Add the uniform buffer type

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

diff --git a/source/buffer.cpp b/source/buffer.cpp
index 1762b20482eaa45944d94529b7c044aa25c898b5..f09268741fc7705e69432c6ee18e5f03edb069ec 100644 (file)
--- a/source/buffer.cpp
+++ b/source/buffer.cpp
@@ -1,14 +1,16 @@
 #include <stdexcept>
+#include "arb_uniform_buffer_object.h"
 #include "arb_vertex_buffer_object.h"
-#include "extension.h"
 #include "buffer.h"
+#include "extension.h"
+#include "misc.h"
 
 using namespace std;
 
 namespace Msp {
 namespace GL {
 
-const Buffer *Buffer::bound[4] = { 0, 0, 0, 0 };
+const Buffer *Buffer::bound[5] = { 0, 0, 0, 0, 0 };
 
 Buffer::Buffer(BufferType t):
        type(t),
@@ -30,6 +32,8 @@ void Buffer::require_buffer_type(BufferType type)
        static RequireExtension _req_vbo("GL_ARB_vertex_buffer_object");
        if(type==PIXEL_PACK_BUFFER || type==PIXEL_UNPACK_BUFFER)
                static RequireExtension _req_pbo("GL_ARB_pixel_buffer_object");
+       else if(type==UNIFORM_BUFFER)
+               static RequireExtension _req_ubo("GL_ARB_uniform_buffer_object");
 }
 
 void Buffer::set_usage(BufferUsage u)
@@ -54,6 +58,11 @@ void Buffer::sub_data(unsigned off, unsigned sz, const void *d)
        restore(old, type);
 }
 
+BufferRange *Buffer::create_range(unsigned s, unsigned o)
+{
+       return new BufferRange(*this, s, o);
+}
+
 void Buffer::bind_to(BufferType t) const
 {
        if(t!=type)
@@ -76,6 +85,7 @@ const Buffer *&Buffer::binding(BufferType type)
        case ELEMENT_ARRAY_BUFFER: return bound[1];
        case PIXEL_PACK_BUFFER:    return bound[2];
        case PIXEL_UNPACK_BUFFER:  return bound[3];
+       case UNIFORM_BUFFER:       return bound[4];
        default: throw invalid_argument("Buffer::binding");
        }
 }
@@ -101,5 +111,70 @@ void Buffer::restore(const Buffer *buf, BufferType type)
        }
 }
 
+
+vector<const BufferRange *> BufferRange::bound_uniform;
+
+BufferRange::BufferRange(Buffer &b, unsigned o, unsigned s):
+       buffer(b),
+       offset(o),
+       size(s)
+{
+       if(o>buffer.get_size() || o+s>buffer.get_size())
+               throw out_of_range("BufferRange::BufferRange");
+}
+
+void BufferRange::data(const void *d)
+{
+       buffer.sub_data(offset, size, d);
+}
+
+void BufferRange::bind_to(BufferType t, unsigned i)
+{
+       if(t!=buffer.type)
+               Buffer::require_buffer_type(t);
+       // Intentionally using bitwise | to avoid short-circuiting
+       if(Buffer::set_current(t, &buffer) | set_current(t, i, this))
+               glBindBufferRange(t, i, buffer.id, offset, size);
+}
+
+void BufferRange::unbind_from(BufferType t, unsigned i)
+{
+       if(set_current(t, i, 0))
+       {
+               Buffer::set_current(t, 0);
+               glBindBufferBase(t, i, 0);
+       }
+}
+
+const BufferRange *&BufferRange::binding(BufferType type, unsigned index)
+{
+       if(type==UNIFORM_BUFFER)
+       {
+               if(index>=get_n_uniform_buffer_bindings())
+                       throw out_of_range("Buffer::binding");
+               if(bound_uniform.size()<=index)
+                       bound_uniform.resize(index+1);
+               return bound_uniform[index];
+       }
+       else
+               throw invalid_argument("Buffer::binding");
+}
+
+bool BufferRange::set_current(BufferType type, unsigned index, const BufferRange *buf)
+{
+       const BufferRange *&ptr = binding(type, index);
+       if(ptr==buf)
+               return false;
+
+       ptr = buf;
+       return true;
+}
+
+unsigned BufferRange::get_n_uniform_buffer_bindings()
+{
+       static unsigned count = get_i(GL_MAX_UNIFORM_BUFFER_BINDINGS);
+       return count;
+}
+
 } // namespace GL
 } // namespace Msp