#include "Texture.hpp"
#include <SDL.h>
#include <SDL_image.h>
#include <easylogging++.h>
bool IsImgInitialized = false;
Texture::Texture(std::string filename, GLenum textureWrapping, GLenum textureFiltering) {
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
//Texture options
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, textureWrapping);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, textureWrapping);
//glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
//Initialize SDL2_image
if (!IsImgInitialized) {
IsImgInitialized = true;
int imgFlags = IMG_INIT_PNG;
if (!(IMG_Init(imgFlags) & imgFlags))
{
throw std::runtime_error("IMG Not initialized: " + std::string(IMG_GetError()));
}
}
//Load image
SDL_Surface *image = IMG_Load(filename.c_str());
if (!image)
throw std::runtime_error("Image not loaded: " + std::string(IMG_GetError()));
if (image->format->BytesPerPixel != 4)
throw std::runtime_error("PNG format is not RGBA");
//Flip surface
SDL_LockSurface(image);
{
int pitch = image->pitch;
int height = image->h;
void* image_pixels = image->pixels;
int index;
void* temp_row;
int height_div_2;
temp_row = (void *)malloc(pitch);
if (!temp_row)
throw std::runtime_error("Not enough memory for texture flipping");
height_div_2 = (int)(height * .5);
for (index = 0; index < height_div_2; index++) {
memcpy((Uint8 *)temp_row,
(Uint8 *)(image_pixels)+
pitch * index,
pitch);
memcpy(
(Uint8 *)(image_pixels)+
pitch * index,
(Uint8 *)(image_pixels)+
pitch * (height - index - 1),
pitch);
memcpy(
(Uint8 *)(image_pixels)+
pitch * (height - index - 1),
temp_row,
pitch);
}
free(temp_row);
}
//Creating texture
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image->w,image->h, 0, GL_RGBA, GL_UNSIGNED_BYTE,
(GLvoid *) image->pixels);
SDL_UnlockSurface(image);
//glGenerateMipmap(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, 0);
SDL_FreeSurface(image);
}
Texture::~Texture() {
glDeleteTextures(1, &texture);
}