Initial support for instanced rendering

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

diff --git a/source/batch.cpp b/source/batch.cpp
index 89b8f48f4d44920d4b63a3829a44f81f9c2f44e8..af1d243e6cba1551e6be65255a55e69a4e7029cf 100644 (file)
--- a/source/batch.cpp
+++ b/source/batch.cpp
@@ -1,3 +1,4 @@
+#include <msp/gl/extensions/arb_draw_instanced.h>
 #include <msp/gl/extensions/ext_draw_range_elements.h>
 #include <msp/gl/extensions/msp_legacy_features.h>
 #include <msp/gl/extensions/msp_primitive_restart.h>
@@ -225,6 +226,27 @@ unsigned Batch::get_index(unsigned i) const
 }
 
 void Batch::draw() const
+{
+       BindRestore _bind_ibuf(get_buffer(), ELEMENT_ARRAY_BUFFER);
+       const void *data_ptr = setup_draw();
+
+       if(EXT_draw_range_elements)
+               glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, data_ptr);
+       else
+               glDrawElements(prim_type, size(), data_type, data_ptr);
+}
+
+void Batch::draw_instanced(unsigned count) const
+{
+       static Require req(ARB_draw_instanced);
+
+       BindRestore _bind_ibuf(get_buffer(), ELEMENT_ARRAY_BUFFER);
+       const void *data_ptr = setup_draw();
+
+       glDrawElementsInstanced(prim_type, size(), data_type, data_ptr, count);
+}
+
+const void *Batch::setup_draw() const
 {
        if(restart)
        {
@@ -242,23 +264,15 @@ void Batch::draw() const
        else if(restart_index && restart_index<=max_index)
                set_restart_index(0);
 
-       Buffer *ibuf = get_buffer();
-       const void *data_ptr;
-       BindRestore _bind_ibuf(ibuf, ELEMENT_ARRAY_BUFFER);
-       if(ibuf)
+       if(get_buffer())
        {
                if(dirty)
                        update_buffer();
 
-               data_ptr = reinterpret_cast<const void *>(get_offset());
+               return reinterpret_cast<const void *>(get_offset());
        }
        else
-               data_ptr = &data[0];
-
-       if(EXT_draw_range_elements)
-               glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, data_ptr);
-       else
-               glDrawElements(prim_type, size(), data_type, data_ptr);
+               return &data[0];
 }
 
 void Batch::set_restart_index(unsigned index)