source/mesh.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2007-2010  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "buffer.h"
   9 #include "extension.h"
  10 #include "mesh.h"
  11
  12 using namespace std;
  13
  14 namespace Msp {
  15 namespace GL {
  16
  17 Mesh::Mesh():
  18         vertices(VERTEX3),
  19         ibuf(0),
  20         defer_ibuf(true)
  21 { }
  22
  23 Mesh::Mesh(const VertexFormat &f):
  24         vertices(f),
  25         ibuf(0),
  26         defer_ibuf(true)
  27 { }
  28
  29 Mesh::~Mesh()
  30 {
  31         delete ibuf;
  32 }
  33
  34 void Mesh::clear()
  35 {
  36         vertices.clear();
  37         batches.clear();
  38 }
  39
  40 void Mesh::use_buffers(bool b)
  41 {
  42         if(b)
  43         {
  44                 vertices.use_vertex_buffer();
  45                 if(!ibuf)
  46                         ibuf = new Buffer(ELEMENT_ARRAY_BUFFER);
  47                 defer_ibuf = false;
  48         }
  49         else
  50         {
  51                 vertices.use_vertex_buffer(0);
  52                 delete ibuf;
  53                 ibuf = 0;
  54                 defer_ibuf = false;
  55         }
  56 }
  57
  58 unsigned Mesh::get_n_vertices() const
  59 {
  60         return vertices.size();
  61 }
  62
  63 float *Mesh::modify_vertex(unsigned i)
  64 {
  65         return vertices.modify(i);
  66 }
  67
  68 void Mesh::add_batch(const Batch &b)
  69 {
  70         bool can_append = false;
  71         if(!batches.empty())
  72         {
  73                 PrimitiveType type = b.get_type();
  74                 can_append = (type==batches.back().get_type() &&
  75                         type!=LINE_STRIP && type!=LINE_LOOP && type!=POLYGON &&
  76                         (type!=TRIANGLE_FAN || is_supported("GL_NV_primitive_restart")));
  77         }
  78
  79         if(defer_ibuf)
  80         {
  81                 ibuf = new Buffer(ELEMENT_ARRAY_BUFFER);
  82                 defer_ibuf = false;
  83         }
  84
  85         if(can_append)
  86                 batches.back().append(b);
  87         else
  88         {
  89                 Batch *prev = (batches.empty() ? 0 : &batches.back());
  90                 batches.push_back(b);
  91                 if(ibuf)
  92                         batches.back().use_index_buffer(ibuf, prev);
  93         }
  94 }
  95
  96 void Mesh::draw() const
  97 {
  98         vertices.apply();
  99
 100         if(ibuf)
 101                 ibuf->bind_to(ELEMENT_ARRAY_BUFFER);
 102
 103         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
 104                 i->draw();
 105
 106         if(ibuf)
 107                 Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 108 }
 109
 110
 111 Mesh::Loader::Loader(Mesh &m):
 112         DataFile::ObjectLoader<Mesh>(m)
 113 {
 114         add("vertices", &Loader::vertices);
 115         add("batch",    &Loader::batch);
 116 }
 117
 118 void Mesh::Loader::vertices(VertexFormat f)
 119 {
 120         obj.vertices.reset(f);
 121         load_sub(obj.vertices);
 122 }
 123
 124 void Mesh::Loader::batch(PrimitiveType p)
 125 {
 126         Batch btc(p);
 127         load_sub(btc);
 128         obj.add_batch(btc);
 129 }
 130
 131 } // namespace GL
 132 } // namespace Msp