source/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 "vertexarray.h"
  12 #include "vertexsetup.h"
  13
  14 namespace Msp {
  15 namespace GL {
  16
  17 VertexSetup::VertexSetup():
  18         dirty(0),
  19         vertex_array(0),
  20         inst_array(0),
  21         index_buffer(0)
  22 {
  23         static Require req(ARB_vertex_array_object);
  24         if(ARB_direct_state_access)
  25                 glCreateVertexArrays(1, &id);
  26         else
  27                 glGenVertexArrays(1, &id);
  28 }
  29
  30 VertexSetup::~VertexSetup()
  31 {
  32         if(current()==this)
  33                 unbind();
  34         glDeleteVertexArrays(1, &id);
  35 }
  36
  37 void VertexSetup::set_vertex_array(const VertexArray &a)
  38 {
  39         vertex_array = &a;
  40         update(VERTEX_ARRAY);
  41 }
  42
  43 void VertexSetup::set_instance_array(const VertexArray *a)
  44 {
  45         if(a)
  46                 static Require req(ARB_instanced_arrays);
  47
  48         inst_array = a;
  49         update(INSTANCE_ARRAY);
  50 }
  51
  52 void VertexSetup::set_index_buffer(const Buffer &ibuf)
  53 {
  54         index_buffer = &ibuf;
  55         update(INDEX_BUFFER);
  56 }
  57
  58 void VertexSetup::update(unsigned mask) const
  59 {
  60         static bool direct = ARB_direct_state_access && ARB_vertex_attrib_binding;
  61         if(!direct && current()!=this)
  62         {
  63                 dirty |= mask;
  64                 return;
  65         }
  66
  67         if(mask&VERTEX_ARRAY)
  68                 update_vertex_array(*vertex_array, 0, 0, direct);
  69
  70         if(mask&INSTANCE_ARRAY)
  71         {
  72                 if(inst_array)
  73                         update_vertex_array(*inst_array, 1, 1, direct);
  74         }
  75
  76         if(mask&INDEX_BUFFER)
  77         {
  78                 if(direct)
  79                         glVertexArrayElementBuffer(id, index_buffer->get_id());
  80                 else
  81                         glBindBuffer(ELEMENT_ARRAY_BUFFER, index_buffer->get_id());
  82         }
  83 }
  84
  85 void VertexSetup::update_vertex_array(const VertexArray &array, unsigned binding, unsigned divisor, bool direct) const
  86 {
  87         Conditional<Bind> bind_vbuf(!direct, array.get_buffer(), ARRAY_BUFFER);
  88
  89         const VertexFormat &fmt = array.get_format();
  90         unsigned stride = get_stride(fmt)*sizeof(float);
  91         if(direct)
  92         {
  93                 glVertexArrayVertexBuffer(id, binding, array.get_buffer()->get_id(), 0, stride);
  94                 glVertexArrayBindingDivisor(id, binding, divisor);
  95         }
  96
  97         unsigned offset = 0;
  98         for(const unsigned char *c=fmt.begin(); c!=fmt.end(); ++c)
  99         {
 100                 unsigned t = get_component_type(*c);
 101                 if(t>=get_component_type(ATTRIB1))
 102                         t -= get_component_type(ATTRIB1);
 103                 unsigned sz = get_component_size(*c);
 104                 if(direct)
 105                 {
 106                         if(*c==COLOR4_UBYTE)
 107                                 glVertexArrayAttribFormat(id, t, 4, GL_UNSIGNED_BYTE, true, offset);
 108                         else
 109                                 glVertexArrayAttribFormat(id, t, sz, GL_FLOAT, false, offset);
 110                         glVertexArrayAttribBinding(id, t, binding);
 111                         glEnableVertexArrayAttrib(id, t);
 112                 }
 113                 else
 114                 {
 115                         if(*c==COLOR4_UBYTE)
 116                                 glVertexAttribPointer(t, 4, GL_UNSIGNED_BYTE, true, stride, reinterpret_cast<unsigned char *>(offset));
 117                         else
 118                                 glVertexAttribPointer(t, sz, GL_FLOAT, false, stride, reinterpret_cast<float *>(offset));
 119                         glVertexAttribDivisor(t, divisor);
 120                         glEnableVertexAttribArray(t);
 121                 }
 122                 offset += sz*sizeof(float);
 123         }
 124 }
 125
 126 void VertexSetup::bind() const
 127 {
 128         if(!vertex_array || !index_buffer)
 129                 throw invalid_operation("VertexSetup::bind");
 130
 131         if(set_current(this))
 132         {
 133                 glBindVertexArray(id);
 134                 if(dirty)
 135                 {
 136                         update(dirty);
 137                         dirty = 0;
 138                 }
 139         }
 140 }
 141
 142 void VertexSetup::unbind()
 143 {
 144         if(set_current(0))
 145                 glBindVertexArray(0);
 146 }
 147
 148 } // namespace GL
 149 } // namespace Msp