/* -*- mode: c++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 * ----------------------------------------------------------------------
 * Texture3d.cpp: 3d texture class
 *
 * ======================================================================
 *  AUTHOR:  Wei Qiao <qiaow@purdue.edu>
 *           Purdue Rendering and Perceptualization Lab (PURPL)
 *
 *  Copyright (c) 2004-2013  HUBzero Foundation, LLC
 *
 *  See the file "license.terms" for information on usage and
 *  redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 * ======================================================================
 */
#include <stdio.h>
#include <assert.h>
#include <math.h>

#include "config.h"

#include "Texture3D.h"
#include "Trace.h"

Texture3D::Texture3D() :
    _width(0),
    _height(0),
    _depth(0),
    _numComponents(3),
    _glResourceAllocated(false),
    _id(0),
    _type(GL_FLOAT),
    _interpType(GL_LINEAR),
    _wrapS(GL_CLAMP_TO_EDGE),
    _wrapT(GL_CLAMP_TO_EDGE),
    _wrapR(GL_CLAMP_TO_EDGE)
{}

Texture3D::Texture3D(int width, int height, int depth,
                     GLuint type, GLuint interp,
                     int numComponents, void *data) :
    _width(width),
    _height(height),
    _depth(depth),
    _numComponents(numComponents),
    _glResourceAllocated(false),
    _id(0),
    _type(type),
    _interpType(interp),
    _wrapS(GL_CLAMP_TO_EDGE),
    _wrapT(GL_CLAMP_TO_EDGE),
    _wrapR(GL_CLAMP_TO_EDGE)
{
    if (data != NULL)
        initialize(data);
}

Texture3D::~Texture3D()
{
    glDeleteTextures(1, &_id);
}

GLuint Texture3D::initialize(void *data)
{
    if (_glResourceAllocated)
        glDeleteTextures(1, &_id);

    glGenTextures(1, &_id);

    update(data);

    _glResourceAllocated = true;
    return _id;
}

void Texture3D::update(void *data)
{
#ifdef USE_HALF_FLOAT
    static GLuint halfFloatFormats[] = {
        (GLuint)-1, GL_LUMINANCE16F_ARB, GL_LUMINANCE_ALPHA16F_ARB,
        GL_RGB16F_ARB, GL_RGBA16F_ARB
    };
#elif defined(HAVE_FLOAT_TEXTURES)
    static GLuint floatFormats[] = {
        (GLuint)-1, GL_LUMINANCE32F_ARB, GL_LUMINANCE_ALPHA32F_ARB,
        GL_RGB32F_ARB, GL_RGBA32F_ARB
    };
#endif
    static GLuint basicFormats[] = {
        (GLuint)-1, GL_LUMINANCE, GL_LUMINANCE_ALPHA, GL_RGB, GL_RGBA
    };

    glBindTexture(GL_TEXTURE_3D, _id);

    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

    glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, _wrapS);
    glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, _wrapT);
    glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, _wrapR);

    glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, _interpType);
    glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, _interpType);

    //to do: add handling to more formats
    GLuint *targetFormats;
#ifdef HAVE_FLOAT_TEXTURES
    if (_type == GL_FLOAT) {
# ifdef USE_HALF_FLOAT
        targetFormats = halfFloatFormats;
# else
        targetFormats = floatFormats;
# endif
    } else {
#endif
        targetFormats = basicFormats;
#ifdef HAVE_FLOAT_TEXTURES
    }
#endif

    glTexImage3D(GL_TEXTURE_3D, 0, targetFormats[_numComponents],
                 _width, _height, _depth, 0, 
                 basicFormats[_numComponents], _type, data);

    assert(glGetError()==0);
}

void Texture3D::activate()
{
    glEnable(GL_TEXTURE_3D);
    glBindTexture(GL_TEXTURE_3D, _id);
}

void Texture3D::deactivate()
{
    glDisable(GL_TEXTURE_3D);           
}

void Texture3D::setWrapS(GLuint wrapMode)
{
    _wrapS = wrapMode;
}

void Texture3D::setWrapT(GLuint wrapMode)
{
    _wrapT = wrapMode;
}

void Texture3D::setWrapR(GLuint wrapMode)
{
    _wrapR = wrapMode;
}

void Texture3D::checkMaxSize()
{
    GLint max = 0;
    glGetIntegerv(GL_MAX_3D_TEXTURE_SIZE_EXT, &max);

    TRACE("max 3d texture size: %d", max);
}

void Texture3D::checkMaxUnit()
{
    int max;
    glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &max);

    TRACE("max texture units: %d", max);
}