ImageHandler.cpp

#include <iostream>
#include <GL/glut.h>

class Image
{
  public:
    int width;
    int height;
    unsigned char *data;
    void readBMP(char* filename);
    GLint toTexture();
};
void Image::readBMP(char* filename)
{
    int i;
    FILE* f = fopen(filename, "rb");
    unsigned char info[54];
    fread(info, sizeof(unsigned char), 54, f); // read the 54-byte header

    // extract image height and width from header
    width = *(int*)&info[18];
    height = *(int*)&info[22];

    int size = 3 * width * height;
    data = new unsigned char[size]; // allocate 3 bytes per pixel
    fread(data, sizeof(unsigned char), size, f); // read the rest of the data at once
    fclose(f);

    for(i = 0; i < size; i += 3)
    {
            unsigned char tmp = data[i];
            data[i] = data[i+2];
            data[i+2] = tmp;
    }

    width = width;
    height = height;
}