source/mesh.cpp

   1 #include <msp/gl/extensions/arb_vertex_array_object.h>
   2 #include <msp/gl/extensions/arb_vertex_shader.h>
   3 #include "buffer.h"
   4 #include "error.h"
   5 #include "mesh.h"
   6 #include "renderer.h"
   7
   8 using namespace std;
   9
  10 namespace Msp {
  11 namespace GL {
  12
  13 Mesh::Mesh():
  14         vertices(VERTEX3),
  15         vbuf(0),
  16         ibuf(0),
  17         vao_id(0),
  18         defer_buffers(true),
  19         dirty(0),
  20         winding(0)
  21 { }
  22
  23 Mesh::Mesh(const VertexFormat &f):
  24         vertices(f),
  25         vbuf(0),
  26         ibuf(0),
  27         vao_id(0),
  28         defer_buffers(true),
  29         dirty(2),
  30         winding(0)
  31 { }
  32
  33 Mesh::~Mesh()
  34 {
  35         delete vbuf;
  36         delete ibuf;
  37         if(vao_id)
  38                 glDeleteVertexArrays(1, &vao_id);
  39 }
  40
  41 void Mesh::clear()
  42 {
  43         vertices.clear();
  44         batches.clear();
  45 }
  46
  47 void Mesh::use_buffers(bool b)
  48 {
  49         defer_buffers = false;
  50         if(b)
  51                 create_buffers();
  52         else
  53         {
  54                 vertices.use_buffer(0);
  55                 delete vbuf;
  56                 vbuf = 0;
  57                 delete ibuf;
  58                 ibuf = 0;
  59         }
  60 }
  61
  62 void Mesh::create_buffers()
  63 {
  64         defer_buffers = false;
  65
  66         if(!vbuf)
  67                 vbuf = new Buffer(ARRAY_BUFFER);
  68         vertices.use_buffer(vbuf);
  69
  70         if(!ibuf)
  71                 ibuf = new Buffer(ELEMENT_ARRAY_BUFFER);
  72
  73         if(ARB_vertex_array_object && !vao_id)
  74                 glGenVertexArrays(1, &vao_id);
  75 }
  76
  77 void Mesh::refresh() const
  78 {
  79         if(!vbuf)
  80                 return;
  81
  82         vertices.refresh();
  83         if(dirty)
  84         {
  85                 if(dirty&1)
  86                 {
  87                         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
  88                                 i->refresh();
  89                 }
  90
  91                 if(dirty&2)
  92                 {
  93                         Bind bind_vbuf(vbuf, ARRAY_BUFFER);
  94
  95                         bool bind_here = !current();
  96                         if(bind_here)
  97                                 glBindVertexArray(vao_id);
  98
  99                         const VertexFormat &fmt = vertices.get_format();
 100                         unsigned stride = get_stride(fmt)*sizeof(float);
 101                         float *ptr = 0;
 102                         for(const unsigned char *c=fmt.begin(); c!=fmt.end(); ++c)
 103                         {
 104                                 unsigned t = get_component_type(*c);
 105                                 if(t>=get_component_type(ATTRIB1))
 106                                         t -= get_component_type(ATTRIB1);
 107                                 unsigned sz = get_component_size(*c);
 108                                 if(*c==COLOR4_UBYTE)
 109                                         glVertexAttribPointer(t, 4, GL_UNSIGNED_BYTE, true, stride, ptr);
 110                                 else
 111                                         glVertexAttribPointer(t, sz, GL_FLOAT, false, stride, ptr);
 112                                 glEnableVertexAttribArray(t);
 113                                 ptr += sz;
 114                         }
 115                         glBindBuffer(ELEMENT_ARRAY_BUFFER, ibuf->get_id());
 116
 117                         if(bind_here)
 118                                 glBindVertexArray(0);
 119                 }
 120
 121                 dirty = 0;
 122         }
 123 }
 124
 125 unsigned Mesh::get_n_vertices() const
 126 {
 127         return vertices.size();
 128 }
 129
 130 float *Mesh::modify_vertex(unsigned i)
 131 {
 132         return vertices.modify(i);
 133 }
 134
 135 void Mesh::add_batch(const Batch &b)
 136 {
 137         if(defer_buffers)
 138                 create_buffers();
 139
 140         dirty |= 1;
 141         if(!batches.empty() && batches.back().can_append(b.get_type()))
 142                 batches.back().append(b);
 143         else
 144         {
 145                 Batch *prev = (batches.empty() ? 0 : &batches.back());
 146                 batches.push_back(b);
 147                 if(ibuf)
 148                         batches.back().use_buffer(ibuf, prev);
 149         }
 150 }
 151
 152 void Mesh::set_winding(const WindingTest *w)
 153 {
 154         winding = w;
 155 }
 156
 157 void Mesh::draw() const
 158 {
 159         const Mesh *cur = current();
 160         if(cur && cur!=this)
 161                 throw invalid_operation("Mesh::draw");
 162
 163         refresh();
 164
 165         if(!current())
 166                 vertices.apply();
 167         Bind bind_ibuf(ibuf, ELEMENT_ARRAY_BUFFER);
 168         Bind bind_winding(winding);
 169
 170         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
 171                 i->draw();
 172 }
 173
 174 void Mesh::draw(Renderer &renderer) const
 175 {
 176         refresh();
 177
 178         renderer.set_mesh(this);
 179         renderer.set_element_buffer(ibuf);
 180         renderer.set_winding_test(winding);
 181
 182         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
 183                 renderer.draw(*i);
 184 }
 185
 186 void Mesh::bind() const
 187 {
 188         /* If VAOs are not supported, vao_id is zero and set_current won't get
 189         called.  Thus unbind won't try to call a null function either. */
 190         if(!vao_id)
 191                 unbind();
 192         else if(set_current(this))
 193                 glBindVertexArray(vao_id);
 194 }
 195
 196 void Mesh::unbind()
 197 {
 198         if(set_current(0))
 199                 glBindVertexArray(0);
 200 }
 201
 202
 203 Mesh::Loader::Loader(Mesh &m):
 204         DataFile::ObjectLoader<Mesh>(m)
 205 {
 206         add("batch",    &Loader::batch);
 207         add("vertices", &Loader::vertices);
 208         add("winding",  &Loader::winding);
 209 }
 210
 211 void Mesh::Loader::vertices(const vector<VertexComponent> &c)
 212 {
 213         if(c.empty())
 214                 throw invalid_argument("No vertex components");
 215
 216         VertexFormat fmt;
 217         for(vector<VertexComponent>::const_iterator i=c.begin(); i!=c.end(); ++i)
 218                 fmt = (fmt, *i);
 219         obj.vertices.reset(fmt);
 220         obj.dirty |= 2;
 221         load_sub(obj.vertices);
 222 }
 223
 224 void Mesh::Loader::batch(PrimitiveType p)
 225 {
 226         Batch btc(p);
 227         load_sub(btc);
 228         obj.add_batch(btc);
 229 }
 230
 231 void Mesh::Loader::winding(FaceWinding w)
 232 {
 233         if(w==CLOCKWISE)
 234                 obj.winding = &WindingTest::clockwise();
 235         else if(w==COUNTERCLOCKWISE)
 236                 obj.winding = &WindingTest::counterclockwise();
 237 }
 238
 239 } // namespace GL
 240 } // namespace Msp