 void Renderer::set_texture(const Texture *t)
  65 {
  66         state->texture = t;
  67         state->texturing = 0;
  68 }
  69
  70 void Renderer::set_texturing(const Texturing *t)
  71 {
  72         state->texturing = t;
  73         state->texture = 0;
  74 }
  75
  76 void Renderer::set_material(const Material *m)
  77 {
  78         state->material = m;
  79 }
  80
  81 void Renderer::set_shader(const Program *p, const ProgramData *d)
  82 {
  83         state->shprog = p;
  84         if(d)
  85                 state->shdata.assign(1, d);
  86         else
  87                 state->shdata.clear();
  88 }
  89
  90 void Renderer::add_shader_data(const ProgramData *d)
  91 {
  92         if(!state->shprog)
  93                 throw InvalidState("No shader program");
  94
  95         state->shdata.push_back(d);
  96 }
  97
  98 void Renderer::set_vertex_array(const VertexArray *a)
  99 {
 100         vertex_array_changed = (a!=vertex_array);
 101         vertex_array = a;
 102 }
 103
 104 void Renderer::set_element_buffer(const Buffer *b)
 105 {
 106         element_buffer = b;
 107 }
 108
 109 void Renderer::push_state()
 110 {
 111         state_stack.push_back(state_stack.back());
 112         state = &state_stack.back();
 113         mtx_stack.push();
 114 }
 115
 116 void Renderer::pop_state()
 117 {
 118         if(state_stack.size()==1)
 119                 throw InvalidState("Can't pop the last state");
 120
 121         state_stack.pop_back();
 122         state = &state_stack.back();
 123         mtx_stack.pop();
 124 }
 125
 126 void Renderer::escape()
 127 {
 128         apply_state();
 129         Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 130 }
 131
 132 void Renderer::draw(const Batch &batch)
 133 {
 134         if(!vertex_array)
 135                 throw InvalidState("Can't draw without a vertex array");
 136
 137         apply_state();
 138
 139         // Until VertexArray acquires VAO support and becomes Bindable
 140         if(vertex_array_changed)
 141                 vertex_array->apply();
 142
 143         if(element_buffer)
 144                 element_buffer->bind_to(ELEMENT_ARRAY_BUFFER);
 145         else
 146                 Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 147
 148         batch.draw();
 149 }
 150
 151 void Renderer::apply_state()
 152 {
 153         // We let the objects themselves figure out if the binding has changed
 154
 155         if(state->texturing)
 156                 state->texturing->bind();
 157         else
 158         {
 159                 Texturing::unbind();
 160                 if(state->texture)
 161                         state->texture->bind_to(0);
 162                 else
 163                         Texture::unbind_from(0);
 164         }
 165
 166         if(state->material)
 167                 state->material->bind();
 168         else
 169                 Material::unbind();
 170
 171         if(state->shprog)
 172         {
 173                 state->shprog->bind();
 174                 for(vector<const ProgramData *>::const_iterator i=state->shdata.begin(); i!=state->shdata.end(); ++i)
 175                         (*i)->apply();
 176         }
 177         else
 178                 Program::unbind();
 179
 180         if(mtx_changed)
 181         {
 182                 MatrixStack::modelview() = mtx_stack.top();
 183                 mtx_changed = false;
 184         }
 185 }
 186
 187
 188 Renderer::State::State():
 189         texture(0),
 190         texturing(0),
 191         material(0),
 192         shprog(0)
 193 { }
 194
 195 } // namespace GL
 196 } // namespace Msp