From Wang Rui, "In the attached files I've added the Compute Shader support for OSG, as well as serializer updates and a new osgcomputeshaders example. My submission also include a setComputeGroups() function in Program for setting compute-shader work groups, and a bindToImageUnit() function in Texture for binding textures as image variables in shaders.

All code are tested on Windows 7 + NVIDIA GFX 570 with the latest GeForce 310.70 Driver (BETA), which could support OpenGL 4.3.

Compute shader information can be found at "http://www.opengl.org/registry/specs/ARB/compute_shader.txt"
"

src/osg/GL2Extensions.cpp

@@ -214,6 +214,9 @@ GL2Extensions::GL2Extensions(const GL2Extensions& rhs) : osg::Referenced()
 
     // ARB_shader_atomic_counters
     _glGetActiveAtomicCounterBufferiv = rhs._glGetActiveAtomicCounterBufferiv;
+
+    // ARB_compute_shader
+    _glDispatchCompute = rhs._glDispatchCompute;
 }
 
 
@@ -399,6 +402,9 @@ void GL2Extensions::lowestCommonDenominator(const GL2Extensions& rhs)
 
     // ARB_shader_atomic_counters
     if(!rhs._glGetActiveAtomicCounterBufferiv) _glGetActiveAtomicCounterBufferiv = 0;
+
+    // ARB_compute_shder
+    if(!rhs._glDispatchCompute) _glDispatchCompute = 0;
 }
 
 
@@ -589,6 +595,9 @@ void GL2Extensions::setupGL2Extensions(unsigned int contextID)
         // ARB_shader_atomic_counters
         _glGetActiveAtomicCounterBufferiv= 0;
 
+        // ARB_compute_shader
+        _glDispatchCompute= 0;
+
         return;
     }
 
@@ -794,6 +803,9 @@ void GL2Extensions::setupGL2Extensions(unsigned int contextID)
 
     // ARB_shader_atomic_counters
     setGLExtensionFuncPtr(_glGetActiveAtomicCounterBufferiv,  "glGetActiveAtomicCounterBufferiv" );
+
+    // ARB_compute_shader
+    setGLExtensionFuncPtr(_glDispatchCompute,  "glDispatchCompute" );
 }
 
 
@@ -2826,6 +2838,18 @@ void GL2Extensions::glGetActiveAtomicCounterBufferiv( GLuint program, GLuint buf
     }
 }
 
+void GL2Extensions::glDispatchCompute( GLuint numGroupsX, GLuint numGroupsY, GLuint numGroupsZ ) const
+{
+    if (_glDispatchCompute)
+    {
+        _glDispatchCompute( numGroupsX, numGroupsY, numGroupsZ );
+    }
+    else
+    {
+        NotSupported( "glDispatchCompute" );
+    }
+}
+
 ///////////////////////////////////////////////////////////////////////////
 // C++-friendly convenience methods