/* -*- mode: c++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 * Copyright (c) 2004-2013  HUBzero Foundation, LLC
 *
 */
#ifndef NV_HEIGHTMAP_H
#define NV_HEIGHTMAP_H

#include <graphics/Geometry.h>
#include <graphics/RenderContext.h>
#include <vrmath/Vector3f.h>

#include "TransferFunction.h"
#include "Shader.h"
#include "AxisRange.h"

namespace nv {

class Grid;

/**
 *@brief Create a surface from height map and line contour of the generated surface
 */
class HeightMap
{
public:
    HeightMap();

    ~HeightMap();

    void render(nv::graphics::RenderContext *renderContext);

    /**
     *@brief Create a height map with height values
     *@param startX x position of the first height value
     *@param startY y position of the first height value
     *@param endX x position of the last height value
     *@param endY y position of the last height value
     *@param xCount the number of columns of height values
     *@param yCount the number of rows of height values
     *@param height a pointer value adrressing xCount * yCount values of heights
     */
    void setHeight(float startX, float startY, float endX, float endY,
                   int xCount, int yCount, float *height);
#if 0
    /**
     *@brief Create a height map with a set of points
     *@param xCount the number of columns of height values
     *@param yCount the number of rows of height values
     */
    void setHeight(int xCount, int yCount, vrmath::Vector3f *heights);
#endif
    void mapToGrid(Grid *grid);

    /**
     *@brief Define a color map for color shading of heightmap
     */
    void transferFunction(TransferFunction *transferFunc)
    {
        _transferFunc = transferFunc;
    }

    /**
     *@brief Get the color map defined for shading of this heightmap
     */
    TransferFunction *transferFunction()
    {
        return _transferFunc;
    }

    /**
     *@brief Set the visibility of the height map
     */
    void setVisible(bool visible)
    {
        _visible = visible;
    }

    /**
     *@brief Return the status of the visibility
     */
    bool isVisible() const
    {
        return _visible;
    }

    /**
     *@brief Set the visibility of the line contour
     */
    void setLineContourVisible(bool visible)
    {
        _contourVisible = visible;
    }

    void opacity(float opacity)
    {
        _opacity = opacity;
    }

    float opacity()
    {
        return _opacity;
    }

    /**
     *@brief Defind the color of the line contour
     */
    void setLineContourColor(float *rgb)
    {
        _contourColor.x = rgb[0];
        _contourColor.y = rgb[1];
        _contourColor.z = rgb[2];
    }

    void getBounds(vrmath::Vector3f& bboxMin, vrmath::Vector3f& bboxMax) const;

    AxisRange xAxis, yAxis, zAxis, wAxis;
    static bool updatePending;
    static double valueMin, valueMax;

private:
    void createIndexBuffer(int xCount, int zCount, float *heights);
    vrmath::Vector3f *createHeightVertices(float startX, float startY,
                                           float endX, float endY,
                                           int xCount, int yCount, float *height);
    void reset();

    unsigned int _vertexBufferObjectID;
    unsigned int _texcoordBufferObjectID;
    int _vertexCount;
    nv::graphics::Geometry *_contour;
    TransferFunction *_transferFunc;
    float _opacity;
    Shader *_shader;
    int *_indexBuffer;
    int _indexCount;
    vrmath::Vector3f _contourColor;

    bool _contourVisible;
    bool _visible;

    vrmath::Vector3f _scale;
    vrmath::Vector3f _centerPoint;
    int _xNum, _yNum;          // Number of elements x and y axes in grid.
    float *_heights;           // Array of original (unscaled) heights
                               // (y-values)
};

}

#endif