source/core/vertexsetup.cpp

   1 #include <msp/core/raii.h>
   2 #include <msp/gl/extensions/arb_direct_state_access.h>
   3 #include <msp/gl/extensions/arb_instanced_arrays.h>
   4 #include <msp/gl/extensions/arb_vertex_array_object.h>
   5 #include <msp/gl/extensions/arb_vertex_attrib_binding.h>
   6 #include <msp/gl/extensions/arb_vertex_buffer_object.h>
   7 #include <msp/gl/extensions/arb_vertex_shader.h>
   8 #include "buffer.h"
   9 #include "error.h"
  10 #include "gl.h"
  11 #include "misc.h"
  12 #include "vertexarray.h"
  13 #include "vertexsetup.h"
  14
  15 using namespace std;
  16
  17 namespace Msp {
  18 namespace GL {
  19
  20 VertexSetup::VertexSetup():
  21         dirty(0),
  22         vertex_array(0),
  23         inst_array(0),
  24         index_buffer(0)
  25 {
  26         static Require req(ARB_vertex_array_object);
  27         if(ARB_direct_state_access)
  28                 glCreateVertexArrays(1, &id);
  29         else
  30                 glGenVertexArrays(1, &id);
  31 }
  32
  33 VertexSetup::~VertexSetup()
  34 {
  35         if(current()==this)
  36                 unbind();
  37         glDeleteVertexArrays(1, &id);
  38 }
  39
  40 void VertexSetup::set_vertex_array(const VertexArray &a)
  41 {
  42         if(!verify_array(a))
  43                 throw invalid_argument("VertexSetup::set_vertex_array");
  44
  45         vertex_array = &a;
  46         update(get_update_mask(VERTEX_ARRAY, vertex_format, *vertex_array));
  47         vertex_format = vertex_array->get_format();
  48 }
  49
  50 void VertexSetup::set_instance_array(const VertexArray *a)
  51 {
  52         if(a)
  53         {
  54                 if(!verify_array(*a))
  55                         throw invalid_argument("VertexSetup::set_instance_array");
  56
  57                 static Require req(ARB_instanced_arrays);
  58         }
  59
  60         inst_array = a;
  61         update(get_update_mask(INSTANCE_ARRAY, inst_format, *inst_array));
  62         inst_format = inst_array->get_format();
  63 }
  64
  65 void VertexSetup::set_index_buffer(const Buffer &ibuf)
  66 {
  67         index_buffer = &ibuf;
  68         update(INDEX_BUFFER);
  69 }
  70
  71 void VertexSetup::refresh()
  72 {
  73         if(vertex_array && vertex_array->get_format()!=vertex_format)
  74                 set_vertex_array(*vertex_array);
  75
  76         if(inst_array && inst_array->get_format()!=inst_format)
  77                 set_instance_array(inst_array);
  78 }
  79
  80 bool VertexSetup::verify_array(const VertexArray &array)
  81 {
  82         if(!array.get_buffer())
  83                 return false;
  84
  85         static int max_attribs = -1;
  86         if(max_attribs<0)
  87                 max_attribs = get_i(GL_MAX_VERTEX_ATTRIBS);
  88
  89         const VertexFormat &fmt = array.get_format();
  90         for(const unsigned char *a=fmt.begin(); a!=fmt.end(); ++a)
  91                 if(static_cast<int>(get_attribute_semantic(*a))>=max_attribs)
  92                         return false;
  93
  94         return true;
  95 }
  96
  97 unsigned VertexSetup::get_attribs(const VertexFormat &fmt)
  98 {
  99         unsigned mask = 0;
 100         for(const unsigned char *a=fmt.begin(); a!=fmt.end(); ++a)
 101                 mask |= 1<<get_attribute_semantic(*a);
 102         return mask;
 103 }
 104
 105 unsigned VertexSetup::get_update_mask(unsigned base, const VertexFormat &cur_fmt, const VertexArray &new_array)
 106 {
 107         unsigned unused = get_attribs(cur_fmt)&~get_attribs(new_array.get_format());
 108         return base | (unused ? UNUSED_ATTRIBS | (unused<<ATTRIB_SHIFT) : 0);
 109 }
 110
 111 void VertexSetup::update(unsigned mask) const
 112 {
 113         static bool direct = ARB_direct_state_access && ARB_vertex_attrib_binding;
 114         if(!direct && current()!=this)
 115         {
 116                 dirty |= mask;
 117                 return;
 118         }
 119
 120         if(mask&UNUSED_ATTRIBS)
 121         {
 122                 for(unsigned i=0, am=mask>>ATTRIB_SHIFT; am; ++i, am>>=1)
 123                         if(am&1)
 124                         {
 125                                 if(direct)
 126                                         glDisableVertexArrayAttrib(id, i);
 127                                 else
 128                                         glDisableVertexAttribArray(i);
 129                         }
 130         }
 131
 132         if(mask&VERTEX_ARRAY)
 133                 update_vertex_array(*vertex_array, 0, 0, direct);
 134
 135         if((mask&INSTANCE_ARRAY) && inst_array)
 136                 update_vertex_array(*inst_array, 1, 1, direct);
 137
 138         if(mask&INDEX_BUFFER)
 139         {
 140                 if(direct)
 141                         glVertexArrayElementBuffer(id, index_buffer->get_id());
 142                 else
 143                         glBindBuffer(ELEMENT_ARRAY_BUFFER, index_buffer->get_id());
 144         }
 145 }
 146
 147 void VertexSetup::update_vertex_array(const VertexArray &array, unsigned binding, unsigned divisor, bool direct) const
 148 {
 149         Conditional<Bind> bind_vbuf(!direct, array.get_buffer(), ARRAY_BUFFER);
 150
 151         const VertexFormat &fmt = array.get_format();
 152         unsigned stride = fmt.stride()*sizeof(float);
 153         if(direct)
 154         {
 155                 glVertexArrayVertexBuffer(id, binding, array.get_buffer()->get_id(), 0, stride);
 156                 glVertexArrayBindingDivisor(id, binding, divisor);
 157         }
 158
 159         unsigned offset = 0;
 160         for(const unsigned char *a=fmt.begin(); a!=fmt.end(); ++a)
 161         {
 162                 unsigned sem = get_attribute_semantic(*a);
 163                 unsigned sz = get_attribute_size(*a);
 164                 if(direct)
 165                 {
 166                         if(*a==COLOR4_UBYTE)
 167                                 glVertexArrayAttribFormat(id, sem, 4, GL_UNSIGNED_BYTE, true, offset);
 168                         else
 169                                 glVertexArrayAttribFormat(id, sem, sz, GL_FLOAT, false, offset);
 170                         glVertexArrayAttribBinding(id, sem, binding);
 171                         glEnableVertexArrayAttrib(id, sem);
 172                 }
 173                 else
 174                 {
 175                         if(*a==COLOR4_UBYTE)
 176                                 glVertexAttribPointer(sem, 4, GL_UNSIGNED_BYTE, true, stride, reinterpret_cast<unsigned char *>(offset));
 177                         else
 178                                 glVertexAttribPointer(sem, sz, GL_FLOAT, false, stride, reinterpret_cast<float *>(offset));
 179                         if(ARB_instanced_arrays)
 180                                 glVertexAttribDivisor(sem, divisor);
 181                         glEnableVertexAttribArray(sem);
 182                 }
 183                 offset += sz*sizeof(float);
 184         }
 185 }
 186
 187 void VertexSetup::bind() const
 188 {
 189         if(!vertex_array || !index_buffer)
 190                 throw invalid_operation("VertexSetup::bind");
 191
 192         if(set_current(this))
 193         {
 194                 vertex_array->refresh();
 195                 if(inst_array)
 196                         inst_array->refresh();
 197                 glBindVertexArray(id);
 198                 if(dirty)
 199                 {
 200                         update(dirty);
 201                         dirty = 0;
 202                 }
 203         }
 204 }
 205
 206 void VertexSetup::unbind()
 207 {
 208         if(set_current(0))
 209                 glBindVertexArray(0);
 210 }
 211
 212 } // namespace GL
 213 } // namespace Msp