add rendering algo to fill vbo for color(s) per face (use with any kind of...

add rendering algo to fill vbo for color(s) per face (use with any kind of shader that support position & color

include/Algo/Render/GL2/colorPerFaceRender.h

+/*******************************************************************************
+* CGoGN: Combinatorial and Geometric modeling with Generic N-dimensional Maps  *
+* version 0.1                                                                  *
+* Copyright (C) 2009-2012, IGG Team, LSIIT, University of Strasbourg           *
+*                                                                              *
+* 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.           *
+*                                                                              *
+* Web site: http://cgogn.unistra.fr/                                           *
+* Contact information: cgogn@unistra.fr                                        *
+*                                                                              *
+*******************************************************************************/
+
+#ifndef _COLOR_PER_FACE_RENDER
+#define _COLOR_PER_FACE_RENDER
+
+#include <GL/glew.h>
+
+#include "Topology/generic/dart.h"
+#include "Topology/generic/attributeHandler.h"
+#include "Topology/generic/functor.h"
+#include "Utils/vbo.h"
+#include "Utils/GLSLShader.h"
+
+
+namespace CGoGN
+{
+
+namespace Algo
+{
+
+namespace Render
+{
+
+namespace GL2
+{
+
+/**
+ * Class that allors
+ */
+class ColorPerFaceRender
+{
+protected:
+	Utils::VBO& m_vboPos;
+
+	Utils::VBO& m_vboColors;
+
+	GLuint m_nbTris;
+
+
+public:
+	/**
+	* Constructor
+	*/
+	ColorPerFaceRender() ;
+
+	/**
+	* update drawing buffers
+	* @param map the map
+	* @param positions  attribute of position vertices
+	* @param colorPerFace attribute of color (per face, or per vertex per face)
+	* @param good selector
+	*/
+	template<typename PFP>
+	void updateData(typename PFP::MAP& map, typename PFP::TVEC3& positions, typename PFP::TVEC3& colorPerFace, const FunctorSelect& good = allDarts) ;
+
+	/**
+	 * draw
+	 */
+	void draw(Utils::GLSLShader* sh) ;
+
+};
+
+}//end namespace GL2
+
+}//end namespace Algo
+
+}//end namespace Render
+
+}//end namespace CGoGN
+
+#include "Algo/Render/GL2/colorPerFaceRender.hpp"
+
+#endif

include/Algo/Render/GL2/colorPerFaceRender.hpp

+/*******************************************************************************
+* CGoGN: Combinatorial and Geometric modeling with Generic N-dimensional Maps  *
+* version 0.1                                                                  *
+* Copyright (C) 2009-2012, IGG Team, LSIIT, University of Strasbourg           *
+*                                                                              *
+* 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.           *
+*                                                                              *
+* Web site: http://cgogn.unistra.fr/                                           *
+* Contact information: cgogn@unistra.fr                                        *
+*                                                                              *
+*******************************************************************************/
+#include <cmath>
+
+#include "Geometry/vector_gen.h"
+#include "Topology/generic/dartmarker.h"
+#include "Topology/generic/cellmarker.h"
+#include "Algo/Geometry/centroid.h"
+
+namespace CGoGN
+{
+
+namespace Algo
+{
+
+namespace Render
+{
+
+namespace GL2
+{
+
+
+inline ColorPerFaceRender::ColorPerFaceRender(Utils::VBO& vboPosition, Utils::VBO& vboColor):
+		m_vboPosition(vboPosition), m_vboColor(vboColor), m_nbTris(0)
+{
+}
+
+
+template<typename PFP>
+void ColorPerFaceRender::updateData(typename PFP::MAP& map, typename PFP::TVEC3& positions, typename PFP::TVEC3& colorPerXXX, const FunctorSelect& good)
+{
+	typedef typename PFP::VEC3 VEC3;
+	typedef typename PFP::REAL REAL;
+
+	CellMarker cmv(map,VOLUME);
+	AutoAttributeHandler<VEC3> centerVolumes(map,VOLUME,"centerVolumes");
+	TraversorW<typename PFP::MAP> traVol(map,good);
+	for (Dart d=traVol.begin(); d!=traVol.end(); d=traVol.next())
+	{
+		centerVolumes[d] = Algo::Geometry::volumeCentroid<PFP>(map, d, positions);
+	}
+
+	std::vector<VEC3> buffer;
+	buffer.reserve(16384);
+
+	std::vector<VEC3> bufferColors;
+	bufferColors.reserve(16384);
+
+	TraversorCell<typename PFP::MAP> traFace(map, PFP::MAP::ORBIT_IN_PARENT(FACE),good);
+
+	for (Dart d=traFace.begin(); d!=traFace.end(); d=traFace.next())
+	{
+		Dart a = d;
+		Dart b = map.phi1(a);
+		Dart c = map.phi1(b);
+		// loop to cut a polygon in triangle on the fly (works only with convex faces)
+		do
+		{
+			buffer.push_back(positions[d]);
+			bufferColors.push_back(colorPerXXX[d]);
+			buffer.push_back(positions[b]);
+			bufferColors.push_back(colorPerXXX[b]);
+			buffer.push_back(positions[c]);
+			bufferColors.push_back(colorPerXXX[c]);
+			b = c;
+			c = map.phi1(b);
+		} while (c != d);
+	}
+
+	m_nbTris = buffer.size()/4;
+
+	m_vboPos->allocate(buffer.size());
+	VEC3* ptrPos = reinterpret_cast<VEC3*>(m_vboPos->lockPtr());
+	memcpy(ptrPos,&buffer[0],buffer.size()*sizeof(VEC3));
+	m_vboPos->releasePtr();
+
+	m_vboColors->allocate(bufferColors.size());
+	VEC3* ptrCol = reinterpret_cast<VEC3*>(m_vboColors->lockPtr());
+	memcpy(ptrCol,&bufferColors[0],bufferColors.size()*sizeof(VEC3));
+	m_vboColors->releasePtr();
+
+}
+
+
+void ColorPerFaceRender::draw(Utils::GLSLShader* sh)
+{
+	sh->enableVertexAttribs();
+		glDrawArrays(GL_TRIANGLES , 0 , m_nbTris*3 );
+	sh->disableVertexAttribs();
+}
+
+
+
+
+}//end namespace VBO
+
+}//end namespace Algo
+
+}//end namespace Render
+
+}//end namespace CGoGN