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