// Sh: A GPU metaprogramming language.//// Copyright 2003-2005 Serious Hack Inc.// // This library is free software; you can redistribute it and/or// modify it under the terms of the GNU Lesser General Public// License as published by the Free Software Foundation; either// version 2.1 of the License, or (at your option) any later version.//// This library is distributed in the hope that it will be useful,// but WITHOUT ANY WARRANTY; without even the implied warranty of// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU// Lesser General Public License for more details.//// You should have received a copy of the GNU Lesser General Public// License along with this library; if not, write to the Free Software// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, // MA  02110-1301, USA//////////////////////////////////////////////////////////////////////////////#include <sh/sh.hpp>#include <sh/shutil.hpp>#include <iostream>#include "Shader.hpp"#include "Globals.hpp"using namespace SH;using namespace ShUtil;class FragmentLooping : public Shader {public:  FragmentLooping();  ~FragmentLooping();  bool init();  ShProgram vertex() { return vsh;}  ShProgram fragment() { return fsh;}  ShProgram vsh, fsh;  static FragmentLooping instance;};FragmentLooping::FragmentLooping()  : Shader("Branching: Loops in Fragment Unit"){}FragmentLooping::~FragmentLooping(){}bool FragmentLooping::init(){  vsh = ShKernelLib::shVsh( Globals::mv, Globals::mvp );  vsh = vsh << shExtract("lightPos") << Globals::lightPos;   vsh = shSwizzle("texcoord", "posh") << vsh;    ShColor3f SH_DECL(diffuse) = ShColor3f(1.0, 0.0, 0.0);  ShAttrib1f SH_DECL(julia_max_iter) = 20.0;  julia_max_iter.range(1.0, 40.0);  ShAttrib2f SH_DECL(julia_c) = ShAttrib2f(0.54, -0.51);  julia_c.range(-1.0, 1.0);  ShAttrib1f SH_DECL(brightness) = 1.0;  brightness.range(0.0, 10.0);  ShAttrib1f SH_DECL(height) = 0.2;  height.range(0.0, 4.0);  ShAttrib1f SH_DECL(zoom) = 0.33;  zoom.range(0.0, 10.0);  ShPoint2f SH_DECL(centre) = ShPoint2f(0.0, 0.0);  centre.range(-2.0, 2.0);    ShAttrib1f SH_DECL(gamma) = 0.7;  gamma.range(0.0, 1.0);    fsh = SH_BEGIN_PROGRAM("gpu:fragment") {    ShInputTexCoord2f u;        ShOutputColor3f ocol; // Color of result    u = u - centre;    u /= zoom;        ShAttrib1f i = 0.0;     SH_DO {      ShTexCoord2f v;      v(0) = u(0)*u(0) - u(1)*u(1);      v(1) = 2.0 * u(0) * u(1);      u = v + julia_c;      i += 1.0;    } SH_UNTIL (0 == ((dot(u, u) < 2.0) * (i < julia_max_iter)));    ShAttrib1f disp = pow(i / julia_max_iter, gamma);    ocol = disp * diffuse * brightness;  } SH_END;    return true;}FragmentLooping FragmentLooping::instance = FragmentLooping();