images.h/images/images.c

#include <stdlib.h>
#include <stdio.h>
#include <limits.h>
#include "images.h"


int image_new(int width, int height, Image* img) {
    //Image img = malloc(sizeof(Image));

    if (img == NULL) return 0;

    img->height = height;
    img->width = width;

    // approximation
    if ((unsigned long int) width * height * 3 > (unsigned long int) UINT_MAX) {
        printf("Image dimensions to large for a bitmap!\n");
        return 0;
    }

    // initialize bitmap...
    img->bitmap = malloc(height * sizeof(char*));
    for (int i = 0; i < height; i++) {
        img->bitmap[i] = malloc(3 * width * sizeof(char));
    }

    //*image = *img;
    return 1;
}

int image_set_px(Image image, int x, int y, int r, int g, int b) {
    if (!image_check_coords(image, x, y)) return 0;

    image.bitmap[y][(3 * x) + 0] = r;
    image.bitmap[y][(3 * x) + 1] = g;
    image.bitmap[y][(3 * x) + 2] = b;

    return 1;
}
int image_set_px_c(Image image, int x, int y, Color color) {
    if (!image_check_coords(image, x, y)) return 0;

    if (color.alpha == 0) return 1;

    if (color.alpha == 1) {
        image.bitmap[y][(3 * x) + 0] = color.r;
        image.bitmap[y][(3 * x) + 1] = color.g;
        image.bitmap[y][(3 * x) + 2] = color.b;
    } else {
        image.bitmap[y][(3 * x) + 0] = (color.alpha * (color.r)) + ((1.0f - color.alpha) * (image.bitmap[y][(3 * x) + 0]));
        image.bitmap[y][(3 * x) + 1] = (color.alpha * (color.g)) + ((1.0f - color.alpha) * (image.bitmap[y][(3 * x) + 1]));
        image.bitmap[y][(3 * x) + 2] = (color.alpha * (color.b)) + ((1.0f - color.alpha) * (image.bitmap[y][(3 * x) + 2]));
    }

    return 1;
}

int image_check_coords(Image image, int x, int y) {
    return x >= 0 && x < image.width && 
           y >= 0 && y < image.height;
}

int image_destroy(Image image) {
    for (int i = 0; i < image.height; i++) {
        free(image.bitmap[i]);
    }
    free(image.bitmap);

    return 1;
}