e current block (CUDA) or work group (GLSL)</td></tr>
<tr><td><tt class="docutils literal"><span class="pre"><span class="Identifier">threadIdx</span></span></tt></td><td><tt class="docutils literal"><span class="pre"><span class="Identifier">gl_LocalInvocationID</span></span></tt></td><td>The index of the current thread within its block (CUDA) or work group (GLSL)</td></tr>
<tr><td><tt class="docutils literal"><span class="pre"><span class="Identifier">blockIdx</span> <span class="Operator">*</span> <span 