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         vertices.refresh();
  80         if(dirty)
  81         {
  82                 if(dirty&1)
  83                 {
  84                         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
  85                                 i->refresh();
  86                 }
  87
  88                 if(dirty&2)
  89                 {
  90                         Bind bind_vbuf(vbuf, ARRAY_BUFFER);
  91
  92                         bool bind_here = !current();
  93                         if(bind_here)
  94                                 glBindVertexArray(vao_id);
  95
  96                         const VertexFormat &fmt = vertices.get_format();
  97                         unsigned stride = get_stride(fmt)*sizeof(float);
  98                         float *ptr = 0;
  99                         for(const unsigned char *c=fmt.begin(); c!=fmt.end(); ++c)
 100                         {
 101                                 unsigned t = get_component_type(*c);
 102                                 if(t>=get_component_type(ATTRIB1))
 103                                         t -= get_component_type(ATTRIB1);
 104                                 unsigned sz = get_component_size(*c);
 105                                 if(*c==COLOR4_UBYTE)
 106                                         glVertexAttribPointer(t, 4, GL_UNSIGNED_BYTE, true, stride, ptr);
 107                                 else
 108                                         glVertexAttribPointer(t, sz, GL_FLOAT, false, stride, ptr);
 109                                 glEnableVertexAttribArray(t);
 110                                 ptr += sz;
 111                         }
 112                         glBindBuffer(ELEMENT_ARRAY_BUFFER, ibuf->get_id());
 113
 114                         if(bind_here)
 115                                 glBindVertexArray(0);
 116                 }
 117
 118                 dirty = 0;
 119         }
 120 }
 121
 122 unsigned Mesh::get_n_vertices() const
 123 {
 124         return vertices.size();
 125 }
 126
 127 float *Mesh::modify_vertex(unsigned i)
 128 {
 129         return vertices.modify(i);
 130 }
 131
 132 void Mesh::add_batch(const Batch &b)
 133 {
 134         if(defer_buffers)
 135                 create_buffers();
 136
 137         dirty |= 1;
 138         if(!batches.empty() && batches.back().can_append(b.get_type()))
 139                 batches.back().append(b);
 140         else
 141         {
 142                 Batch *prev = (batches.empty() ? 0 : &batches.back());
 143                 batches.push_back(b);
 144                 if(ibuf)
 145                         batches.back().use_buffer(ibuf, prev);
 146         }
 147 }
 148
 149 void Mesh::set_winding(const WindingTest *w)
 150 {
 151         winding = w;
 152 }
 153
 154 void Mesh::draw() const
 155 {
 156         const Mesh *cur = current();
 157         if(cur && cur!=this)
 158                 throw invalid_operation("Mesh::draw");
 159
 160         refresh();
 161
 162         if(!current())
 163                 vertices.apply();
 164         Bind bind_ibuf(ibuf, ELEMENT_ARRAY_BUFFER);
 165         Bind bind_winding(winding);
 166
 167         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
 168                 i->draw();
 169 }
 170
 171 void Mesh::draw(Renderer &renderer) const
 172 {
 173         refresh();
 174
 175         renderer.set_mesh(this);
 176         renderer.set_element_buffer(ibuf);
 177         renderer.set_winding_test(winding);
 178
 179         for(list<Batch>::const_iterator i=batches.begin(); i!=batches.end(); ++i)
 180                 renderer.draw(*i);
 181 }
 182
 183 void Mesh::bind() const
 184 {
 185         /* If VAOs are not supported, vao_id is zero and set_current won't get
 186         called.  Thus unbind won't try to call a null function either. */
 187         if(!vao_id)
 188                 unbind();
 189         else if(set_current(this))
 190                 glBindVertexArray(vao_id);
 191 }
 192
 193 void Mesh::unbind()
 194 {
 195         if(set_current(0))
 196                 glBindVertexArray(0);
 197 }
 198
 199
 200 Mesh::Loader::Loader(Mesh &m):
 201         DataFile::ObjectLoader<Mesh>(m)
 202 {
 203         add("batch",    &Loader::batch);
 204         add("vertices", &Loader::vertices);
 205         add("winding",  &Loader::winding);
 206 }
 207
 208 void Mesh::Loader::vertices(const vector<VertexComponent> &c)
 209 {
 210         if(c.empty())
 211                 throw invalid_argument("No vertex components");
 212
 213         VertexFormat fmt;
 214         for(vector<VertexComponent>::const_iterator i=c.begin(); i!=c.end(); ++i)
 215                 fmt = (fmt, *i);
 216         obj.vertices.reset(fmt);
 217         obj.dirty |= 2;
 218         load_sub(obj.vertices);
 219 }
 220
 221 void Mesh::Loader::batch(PrimitiveType p)
 222 {
 223         Batch btc(p);
 224         load_sub(btc);
 225         obj.add_batch(btc);
 226 }
 227
 228 void Mesh::Loader::winding(FaceWinding w)
 229 {
 230         if(w==CLOCKWISE)
 231                 obj.winding = &WindingTest::clockwise();
 232         else if(w==COUNTERCLOCKWISE)
 233                 obj.winding = &WindingTest::counterclockwise();
 234 }
 235
 236 } // namespace GL
 237 } // namespace Msp