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#include <Imlib2.h>
#include <time.h>
#include <stdlib.h>
#include <stdint.h>

typedef uint32_t Color;

int abs(int n)
{
    return (n > 0 ? n : -n);
}

int sign(int n)
{
    return (n == 0 ? 0 : (n > 0 ? 1 : -1));
}

Color blend_add(Color u, Color v)
{
    int r = ((u >> 16) & 0xFF) + ((v >> 16) & 0xFF);
    int g = ((u >> 8 ) & 0xFF) + ((v >> 8 ) & 0xFF);
    int b = ((u      ) & 0xFF) + ((v      ) & 0xFF);

    r = (r > 0xFF ? 0xFF : r);
    g = (g > 0xFF ? 0xFF : g);
    b = (b > 0xFF ? 0xFF : b);

    return (Color)((0xFF << 24) | (r << 16) | (g << 8) | b);
}

Color blend_mix(Color u, Color v, int i)
{
    int r = ((u >> 16) & 0xFF) * (255-i) / 255 + ((v >> 16) & 0xFF) * i / 255;
    int g = ((u >> 8 ) & 0xFF) * (255-i) / 255 + ((v >> 8 ) & 0xFF) * i / 255;
    int b = ((u      ) & 0xFF) * (255-i) / 255 + ((v      ) & 0xFF) * i / 255;

    return (Color)((0xFF << 24) | (r << 16) | (g << 8) | b);
}

void put(Color *tex, int w, int h, int x, int y, Color c)
{
    if (x < 0 || x >= w || y < 0 || y >= h)
        return;

    tex[y*w+x] = blend_add(tex[y*w+x], c);
}

void gradient(Color *tex, int w, int h, Color a, Color b)
{
    int i, j;

    for (i=0; i<h; i++)
    {
        for (j=0; j<w; j++)
        {
            put(tex, w, h, j, i, blend_mix(a, b, i*255/h));
        }
    }
}

void random_noise(Color *tex, int w, int h, Color c, int n)
{
    int i;

    for (i=0; i<n; i++)
    {
        int x = rand() % w;
        int y = rand() % h;

        put(tex, w, h, x, y, c);
    }
}

// ****
// ####****
// ########****
//    #########****
//       ##########****

void tape(Color *tex, int w, int h, Color c, int y, int l, int r)
{
    int i, j, k;

    for (i=0; i<h; i++)
    {
        for (j=(i-l+1)*abs(r); j<i*abs(r); j++)
        {
            put(tex, w, h, j, y+i*sign(r), c);
        }
    }
}

void draw(Color *tex, int w, int h)
{
    random_noise(tex, w, h, 0xAAFFAA, 424242);
    random_noise(tex, w, h, 0xBCABAD, 242424);

    tape(tex, w, h, 0x2F3F30, -700, 100, 3);
    tape(tex, w, h, 0x2F3F30, -800, 42, 3);
    tape(tex, w, h, 0x8FEF30, 300, 100, -3);
    tape(tex, w, h, 0x2534FF, 500, 100, -3);
    tape(tex, w, h, 0x700023, 900, 100, -4);
    tape(tex, w, h, 0x561134, 950, 50, -5);
    tape(tex, w, h, 0x002300, 975, 25, -6);
    tape(tex, w, h, 0x424242, 1300, 50, 1);

    gradient(tex, w, h, 0x3732FF, 0x0);
}

int main()
{
    Imlib_Image img;
    Imlib_Image scaled_img;
    Color *tex;

    srand(time(NULL));

    img = imlib_create_image(4*851, 4*315);
    imlib_context_set_image(img);

    draw(imlib_image_get_data(), 4*851, 4*315);

    scaled_img = imlib_create_cropped_scaled_image(
        0, 0, 4*851, 4*315, 2*851, 2*315
    );
    imlib_free_image();
    imlib_context_set_image(scaled_img);
    imlib_save_image("out.png");
    imlib_free_image();
    return 0;
}