/*******************************************************
 * Copyright (c) 2015-2019, ArrayFire
 * All rights reserved.
 *
 * This file is distributed under 3-clause BSD license.
 * The complete license agreement can be obtained at:
 * http://arrayfire.com/licenses/BSD-3-Clause
 ********************************************************/

#include <forge.h>
#define USE_FORGE_CPU_COPY_HELPERS
#include <ComputeCopy.h>
#include <complex>
#include <cmath>
#include <vector>
#include <iostream>

const unsigned DIMX = 640;
const unsigned DIMY = 480;
const float PI = 3.14159265359f;
const float MINIMUM = 1.0f;
const float MAXIMUM = 20.f;
const float STEP    = 2.0f;
const int NELEMS    = (int)((MAXIMUM-MINIMUM+1)/STEP);

using namespace std;

void generateColors(std::vector<float>& colors)
{
    static const float AF_BLUE[] = {0.0588f , 0.1137f , 0.2745f , 1.0f};
    static const float AF_ORANGE[] = {0.8588f , 0.6137f , 0.0745f , 1.0f};

    int numElems = NELEMS*NELEMS*NELEMS;
    colors.clear();
    for (int i=0; i<numElems; ++i) {
        if ((i%2) == 0) {
            colors.push_back(AF_ORANGE[0]);
            colors.push_back(AF_ORANGE[1]);
            colors.push_back(AF_ORANGE[2]);
        } else {
            colors.push_back(AF_BLUE[0]);
            colors.push_back(AF_BLUE[1]);
            colors.push_back(AF_BLUE[2]);
        }
    }
}

void generatePoints(std::vector<float> &points, std::vector<float> &dirs)
{
    points.clear();

    for (int k=0; k<NELEMS; ++k) {
        float z = MINIMUM + k*STEP;
        for (int j=0; j<NELEMS; ++j) {
            float y = MINIMUM + j*STEP;
            for (int i=0; i<NELEMS; ++i) {
                float x = MINIMUM + i*STEP;
                points.push_back(x);
                points.push_back(y);
                points.push_back(z);
                dirs.push_back(x-10.0f);
                dirs.push_back(y-10.0f);
                dirs.push_back(z-10.0f);
            }
        }
    }
}

int main(void)
{
    /*
     * First Forge call should be a window creation call
     * so that necessary OpenGL context is created for any
     * other forge::* object to be created successfully
     */
    forge::Window wnd(DIMX, DIMY, "3D Vector Field Demo");
    wnd.makeCurrent();

    forge::Chart chart(FG_CHART_3D);
    chart.setAxesLimits(MINIMUM-1.0f, MAXIMUM,
                        MINIMUM-1.0f, MAXIMUM,
                        MINIMUM-1.0f, MAXIMUM);
    chart.setAxesTitles("x-axis", "y-axis", "z-axis");

    int numElems = NELEMS*NELEMS*NELEMS;
    forge::VectorField field = chart.vectorField(numElems, forge::f32);
    field.setColor(0.f, 1.f, 0.f, 1.f);

    std::vector<float> points;
    std::vector<float> colors;
    std::vector<float> dirs;
    generatePoints(points, dirs);
    generateColors(colors);

    GfxHandle* handles[3];
    createGLBuffer(&handles[0], field.vertices(), FORGE_VERTEX_BUFFER);
    createGLBuffer(&handles[1], field.colors(), FORGE_VERTEX_BUFFER);
    createGLBuffer(&handles[2], field.directions(), FORGE_VERTEX_BUFFER);

    copyToGLBuffer(handles[0], (ComputeResourceHandle)points.data(),   field.verticesSize());
    copyToGLBuffer(handles[1], (ComputeResourceHandle)colors.data(),     field.colorsSize());
    copyToGLBuffer(handles[2], (ComputeResourceHandle)dirs.data()  , field.directionsSize());

    do {
        wnd.draw(chart);
    } while(!wnd.close());

    releaseGLBuffer(handles[0]);
    releaseGLBuffer(handles[1]);
    releaseGLBuffer(handles[2]);

    return 0;
}
