/***********************************************************************

 * mt4j Copyright (c) 2008 - 2009 C.Ruff, Fraunhofer-Gesellschaft All rights reserved.

 *  

 *   This program is free software: you can redistribute it and/or modify

 *   it under the terms of the GNU General Public License as published by

 *   the Free Software Foundation, either version 3 of the License, or

 *   (at your option) any later version.

 *

 *   This program 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 General Public License for more details.

 *

 *   You should have received a copy of the GNU General Public License

 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

 *

 ***********************************************************************/

package org.mt4j.util.math;



import java.nio.FloatBuffer;



import javax.media.opengl.GL;



import processing.core.PApplet;



import com.sun.opengl.util.BufferUtil;



/**

 * Methods to build VBOs and get their binding names	(Ids).

 * 

 * @author Christopher Ruff

 */

public class ToolsVBO {

	

	//TODO some methods are redundant

	//for floatbuffer vbo updates with vectors (3lements) can be updated the same way i.e.

	

	//////////////////////////////////////////////////////////////

	// 	Methods to build VBOs and get their binding names		//

	//////////////////////////////////////////////////////////////

	/**

	 * Generate vertex vbo.

	 * 

	 * @param pa the pa

	 * @param vertexBuffer the vertex buffer

	 * @param vertexCount the vertex count

	 * 

	 * @return the int

	 */

	public static int generateVertexVBO(PApplet pa, FloatBuffer vertexBuffer, int vertexCount){

		int[] vboVertices = new int[1]; 

		GL gl = Tools3D.getGL(pa);

			gl.glGenBuffers(1, vboVertices, 0);  // Get A Valid Name

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboVertices[0]);  // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER, vertexCount * 3 * BufferUtil.SIZEOF_FLOAT, vertexBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

		return vboVertices[0];

	}

	

	/**

	 * Update vertex vbo.

	 * 

	 * @param pa the pa

	 * @param vertexBuffer the vertex buffer

	 * @param vertexCount the vertex count

	 * @param vboName the vbo name

	 */

	public static void updateVertexVBO(PApplet pa, FloatBuffer vertexBuffer, int vertexCount, int vboName){

		GL gl = Tools3D.getGL(pa);

		gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboName);  // Bind The Buffer

		// Load The Data

		gl.glBufferData(GL.GL_ARRAY_BUFFER, vertexCount * 3 * BufferUtil.SIZEOF_FLOAT, vertexBuffer, GL.GL_STATIC_DRAW);

		//Unbind VBOs 

		gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

		gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

	}

	

	/**

	 * Generate texture vbo.

	 * 

	 * @param pa the pa

	 * @param textureBuffer the texture buffer

	 * @param vertexCount the vertex count

	 * 

	 * @return the int

	 */

	public static int generateTextureVBO(PApplet pa, FloatBuffer textureBuffer, int vertexCount){

		int[] vboTexCoords = new int[1];// Texture Coordinate VBO Name

		GL gl = Tools3D.getGL(pa);

			gl.glGenBuffers(1, vboTexCoords, 0);  // Get A Valid Name

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboTexCoords[0]); // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER, vertexCount * 2 * BufferUtil.SIZEOF_FLOAT, textureBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

		return vboTexCoords[0];

	}

	

	/**

	 * Update texture vbo.

	 * 

	 * @param pa the pa

	 * @param textureBuffer the texture buffer

	 * @param vertexCount the vertex count

	 * @param vboName the vbo name

	 */

	public static void updateTextureVBO(PApplet pa, FloatBuffer textureBuffer, int vertexCount, int vboName){

		GL gl = Tools3D.getGL(pa);

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboName); // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER, vertexCount * 2 * BufferUtil.SIZEOF_FLOAT, textureBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

	}

	

	/**

	 * Generate color vbo.

	 * 

	 * @param pa the pa

	 * @param colorBuffer the color buffer

	 * @param vertexCount the vertex count

	 * 

	 * @return the int

	 */

	public static int generateColorVBO(PApplet pa, FloatBuffer colorBuffer, int vertexCount){

		int[] vboColor = new int[1];// vertexcolor Coordinate VBO Name

		GL gl = Tools3D.getGL(pa);

			gl.glGenBuffers(1, vboColor, 0);  // Get A Valid Name

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboColor[0]); // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER, vertexCount * 4 * BufferUtil.SIZEOF_FLOAT, colorBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

		return vboColor[0];

	}

	

	/**

	 * Update color vbo.

	 * 

	 * @param pa the pa

	 * @param colorBuffer the color buffer

	 * @param vertexCount the vertex count

	 * @param vboName the vbo name

	 */

	public static void updateColorVBO(PApplet pa, FloatBuffer colorBuffer, int vertexCount, int vboName){

		GL gl = Tools3D.getGL(pa);

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboName); // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER, vertexCount * 4 * BufferUtil.SIZEOF_FLOAT, colorBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

	}

	

	/**

	 * Generate stroke color vbo.

	 * 

	 * @param pa the pa

	 * @param strokeColBuffer the stroke col buffer

	 * @param vertexCount the vertex count

	 * 

	 * @return the int

	 */

	public static int generateStrokeColorVBO(PApplet pa, FloatBuffer strokeColBuffer, int vertexCount){

		int[] vboStrokeColor = new int[1];// stroke Coordinate VBO Name

		GL gl = Tools3D.getGL(pa);

			gl.glGenBuffers(1, vboStrokeColor, 0);  // Get A Valid Name

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboStrokeColor[0]); // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER,vertexCount * 4 * BufferUtil.SIZEOF_FLOAT, strokeColBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

		return vboStrokeColor[0];

	}

	

	/**

	 * Update stroke color vbo.

	 * 

	 * @param pa the pa

	 * @param strokeColBuffer the stroke col buffer

	 * @param vertexCount the vertex count

	 * @param vboName the vbo name

	 */

	public static void updateStrokeColorVBO(PApplet pa, FloatBuffer strokeColBuffer, int vertexCount, int vboName){

		GL gl = Tools3D.getGL(pa);

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboName); // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER,vertexCount * 4 * BufferUtil.SIZEOF_FLOAT, strokeColBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

	}

	

	

	/**

	 * Generate normals vbo.

	 * 

	 * @param pa the pa

	 * @param normalsBuffer the normals buffer

	 * @param normalsCount the normals count

	 * 

	 * @return the int

	 */

	public static int generateNormalsVBO(PApplet pa, FloatBuffer normalsBuffer, int normalsCount){

		int[] vboNormals = new int[1]; 

		GL gl = Tools3D.getGL(pa);

			gl.glGenBuffers(1, vboNormals, 0);  // Get A Valid Name

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboNormals[0]);  // Bind The Buffer

			// Load The Data

			gl.glBufferData(GL.GL_ARRAY_BUFFER, normalsCount * 3 * BufferUtil.SIZEOF_FLOAT, normalsBuffer, GL.GL_STATIC_DRAW);

			//Unbind VBOs 

			gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

			gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

		return vboNormals[0];

	}

	

	

	/**

	 * Update normals vbo.

	 * 

	 * @param pa the pa

	 * @param normalsBuffer the normals buffer

	 * @param normalsCount the normals count

	 * @param vboName the vbo name

	 */

	public static void updateNormalsVBO(PApplet pa, FloatBuffer normalsBuffer, int normalsCount, int vboName){

		GL gl = Tools3D.getGL(pa);

		gl.glBindBuffer(GL.GL_ARRAY_BUFFER, vboName);  // Bind The Buffer

		// Load The Data

		gl.glBufferData(GL.GL_ARRAY_BUFFER, normalsCount * 3 * BufferUtil.SIZEOF_FLOAT, normalsBuffer, GL.GL_STATIC_DRAW);

		//Unbind VBOs 

		gl.glBindBuffer(GL.GL_ARRAY_BUFFER, 0);

		gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, 0);

	}



}