source/backends/opengl/vertexsetup_backend.cpp

   1 #include <algorithm>
   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 <msp/gl/extensions/ext_gpu_shader4.h>
   9 #include <msp/gl/extensions/khr_debug.h>
  10 #include "buffer.h"
  11 #include "vertexarray.h"
  12 #include "vertexformat.h"
  13 #include "vertexsetup.h"
  14 #include "vertexsetup_backend.h"
  15
  16 using namespace std;
  17
  18 namespace Msp {
  19 namespace GL {
  20
  21 OpenGLVertexSetup::OpenGLVertexSetup()
  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 OpenGLVertexSetup::OpenGLVertexSetup(OpenGLVertexSetup &&other):
  31         id(other.id)
  32 {
  33         other.id = 0;
  34 }
  35
  36 OpenGLVertexSetup::~OpenGLVertexSetup()
  37 {
  38         if(id)
  39                 glDeleteVertexArrays(1, &id);
  40 }
  41
  42 void OpenGLVertexSetup::require_format(const VertexFormat &fmt, bool instanced)
  43 {
  44         if(any_of(fmt.begin(), fmt.end(), is_integer_attribute))
  45                 static Require _req(EXT_gpu_shader4);
  46         if(instanced)
  47                 static Require req(ARB_instanced_arrays);
  48 }
  49
  50 void OpenGLVertexSetup::update(unsigned mask) const
  51 {
  52         static bool direct = ARB_direct_state_access && ARB_vertex_attrib_binding;
  53
  54         const VertexSetup &self = *static_cast<const VertexSetup *>(this);
  55
  56         if(mask&VertexSetup::VERTEX_ARRAY)
  57                 update_vertex_array(*self.vertex_array, 0, 0, direct);
  58
  59         if(mask&VertexSetup::INSTANCE_ARRAY)
  60                 update_vertex_array(*self.inst_array, 1, 1, direct);
  61
  62         if(mask&VertexSetup::INDEX_BUFFER)
  63         {
  64                 unsigned buf_id = self.index_buffer->id;
  65                 if(direct)
  66                         glVertexArrayElementBuffer(id, buf_id);
  67                 else
  68                         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, buf_id);
  69         }
  70 }
  71
  72 void OpenGLVertexSetup::update_vertex_array(const VertexArray &array, unsigned binding, unsigned divisor, bool direct) const
  73 {
  74         if(!direct)
  75         {
  76                 OpenGLBuffer::unbind_scratch();
  77                 glBindBuffer(GL_ARRAY_BUFFER, array.get_buffer()->id);
  78         }
  79
  80         const VertexFormat &fmt = array.get_format();
  81         unsigned stride = fmt.stride();
  82         if(direct)
  83         {
  84                 glVertexArrayVertexBuffer(id, binding, array.get_buffer()->id, 0, stride);
  85                 glVertexArrayBindingDivisor(id, binding, divisor);
  86         }
  87
  88         unsigned offset = array.get_offset();
  89         for(VertexAttribute a: fmt)
  90         {
  91                 unsigned sem = get_attribute_semantic(a);
  92                 if(!is_padding(a))
  93                 {
  94                         bool integer = is_integer_attribute(a);
  95                         GLenum type = get_gl_type(get_attribute_source_type(a));
  96                         unsigned cc = get_attribute_component_count(a);
  97                         if(direct)
  98                         {
  99                                 if(integer)
 100                                         glVertexArrayAttribIFormat(id, sem, cc, type, offset);
 101                                 else
 102                                         glVertexArrayAttribFormat(id, sem, cc, type, true, offset);
 103                                 glVertexArrayAttribBinding(id, sem, binding);
 104                                 glEnableVertexArrayAttrib(id, sem);
 105                         }
 106                         else
 107                         {
 108                                 if(integer)
 109                                         glVertexAttribIPointer(sem, cc, type, stride, reinterpret_cast<void *>(offset));
 110                                 else
 111                                         glVertexAttribPointer(sem, cc, type, true, stride, reinterpret_cast<void *>(offset));
 112                                 if(ARB_instanced_arrays)
 113                                         glVertexAttribDivisor(sem, divisor);
 114                                 glEnableVertexAttribArray(sem);
 115                         }
 116                 }
 117                 offset += get_attribute_size(a);
 118         }
 119
 120         if(!direct)
 121                 glBindBuffer(GL_ARRAY_BUFFER, 0);
 122 }
 123
 124 void OpenGLVertexSetup::unload()
 125 {
 126         if(ARB_direct_state_access)
 127         {
 128                 glVertexArrayVertexBuffer(id, 0, 0, 0, 0);
 129                 glVertexArrayVertexBuffer(id, 1, 0, 0, 0);
 130                 glVertexArrayElementBuffer(id, 0);
 131         }
 132         else
 133         {
 134                 const VertexSetup &self = *static_cast<const VertexSetup *>(this);
 135
 136                 glBindVertexArray(id);
 137                 glBindBuffer(GL_ARRAY_BUFFER, 0);
 138
 139                 for(VertexAttribute a: self.vertex_format)
 140                         if(!is_padding(a))
 141                         {
 142                                 unsigned sem = get_attribute_semantic(a);
 143                                 glDisableVertexAttribArray(sem);
 144                                 glVertexAttribPointer(sem, 1, GL_FLOAT, false, 0, 0);
 145                         }
 146                 for(VertexAttribute a: self.inst_format)
 147                         if(!is_padding(a))
 148                         {
 149                                 unsigned sem = get_attribute_semantic(a);
 150                                 glDisableVertexAttribArray(sem);
 151                                 glVertexAttribPointer(sem, 1, GL_FLOAT, false, 0, 0);
 152                         }
 153
 154                 glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
 155         }
 156 }
 157
 158 void OpenGLVertexSetup::set_debug_name(const string &name)
 159 {
 160 #ifdef DEBUG
 161         if(KHR_debug)
 162                 glObjectLabel(GL_VERTEX_ARRAY, id, name.size(), name.c_str());
 163 #else
 164         (void)name;
 165 #endif
 166 }
 167
 168 } // namespace GL
 169 } // namespace Msp