material and texture classes moved to material.(cc,h)
2D texture mappings from textures.cc polished and moved to material.h
add ColourMap class and subclasses to make textures more flexible
two example textures: CheckersTexture and CloudTexture (using Perlin noise)
#ifndef IMAGE_H
#define IMAGE_H
#define IMG_GRAYSCALE 1
#define IMG_RGB 3
/* raw image */
struct image {
int pixel_size; /* should be 1 for grayscale and 3 for RGB*/
int width;
int height;
unsigned char *data;
};
int new_image(struct image **img, int width, int height, int pixelsize);
void destroy_image(struct image **img);
int save_png(const char *fname, struct image *img);
#endif