Texture.cpp

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#include <iostream>
#include "Texture.h"

using namespace vis2;

Texture::Texture(const std::string& _str_path)
    : image_data_handle(0), texture_handle(0), texture_type(VIS2_TEX_TYPE_RGB), texture_width(0), texture_height(0)
{
    // generate the texture handle
    glGenTextures(1,&texture_handle);
    // bind to a texture unit on the GK
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D,texture_handle);

    // load texture form file
    loadTextureFromFile(_str_path); 

    // copy image data to the GK
    this->texture_width = ilGetInteger(IL_IMAGE_WIDTH);
    this->texture_height = ilGetInteger(IL_IMAGE_HEIGHT);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, ilGetInteger(IL_IMAGE_WIDTH),ilGetInteger(IL_IMAGE_HEIGHT), 0, GL_RGB, GL_UNSIGNED_BYTE,ilGetData());
    
    // set its parameters   
    glGenerateMipmap(GL_TEXTURE_2D);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

}

Texture::Texture(const unsigned int _width, const unsigned int _height, const unsigned int _type)
    : image_data_handle(0), texture_handle(0), texture_type(VIS2_TEX_TYPE_RGB), texture_width(_width), texture_height(_height)
{
    // generate the texture handle
    glGenTextures(1,&texture_handle);
    // bind
    glBindTexture(GL_TEXTURE_2D,texture_handle);

    // define texture format (target, mipmap level, internal format, width, height, border, enum format, type, data)
    switch (_type)
    {
    case VIS2_TEX_TYPE_RGB:
        {
            glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, _width, _height, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
            texture_type = VIS2_TEX_TYPE_RGB;
        }
        break;
    case VIS2_TEX_TYPE_RGBA:
        {
            glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, _width, _height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
            texture_type = VIS2_TEX_TYPE_RGBA;
        }
        break;
    case VIS2_TEX_TYPE_DEPTH:
        {
            // glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, _width, _height, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_BYTE, NULL);
            glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32F, _width, _height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
            texture_type = VIS2_TEX_TYPE_DEPTH;
        }
        break;
    default:
        break;
    }

    // set its parameters   
    glGenerateMipmap(GL_TEXTURE_2D);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); // of vital importance for FBO textures!
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); // of vital importance for FBO textures!
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); // if not set, causes errors on NVIDIA drivers
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); // if not set, causes errors on NVIDIA drivers

}

Texture::~Texture()
{
    if (image_data_handle != 0)
        ilDeleteImages(1,&image_data_handle);
    if (texture_handle != 0)
        glDeleteTextures(1,&texture_handle);
}

void Texture::textureBind(const int _unit)
{
    glActiveTexture(GL_TEXTURE0 + _unit);
    glBindTexture(GL_TEXTURE_2D, texture_handle);
}

void Texture::textureBind2FBO(const int _unit)
{
    // bind texture to FBO (fbo target, fbo attachment, texture target, texture handle, mipmap level)
    switch (this->texture_type)
    {
    case VIS2_TEX_TYPE_RGB:
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + _unit, GL_TEXTURE_2D, this->texture_handle, 0);
        break;
    case VIS2_TEX_TYPE_RGBA:
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + _unit, GL_TEXTURE_2D, this->texture_handle, 0);
        break;
    case VIS2_TEX_TYPE_DEPTH:
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, this->texture_handle, 0);
        break;
    default:
        break;
    }
}

void Texture::loadTextureFromFile(const std::string _file_path)
{
    // uses DevIL
    // generate an image name and bind it
    ilGenImages(1,&image_data_handle);
    ilBindImage(image_data_handle);
    // load image data
    std::cout << "Loading texture from file \"" << _file_path << "\" ." << std::endl;
    if (ilLoadImage((const ILstring)_file_path.c_str()) != IL_TRUE){
        std::cout << "Failed to load texture file \"" << _file_path << "\" !" << std::endl;
        system("PAUSE");
        exit(-1);
    }
    // std::cout << "texture w / h " << ilGetInteger(IL_IMAGE_WIDTH) << " / " << ilGetInteger(IL_IMAGE_HEIGHT) << std::endl; 
}