Initial support for instanced rendering

[libs/gl.git] / source / vertexsetup.cpp

diff --git a/source/vertexsetup.cpp b/source/vertexsetup.cpp
index f6a71f4996162b9addaa3b337c6a5ea35121e1be..8465ab060d54fe77041106a2c3c67a342102116e 100644 (file)
--- a/source/vertexsetup.cpp
+++ b/source/vertexsetup.cpp
@@ -1,4 +1,8 @@
+#include <msp/core/raii.h>
+#include <msp/gl/extensions/arb_direct_state_access.h>
+#include <msp/gl/extensions/arb_instanced_arrays.h>
 #include <msp/gl/extensions/arb_vertex_array_object.h>
+#include <msp/gl/extensions/arb_vertex_attrib_binding.h>
 #include <msp/gl/extensions/arb_vertex_buffer_object.h>
 #include <msp/gl/extensions/arb_vertex_shader.h>
 #include "buffer.h"
@@ -10,12 +14,16 @@ namespace Msp {
 namespace GL {
 
 VertexSetup::VertexSetup():
-       dirty(false),
-       array(0),
+       dirty(0),
+       vertex_array(0),
+       inst_array(0),
        index_buffer(0)
 {
        static Require req(ARB_vertex_array_object);
-       glGenVertexArrays(1, &id);
+       if(ARB_direct_state_access)
+               glCreateVertexArrays(1, &id);
+       else
+               glGenVertexArrays(1, &id);
 }
 
 VertexSetup::~VertexSetup()
@@ -27,44 +35,91 @@ VertexSetup::~VertexSetup()
 
 void VertexSetup::set_vertex_array(const VertexArray &a)
 {
-       array = &a;
-       update();
+       vertex_array = &a;
+       update(VERTEX_ARRAY);
+}
+
+void VertexSetup::set_instance_array(const VertexArray *a)
+{
+       if(a)
+               static Require req(ARB_instanced_arrays);
+
+       inst_array = a;
+       update(INSTANCE_ARRAY);
 }
 
 void VertexSetup::set_index_buffer(const Buffer &ibuf)
 {
        index_buffer = &ibuf;
-       update();
+       update(INDEX_BUFFER);
 }
 
-void VertexSetup::update() const
+void VertexSetup::update(unsigned mask) const
 {
-       if(current()!=this)
+       static bool direct = ARB_direct_state_access && ARB_vertex_attrib_binding;
+       if(!direct && current()!=this)
        {
-               dirty = true;
+               dirty |= mask;
                return;
        }
 
-       Bind bind_vbuf(array->get_buffer(), ARRAY_BUFFER);
+       if(mask&VERTEX_ARRAY)
+               update_vertex_array(*vertex_array, 0, 0, direct);
+
+       if(mask&INSTANCE_ARRAY)
+       {
+               if(inst_array)
+                       update_vertex_array(*inst_array, 1, 1, direct);
+       }
+
+       if(mask&INDEX_BUFFER)
+       {
+               if(direct)
+                       glVertexArrayElementBuffer(id, index_buffer->get_id());
+               else
+                       glBindBuffer(ELEMENT_ARRAY_BUFFER, index_buffer->get_id());
+       }
+}
+
+void VertexSetup::update_vertex_array(const VertexArray &array, unsigned binding, unsigned divisor, bool direct) const
+{
+       Conditional<Bind> bind_vbuf(!direct, array.get_buffer(), ARRAY_BUFFER);
 
-       const VertexFormat &fmt = array->get_format();
+       const VertexFormat &fmt = array.get_format();
        unsigned stride = get_stride(fmt)*sizeof(float);
-       float *ptr = 0;
+       if(direct)
+       {
+               glVertexArrayVertexBuffer(id, binding, array.get_buffer()->get_id(), 0, stride);
+               glVertexArrayBindingDivisor(id, binding, divisor);
+       }
+
+       unsigned offset = 0;
        for(const unsigned char *c=fmt.begin(); c!=fmt.end(); ++c)
        {
                unsigned t = get_component_type(*c);
                if(t>=get_component_type(ATTRIB1))
                        t -= get_component_type(ATTRIB1);
                unsigned sz = get_component_size(*c);
-               if(*c==COLOR4_UBYTE)
-                       glVertexAttribPointer(t, 4, GL_UNSIGNED_BYTE, true, stride, ptr);
+               if(direct)
+               {
+                       if(*c==COLOR4_UBYTE)
+                               glVertexArrayAttribFormat(id, t, 4, GL_UNSIGNED_BYTE, true, offset);
+                       else
+                               glVertexArrayAttribFormat(id, t, sz, GL_FLOAT, false, offset);
+                       glVertexArrayAttribBinding(id, t, binding);
+                       glEnableVertexArrayAttrib(id, t);
+               }
                else
-                       glVertexAttribPointer(t, sz, GL_FLOAT, false, stride, ptr);
-               glEnableVertexAttribArray(t);
-               ptr += sz;
+               {
+                       if(*c==COLOR4_UBYTE)
+                               glVertexAttribPointer(t, 4, GL_UNSIGNED_BYTE, true, stride, reinterpret_cast<unsigned char *>(offset));
+                       else
+                               glVertexAttribPointer(t, sz, GL_FLOAT, false, stride, reinterpret_cast<float *>(offset));
+                       glVertexAttribDivisor(t, divisor);
+                       glEnableVertexAttribArray(t);
+               }
+               offset += sz*sizeof(float);
        }
-
-       glBindBuffer(ELEMENT_ARRAY_BUFFER, index_buffer->get_id());
 }
 
 void VertexSetup::bind() const
@@ -74,8 +129,8 @@ void VertexSetup::bind() const
                glBindVertexArray(id);
                if(dirty)
                {
-                       update();
-                       dirty = false;
+                       update(dirty);
+                       dirty = 0;
                }
        }
 }