for(unsigned i=0; i<2; ++i)
target[i] = new RenderTarget(w, h, (RENDER_COLOR,RGB16F));
for(unsigned i=0; i<2; ++i)
target[i] = new RenderTarget(w, h, (RENDER_COLOR,RGB16F));
common_shdata.uniform("source", 0);
common_shdata.uniform("blurred", 1);
common_shdata.uniform("source", 0);
common_shdata.uniform("blurred", 1);